Refactoring feed download + favicon cache

CHANGELOG.md

@@ -12,6 +12,7 @@ and this project does adhere to [Semantic Versioning](https://semver.org/spec/v2
 - Associate OPML files (double click and right click actions in Finder)
 - Quick Look preview for OPML files
 - *Adding feed:* 5xx server errors have a reload button which will initiate a new download with the same URL
+- *Adding feed:* Empty feed title will automatically reuse title from xml file (even if xml title changes)
 - *Adding feed:* `⌘R` will reload the same URL
 - *Settings, Feeds:* `⌘R` will reload the data source
 - *Settings, Feeds:* Refresh interval string localizations
@@ -26,11 +27,12 @@ and this project does adhere to [Semantic Versioning](https://semver.org/spec/v2
 - Config URL scheme `barss:` with `open/preferences` and `config/fixcache`
 
 ### Fixed
-- *Adding feed:* Show users any 5xx server error response and extracted failure reason
+- *Adding feed:* Show proper HTTP status code error message (4xx and 5xx)
+- *Adding feed:* Show (HTML) extracted failure reason for 5xx server errors
 - *Adding feed:* If URLs can't be resolved in the first run (5xx error), try a second time. E.g., `Done` click (issue: #5)
 - *Adding feed:* Prefer favicons with size `32x32`
-- *Adding feed:* Inserting feeds when offline will postpone download until network is reachable again
+- *Adding feed:* Inserting feeds when offline/paused will postpone download until network is reachable again
-- *Adding feed:* Inserting feeds when paused will postpone download until unpaused 
+- *Adding feed:* `Cancel` will indeed cancel download, not just continue and ignore results
 - *Settings, Feeds:* Actions `delete` and `edit` use clicked items instead of selected items
 - *Settings, Feeds:* Status info with accurate download count (instead of `Updating feeds …`)
 - *Settings, Feeds:* Status info shows `No network connection` and `Updates paused`
@@ -53,6 +55,7 @@ and this project does adhere to [Semantic Versioning](https://semver.org/spec/v2
 - *UI:* Interface builder files replaced with code equivalent
 - *UI:* Mark unread articles with blue dot, instead of tick mark
 - *DB*: New table for options. E.g., what app version modified the database
+- Dropping database table `FeedIcon` in favor of image files cache
 
 
 ## [0.9.4] - 2019-04-02

baRSS.xcodeproj/project.pbxproj

@@ -17,6 +17,7 @@
 		544DCCB9212A2B4D002DBC46 /* RSXML.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 544DCCB8212A2B4D002DBC46 /* RSXML.framework */; };
 		544DCCBA212A2B4D002DBC46 /* RSXML.framework in Embed Frameworks */ = {isa = PBXBuildFile; fileRef = 544DCCB8212A2B4D002DBC46 /* RSXML.framework */; settings = {ATTRIBUTES = (CodeSignOnCopy, RemoveHeadersOnCopy, ); }; };
 		544DCCBE212A2B6F002DBC46 /* RSXML.framework.dSYM in CopyFiles */ = {isa = PBXBuildFile; fileRef = 544DCCBD212A2B6F002DBC46 /* RSXML.framework.dSYM */; };
+		54501010230E9C8600F0B165 /* FeedDownload.m in Sources */ = {isa = PBXBuildFile; fileRef = 5450100F230E9C8600F0B165 /* FeedDownload.m */; };
 		546A6A2922C583390034E806 /* SettingsGeneralView.m in Sources */ = {isa = PBXBuildFile; fileRef = 54D857D122802309001BA1C8 /* SettingsGeneralView.m */; };
 		546A6A2C22C584AF0034E806 /* SettingsAppearanceView.m in Sources */ = {isa = PBXBuildFile; fileRef = 546A6A2A22C584AF0034E806 /* SettingsAppearanceView.m */; };
 		546A6A2F22C585580034E806 /* SettingsAboutView.m in Sources */ = {isa = PBXBuildFile; fileRef = 546A6A2D22C585580034E806 /* SettingsAboutView.m */; };
@@ -24,6 +25,7 @@
 		546FC44321189975007CC3A3 /* SettingsGeneral.m in Sources */ = {isa = PBXBuildFile; fileRef = 546FC44121189975007CC3A3 /* SettingsGeneral.m */; };
 		5477D34E21233C62002BA27F /* FeedGroup+Ext.m in Sources */ = {isa = PBXBuildFile; fileRef = 5477D34D21233C62002BA27F /* FeedGroup+Ext.m */; };
 		5478DF04225A7AE200D30C64 /* SettingsFeedsView.m in Sources */ = {isa = PBXBuildFile; fileRef = 5478DF03225A7AE200D30C64 /* SettingsFeedsView.m */; };
+		548C6D0A230C33DE003A1AAF /* NSURL+Ext.m in Sources */ = {isa = PBXBuildFile; fileRef = 548C6D09230C33DE003A1AAF /* NSURL+Ext.m */; };
 		5496B511214D6275003ED4ED /* UserPrefs.m in Sources */ = {isa = PBXBuildFile; fileRef = 5496B510214D6275003ED4ED /* UserPrefs.m */; };
 		54A07A7F220E04CF00082C51 /* NSFetchRequest+Ext.m in Sources */ = {isa = PBXBuildFile; fileRef = 54A07A7E220E04CF00082C51 /* NSFetchRequest+Ext.m */; };
 		54A07A82220E723D00082C51 /* MapUnreadTotal.m in Sources */ = {isa = PBXBuildFile; fileRef = 54A07A81220E723D00082C51 /* MapUnreadTotal.m */; };
@@ -31,11 +33,12 @@
 		54ACC28C21061B3C0020715F /* main.m in Sources */ = {isa = PBXBuildFile; fileRef = 54ACC28B21061B3C0020715F /* main.m */; };
 		54ACC29521061E270020715F /* UpdateScheduler.m in Sources */ = {isa = PBXBuildFile; fileRef = 54ACC29421061E270020715F /* UpdateScheduler.m */; };
 		54ACC29821061FBA0020715F /* Preferences.m in Sources */ = {isa = PBXBuildFile; fileRef = 54ACC29721061FBA0020715F /* Preferences.m */; };
-		54AD4E0023005297000AE386 /* WebFeed.m in Sources */ = {isa = PBXBuildFile; fileRef = 54AD4DFF23005297000AE386 /* WebFeed.m */; };
 		54AD4E0C2301853D000AE386 /* NSString+Ext.m in Sources */ = {isa = PBXBuildFile; fileRef = 54AD4E0B2301853D000AE386 /* NSString+Ext.m */; };
 		54AD4EE72305B17D000AE386 /* container-migration.plist in Resources */ = {isa = PBXBuildFile; fileRef = 54AD4EE62305B17D000AE386 /* container-migration.plist */; };
 		54B51704226DC339006C1B29 /* ModalFeedEditView.m in Sources */ = {isa = PBXBuildFile; fileRef = 54B51703226DC339006C1B29 /* ModalFeedEditView.m */; };
 		54B517072270E990006C1B29 /* NSView+Ext.m in Sources */ = {isa = PBXBuildFile; fileRef = 54B517062270E92A006C1B29 /* NSView+Ext.m */; };
+		54B6F14A231551B3002C94C9 /* FaviconDownload.m in Sources */ = {isa = PBXBuildFile; fileRef = 54B6F149231551B3002C94C9 /* FaviconDownload.m */; };
+		54B6F14E23155E1A002C94C9 /* NSURLRequest+Ext.m in Sources */ = {isa = PBXBuildFile; fileRef = 54B6F14D23155E1A002C94C9 /* NSURLRequest+Ext.m */; };
 		54B749DA2204A85C0022CC6D /* BarStatusItem.m in Sources */ = {isa = PBXBuildFile; fileRef = 54B749D92204A85C0022CC6D /* BarStatusItem.m */; };
 		54B749E0220636200022CC6D /* FeedArticle+Ext.m in Sources */ = {isa = PBXBuildFile; fileRef = 54B749DF220635CD0022CC6D /* FeedArticle+Ext.m */; };
 		54BB048921FD2AB500C303A5 /* NSDate+Ext.m in Sources */ = {isa = PBXBuildFile; fileRef = 54BB048821FD2AB500C303A5 /* NSDate+Ext.m */; };
@@ -43,6 +46,7 @@
 		54D55D7322E624CD00057B98 /* SettingsFeeds+DragDrop.m in Sources */ = {isa = PBXBuildFile; fileRef = 54D55D7222E624CD00057B98 /* SettingsFeeds+DragDrop.m */; };
 		54D857CE227C5785001BA1C8 /* RefreshStatisticsView.m in Sources */ = {isa = PBXBuildFile; fileRef = 54D857CD227C5785001BA1C8 /* RefreshStatisticsView.m */; };
 		54E3C02122EE076D006E2E24 /* opml-icon.icns in Resources */ = {isa = PBXBuildFile; fileRef = 54E3C02022EE076D006E2E24 /* opml-icon.icns */; };
+		54E4446C2329AE0600BBF481 /* NSError+Ext.m in Sources */ = {isa = PBXBuildFile; fileRef = 54E4446B2329AE0600BBF481 /* NSError+Ext.m */; };
 		54E88320211B509D00064188 /* ModalFeedEdit.m in Sources */ = {isa = PBXBuildFile; fileRef = 54E8831E211B509D00064188 /* ModalFeedEdit.m */; };
 		54E9CF32225914300023696F /* SettingsAbout.m in Sources */ = {isa = PBXBuildFile; fileRef = 54E9CF31225914300023696F /* SettingsAbout.m */; };
 		54F39C2E210BE1F700AEE730 /* DBv1.xcdatamodeld in Sources */ = {isa = PBXBuildFile; fileRef = 54ACC28221061B3B0020715F /* DBv1.xcdatamodeld */; };
@@ -114,6 +118,8 @@
 		544B011C2114EE9100386E5C /* AppHook.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = AppHook.m; sourceTree = "<group>"; };
 		544DCCB8212A2B4D002DBC46 /* RSXML.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = RSXML.framework; path = Carthage/Build/Mac/RSXML.framework; sourceTree = "<group>"; };
 		544DCCBD212A2B6F002DBC46 /* RSXML.framework.dSYM */ = {isa = PBXFileReference; lastKnownFileType = wrapper.dsym; name = RSXML.framework.dSYM; path = Carthage/Build/Mac/RSXML.framework.dSYM; sourceTree = "<group>"; };
+		5450100E230E9C8600F0B165 /* FeedDownload.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = FeedDownload.h; sourceTree = "<group>"; };
+		5450100F230E9C8600F0B165 /* FeedDownload.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = FeedDownload.m; sourceTree = "<group>"; };
 		546A6A2A22C584AF0034E806 /* SettingsAppearanceView.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = SettingsAppearanceView.m; sourceTree = "<group>"; };
 		546A6A2B22C584AF0034E806 /* SettingsAppearanceView.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = SettingsAppearanceView.h; sourceTree = "<group>"; };
 		546A6A2D22C585580034E806 /* SettingsAboutView.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = SettingsAboutView.m; sourceTree = "<group>"; };
@@ -127,6 +133,8 @@
 		5478DF02225A7AE200D30C64 /* SettingsFeedsView.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = SettingsFeedsView.h; sourceTree = "<group>"; };
 		5478DF03225A7AE200D30C64 /* SettingsFeedsView.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = SettingsFeedsView.m; sourceTree = "<group>"; };
 		54892F1D2235285700271CBA /* CHANGELOG.md */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = net.daringfireball.markdown; path = CHANGELOG.md; sourceTree = "<group>"; };
+		548C6D08230C33DE003A1AAF /* NSURL+Ext.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = "NSURL+Ext.h"; sourceTree = "<group>"; };
+		548C6D09230C33DE003A1AAF /* NSURL+Ext.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = "NSURL+Ext.m"; sourceTree = "<group>"; };
 		5496B50F214D6275003ED4ED /* UserPrefs.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = UserPrefs.h; sourceTree = "<group>"; };
 		5496B510214D6275003ED4ED /* UserPrefs.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = UserPrefs.m; sourceTree = "<group>"; };
 		54A07A7D220E04CF00082C51 /* NSFetchRequest+Ext.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = "NSFetchRequest+Ext.h"; sourceTree = "<group>"; };
@@ -142,8 +150,6 @@
 		54ACC29421061E270020715F /* UpdateScheduler.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = UpdateScheduler.m; sourceTree = "<group>"; };
 		54ACC29621061FBA0020715F /* Preferences.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = Preferences.h; sourceTree = "<group>"; };
 		54ACC29721061FBA0020715F /* Preferences.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = Preferences.m; sourceTree = "<group>"; };
-		54AD4DFE23005297000AE386 /* WebFeed.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = WebFeed.h; sourceTree = "<group>"; };
-		54AD4DFF23005297000AE386 /* WebFeed.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = WebFeed.m; sourceTree = "<group>"; };
 		54AD4E0A2301853D000AE386 /* NSString+Ext.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = "NSString+Ext.h"; sourceTree = "<group>"; };
 		54AD4E0B2301853D000AE386 /* NSString+Ext.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = "NSString+Ext.m"; sourceTree = "<group>"; };
 		54AD4EE42305AF60000AE386 /* baRSS.entitlements */ = {isa = PBXFileReference; lastKnownFileType = text.plist.entitlements; path = baRSS.entitlements; sourceTree = "<group>"; };
@@ -152,6 +158,10 @@
 		54B51703226DC339006C1B29 /* ModalFeedEditView.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = ModalFeedEditView.m; sourceTree = "<group>"; };
 		54B517052270E8C6006C1B29 /* NSView+Ext.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = "NSView+Ext.h"; sourceTree = "<group>"; };
 		54B517062270E92A006C1B29 /* NSView+Ext.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = "NSView+Ext.m"; sourceTree = "<group>"; };
+		54B6F148231551B3002C94C9 /* FaviconDownload.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = FaviconDownload.h; sourceTree = "<group>"; };
+		54B6F149231551B3002C94C9 /* FaviconDownload.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = FaviconDownload.m; sourceTree = "<group>"; };
+		54B6F14C23155E1A002C94C9 /* NSURLRequest+Ext.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = "NSURLRequest+Ext.h"; sourceTree = "<group>"; };
+		54B6F14D23155E1A002C94C9 /* NSURLRequest+Ext.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = "NSURLRequest+Ext.m"; sourceTree = "<group>"; };
 		54B749D82204A85C0022CC6D /* BarStatusItem.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = BarStatusItem.h; sourceTree = "<group>"; };
 		54B749D92204A85C0022CC6D /* BarStatusItem.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = BarStatusItem.m; sourceTree = "<group>"; };
 		54B749DE220635BE0022CC6D /* FeedArticle+Ext.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = "FeedArticle+Ext.h"; sourceTree = "<group>"; };
@@ -166,6 +176,8 @@
 		54D857D022802309001BA1C8 /* SettingsGeneralView.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = SettingsGeneralView.h; sourceTree = "<group>"; };
 		54D857D122802309001BA1C8 /* SettingsGeneralView.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = SettingsGeneralView.m; sourceTree = "<group>"; };
 		54E3C02022EE076D006E2E24 /* opml-icon.icns */ = {isa = PBXFileReference; lastKnownFileType = image.icns; path = "opml-icon.icns"; sourceTree = "<group>"; };
+		54E4446A2329AE0600BBF481 /* NSError+Ext.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = "NSError+Ext.h"; sourceTree = "<group>"; };
+		54E4446B2329AE0600BBF481 /* NSError+Ext.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = "NSError+Ext.m"; sourceTree = "<group>"; };
 		54E8831D211B509D00064188 /* ModalFeedEdit.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ModalFeedEdit.h; sourceTree = "<group>"; };
 		54E8831E211B509D00064188 /* ModalFeedEdit.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = ModalFeedEdit.m; sourceTree = "<group>"; };
 		54E9CF30225914300023696F /* SettingsAbout.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = SettingsAbout.h; sourceTree = "<group>"; };
@@ -210,12 +222,18 @@
 			children = (
 				54209E922117325100F3B5EF /* DrawImage.h */,
 				54209E932117325100F3B5EF /* DrawImage.m */,
-				54BB048721FD2AB500C303A5 /* NSDate+Ext.h */,
-				54BB048821FD2AB500C303A5 /* NSDate+Ext.m */,
 				54B517052270E8C6006C1B29 /* NSView+Ext.h */,
 				54B517062270E92A006C1B29 /* NSView+Ext.m */,
 				54AD4E0A2301853D000AE386 /* NSString+Ext.h */,
 				54AD4E0B2301853D000AE386 /* NSString+Ext.m */,
+				54BB048721FD2AB500C303A5 /* NSDate+Ext.h */,
+				54BB048821FD2AB500C303A5 /* NSDate+Ext.m */,
+				54E4446A2329AE0600BBF481 /* NSError+Ext.h */,
+				54E4446B2329AE0600BBF481 /* NSError+Ext.m */,
+				548C6D08230C33DE003A1AAF /* NSURL+Ext.h */,
+				548C6D09230C33DE003A1AAF /* NSURL+Ext.m */,
+				54B6F14C23155E1A002C94C9 /* NSURLRequest+Ext.h */,
+				54B6F14D23155E1A002C94C9 /* NSURLRequest+Ext.m */,
 			);
 			path = Helper;
 			sourceTree = "<group>";
@@ -316,8 +334,10 @@
 			children = (
 				54ACC29321061E270020715F /* UpdateScheduler.h */,
 				54ACC29421061E270020715F /* UpdateScheduler.m */,
-				54AD4DFE23005297000AE386 /* WebFeed.h */,
+				5450100E230E9C8600F0B165 /* FeedDownload.h */,
-				54AD4DFF23005297000AE386 /* WebFeed.m */,
+				5450100F230E9C8600F0B165 /* FeedDownload.m */,
+				54B6F148231551B3002C94C9 /* FaviconDownload.h */,
+				54B6F149231551B3002C94C9 /* FaviconDownload.m */,
 				54F6025B21C1D4170006D338 /* OpmlFile.h */,
 				54F6025C21C1D4170006D338 /* OpmlFile.m */,
 			);
@@ -537,7 +557,6 @@
 			isa = PBXSourcesBuildPhase;
 			buildActionMask = 2147483647;
 			files = (
-				54AD4E0023005297000AE386 /* WebFeed.m in Sources */,
 				54B51704226DC339006C1B29 /* ModalFeedEditView.m in Sources */,
 				54AD4E0C2301853D000AE386 /* NSString+Ext.m in Sources */,
 				546A6A2C22C584AF0034E806 /* SettingsAppearanceView.m in Sources */,
@@ -551,9 +570,12 @@
 				54ACC29521061E270020715F /* UpdateScheduler.m in Sources */,
 				54BB048921FD2AB500C303A5 /* NSDate+Ext.m in Sources */,
 				5477D34E21233C62002BA27F /* FeedGroup+Ext.m in Sources */,
+				54B6F14A231551B3002C94C9 /* FaviconDownload.m in Sources */,
+				54E4446C2329AE0600BBF481 /* NSError+Ext.m in Sources */,
 				5478DF04225A7AE200D30C64 /* SettingsFeedsView.m in Sources */,
 				540F704521B6C16C0022E69D /* FeedMeta+Ext.m in Sources */,
 				54ACC28C21061B3C0020715F /* main.m in Sources */,
+				54B6F14E23155E1A002C94C9 /* NSURLRequest+Ext.m in Sources */,
 				54FE73D3212316CD003EAC65 /* BarMenu.m in Sources */,
 				544B011A2114B41200386E5C /* ModalSheet.m in Sources */,
 				54A07A82220E723D00082C51 /* MapUnreadTotal.m in Sources */,
@@ -567,8 +589,10 @@
 				541C67C32255470B004D2CE6 /* SettingsAppearance.m in Sources */,
 				54B749DA2204A85C0022CC6D /* BarStatusItem.m in Sources */,
 				546FC43D21188AD5007CC3A3 /* SettingsFeeds.m in Sources */,
+				548C6D0A230C33DE003A1AAF /* NSURL+Ext.m in Sources */,
 				54E88320211B509D00064188 /* ModalFeedEdit.m in Sources */,
 				54195883218A061100581B79 /* Feed+Ext.m in Sources */,
+				54501010230E9C8600F0B165 /* FeedDownload.m in Sources */,
 				54209E942117325100F3B5EF /* DrawImage.m in Sources */,
 				54FE73D021220DEC003EAC65 /* StoreCoordinator.m in Sources */,
 				54A07A7F220E04CF00082C51 /* NSFetchRequest+Ext.m in Sources */,

baRSS/AppHook.m

@@ -22,14 +22,14 @@
 
 #import "AppHook.h"
 #import "Constants.h"
-#import "BarStatusItem.h"
-#import "WebFeed.h"
-#import "UpdateScheduler.h"
-#import "Preferences.h"
 #import "DrawImage.h"
-#import "SettingsFeeds+DragDrop.h"
 #import "UserPrefs.h"
+#import "Preferences.h"
+#import "BarStatusItem.h"
+#import "UpdateScheduler.h"
 #import "StoreCoordinator.h"
+#import "SettingsFeeds+DragDrop.h"
+#import "NSURL+Ext.h"
 
 @interface AppHook()
 @property (strong) NSWindowController *prefWindow;
@@ -53,11 +53,15 @@
 }
 
 - (void)applicationDidFinishLaunching:(NSNotification *)aNotification {
+	BOOL initial = [[NSURL faviconsCacheURL] mkdir];
 	[_statusItem asyncReloadUnreadCount];
 	[UpdateScheduler registerNetworkChangeNotification]; // will call update scheduler
 	if ([StoreCoordinator isEmpty]) {
 		[_statusItem showWelcomeMessage];
-		[WebFeed autoDownloadAndParseUpdateURL];
+		[UpdateScheduler autoDownloadAndParseUpdateURL];
+	} else {
+		// mostly for version migration 0.9.4 ~> 1.0 (favicon storage)
+		if (initial) [UpdateScheduler updateAllFavicons];
 	}
 }
 
@@ -109,8 +113,8 @@
 
 @synthesize persistentContainer = _persistentContainer;
 
+/// The persistent container for the application. This implementation creates and returns a container, having loaded the store for the application to it.
 - (NSPersistentContainer *)persistentContainer {
-	// The persistent container for the application. This implementation creates and returns a container, having loaded the store for the application to it.
 	@synchronized (self) {
 		if (_persistentContainer == nil) {
 			_persistentContainer = [[NSPersistentContainer alloc] initWithName:@"DBv1"];
@@ -125,28 +129,23 @@
 	return _persistentContainer;
 }
 
+/// Save changes in the application's managed object context before the application terminates.
 - (NSApplicationTerminateReply)applicationShouldTerminate:(NSApplication *)sender {
-	// Save changes in the application's managed object context before the application terminates.
 	NSManagedObjectContext *context = self.persistentContainer.viewContext;
-	
 	if (![context commitEditing]) {
 		NSLog(@"%@:%@ unable to commit editing to terminate", [self class], NSStringFromSelector(_cmd));
 		return NSTerminateCancel;
 	}
-	
 	if (!context.hasChanges) {
 		return NSTerminateNow;
 	}
-	
 	NSError *error = nil;
 	if (![context save:&error]) {
-		
 		// Customize this code block to include application-specific recovery steps.
 		BOOL result = [sender presentError:error];
 		if (result) {
 			return NSTerminateCancel;
 		}
-		
 		NSString *question = NSLocalizedString(@"Could not save changes while quitting. Quit anyway?", @"Quit without saves error question message");
 		NSString *info = NSLocalizedString(@"Quitting now will lose any changes you have made since the last successful save", @"Quit without saves error question info");
 		NSString *quitButton = NSLocalizedString(@"Quit anyway", @"Quit anyway button title");
@@ -157,9 +156,7 @@
 		[alert addButtonWithTitle:quitButton];
 		[alert addButtonWithTitle:cancelButton];
 		
-		NSInteger answer = [alert runModal];
+		if ([alert runModal] == NSAlertSecondButtonReturn) {
-		
-		if (answer == NSAlertSecondButtonReturn) {
 			return NSTerminateCancel;
 		}
 	}
@@ -170,9 +167,7 @@
 #pragma mark - Application Input (URLs and Files)
 
 
-/**
+/// Callback method fired on opml file import
- Callback method fired on opml file import
- */
 - (void)application:(NSApplication *)sender openFiles:(NSArray<NSString *> *)filenames {
 	NSMutableArray<NSURL*> *urls = [NSMutableArray arrayWithCapacity:filenames.count];
 	for (NSString *file in filenames) {
@@ -184,9 +179,7 @@
 	[sender replyToOpenOrPrint:NSApplicationDelegateReplySuccess];
 }
 
-/**
+/// Callback method fired when opened with an URL (@c feed: and @c barss: scheme)
- Callback method fired when opened with an URL (@c feed: and @c barss: scheme)
- */
 - (void)handleAppleEvent:(NSAppleEventDescriptor *)event withReplyEvent:(NSAppleEventDescriptor *)replyEvent {
 	NSString *url = [[event paramDescriptorForKeyword:keyDirectObject] stringValue];
 	NSString *scheme = [[[NSURL URLWithString:url] scheme] lowercaseString];
@@ -195,7 +188,7 @@
 		url = [url substringFromIndex:2];
 	}
 	if ([scheme isEqualToString:kURLSchemeFeed]) {
-		[WebFeed autoDownloadAndParseURL:url addAnyway:NO modify:nil];
+		[UpdateScheduler autoDownloadAndParseURL:url];
 	} else if ([scheme isEqualToString:kURLSchemeBarss]) {
 		NSMutableArray<NSString*> *comp = [[url pathComponents] mutableCopy];
 		NSString *action = comp.firstObject;

baRSS/Constants.h

@@ -61,8 +61,8 @@ static NSImageName const RSSImageMenuItemUnread    = @"RSSImageMenuItemUnread";
 
 
 /// Helper method calls @c (defaultCenter)postNotification:
-NS_INLINE void PostNotification(NSNotificationName name, id obj) { [[NSNotificationCenter defaultCenter] postNotificationName:name object:obj]; }
+static inline void PostNotification(NSNotificationName name, id obj) { [[NSNotificationCenter defaultCenter] postNotificationName:name object:obj]; }
-NS_INLINE void RegisterNotification(NSNotificationName name, SEL action, id observer) { [[NSNotificationCenter defaultCenter] addObserver:observer selector:action name:name object:nil]; }
+static inline void RegisterNotification(NSNotificationName name, SEL action, id observer) { [[NSNotificationCenter defaultCenter] addObserver:observer selector:action name:name object:nil]; }
 /**
  @c notification.object is @c NSNumber of type @c NSUInteger.
  Represents number of feeds that are proccessed in background update. Sends @c 0 when all downloads are finished.
@@ -77,12 +77,12 @@ static NSNotificationName const kNotificationScheduleTimerChanged = @"baRSS-noti
  @c notification.object is @c NSManagedObjectID of type @c FeedGroup.
  Called whenever a new feed group was created in @c autoDownloadAndParseURL:
  */
-static NSNotificationName const kNotificationGroupInserted = @"baRSS-notification-group-inserted";
+static NSNotificationName const kNotificationFeedGroupInserted = @"baRSS-notification-feed-inserted";
 /**
  @c notification.object is @c NSManagedObjectID of type @c Feed.
- Called whenever download of a feed finished and object was modified (not if statusCode 304).
+ Called whenever download of a feed finished and articles were modified (not if statusCode 304).
  */
-static NSNotificationName const kNotificationFeedUpdated = @"baRSS-notification-feed-updated";
+static NSNotificationName const kNotificationArticlesUpdated = @"baRSS-notification-articles-updated";
 /**
  @c notification.object is @c NSManagedObjectID of type @c Feed.
  Called whenever the icon attribute of an item was updated.

baRSS/Core Data/Feed+Ext.h

@@ -25,16 +25,16 @@
 @class RSParsedFeed;
 
 @interface Feed (Ext)
+@property (readonly) BOOL hasIcon;
 @property (nonnull, readonly) NSImage* iconImage16;
 
 // Generator methods / Feed update
 + (instancetype)newFeedAndMetaInContext:(NSManagedObjectContext*)context;
-+ (instancetype)appendToRootWithDefaultIntervalInContext:(NSManagedObjectContext*)moc;
 - (void)updateWithRSS:(RSParsedFeed*)obj postUnreadCountChange:(BOOL)flag;
-- (void)calculateAndSetIndexPathString;
 - (NSMenuItem*)newMenuItem;
+// Getter & Setter
+- (void)calculateAndSetIndexPathString;
+- (void)setNewIcon:(NSURL*)location;
 // Article properties
 - (NSArray<FeedArticle*>*)sortedArticles;
-// Icon
-- (BOOL)setIconImage:(NSImage*)img;
 @end

baRSS/Core Data/Feed+Ext.m

@@ -28,6 +28,7 @@
 #import "FeedGroup+Ext.h"
 #import "FeedArticle+Ext.h"
 #import "StoreCoordinator.h"
+#import "NSURL+Ext.h"
 
 @implementation Feed (Ext)
 
@@ -38,14 +39,6 @@
 	return feed;
 }
 
-/// Instantiates new @c FeedGroup with @c FEED type, set the update interval to @c 30min and @c sortIndex to last root index.
-+ (instancetype)appendToRootWithDefaultIntervalInContext:(NSManagedObjectContext*)moc {
-	NSUInteger lastIndex = [StoreCoordinator countRootItemsInContext:moc];
-	FeedGroup *fg = [FeedGroup newGroup:FEED inContext:moc];
-	[fg setParent:nil andSortIndex:(int32_t)lastIndex];
-	return fg.feed;
-}
-
 /// Call @c indexPathString on @c .group and update @c .indexPath if current value is different.
 - (void)calculateAndSetIndexPathString {
 	NSString *pthStr = [self.group indexPathString];
@@ -56,7 +49,7 @@
 /// @return Fully initialized @c NSMenuItem with @c title, @c tooltip, @c image, and @c action.
 - (NSMenuItem*)newMenuItem {
 	NSMenuItem *item = [NSMenuItem new];
-	item.title = self.group.nameOrError;
+	item.title = self.group.anyName;
 	item.toolTip = self.subtitle;
 	item.enabled = (self.articles.count > 0);
 	item.image = self.iconImage16;
@@ -85,9 +78,6 @@
 	if (![self.subtitle isEqualToString:obj.subtitle]) self.subtitle = obj.subtitle;
 	if (![self.link isEqualToString:obj.link])         self.link = obj.link;
 	
-	if (self.group.name.length == 0) // in case a blank group was initialized
-		self.group.name = obj.title;
-	
 	// Add and remove articles
 	NSMutableSet<FeedArticle*> *localSet = [self.articles mutableCopy];
 	NSInteger diff = 0;
@@ -117,6 +107,7 @@
 		// reverse enumeration ensures correct article order
 		FeedArticle *storedArticle = [self findRemoteArticle:article inLocalSet:localSet];
 		if (storedArticle) {
+			// TODO: stop bullshitting with ghost articles
 			[localSet removeObject:storedArticle];
 			// If we encounter an already existing item, assume newly inserted are "ghost" items and mark read.
 			if (newlyInserted.count > 0) {
@@ -215,15 +206,13 @@
 #pragma mark - Icon -
 
 
-/**
+/// @return @c 16x16px image. Either from favicon cache or generated default RSS icon.
- @return Return @c 16x16px image. Either from core data storage or generated default RSS icon.
- */
 - (nonnull NSImage*)iconImage16 {
 	NSImage *img = nil;
 	if (self.articles.count == 0) {
 		img = [NSImage imageNamed:NSImageNameCaution];
-	} else if (self.icon.icon) {
+	} else if (self.hasIcon) {
-		img = [[NSImage alloc] initWithData:self.icon.icon];
+		img = [[NSImage alloc] initByReferencingURL:[self iconPath]];
 	} else {
 		img = [NSImage imageNamed:RSSImageDefaultRSSIcon];
 	}
@@ -231,23 +220,26 @@
 	return img;
 }
 
-/**
+/// Checks if file at @c iconPath is an actual file
- Set favicon icon or delete relationship if @c img is not a valid image.
+- (BOOL)hasIcon { return [[self iconPath] existsAndIsDir:NO]; }
 
- @return @c YES if icon was updated (core data did change).
+/// Image file path at e.g., "Application Support/baRSS/favicons/p42". @warning File may not exist!
-*/
+- (NSURL*)iconPath {
-- (BOOL)setIconImage:(NSImage*)img {
+	NSString *pk = self.objectID.URIRepresentation.lastPathComponent;
-	if (img && [img isValid]) {
+	return [[NSURL faviconsCacheURL] URLByAppendingPathComponent:pk isDirectory:NO];
-		if (!self.icon)
+}
-			self.icon = [[FeedIcon alloc] initWithEntity:FeedIcon.entity insertIntoManagedObjectContext:self.managedObjectContext];
+
-		self.icon.icon = [img TIFFRepresentation];
+/// Move favicon from @c $TMPDIR to permanent destination in Application Support.
-		return YES;
+- (void)setNewIcon:(NSURL*)location {
-	} else if (self.icon) {
+	if (!location) {
-		[self.managedObjectContext deleteObject:self.icon];
+		[[self iconPath] remove];
-		self.icon = nil;
+	} else {
-		return YES;
+		if (self.objectID.isTemporaryID) {
+			[self.managedObjectContext obtainPermanentIDsForObjects:@[self] error:nil];
+		}
+		[location moveTo:[self iconPath]];
+		PostNotification(kNotificationFeedIconUpdated, self.objectID);
 	}
-	return NO;
 }
 
 @end

baRSS/Core Data/FeedGroup+Ext.h

@@ -33,14 +33,15 @@ typedef NS_ENUM(int16_t, FeedGroupType) {
 @interface FeedGroup (Ext)
 /// Overwrites @c type attribute with enum. Use one of: @c GROUP, @c FEED, @c SEPARATOR.
 @property (nonatomic) FeedGroupType type;
-@property (nonnull, readonly) NSString *nameOrError;
+@property (nonnull, readonly) NSString *anyName;
 @property (nonnull, readonly) NSImage* groupIconImage16;
 @property (nonnull, readonly) NSImage* iconImage16;
 
 + (instancetype)newGroup:(FeedGroupType)type inContext:(NSManagedObjectContext*)context;
++ (instancetype)appendToRoot:(FeedGroupType)type inContext:(NSManagedObjectContext*)moc;
 - (void)setParent:(FeedGroup *)parent andSortIndex:(int32_t)sortIndex;
 - (void)setSortIndexIfChanged:(int32_t)sortIndex;
-- (void)setNameIfChanged:(NSString*)name;
+- (void)setNameIfChanged:(nullable NSString*)name;
 - (NSMenuItem*)newMenuItem;
 // Handle children and parents
 - (NSString*)indexPathString;

baRSS/Core Data/FeedGroup+Ext.m

@@ -21,17 +21,22 @@
 //  SOFTWARE.
 
 #import "FeedGroup+Ext.h"
-#import "FeedMeta+Ext.h"
 #import "Feed+Ext.h"
+#import "FeedMeta+Ext.h"
+#import "StoreCoordinator.h"
 #import "NSDate+Ext.h"
 
 @implementation FeedGroup (Ext)
 
 #pragma mark - Properties
 
-/// @return Returns "(no title)" if @c self.name is @c nil.
+/// Try return @c self.name or @c self.feed.title ; If both fail return "(no title)"
-- (nonnull NSString*)nameOrError {
+- (nonnull NSString*)anyName {
-	return (self.name ? self.name : NSLocalizedString(@"(no title)", nil));
+	if (self.name.length > 0)
+		return self.name;
+	if (self.type == FEED && self.feed.title.length > 0)
+		return self.feed.title;
+	return NSLocalizedString(@"(no title)", nil);
 }
 
 /// @return Return @c 16x16px NSImageNameFolder image.
@@ -66,6 +71,14 @@
 	return fg;
 }
 
+/// Instantiates new @c FeedGroup at root level and append at end.
++ (instancetype)appendToRoot:(FeedGroupType)type inContext:(NSManagedObjectContext*)moc {
+	NSUInteger lastIndex = [StoreCoordinator countRootItemsInContext:moc];
+	FeedGroup *fg = [FeedGroup newGroup:type inContext:moc];
+	[fg setParent:nil andSortIndex:(int32_t)lastIndex];
+	return fg;
+}
+
 /// Set @c parent and @c sortIndex. Also if type is @c FEED calculate and set @c indexPath string.
 - (void)setParent:(FeedGroup *)parent andSortIndex:(int32_t)sortIndex {
 	self.parent = parent;
@@ -85,15 +98,19 @@
 }
 
 /// Set @c name attribute but only if value differs.
-- (void)setNameIfChanged:(NSString*)name {
+- (void)setNameIfChanged:(nullable NSString*)name {
-	if (![self.name isEqualToString: name])
+	if (name.length == 0) {
+		if (self.name.length > 0)
+			self.name = nil; // nullify empty strings
+	} else if (![self.name isEqualToString: name]) {
 		self.name = name;
 	}
+}
 
 /// @return Fully initialized @c NSMenuItem with @c title and @c image.
 - (NSMenuItem*)newMenuItem {
 	NSMenuItem *item = [NSMenuItem new];
-	item.title = self.nameOrError;
+	item.title = self.anyName;
 	item.enabled = (self.children.count > 0);
 	item.image = self.groupIconImage16;
 	item.representedObject = self.objectID;
@@ -155,8 +172,8 @@
 /// @return Simplified description of the feed object.
 - (NSString*)readableDescription {
 	switch (self.type) {
-		case GROUP:     return [NSString stringWithFormat:@"%@:", self.name];
+		case GROUP:     return [NSString stringWithFormat:@"%@:", self.anyName];
-		case FEED:      return [NSString stringWithFormat:@"%@ (%@)", self.name, self.feed.meta.url];
+		case FEED:      return [NSString stringWithFormat:@"%@ (%@)", self.anyName, self.feed.meta.url];
 		case SEPARATOR: return @"-------------";
 	}
 }

baRSS/Core Data/FeedMeta+Ext.h

@@ -32,6 +32,6 @@ static int32_t const kDefaultFeedRefreshInterval = 30 * 60;
 - (void)setSucessfulWithResponse:(NSHTTPURLResponse*)response;
 // Setter
 - (void)setUrlIfChanged:(NSString*)url;
-- (BOOL)setRefreshAndSchedule:(int32_t)refresh;
+- (void)setRefreshIfChanged:(int32_t)refresh;
 - (void)scheduleNow:(NSTimeInterval)future;
 @end

baRSS/Core Data/FeedMeta+Ext.m

@@ -51,6 +51,7 @@
 	[self scheduleNow:retryWaitTime];
 }
 
+/// Copy Etag & Last-Modified headers and update URL (if not 304). Then schedule new update date. Will reset errorCount to @c 0
 - (void)setSucessfulWithResponse:(NSHTTPURLResponse*)response {
 	self.errorCount = 0; // reset counter
 	NSDictionary *header = [response allHeaderFields];
@@ -68,26 +69,17 @@
 	if (![self.url isEqualToString:url]) self.url = url;
 }
 
+/// Set @c refresh attribute but only if value differs.
+- (void)setRefreshIfChanged:(int32_t)refresh {
+	if (self.refresh != refresh) self.refresh = refresh;
+}
+
 /// Set @c etag and @c modified attributes. Only values that differ will be updated.
 - (void)setEtag:(NSString*)etag modified:(NSString*)modified {
 	if (![self.etag isEqualToString:etag])         self.etag = etag;
 	if (![self.modified isEqualToString:modified]) self.modified = modified;
 }
 
-/**
- Set @c refresh and calculate new @c scheduled date.
-
- @return @c YES if refresh interval has changed
- */
-- (BOOL)setRefreshAndSchedule:(int32_t)refresh {
-	if (self.refresh != refresh) {
-		self.refresh = refresh;
-		[self scheduleNow:self.refresh];
-		return YES;
-	}
-	return NO;
-}
-
 /// Set next scheduled feed update or @c nil if @c refresh @c <= @c 0.
 - (void)scheduleNow:(NSTimeInterval)future {
 	if (self.refresh <= 0) { // update deactivated; manually update with force update all

baRSS/Core Data/StoreCoordinator.h

@@ -36,7 +36,7 @@ static int const dbFileVersion = 1; // update in case database structure changes
 
 // Feed update
 + (NSDate*)nextScheduledUpdate;
-+ (NSArray<Feed*>*)getListOfFeedsThatNeedUpdate:(BOOL)forceAll inContext:(NSManagedObjectContext*)moc;
++ (NSArray<Feed*>*)listOfFeedsThatNeedUpdate:(BOOL)forceAll inContext:(NSManagedObjectContext*)moc;
 
 // Count elements
 + (BOOL)isEmpty;
@@ -48,7 +48,6 @@ static int const dbFileVersion = 1; // update in case database structure changes
 + (NSArray<FeedGroup*>*)sortedFeedGroupsWithParent:(id)parent inContext:(NSManagedObjectContext*)moc;
 + (NSArray<FeedArticle*>*)sortedArticlesWithParent:(id)parent inContext:(NSManagedObjectContext*)moc;
 + (NSArray<Feed*>*)listOfFeedsMissingArticlesInContext:(NSManagedObjectContext*)moc;
-+ (NSArray<Feed*>*)listOfFeedsMissingIconsInContext:(NSManagedObjectContext*)moc;
 + (Feed*)feedWithIndexPath:(nonnull NSString*)path inContext:(NSManagedObjectContext*)moc;
 + (NSString*)urlForFeedWithIndexPath:(nonnull NSString*)path;
 
@@ -57,4 +56,5 @@ static int const dbFileVersion = 1; // update in case database structure changes
 
 // Restore sound state
 + (void)cleanupAndShowAlert:(BOOL)flag;
++ (NSUInteger)cleanupFavicons;
 @end

baRSS/Core Data/StoreCoordinator.m

@@ -21,10 +21,12 @@
 //  SOFTWARE.
 
 #import "StoreCoordinator.h"
-#import "Constants.h"
-#import "NSFetchRequest+Ext.h"
 #import "AppHook.h"
+#import "Constants.h"
+#import "FaviconDownload.h"
 #import "Feed+Ext.h"
+#import "NSURL+Ext.h"
+#import "NSFetchRequest+Ext.h"
 
 @implementation StoreCoordinator
 
@@ -57,7 +59,7 @@
 	NSError *error = nil;
 	if (context.hasChanges && ![context save:&error]) {
 		// Customize this code block to include application-specific recovery steps.
-		[[NSApplication sharedApplication] presentError:error];
+		[NSApp presentError:error];
 	}
 	if (flag && context.parentContext) {
 		[self saveContext:context.parentContext andParent:flag];
@@ -101,11 +103,11 @@
 
  @param forceAll If @c YES get a list of all @c Feed regardless of schedules time.
  */
-+ (NSArray<Feed*>*)getListOfFeedsThatNeedUpdate:(BOOL)forceAll inContext:(NSManagedObjectContext*)moc {
++ (NSArray<Feed*>*)listOfFeedsThatNeedUpdate:(BOOL)forceAll inContext:(NSManagedObjectContext*)moc {
 	NSFetchRequest *fr = [Feed fetchRequest];
 	if (!forceAll) {
-		// when fetching also get those feeds that would need update soon (now + 10s)
+		// when fetching also get those feeds that would need update soon (now + 2s)
-		[fr where:@"meta.scheduled <= %@", [NSDate dateWithTimeIntervalSinceNow:+10]];
+		[fr where:@"meta.scheduled <= %@", [NSDate dateWithTimeIntervalSinceNow:+2]];
 	}
 	return [fr fetchAllRows:moc];
 }
@@ -156,11 +158,6 @@
 	return [[[Feed fetchRequest] where:@"articles.@count == 0"] fetchAllRows:moc];
 }
 
-/// @return Unsorted list of @c Feed items where @c icon is @c nil.
-+ (NSArray<Feed*>*)listOfFeedsMissingIconsInContext:(NSManagedObjectContext*)moc {
-	return [[[Feed fetchRequest] where:@"icon = NULL"] fetchAllRows:moc];
-}
-
 /// @return Single @c Feed item where @c Feed.indexPath @c = @c path.
 + (Feed*)feedWithIndexPath:(nonnull NSString*)path inContext:(NSManagedObjectContext*)moc {
 	return [[[Feed fetchRequest] where:@"indexPath = %@", path] fetchFirst:moc];
@@ -225,6 +222,7 @@
 
 #pragma mark - Restore Sound State
 
+/// Remove orphan core data entries with optional alert message of removed items count.
 + (void)cleanupAndShowAlert:(BOOL)flag {
 	NSUInteger deleted = [self deleteUnreferenced];
 	[self restoreFeedIndexPaths];
@@ -256,7 +254,6 @@
 	NSManagedObjectContext *moc = [self getMainContext];
 	deleted += [self batchDelete:Feed.entity nullAttribute:@"group" inContext:moc];
 	deleted += [self batchDelete:FeedMeta.entity nullAttribute:@"feed" inContext:moc];
-	deleted += [self batchDelete:FeedIcon.entity nullAttribute:@"feed" inContext:moc];
 	deleted += [self batchDelete:FeedArticle.entity nullAttribute:@"feed" inContext:moc];
 	if (deleted > 0) {
 		[self saveContext:moc andParent:YES];
@@ -291,4 +288,25 @@
 	return [res.result unsignedIntegerValue];
 }
 
+/// Remove orphan favicons. @return Number of removed items.
++ (NSUInteger)cleanupFavicons {
+	NSURL *base = [[NSURL faviconsCacheURL] URLByResolvingSymlinksInPath];
+	if (![base existsAndIsDir:YES]) return 0;
+	
+	NSFileManager *fm = [NSFileManager defaultManager];
+	NSDirectoryEnumerationOptions opt = NSDirectoryEnumerationSkipsSubdirectoryDescendants | NSDirectoryEnumerationSkipsPackageDescendants | NSDirectoryEnumerationSkipsHiddenFiles;
+	NSDirectoryEnumerator *enumerator = [fm enumeratorAtURL:base includingPropertiesForKeys:nil options:opt errorHandler:nil];
+	NSMutableArray<NSURL*> *toBeDeleted = [NSMutableArray array];
+	
+	NSArray<NSManagedObjectID*> *feedIds = [[Feed fetchRequest] fetchIDs:[self getMainContext]];
+	NSArray<NSString*> *pks = [feedIds valueForKeyPath:@"URIRepresentation.lastPathComponent"];
+	
+	for (NSURL *path in enumerator)
+		if (![pks containsObject:path.lastPathComponent])
+			[toBeDeleted addObject:path];
+	for (NSURL *path in toBeDeleted)
+		[fm removeItemAtURL:path error:nil];
+	return toBeDeleted.count;
+}
+
 @end

baRSS/DBv1.xcdatamodeld/DBv1.xcdatamodel/contents

@@ -7,7 +7,6 @@
         <attribute name="title" optional="YES" attributeType="String" syncable="YES"/>
         <relationship name="articles" optional="YES" toMany="YES" deletionRule="Cascade" destinationEntity="FeedArticle" inverseName="feed" inverseEntity="FeedArticle" syncable="YES"/>
         <relationship name="group" optional="YES" maxCount="1" deletionRule="Nullify" destinationEntity="FeedGroup" inverseName="feed" inverseEntity="FeedGroup" syncable="YES"/>
-        <relationship name="icon" optional="YES" maxCount="1" deletionRule="Cascade" destinationEntity="FeedIcon" inverseName="feed" inverseEntity="FeedIcon" syncable="YES"/>
         <relationship name="meta" optional="YES" maxCount="1" deletionRule="Cascade" destinationEntity="FeedMeta" inverseName="feed" inverseEntity="FeedMeta" syncable="YES"/>
     </entity>
     <entity name="FeedArticle" representedClassName="FeedArticle" syncable="YES" codeGenerationType="class">
@@ -30,10 +29,6 @@
         <relationship name="feed" optional="YES" maxCount="1" deletionRule="Cascade" destinationEntity="Feed" inverseName="group" inverseEntity="Feed" syncable="YES"/>
         <relationship name="parent" optional="YES" maxCount="1" deletionRule="Nullify" destinationEntity="FeedGroup" inverseName="children" inverseEntity="FeedGroup" syncable="YES"/>
     </entity>
-    <entity name="FeedIcon" representedClassName="FeedIcon" syncable="YES" codeGenerationType="class">
-        <attribute name="icon" optional="YES" attributeType="Binary" allowsExternalBinaryDataStorage="YES" customClassName="NSImage" syncable="YES"/>
-        <relationship name="feed" optional="YES" maxCount="1" deletionRule="Nullify" destinationEntity="Feed" inverseName="icon" inverseEntity="Feed" syncable="YES"/>
-    </entity>
     <entity name="FeedMeta" representedClassName="FeedMeta" syncable="YES" codeGenerationType="class">
         <attribute name="errorCount" optional="YES" attributeType="Integer 16" defaultValueString="0" usesScalarValueType="YES" syncable="YES"/>
         <attribute name="etag" optional="YES" attributeType="String" syncable="YES"/>
@@ -48,10 +43,9 @@
         <attribute name="value" optional="YES" attributeType="String" syncable="YES"/>
     </entity>
     <elements>
-        <element name="Feed" positionX="-278.84765625" positionY="-112.953125" width="128" height="165"/>
+        <element name="Feed" positionX="-278.84765625" positionY="-112.953125" width="128" height="150"/>
         <element name="FeedArticle" positionX="-96.77734375" positionY="-113.83984375" width="128" height="195"/>
         <element name="FeedGroup" positionX="-460.37890625" positionY="-111.62890625" width="130.52734375" height="135"/>
-        <element name="FeedIcon" positionX="-202.79296875" positionY="137.71875" width="128" height="75"/>
         <element name="FeedMeta" positionX="-348.02734375" positionY="136.89453125" width="128" height="150"/>
         <element name="Options" positionX="-279" positionY="36" width="128" height="75"/>
     </elements>

baRSS/Feed Import/FaviconDownload.h

@@ -0,0 +1,47 @@
+//
+//  The MIT License (MIT)
+//  Copyright (c) 2019 Oleg Geier
+//
+//  Permission is hereby granted, free of charge, to any person obtaining a copy of
+//  this software and associated documentation files (the "Software"), to deal in
+//  the Software without restriction, including without limitation the rights to
+//  use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
+//  of the Software, and to permit persons to whom the Software is furnished to do
+//  so, subject to the following conditions:
+//
+//  The above copyright notice and this permission notice shall be included in all
+//  copies or substantial portions of the Software.
+//
+//  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+//  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+//  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+//  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+//  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+//  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+//  SOFTWARE.
+
+@import Cocoa;
+@class Feed, RSHTMLMetadata, FeedDownload;
+@protocol FaviconDownloadDelegate;
+
+@interface FaviconDownload : NSObject
+/// @c img and @c path are @c nil if image is not valid or couldn't be downloaded.
+typedef void(^FaviconDownloadBlock)(NSImage * _Nullable img, NSURL * _Nullable path);
+
+// Instantiation methods
++ (instancetype)withURL:(nonnull NSString*)urlStr isImageURL:(BOOL)flag;
++ (instancetype)updateFeed:(Feed*)feed finally:(nullable os_block_t)block;
+// Actions
+- (instancetype)startWithDelegate:(id<FaviconDownloadDelegate>)observer;
+- (instancetype)startWithBlock:(nonnull FaviconDownloadBlock)block;
+- (void)cancel;
+// Extract from HTML metadata
++ (nullable NSString*)urlForMetadata:(RSHTMLMetadata*)meta;
+@end
+
+
+@protocol FaviconDownloadDelegate <NSObject>
+@required
+/// Called after image download. Called on error, but not if download is cancled.
+- (void)faviconDownload:(FaviconDownload*)sender didFinish:(nullable NSURL*)path;
+@end

baRSS/Feed Import/FaviconDownload.m

@@ -0,0 +1,226 @@
+//
+//  The MIT License (MIT)
+//  Copyright (c) 2019 Oleg Geier
+//
+//  Permission is hereby granted, free of charge, to any person obtaining a copy of
+//  this software and associated documentation files (the "Software"), to deal in
+//  the Software without restriction, including without limitation the rights to
+//  use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
+//  of the Software, and to permit persons to whom the Software is furnished to do
+//  so, subject to the following conditions:
+//
+//  The above copyright notice and this permission notice shall be included in all
+//  copies or substantial portions of the Software.
+//
+//  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+//  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+//  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+//  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+//  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+//  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+//  SOFTWARE.
+
+@import RSXML;
+#import "FaviconDownload.h"
+#import "Feed+Ext.h"
+#import "FeedMeta+Ext.h"
+#import "NSURLRequest+Ext.h"
+
+@interface FaviconDownload()
+@property (nonatomic, weak) id<FaviconDownloadDelegate> delegate;
+@property (nonatomic, strong) FaviconDownloadBlock block;
+@property (nonatomic, weak) NSURLSessionTask *currentDownload;
+@property (nonatomic, assign) BOOL canceled;
+
+@property (nonatomic, assign) BOOL assertIsImageURL; // prohibit processing of HTML data
+@property (nonatomic, strong) NSURL *remoteURL; // remote absolute path
+@property (nonatomic, strong) NSURL *hostURL; // remote base domain
+@property (nonatomic, strong) NSURL *fileURL; // local location
+@end
+
+@implementation FaviconDownload
+
+//  ---------------------------------------------------------------
+// |  MARK: - Class methods
+//  ---------------------------------------------------------------
+
+/**
+ Start favicon download request on existing @c Feed object.
+ @note Will post a @c kNotificationFeedIconUpdated notification on success.
+ */
++ (instancetype)updateFeed:(Feed*)feed finally:(nullable os_block_t)block {
+	NSString *url = feed.link;
+	if (!url) url = feed.meta.url;
+	NSManagedObjectContext *moc = feed.managedObjectContext;
+	NSManagedObjectID *oid = feed.objectID;
+	return [[self withURL:url isImageURL:NO] startWithBlock:^(NSImage * _Nullable img, NSURL * _Nullable path) {
+		if (path) [(Feed*)[moc objectWithID:oid] setNewIcon:path];
+		if (block) block();
+	}];
+}
+
+/**
+ Instantiate new loader from URL.
+ @param flag If @c YES skip parsing of html.
+ */
++ (instancetype)withURL:(nonnull NSString*)urlStr isImageURL:(BOOL)flag {
+	FaviconDownload *this = [super new];
+	this.remoteURL = [NSURL URLWithString:urlStr];
+	this.assertIsImageURL = flag;
+	return this;
+}
+
+//  ---------------------------------------------------------------
+// |  MARK: - Actions
+//  ---------------------------------------------------------------
+
+/// Start download request and notify @c oberserver during the various steps.
+- (instancetype)startWithDelegate:(id<FaviconDownloadDelegate>)observer {
+	self.delegate = observer;
+	[self performSelectorInBackground:@selector(start) withObject:nil];
+	return self;
+}
+
+/// Start download request and notify @c block once finished.
+- (instancetype)startWithBlock:(nonnull FaviconDownloadBlock)block {
+	self.block = block;
+	[self performSelectorInBackground:@selector(start) withObject:nil];
+	return self;
+}
+
+/// Cancel running download task immediately. Will notify neither @c delegate nor @c block
+- (void)cancel {
+	self.canceled = YES;
+	self.delegate = nil;
+	self.block = nil;
+	[self.currentDownload cancel];
+}
+
+/// Called for both; delegate and block observer.
+- (void)start {
+	if (self.canceled)
+		return;
+	// Base URL part. E.g., https://stackoverflow.com/a/15897956/10616114 ==> https://stackoverflow.com/
+	self.hostURL = [[NSURL URLWithString:@"/" relativeToURL:self.remoteURL] absoluteURL];
+	self.assertIsImageURL ? [self continueWithImageDownload] : [self continueWithHTMLDownload];
+}
+
+/// Start request on HTML metadata and try parsing it. Will update @c remoteURL (@c nil on error)
+- (void)continueWithHTMLDownload {
+	if (self.canceled)
+		return;
+	self.remoteURL = nil;
+	self.currentDownload = [[NSURLRequest requestWithURL:self.hostURL] dataTask:^(NSData * _Nullable htmlData, NSError * _Nullable error, NSHTTPURLResponse *response) {
+		if (self.canceled)
+			return;
+		if (htmlData) {
+			// TODO: use session delegate to stop download after <head>
+			RSXMLData *xml = [[RSXMLData alloc] initWithData:htmlData url:response.URL];
+			RSHTMLMetadataParser *parser = [RSHTMLMetadataParser parserWithXMLData:xml];
+			RSHTMLMetadata *meta = [parser parseSync:&error];
+			if (error) meta = nil;
+			NSString *u = [FaviconDownload urlForMetadata:meta];
+			if (u) self.remoteURL = [NSURL URLWithString:u];
+		}
+		[self continueWithImageDownload];
+	}];
+}
+
+/// Choose action based on whether @c .remoteURL is set.
+- (void)continueWithImageDownload {
+	if (self.canceled)
+		return;
+	self.remoteURL ? [self loadImageFromRemoteURL] : [self loadImageFromDefaultLocation];
+}
+
+/// Download image from default location @c /favicon.ico
+- (void)loadImageFromDefaultLocation {
+	self.remoteURL = [self.hostURL URLByAppendingPathComponent:@"favicon.ico"];
+	self.hostURL = nil; // prevent recursion in loadImageFromRemoteURL
+	[self loadImageFromRemoteURL];
+}
+
+/// Start download of favicon whether from already parsed favicon URL or default location.
+- (void)loadImageFromRemoteURL {
+	if (self.canceled)
+		return;
+	self.currentDownload = [[NSURLRequest requestWithURL:self.remoteURL] downloadTask:^(NSURL * _Nullable path, NSError * _Nullable error) {
+		if (error) path = nil; // will also nullify img
+		NSImage *img = path ? [[NSImage alloc] initByReferencingURL:path] : nil;
+		if (img.valid) {
+			NSString *tmp = NSProcessInfo.processInfo.globallyUniqueString;
+			NSURL *dest = [path URLByDeletingLastPathComponent];
+			dest = [dest URLByAppendingPathComponent:tmp isDirectory:NO];
+			// move image to temporary destination, otherwise dataTask: will delete it.
+			[[NSFileManager defaultManager] moveItemAtURL:path toURL:dest error:nil];
+			self.fileURL = dest;
+		} else if (self.hostURL) {
+			[self loadImageFromDefaultLocation]; // starts a new request
+			return;
+		}
+		[self finishAndNotify];
+	}];
+}
+
+/// Called after trying all favicon URLs. May be @c nil if none of the URLs were successful.
+- (void)finishAndNotify {
+	if (self.canceled)
+		return;
+	NSURL *path = self.fileURL;
+	NSImage *img = [[NSImage alloc] initByReferencingURL:path];
+	if (!img.valid) { path = nil; img = nil; }
+#ifdef DEBUG
+	printf("ICON %1.0fx%1.0f %s\n", img.size.width, img.size.height, self.remoteURL.absoluteString.UTF8String);
+	printf(" ↳ %s\n", path.absoluteString.UTF8String);
+#endif
+	dispatch_async(dispatch_get_main_queue(), ^{
+		[self.delegate faviconDownload:self didFinish:path];
+		if (self.block) { self.block(img, path); self.block = nil; }
+	});
+}
+
+//  ---------------------------------------------------------------
+// |  MARK: - Extract from HTML metadata
+//  ---------------------------------------------------------------
+
+/// Extract favicon URL from parsed HTML metadata.
++ (nullable NSString*)urlForMetadata:(RSHTMLMetadata*)meta {
+	if (!meta) return nil;
+	
+	double bestScore = DBL_MAX;
+	NSString *iconURL = nil;
+	if (meta.faviconLink.length > 0) {
+		bestScore = ScoreIcon(nil);
+		iconURL = meta.faviconLink; // Replaced below if size is between 18 and 56
+	}
+	if (meta.iconLinks.count > 0) {
+		for (RSHTMLMetadataIconLink *icon in meta.iconLinks) {
+			double currentScore = ScoreIcon(icon);
+			if (currentScore < bestScore) {
+				bestScore = currentScore;
+				iconURL = icon.link;
+			}
+		}
+		if (!iconURL) // return first, even if all items in list have size 0
+			return meta.iconLinks.firstObject.link;
+	}
+	return iconURL;
+}
+
+/// Find icon with closest matching size 32x32 (lower score means better match)
+static double ScoreIcon(RSHTMLMetadataIconLink *icon) {
+	if ([icon.sizes isEqualToString:@"any"])
+		return DBL_MAX; // exclude svg
+	CGSize size = [icon getSize];
+	double area = size.width * size.height;
+	if (area <= 0) {
+		if ([icon.title hasPrefix:@"apple-touch-icon"])
+			area = 180 * 180; // https://webhint.io/docs/user-guide/hints/hint-apple-touch-icons/
+		else
+			area = 18 * 18; // Size could be 16, 32, or 48. Assuming its better than 16px.
+	}
+	double match = log10(area) - log10(32 * 32);
+	return fabs(match) + (match < 0 ? 1e-5 : 0); // slightly prefer larger icons (64px over 16px)
+}
+
+@end

baRSS/Feed Import/FeedDownload.h

@@ -0,0 +1,63 @@
+//
+//  The MIT License (MIT)
+//  Copyright (c) 2019 Oleg Geier
+//
+//  Permission is hereby granted, free of charge, to any person obtaining a copy of
+//  this software and associated documentation files (the "Software"), to deal in
+//  the Software without restriction, including without limitation the rights to
+//  use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
+//  of the Software, and to permit persons to whom the Software is furnished to do
+//  so, subject to the following conditions:
+//
+//  The above copyright notice and this permission notice shall be included in all
+//  copies or substantial portions of the Software.
+//
+//  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+//  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+//  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+//  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+//  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+//  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+//  SOFTWARE.
+
+@import Cocoa;
+@class RSParsedFeed, RSHTMLMetadataFeedLink, Feed, FaviconDownload;
+@protocol FeedDownloadDelegate;
+
+/**
+ All properties will be parsed and stored in local variables.
+ This will avoid unnecessary core data operations if user decides to cancel the edit.
+ */
+@interface FeedDownload : NSObject
+@property (readonly, nonnull) NSURLRequest *request;
+@property (readonly, nullable) NSHTTPURLResponse* response;
+@property (readonly, nullable) RSParsedFeed *xmlfeed;
+@property (readonly, nullable) NSError *error;
+@property (readonly, nullable) NSString *faviconURL;
+
+typedef void (^FeedDownloadBlock)(FeedDownload *sender);
+
+// Instantiation methods
++ (instancetype)withURL:(NSString*)url;
++ (instancetype)withFeed:(Feed*)feed forced:(BOOL)flag;
+// Actions
+- (instancetype)startWithDelegate:(id<FeedDownloadDelegate>)delegate;
+- (instancetype)startWithBlock:(nonnull FeedDownloadBlock)block;
+- (void)cancel;
+- (BOOL)copyValuesTo:(nonnull Feed*)feed ignoreError:(BOOL)flag;
+// Getter
+- (FaviconDownload*)faviconDownload;
+@end
+
+
+
+/// Protocol for handling an in memory download
+@protocol FeedDownloadDelegate <NSObject>
+@optional
+/// Delegate must return chosen URL. If not implemented, the first URL will be used.
+- (NSString*)feedDownload:(FeedDownload*)sender selectFeedFromList:(NSArray<RSHTMLMetadataFeedLink*>*)list;
+/// Only called if an URL redirect occured.
+- (void)feedDownload:(FeedDownload*)sender urlRedirected:(NSString*)newURL;
+/// Called after xml data is loaded and parsed. Called on error, but not if download is cancled.
+- (void)feedDownloadDidFinish:(FeedDownload*)sender;
+@end

baRSS/Feed Import/FeedDownload.m

@@ -0,0 +1,223 @@
+//
+//  The MIT License (MIT)
+//  Copyright (c) 2019 Oleg Geier
+//
+//  Permission is hereby granted, free of charge, to any person obtaining a copy of
+//  this software and associated documentation files (the "Software"), to deal in
+//  the Software without restriction, including without limitation the rights to
+//  use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
+//  of the Software, and to permit persons to whom the Software is furnished to do
+//  so, subject to the following conditions:
+//
+//  The above copyright notice and this permission notice shall be included in all
+//  copies or substantial portions of the Software.
+//
+//  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+//  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+//  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+//  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+//  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+//  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+//  SOFTWARE.
+
+@import RSXML;
+#import "FeedDownload.h"
+#import "FaviconDownload.h"
+#import "Feed+Ext.h"
+#import "FeedMeta+Ext.h"
+#import "NSURLRequest+Ext.h"
+
+@interface FeedDownload()
+@property (nonatomic, assign) BOOL respondToSelectFeed, respondToRedirect, respondToEnd;
+@property (nonatomic, weak) id<FeedDownloadDelegate> delegate;
+@property (nonatomic, strong) FeedDownloadBlock block;
+@property (nonatomic, weak) NSURLSessionTask *currentDownload;
+@property (nonatomic, assign) BOOL canceled;
+
+@property (nonatomic, assign) BOOL assertIsFeedURL; // prohibit processing of HTML data
+@property (nonatomic, strong) NSURLRequest *request;
+@property (nonatomic, strong) NSHTTPURLResponse* response;
+@property (nonatomic, strong) RSParsedFeed *xmlfeed;
+@property (nonatomic, strong) NSError *error;
+@property (nonatomic, strong) NSString *faviconURL;
+@end
+
+@implementation FeedDownload
+
+//  ---------------------------------------------------------------
+// |  MARK: - Class methods
+//  ---------------------------------------------------------------
+
+/// @return New instance with plain @c url request.
++ (instancetype)withURL:(NSString*)url {
+	FeedDownload *this = [FeedDownload new];
+	this.request = [NSURLRequest withURL:url];
+	return this;
+}
+
+/// @return New instance using existing @c feed as template. Will reuse @c Etag and @c Last-modified headers.
++ (instancetype)withFeed:(Feed*)feed forced:(BOOL)flag {
+	FeedMeta *m = feed.meta;
+	NSMutableURLRequest *req = [NSMutableURLRequest withURL:m.url];
+	if (!flag) // any request that is not forced, is a background update
+		req.networkServiceType = NSURLNetworkServiceTypeBackground;
+	if (feed.articles.count > 0) { // dont use cache if feed is broken
+		// Both fields should be send (if server provides both) RFC: https://tools.ietf.org/html/rfc7232#section-2.4
+		if (m.etag.length > 0)
+			[req setValue:[m.etag stringByReplacingOccurrencesOfString:@"-gzip" withString:@""] forHTTPHeaderField:@"If-None-Match"]; // ETag
+		if (m.modified.length > 0)
+			[req setValue:m.modified forHTTPHeaderField:@"If-Modified-Since"];
+	}
+	FeedDownload *this = [FeedDownload new];
+	this.assertIsFeedURL = YES;
+	this.request = req;
+	return this;
+}
+
+//  ---------------------------------------------------------------
+// |  MARK: - Getter & Setter
+//  ---------------------------------------------------------------
+
+/// Set delegate and check what methods are implemented.
+- (void)setDelegate:(id<FeedDownloadDelegate>)observer {
+	_delegate = observer;
+	_respondToSelectFeed = [observer respondsToSelector:@selector(feedDownload:selectFeedFromList:)];
+	_respondToRedirect = [observer respondsToSelector:@selector(feedDownload:urlRedirected:)];
+	_respondToEnd = [observer respondsToSelector:@selector(feedDownloadDidFinish:)];
+}
+
+/// @return Initialize @c FaviconDownload instance. Will reuse favicon url from HTML parsing.
+- (FaviconDownload*)faviconDownload {
+	if (self.faviconURL.length > 0) // favicon url already found, nice job
+		return [FaviconDownload withURL:self.faviconURL isImageURL:YES];
+	
+	NSString *url = self.xmlfeed.link; // does only work for status != 304
+	if (!url) url = self.response.URL.absoluteString;
+	return [FaviconDownload withURL:url isImageURL:NO];
+}
+
+//  ---------------------------------------------------------------
+// |  MARK: - Actions
+//  ---------------------------------------------------------------
+
+/// Start download request and use @c delegate as callback notifier.
+- (instancetype)startWithDelegate:(id<FeedDownloadDelegate>)delegate {
+	self.delegate = delegate;
+	[self downloadSource:self.request];
+	return self;
+}
+
+/// Start download request and use @c block as callback notifier.
+- (instancetype)startWithBlock:(nonnull FeedDownloadBlock)block {
+	self.block = block;
+	[self downloadSource:self.request];
+	return self;
+}
+
+/// Cancel running download task without notice. Will notify neither @c delegate nor @c block
+- (void)cancel {
+	self.canceled = YES;
+	self.delegate = nil;
+	self.block = nil;
+	[self.currentDownload cancel];
+}
+
+/// Take the @c urlStr and run a download @c dataTask: on it. Auto-detect if data is HTML or feed.
+- (void)downloadSource:(NSURLRequest*)request {
+	self.currentDownload = [request dataTask:^(NSData * _Nullable data, NSError * _Nullable error, NSHTTPURLResponse *response) {
+		self.error = error;
+		self.response = response;
+		if (!data) { // data = nil if (error || 304)
+			[self performSelectorOnMainThread:@selector(finishAndNotify) withObject:nil waitUntilDone:NO];
+			return;
+		}
+		RSXMLData *xml = [[RSXMLData alloc] initWithData:data url:response.URL];
+		if (!self.assertIsFeedURL && [xml.parserClass isHTMLParser])
+			[self processXMLDataHTML:xml];
+		else
+			[self processXMLDataFeed:xml];
+	}];
+}
+
+/// The downloaded source seems to be HTML data, lets parse it with @c RSXML @c RSHTMLMetadataParser
+- (void)processXMLDataHTML:(RSXMLData*)xml {
+	RSHTMLMetadataParser *parser = [RSHTMLMetadataParser parserWithXMLData:xml];
+	[parser parseAsync:^(RSHTMLMetadata * _Nullable meta, NSError * _Nullable error) {
+		if (error) {
+			self.error = error;
+		} else if (!meta || meta.feedLinks.count == 0) {
+			self.error = RSXMLMakeErrorWrongParser(RSXMLErrorExpectingFeed, RSXMLErrorExpectingHTML, xml.url);
+		} else {
+			self.faviconURL = [FaviconDownload urlForMetadata:meta]; // we can re-use favicon url if we find one
+			NSString *chosenURL = meta.feedLinks.firstObject.link;
+			if (self.respondToSelectFeed && meta.feedLinks.count > 1)
+				chosenURL = [self.delegate feedDownload:self selectFeedFromList:meta.feedLinks];
+			
+			if (chosenURL.length > 0) {
+				self.assertIsFeedURL = YES;
+				// Feeds like https://news.ycombinator.com/ return 503 if URLs are requested too rapidly
+				//CFRunLoopRunInMode(kCFRunLoopDefaultMode, 1.0, false); // Non-blocking sleep (1s)
+				[self downloadSource:[NSURLRequest withURL:chosenURL]];
+				return;
+			} else { // User canceled operation, show appropriate error message
+				NSDictionary *info = @{ NSLocalizedDescriptionKey: NSLocalizedString(@"Operation canceled.", nil) };
+				self.error = [NSError errorWithDomain:NSURLErrorDomain code:NSURLErrorCancelled userInfo:info];
+			}
+		}
+		[self finishAndNotify];
+	}];
+}
+
+/// The downloaded source seems to be proper feed data, lets parse it with @c RSXML @c RSFeedParser
+- (void)processXMLDataFeed:(RSXMLData*)xml {
+	RSFeedParser *parser = [RSFeedParser parserWithXMLData:xml];
+	parser.dontStopOnLowerAsciiBytes = YES;
+	[parser parseAsync:^(RSParsedFeed * _Nullable parsedDocument, NSError * _Nullable error) {
+		self.error = error;
+		self.xmlfeed = parsedDocument;
+		[self finishAndNotify];
+	}];
+}
+
+/// Check if @c responseURL @c != @c requestURL
+- (void)checkRedirectAndNotify {
+	NSString *responseURL = self.response.URL.absoluteString;
+	if (responseURL.length > 0 && ![responseURL isEqualToString:self.request.URL.absoluteString]) {
+		if (self.respondToRedirect) [self.delegate feedDownload:self urlRedirected:responseURL];
+	}
+}
+
+/// Called when feed download finished or failed, but not if canceled. Will notify @c delegate .
+- (void)finishAndNotify {
+	if (self.canceled)
+		return;
+	[self checkRedirectAndNotify];
+	// notify observer
+	if (self.respondToEnd) [self.delegate feedDownloadDidFinish:self];
+	if (self.block) { self.block(self); self.block = nil; }
+}
+
+/**
+ Persist in memory object by copying all attributes to permanent core data storage.
+
+ @param flag If @c YES then @c FeedGroup won't increase the error count for the feed.
+             Feed will be scheduled as soon as the user reconnects to the internet.
+ @return @c YES if downloaded feed contains at least one article. ( @c 304 returns @c NO )
+ */
+- (BOOL)copyValuesTo:(nonnull Feed*)feed ignoreError:(BOOL)flag {
+	if (!flag && self.error) // Increase error count and schedule next update.
+		[feed.meta setErrorAndPostponeSchedule];
+	else if (self.response) // Update Etag & Last modified and schedule next update.
+		[feed.meta setSucessfulWithResponse:self.response];
+	else // Update URL but keep schedule (e.g., error while adding feed should auto-try once reconnected)
+		[feed.meta setUrlIfChanged:self.request.URL.absoluteString];
+	
+	// If feed is broken indicate that feed will not be updated
+	if (!self.xmlfeed || self.xmlfeed.articles.count == 0)
+		return NO;
+	// Else: Update stored articles and indicate that feed was updated
+	[feed updateWithRSS:self.xmlfeed postUnreadCountChange:YES];
+	return YES;
+}
+
+@end

baRSS/Feed Import/OpmlFile.m

@@ -32,7 +32,7 @@
 #pragma mark - Helper
 
 /// Loop over all subviews and find the @c NSButton that is selected.
-NS_INLINE NSInteger RadioGroupSelection(NSView *view) {
+static NSInteger RadioGroupSelection(NSView *view) {
 	for (NSButton *btn in view.subviews) {
 		if ([btn isKindOfClass:[NSButton class]] && btn.state == NSControlStateValueOn) {
 			return btn.tag;
@@ -93,8 +93,7 @@ NS_INLINE NSInteger RadioGroupSelection(NSView *view) {
 - (void)enumerateFiles:(NSArray<NSURL*>*)files withBlock:(void(^)(RSOPMLItem *item))block finally:(nullable dispatch_block_t)finally {
 	dispatch_group_t group = dispatch_group_create();
 	for (NSURL *url in files) {
-		if (finally) dispatch_group_enter(group);
+		dispatch_group_enter(group);
-		
 		NSData *data = [NSData dataWithContentsOfURL:url];
 		RSXMLData *xml = [[RSXMLData alloc] initWithData:data url:url];
 		RSOPMLParser *parser = [RSOPMLParser parserWithXMLData:xml];
@@ -106,7 +105,7 @@ NS_INLINE NSInteger RadioGroupSelection(NSView *view) {
 					block(itm);
 				}
 			}
-			if (finally) dispatch_group_leave(group);
+			dispatch_group_leave(group);
 		}];
 	}
 	if (finally) dispatch_group_notify(group, dispatch_get_main_queue(), finally);
@@ -251,9 +250,7 @@ NS_INLINE NSInteger RadioGroupSelection(NSView *view) {
 		NSData *xml = [doc XMLDataWithOptions:NSXMLNodePreserveAttributeOrder | NSXMLNodePrettyPrint];
 		[xml writeToURL:url options:NSDataWritingAtomic error:&error];
 	}
-	if (error) {
+	if (error) [NSApp presentError:error];
-		[NSApp presentError:error];
-	}
 	return error;
 }
 
@@ -293,8 +290,8 @@ NS_INLINE NSInteger RadioGroupSelection(NSView *view) {
 		// dont add group node if hierarchical == NO
 		NSXMLElement *outline = [NSXMLElement elementWithName:@"outline"];
 		[parent addChild:outline];
-		[outline addAttribute:[NSXMLNode attributeWithName:OPMLTitleKey stringValue:item.name]];
+		[outline addAttribute:[NSXMLNode attributeWithName:OPMLTitleKey stringValue:item.anyName]];
-		[outline addAttribute:[NSXMLNode attributeWithName:OPMLTextKey stringValue:item.name]];
+		[outline addAttribute:[NSXMLNode attributeWithName:OPMLTextKey stringValue:item.anyName]];
 		
 		if (item.type == SEPARATOR) {
 			[outline addAttribute:[NSXMLNode attributeWithName:@"separator" stringValue:@"true"]]; // baRSS specific

baRSS/Feed Import/UpdateScheduler.h

@@ -37,7 +37,11 @@
 // Scheduling
 + (void)scheduleNextFeed;
 + (void)forceUpdateAllFeeds;
-+ (void)downloadList:(NSArray<Feed*>*)list background:(BOOL)flag finally:(nullable os_block_t)block;
++ (void)downloadList:(NSArray<Feed*>*)list userInitiated:(BOOL)flag finally:(nullable os_block_t)block;
++ (void)updateAllFavicons;
+// Auto Download & Parse Feed URL
++ (void)autoDownloadAndParseURL:(NSString*)url;
++ (void)autoDownloadAndParseUpdateURL;
 // Register for network change notifications
 + (void)registerNetworkChangeNotification;
 + (void)unregisterNetworkChangeNotification;

baRSS/Feed Import/UpdateScheduler.m

@@ -22,24 +22,33 @@
 
 @import SystemConfiguration;
 #import "UpdateScheduler.h"
-#import "WebFeed.h"
 #import "Constants.h"
 #import "StoreCoordinator.h"
 #import "NSDate+Ext.h"
 
+#import "FeedDownload.h"
+#import "FaviconDownload.h"
+#import "Feed+Ext.h"
+#import "FeedMeta+Ext.h"
+#import "FeedGroup+Ext.h"
+
+#include <stdatomic.h>
+
 static NSTimer *_timer;
 static SCNetworkReachabilityRef _reachability = NULL;
 static BOOL _isReachable = YES;
 static BOOL _updatePaused = NO;
 static BOOL _nextUpdateIsForced = NO;
-
+static _Atomic(NSUInteger) _queueSize = 0;
 
 @implementation UpdateScheduler
 
-#pragma mark - User Interaction
+// ################################################################
+// #  MARK: - Getter & Setter -
+// ################################################################
 
 /// @return Number of feeds being currently downloaded.
-+ (NSUInteger)feedsInQueue { return [WebFeed feedsInQueue]; }
++ (NSUInteger)feedsInQueue { return _queueSize; }
 
 /// @return Date when background update will fire. If updates are paused, date is @c distantFuture.
 + (NSDate *)dateScheduled { return _timer.fireDate; }
@@ -48,7 +57,7 @@ static BOOL _nextUpdateIsForced = NO;
 + (BOOL)allowNetworkConnection { return (_isReachable && !_updatePaused); }
 
 /// @return @c YES if batch update is running
-+ (BOOL)isUpdating { return [WebFeed feedsInQueue] > 0; }
++ (BOOL)isUpdating { return _queueSize > 0; }
 
 /// @return @c YES if update is paused by user.
 + (BOOL)isPaused { return _updatePaused; }
@@ -78,7 +87,7 @@ static BOOL _nextUpdateIsForced = NO;
 
 /// Update status. 'Updating X feeds …' or empty string if not updating.
 + (NSString*)updatingXFeeds {
-	NSUInteger c = [WebFeed feedsInQueue];
+	NSUInteger c = _queueSize;
 	switch (c) {
 		case 0:  return @"";
 		case 1:  return NSLocalizedString(@"Updating 1 feed …", nil);
@@ -86,17 +95,15 @@ static BOOL _nextUpdateIsForced = NO;
 	}
 }
 
+// ################################################################
+// #  MARK: - Schedule Timer Actions -
+// ################################################################
 
-#pragma mark - Update Feed Timer
+/// Get date of next up feed and start the timer.
-
-
-/**
- Get date of next up feed and start the timer.
- */
 + (void)scheduleNextFeed {
 	if (![self allowNetworkConnection]) // timer will restart once connection exists
 		return;
-	if ([WebFeed feedsInQueue] > 0) // assume every update ends with scheduleNextFeed
+	if (_queueSize > 0) // assume every update ends with scheduleNextFeed
 		return; // skip until called again
 	NSDate *nextTime = [StoreCoordinator nextScheduledUpdate]; // if nextTime = nil, then no feeds to update
 	if (nextTime && [nextTime timeIntervalSinceNow] < 1) { // mostly, if app was closed for a long time
@@ -105,9 +112,7 @@ static BOOL _nextUpdateIsForced = NO;
 	[self scheduleTimer:nextTime];
 }
 
-/**
+/// Start download of all feeds (immediatelly) regardless of @c .scheduled property.
- Start download of all feeds (immediatelly) regardless of @c .scheduled property.
- */
 + (void)forceUpdateAllFeeds {
 	if (![self allowNetworkConnection]) // timer will restart once connection exists
 		return;
@@ -118,7 +123,7 @@ static BOOL _nextUpdateIsForced = NO;
 /**
  Set new @c .fireDate and @c .tolerance for update timer.
 
- @param nextTime If @c nil timer will be disabled with a @c .fireDate very far in the future.
+ @param nextTime If @c nil disable timer and set @c .fireDate to distant future.
  */
 + (void)scheduleTimer:(NSDate*)nextTime {
 	static dispatch_once_t onceToken;
@@ -134,9 +139,7 @@ static BOOL _nextUpdateIsForced = NO;
 	PostNotification(kNotificationScheduleTimerChanged, nil);
 }
 
-/**
+/// Called when schedule timer runs out (earliest @c .schedule date). Or if forced by user.
- Called when schedule timer runs out (earliest @c .schedule date). Or if forced by user request.
- */
 + (void)updateTimerCallback {
 #ifdef DEBUG
 	NSLog(@"fired");
@@ -145,35 +148,115 @@ static BOOL _nextUpdateIsForced = NO;
 	_nextUpdateIsForced = NO;
 	
 	NSManagedObjectContext *moc = [StoreCoordinator createChildContext];
-	NSArray<Feed*> *list = [StoreCoordinator getListOfFeedsThatNeedUpdate:updateAll inContext:moc];
+	NSArray<Feed*> *list = [StoreCoordinator listOfFeedsThatNeedUpdate:updateAll inContext:moc];
 	//NSAssert(list.count > 0, @"ERROR: Something went wrong, timer fired too early.");
 	
-	[self downloadList:list background:!updateAll finally:^{
+	[self downloadList:list userInitiated:updateAll finally:^{
 		[StoreCoordinator saveContext:moc andParent:YES]; // save parents too ...
 		[moc reset];
 		[self scheduleNextFeed]; // always reset the timer
 	}];
 }
 
-/// Download list of feeds. Either silently in background or in foreground with alerts.
+// ################################################################
-+ (void)downloadList:(NSArray<Feed*>*)list background:(BOOL)flag finally:(nullable os_block_t)block {
+// #  MARK: - Download Actions -
+// ################################################################
+
+/// Perform @c FaviconDownload on all core data @c Feed entries.
++ (void)updateAllFavicons {
+	NSManagedObjectContext *moc = [StoreCoordinator createChildContext];
+	for (Feed *f in [StoreCoordinator listOfFeedsThatNeedUpdate:YES inContext:moc])
+		[FaviconDownload updateFeed:f finally:nil];
+	[moc reset];
+}
+
+/// Download list of feeds. Either silently in background or with alerts in foreground.
++ (void)downloadList:(NSArray<Feed*>*)list userInitiated:(BOOL)flag finally:(nullable os_block_t)block {
 	if (![self allowNetworkConnection]) {
 		if (block) block();
-	} else if (flag) {
+		return;
-		[WebFeed batchDownloadFeeds:list showErrorAlert:NO finally:block];
+	}
-	} else {
+	// Else: batch download
-		// TODO: add undo grouping?
+	atomic_fetch_add_explicit(&_queueSize, list.count, memory_order_relaxed);
-		[WebFeed setRequestsAreUrgent:YES];
+	PostNotification(kNotificationBackgroundUpdateInProgress, @(_queueSize));
-		[WebFeed batchDownloadFeeds:list showErrorAlert:YES finally:^{
+	dispatch_group_t group = dispatch_group_create();
-			[WebFeed setRequestsAreUrgent:NO];
+	for (Feed *f in list) {
-			if (block) block();
+		dispatch_group_enter(group);
+		[self updateFeed:f alert:flag isForced:flag finally:^{
+			atomic_fetch_sub_explicit(&_queueSize, 1, memory_order_relaxed);
+			PostNotification(kNotificationBackgroundUpdateInProgress, @(_queueSize));
+			dispatch_group_leave(group);
 		}];
 	}
+	if (block) dispatch_group_notify(group, dispatch_get_main_queue(), block);
 }
 
+/// Helper method to show modal error alert
+static inline void AlertDownloadError(NSError *err, NSString *url) {
+	NSAlert *alertPopup = [NSAlert alertWithError:err];
+	alertPopup.informativeText = [NSString stringWithFormat:@"Error loading source: %@", url];
+	[alertPopup runModal];
+}
 
-#pragma mark - Network Connection & Reachability
+/**
+ Start download request with existing @c Feed object. Reuses etag and modified headers (unless articles count is 0).
+ @note Will post a @c kNotificationArticlesUpdated notification if download was successful and status code is @b not 304.
+ */
++ (void)updateFeed:(Feed*)feed alert:(BOOL)alert isForced:(BOOL)forced finally:(nullable os_block_t)block {
+	NSManagedObjectContext *moc = feed.managedObjectContext;
+	NSManagedObjectID *oid = feed.objectID;
+	[[FeedDownload withFeed:feed forced:forced] startWithBlock:^(FeedDownload *mem) {
+		if (alert && mem.error) // but still copy values for error count increment
+			AlertDownloadError(mem.error, mem.request.URL.absoluteString);
+		Feed *f = [moc objectWithID:oid];
+		BOOL recentlyAdded = (f.articles.count == 0); // before copy values
+		BOOL downloadIcon = (!f.hasIcon && (recentlyAdded || forced));
+		BOOL needsNotification = [mem copyValuesTo:f ignoreError:NO];
+		[StoreCoordinator saveContext:moc andParent:YES];
+		if (needsNotification)
+			PostNotification(kNotificationArticlesUpdated, oid);
+		if (downloadIcon && !mem.error) {
+			[FaviconDownload updateFeed:f finally:block];
+		} else if (block) block(); // always call block(); with or without favicon download
+	}];
+}
 
+/**
+ Download feed at url and append to persistent store in root folder. On error present user modal alert.
+ Creates new @c FeedGroup, @c Feed, @c FeedMeta and @c FeedArticle instances and saves them to the persistent store.
+ */
++ (void)autoDownloadAndParseURL:(NSString*)url addAnyway:(BOOL)flag name:(nullable NSString*)title refresh:(int32_t)interval {
+	[[FeedDownload withURL:url] startWithBlock:^(FeedDownload *mem) {
+		if (!flag && mem.error) {
+			AlertDownloadError(mem.error, url);
+			return;
+		}
+		NSManagedObjectContext *moc = [StoreCoordinator createChildContext];
+		FeedGroup *fg = [FeedGroup appendToRoot:FEED inContext:moc];
+		[fg setNameIfChanged:title];
+		[fg.feed.meta setRefreshIfChanged:interval];
+		[mem copyValuesTo:fg.feed ignoreError:YES];
+		[StoreCoordinator saveContext:moc andParent:YES];
+		PostNotification(kNotificationFeedGroupInserted, fg.objectID);
+		if (!mem.error) [FaviconDownload updateFeed:fg.feed finally:nil];
+		[moc reset];
+		[UpdateScheduler scheduleNextFeed];
+	}];
+}
+
+/// Download and process feed url. Auto update feed title with an update interval of 30 min.
++ (void)autoDownloadAndParseURL:(NSString*)url {
+	[self autoDownloadAndParseURL:url addAnyway:NO name:nil refresh:kDefaultFeedRefreshInterval];
+}
+
+/// Insert Github URL for version releases with update interval 2 days and rename @c FeedGroup item.
++ (void)autoDownloadAndParseUpdateURL {
+	[self autoDownloadAndParseURL:versionUpdateURL addAnyway:YES name:NSLocalizedString(@"baRSS releases", nil) refresh:2 * TimeUnitDays];
+}
+
+// ################################################################
+// #  MARK: - Network Connection & Reachability -
+// ################################################################
 
 /// Set callback on @c self to listen for network reachability changes.
 + (void)registerNetworkChangeNotification {

baRSS/Feed Import/WebFeed.h

@@ -1,52 +0,0 @@
-//
-//  The MIT License (MIT)
-//  Copyright (c) 2018 Oleg Geier
-//
-//  Permission is hereby granted, free of charge, to any person obtaining a copy of
-//  this software and associated documentation files (the "Software"), to deal in
-//  the Software without restriction, including without limitation the rights to
-//  use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
-//  of the Software, and to permit persons to whom the Software is furnished to do
-//  so, subject to the following conditions:
-//
-//  The above copyright notice and this permission notice shall be included in all
-//  copies or substantial portions of the Software.
-//
-//  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-//  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-//  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
-//  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-//  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-//  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
-//  SOFTWARE.
-
-@import Cocoa;
-@import RSXML;
-@class Feed;
-
-@interface WebFeed : NSObject
-@property (class, readonly) NSUInteger feedsInQueue;
-
-+ (void)setRequestsAreUrgent:(BOOL)flag;
-// Downloading
-+ (void)newFeed:(NSString *)urlStr askUser:(nonnull NSString*(^)(RSHTMLMetadata *meta))askUser block:(nonnull void(^)(RSParsedFeed *parsed, NSError *error, NSHTTPURLResponse *response))block;
-+ (void)autoDownloadAndParseURL:(NSString*)urlStr addAnyway:(BOOL)flag modify:(nullable void(^)(Feed *feed))block;
-+ (void)autoDownloadAndParseUpdateURL;
-+ (void)batchDownloadFeeds:(NSArray<Feed*>*)list showErrorAlert:(BOOL)alert finally:(nullable os_block_t)block;
-// Favicon image download
-+ (void)downloadFavicon:(NSString*)urlStr finished:(void(^)(NSImage * _Nullable img))block;
-+ (void)downloadImage:(NSString*)url finished:(void(^)(NSImage * _Nullable img))block;
-+ (nullable NSString*)faviconUrlForMetadata:(RSHTMLMetadata*)meta;
-@end
-
-
-/*
- Developer Tip, error logs see:
- 
- Task <..> HTTP load failed (error code: -1003 [12:8])
- Task <..> finished with error - code: -1003
- ==> NSURLErrorCannotFindHost in #import <Foundation/NSURLError.h>
- 
- TIC TCP Conn Failed [21:0x1d417fb00]: 1:65 Err(65)
- ==> EHOSTUNREACH in #import <sys/errno.h>
- */

baRSS/Feed Import/WebFeed.m

@@ -1,409 +0,0 @@
-//
-//  The MIT License (MIT)
-//  Copyright (c) 2018 Oleg Geier
-//
-//  Permission is hereby granted, free of charge, to any person obtaining a copy of
-//  this software and associated documentation files (the "Software"), to deal in
-//  the Software without restriction, including without limitation the rights to
-//  use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
-//  of the Software, and to permit persons to whom the Software is furnished to do
-//  so, subject to the following conditions:
-//
-//  The above copyright notice and this permission notice shall be included in all
-//  copies or substantial portions of the Software.
-//
-//  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-//  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-//  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
-//  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-//  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-//  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
-//  SOFTWARE.
-
-#import "WebFeed.h"
-#import "UpdateScheduler.h"
-#import "Constants.h"
-#import "StoreCoordinator.h"
-#import "Feed+Ext.h"
-#import "FeedMeta+Ext.h"
-#import "FeedGroup+Ext.h"
-#import "NSDate+Ext.h"
-#import "NSString+Ext.h"
-
-#include <stdatomic.h>
-
-static BOOL _requestsAreUrgent = NO;
-static _Atomic(NSUInteger) _queueSize = 0;
-
-@implementation WebFeed
-
-/// Disables @c NSURLNetworkServiceTypeBackground (ideally only temporarily)
-+ (void)setRequestsAreUrgent:(BOOL)flag { _requestsAreUrgent = flag; }
-
-/// @return Number of feeds being currently downloaded.
-+ (NSUInteger)feedsInQueue { return _queueSize; }
-
-
-#pragma mark - Request Generator
-
-
-/// @return Base URL part. E.g., https://stackoverflow.com/a/15897956/10616114 ==> https://stackoverflow.com/
-+ (NSURL*)hostURL:(NSString*)urlStr {
-	return [[NSURL URLWithString:@"/" relativeToURL:[self fixURL:urlStr]] absoluteURL];
-}
-
-/// Check if any scheme is set. If not, prepend 'http://'.
-+ (NSURL*)fixURL:(NSString*)urlStr {
-	NSURL *url = [NSURL URLWithString:urlStr];
-	if (!url.scheme) {
-		url = [NSURL URLWithString:[NSString stringWithFormat:@"http://%@", urlStr]]; // usually will redirect to https if necessary
-	}
-	return url;
-}
-
-/// @return New request with no caching policy and timeout interval of 30 seconds.
-+ (NSMutableURLRequest*)newRequestURL:(NSString*)urlStr {
-	return [NSMutableURLRequest requestWithURL:[self fixURL:urlStr]];
-}
-
-/// @return New request with etag and modified headers set (or not, if @c flag @c == @c YES ).
-+ (NSURLRequest*)newRequest:(FeedMeta*)meta ignoreCache:(BOOL)flag {
-	NSMutableURLRequest *req = [self newRequestURL:meta.url];
-	if (!flag) {
-		// Both fields should be sent (if server provides both) RFC: https://tools.ietf.org/html/rfc7232#section-2.4
-		if (meta.etag.length > 0) {
-			NSString *etag = [meta.etag stringByReplacingOccurrencesOfString:@"-gzip" withString:@""];
-			[req setValue:etag forHTTPHeaderField:@"If-None-Match"]; // ETag
-		}
-		if (meta.modified.length > 0)
-			[req setValue:meta.modified forHTTPHeaderField:@"If-Modified-Since"];
-	}
-	if (!_requestsAreUrgent) // any request that is not forced, is a background update
-		req.networkServiceType = NSURLNetworkServiceTypeBackground;
-	return req;
-}
-
-+ (NSURLSession*)nonCachingSession {
-	static NSURLSession *session = nil;
-	static dispatch_once_t onceToken;
-	dispatch_once(&onceToken, ^{
-		NSURLSessionConfiguration *conf = [NSURLSessionConfiguration defaultSessionConfiguration];
-		conf.HTTPCookieAcceptPolicy = NSHTTPCookieAcceptPolicyNever;
-		conf.HTTPShouldSetCookies = NO;
-		conf.HTTPCookieStorage = nil; // disables '~/Library/Cookies/'
-		conf.requestCachePolicy = NSURLRequestReloadIgnoringLocalCacheData;
-		conf.URLCache = nil; // disables '~/Library/Caches/de.relikd.baRSS/'
-		conf.HTTPAdditionalHeaders = @{ @"User-Agent": @"baRSS (macOS)",
-										@"Accept-Encoding": @"gzip" };
-		session = [NSURLSession sessionWithConfiguration:conf];
-	});
-	return session; // [NSURLSession sharedSession];
-}
-
-/// Helper method to start new @c NSURLSession. If @c (http.statusCode==304) then set @c data @c = @c nil.
-+ (void)asyncRequest:(NSURLRequest*)request block:(nonnull void(^)(NSData * _Nullable data, NSError * _Nullable error, NSHTTPURLResponse *response))block {
-	[[[self nonCachingSession] dataTaskWithRequest:request completionHandler:^(NSData * _Nullable data, NSURLResponse * _Nullable response, NSError * _Nullable error) {
-		NSHTTPURLResponse* httpResponse = (NSHTTPURLResponse*)response;
-		NSInteger status = [httpResponse statusCode];
-		if (error || status == 304) { // 304 Not Modified
-			data = nil;
-		} else if (status >= 500 && status < 600) { // 5xx Server Error
-			NSString *reason = [NSString stringWithFormat:NSLocalizedString(@"Server HTTP error %ld.\n––––\n%@", nil),
-								status, [NSString plainTextFromHTMLData:data]];
-			error = [NSError errorWithDomain:NSURLErrorDomain code:NSURLErrorBadServerResponse userInfo:@{NSLocalizedDescriptionKey: reason}];
-			data = nil;
-		}
-		block(data, error, httpResponse); // if status == 304, data & error nil
-	}] resume];
-}
-
-
-#pragma mark - Download RSS Feed
-
-
-/**
- Start download session of RSS or Atom feed, parse feed and return result on the main thread.
- 
- @param xmlBlock Called immediately after @c RSXMLData is initialized. E.g., to use this data as HTML parser.
-                 Return @c YES to to exit without calling @c feedBlock.
-                 If @c NO and @c err @c != @c nil skip feed parsing and call @c feedBlock(nil,err,response).
- @param feedBlock Called when parsing finished or an @c NSURL error occured.
-                  If content did not change (status code 304) both, error and result will be @c nil.
-                  Will be called on main thread.
- */
-+ (void)parseFeedRequest:(NSURLRequest*)request xmlBlock:(nullable BOOL(^)(RSXMLData *xml, NSError **err))xmlBlock feedBlock:(nonnull void(^)(RSParsedFeed *rss, NSError *error, NSHTTPURLResponse *response))feedBlock {
-	[self asyncRequest:request block:^(NSData * _Nullable data, NSError * _Nullable error, NSHTTPURLResponse *response) {
-		RSParsedFeed *result = nil;
-		if (data) { // data = nil if (error || 304)
-			RSXMLData *xml = [[RSXMLData alloc] initWithData:data url:response.URL];
-			if (xmlBlock && xmlBlock(xml, &error)) {
-				return;
-			}
-			if (!error) { // metaBlock may set error
-				RSFeedParser *parser = [RSFeedParser parserWithXMLData:xml];
-				parser.dontStopOnLowerAsciiBytes = YES;
-				result = [parser parseSync:&error];
-			}
-		}
-		dispatch_async(dispatch_get_main_queue(), ^{
-			feedBlock(result, error, response);
-		});
-	}];
-}
-
-/**
- Perform feed download request from URL alone. Not updating any @c Feed item.
- 
- @note @c askUser will not be called if url is XML already.
- 
- @param urlStr XML URL or HTTP URL that will be parsed to find feed URLs.
- @param askUser Use @c list to present user a list of detected feed URLs.
- @param block Called after webpage has been fully parsed (including html autodetect).
- */
-+ (void)newFeed:(NSString *)urlStr askUser:(nonnull NSString*(^)(RSHTMLMetadata *meta))askUser block:(nonnull void(^)(RSParsedFeed *parsed, NSError *error, NSHTTPURLResponse *response))block {
-	[self parseFeedRequest:[self newRequestURL:urlStr] xmlBlock:^BOOL(RSXMLData *xml, NSError **err) {
-		if (![xml.parserClass isHTMLParser])
-			return NO;
-		RSHTMLMetadataParser *parser = [RSHTMLMetadataParser parserWithXMLData:xml];
-		RSHTMLMetadata *parsedMeta = [parser parseSync:err];
-		if (*err)
-			return NO;
-		if (!parsedMeta || parsedMeta.feedLinks.count == 0) {
-			*err = RSXMLMakeErrorWrongParser(RSXMLErrorExpectingFeed, RSXMLErrorExpectingHTML, xml.url);
-			return NO;
-		}
-		__block NSString *chosenURL = nil;
-		dispatch_sync(dispatch_get_main_queue(), ^{ // sync! (thread is already in background)
-			chosenURL = askUser(parsedMeta);
-		});
-		if (!chosenURL || chosenURL.length == 0) { // User canceled operation, show appropriate error message
-			NSString *reason = NSLocalizedString(@"Operation canceled.", nil);
-			*err = [NSError errorWithDomain:NSURLErrorDomain code:NSURLErrorCancelled userInfo:@{NSLocalizedDescriptionKey: reason}];
-			return NO;
-		}
-		[self parseFeedRequest:[self newRequestURL:chosenURL] xmlBlock:nil feedBlock:block];
-		return YES;
-	} feedBlock:block];
-}
-
-/**
- Start download request with existing @c Feed object. Reuses etag and modified headers (unless articles count is 0).
- 
- @note Will post a @c kNotificationFeedUpdated notification if download was successful and @b not status code 304.
- 
- @param alert If @c YES display Error Popup to user.
- @param block Parameter @c success is only @c YES if download was successful or if status code is 304 (not modified).
- */
-+ (void)backgroundUpdateFeed:(Feed*)feed showErrorAlert:(BOOL)alert finally:(nullable void(^)(BOOL success))block {
-	NSManagedObjectID *oid = feed.objectID;
-	NSManagedObjectContext *moc = feed.managedObjectContext;
-	NSURLRequest *req = [self newRequest:feed.meta ignoreCache:(feed.articles.count == 0)];
-	NSString *reqURL = req.URL.absoluteString;
-	[self parseFeedRequest:req xmlBlock:nil feedBlock:^(RSParsedFeed *rss, NSError *error, NSHTTPURLResponse *response) {
-		Feed *f = [moc objectWithID:oid];
-		BOOL success = NO;
-		BOOL needsNotification = NO;
-		if (error) {
-			if (alert) {
-				NSAlert *alertPopup = [NSAlert alertWithError:error];
-				alertPopup.informativeText = [NSString stringWithFormat:@"Error loading source: %@", reqURL];
-				[alertPopup runModal];
-			}
-			[f.meta setErrorAndPostponeSchedule];
-		} else {
-			success = YES;
-			[f.meta setSucessfulWithResponse:response];
-			if (rss && rss.articles.count > 0) {
-				[f updateWithRSS:rss postUnreadCountChange:YES];
-				needsNotification = YES;
-			}
-		}
-		[StoreCoordinator saveContext:moc andParent:YES];
-		if (needsNotification)
-			PostNotification(kNotificationFeedUpdated, oid);
-		if (block) block(success);
-	}];
-}
-
-/**
- Download feed at url and append to persistent store in root folder.
- On error present user modal alert.
- 
- Creates new @c FeedGroup, @c Feed, @c FeedMeta and @c FeedArticle instances and saves them to the persistent store.
- Update duration is set to the default of 30 minutes.
- */
-+ (void)autoDownloadAndParseURL:(NSString*)url addAnyway:(BOOL)flag modify:(nullable void(^)(Feed *feed))block {
-	NSManagedObjectContext *moc = [StoreCoordinator createChildContext];
-	Feed *f = [Feed appendToRootWithDefaultIntervalInContext:moc];
-	f.meta.url = url;
-	if (block) block(f);
-	[StoreCoordinator saveContext:moc andParent:YES];
-	[UpdateScheduler downloadList:@[f] background:flag finally:^{
-		PostNotification(kNotificationGroupInserted, f.group.objectID);
-		[moc reset];
-		[UpdateScheduler scheduleNextFeed];
-	}];
-}
-
-/// Insert Github URL for version releases with update interval 2 days and rename @c FeedGroup item.
-+ (void)autoDownloadAndParseUpdateURL {
-	[self autoDownloadAndParseURL:versionUpdateURL addAnyway:YES modify:^(Feed *feed) {
-		feed.group.name = NSLocalizedString(@"baRSS releases", nil);
-		feed.meta.refresh = 2 * TimeUnitDays;
-	}];
-}
-
-/**
- Start download of feed xml, then continue with favicon (if newly added or 'Update all').
- 
- @param alert If @c YES display Error Popup to user.
- @param block Parameter @c success is @c YES if xml download succeeded (regardless of favicon result).
- */
-+ (void)backgroundUpdateBoth:(Feed*)feed alert:(BOOL)alert finally:(nullable void(^)(BOOL success))block {
-	BOOL recentlyAdded = (feed.articles.count == 0);
-	[self backgroundUpdateFeed:feed showErrorAlert:alert finally:^(BOOL success) {
-		if (success && (recentlyAdded || _requestsAreUrgent)) {
-			[self backgroundUpdateFavicon:feed replaceExisting:NO finally:^{
-				if (block) block(YES);
-			}];
-		} else {
-			if (block) block(success);
-		}
-	}];
-}
-
-/**
- Start download of all feeds in list. Favicons will be loaded for new feeds and for 'Update all'.
- 
- @param list Download list using @c feed.meta.url as download url. (while reusing etag and modified headers)
- @param alert If @c YES display Error Popup to user.
- @param block Called after all downloads finished.
- */
-+ (void)batchDownloadFeeds:(NSArray<Feed*>*)list showErrorAlert:(BOOL)alert finally:(nullable os_block_t)block {
-	atomic_fetch_add_explicit(&_queueSize, list.count, memory_order_relaxed);
-	PostNotification(kNotificationBackgroundUpdateInProgress, @(_queueSize));
-	dispatch_group_t group = dispatch_group_create();
-	for (Feed *f in list) {
-		dispatch_group_enter(group);
-		[self backgroundUpdateBoth:f alert:alert finally:^(BOOL success){
-			atomic_fetch_sub_explicit(&_queueSize, 1, memory_order_relaxed);
-			PostNotification(kNotificationBackgroundUpdateInProgress, @(_queueSize));
-			dispatch_group_leave(group);
-		}];
-	}
-	dispatch_group_notify(group, dispatch_get_main_queue(), ^{
-		if (block) block();
-	});
-}
-
-
-#pragma mark - Download Favicon
-
-
-/**
- Start favicon download request on existing @c Feed object.
- 
- @note Will post a @c kNotificationFeedIconUpdated notification if icon was updated.
- 
- @param overwrite If @c YES and icon is present already, @c block will return immediatelly.
- */
-+ (void)backgroundUpdateFavicon:(Feed*)feed replaceExisting:(BOOL)overwrite finally:(nullable os_block_t)block {
-	if (!overwrite && feed.icon != nil) {
-		if (block) block();
-		return; // skip existing icons if replace == NO
-	}
-	NSManagedObjectID *oid = feed.objectID;
-	NSManagedObjectContext *moc = feed.managedObjectContext;
-	NSString *faviconURL = (feed.link.length > 0 ? feed.link : feed.meta.url);
-	[self downloadFavicon:faviconURL finished:^(NSImage *img) {
-		Feed *f = [moc objectWithID:oid];
-		if (f && [f setIconImage:img]) {
-			[StoreCoordinator saveContext:moc andParent:YES];
-			PostNotification(kNotificationFeedIconUpdated, oid);
-		}
-		if (block) block();
-	}];
-}
-
-/// Download favicon located at http://.../ @c favicon.ico. Callback @c block will be called on main thread.
-+ (void)downloadFavicon:(NSString*)urlStr finished:(void(^)(NSImage * _Nullable img))block {
-	NSURL *host = [self hostURL:urlStr];
-	NSString *hostURL = host.absoluteString;
-	NSString *favURL = [host URLByAppendingPathComponent:@"favicon.ico"].absoluteString;
-	[self downloadImage:favURL finished:^(NSImage * _Nullable img) {
-		if (img) {
-			block(img); // is on main already (from downloadImage:)
-		} else {
-			[self downloadFaviconByParsingHTML:hostURL finished:block];
-		}
-	}];
-}
-
-/// Download html page and parse all icon urls. Starting a successive request on the favicon url.
-+ (void)downloadFaviconByParsingHTML:(NSString*)hostURL finished:(void(^)(NSImage * _Nullable img))block {
-	[self asyncRequest:[self newRequestURL:hostURL] block:^(NSData * _Nullable htmlData, NSError * _Nullable error, NSHTTPURLResponse *response) {
-		if (htmlData) {
-			// TODO: use session delegate to stop downloading after <head>
-			RSXMLData *xml = [[RSXMLData alloc] initWithData:htmlData url:response.URL];
-			RSHTMLMetadataParser *parser = [RSHTMLMetadataParser parserWithXMLData:xml];
-			RSHTMLMetadata *meta = [parser parseSync:&error];
-			if (error) meta = nil;
-			NSString *iconURL = [self faviconUrlForMetadata:meta];
-			if (iconURL) {
-				// if everything went well we can finally start a request on the url we found.
-				[self downloadImage:iconURL finished:block];
-				return;
-			}
-		}
-		dispatch_async(dispatch_get_main_queue(), ^{ block(nil); }); // on failure
-	}];
-}
-
-/// Extract favicon URL from parsed HTML metadata.
-+ (nullable NSString*)faviconUrlForMetadata:(RSHTMLMetadata*)meta {
-	if (meta) {
-		if (meta.faviconLink.length > 0) {
-			return meta.faviconLink;
-		}
-		else if (meta.iconLinks.count > 0) {
-			// at least any url (even if all items in list have size 0)
-			NSString *iconURL = meta.iconLinks.firstObject.link;
-			double best = DBL_MAX;
-			for (RSHTMLMetadataIconLink *icon in meta.iconLinks) {
-				CGSize size = [icon getSize];
-				CGFloat area = size.width * size.height;
-				if (area > 0) {
-					// find icon with closest matching size 32x32
-					double match = fabs(log10(area) - log10(32*32));
-					if (match < best) {
-						best = match;
-						iconURL = icon.link;
-					}
-				}
-			}
-			if (iconURL && iconURL.length > 0)
-				return iconURL;
-		}
-	}
-	return nil;
-}
-
-/// Download image in a background thread and notify once finished.
-+ (void)downloadImage:(NSString*)url finished:(void(^)(NSImage * _Nullable img))block {
-	[self asyncRequest:[self newRequestURL:url] block:^(NSData * _Nullable data, NSError * _Nullable e, NSHTTPURLResponse *r) {
-		NSImage *img = [[NSImage alloc] initWithData:data];
-		if (!img || ![img isValid])
-			img = nil;
-//		if (img.size.width > 16 || img.size.height > 16) {
-//			NSImage *smallImage = [NSImage imageWithSize:NSMakeSize(16, 16) flipped:NO drawingHandler:^BOOL(NSRect dstRect) {
-//				[img drawInRect:dstRect];
-//				return YES;
-//			}];
-//			if (img.TIFFRepresentation.length > smallImage.TIFFRepresentation.length)
-//				img = smallImage;
-//		}
-		dispatch_async(dispatch_get_main_queue(), ^{ block(img); });
-	}];
-}
-
-@end

baRSS/Helper/NSError+Ext.h

@@ -0,0 +1,27 @@
+//
+//  The MIT License (MIT)
+//  Copyright (c) 2019 Oleg Geier
+//
+//  Permission is hereby granted, free of charge, to any person obtaining a copy of
+//  this software and associated documentation files (the "Software"), to deal in
+//  the Software without restriction, including without limitation the rights to
+//  use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
+//  of the Software, and to permit persons to whom the Software is furnished to do
+//  so, subject to the following conditions:
+//
+//  The above copyright notice and this permission notice shall be included in all
+//  copies or substantial portions of the Software.
+//
+//  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+//  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+//  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+//  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+//  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+//  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+//  SOFTWARE.
+
+@import Cocoa;
+
+@interface NSError (Ext)
++ (instancetype)statusCode:(NSInteger)code reason:(nullable NSString*)reason;
+@end

baRSS/Helper/NSError+Ext.m

@@ -0,0 +1,113 @@
+//
+//  The MIT License (MIT)
+//  Copyright (c) 2019 Oleg Geier
+//
+//  Permission is hereby granted, free of charge, to any person obtaining a copy of
+//  this software and associated documentation files (the "Software"), to deal in
+//  the Software without restriction, including without limitation the rights to
+//  use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
+//  of the Software, and to permit persons to whom the Software is furnished to do
+//  so, subject to the following conditions:
+//
+//  The above copyright notice and this permission notice shall be included in all
+//  copies or substantial portions of the Software.
+//
+//  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+//  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+//  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+//  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+//  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+//  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+//  SOFTWARE.
+
+#import "NSError+Ext.h"
+
+@implementation NSError (Ext)
+
+static const char* CodeDescription(NSInteger code) {
+	switch (code) {
+		/* --- Informational --- */
+		case 100: return "Continue";
+		case 101: return "Switching Protocols";
+		case 102: return "Processing";
+		case 103: return "Early Hints";
+		/* --- Success --- */
+		case 200: return "OK";
+		case 201: return "Created";
+		case 202: return "Accepted";
+		case 203: return "Non-Authoritative Information";
+		case 204: return "No Content";
+		case 205: return "Reset Content";
+		case 206: return "Partial Content";
+		case 207: return "Multi-Status";
+		case 208: return "Already Reported";
+		case 226: return "IM Used";
+		/* --- Redirection --- */
+		case 300: return "Multiple Choices";
+		case 301: return "Moved Permanently";
+		case 302: return "Found";
+		case 303: return "See Other";
+		case 304: return "Not Modified";
+		case 305: return "Use Proxy";
+		case 306: return "Switch Proxy";
+		case 307: return "Temporary Redirect";
+		case 308: return "Permanent Redirect";
+		/* --- Client error --- */
+		case 400: return "Bad Request";
+		case 401: return "Unauthorized";
+		case 402: return "Payment Required";
+		case 403: return "Forbidden";
+		case 404: return "Not Found";
+		case 405: return "Method Not Allowed";
+		case 406: return "Not Acceptable";
+		case 407: return "Proxy Authentication Required";
+		case 408: return "Request Timeout";
+		case 409: return "Conflict";
+		case 410: return "Gone";
+		case 411: return "Length Required";
+		case 412: return "Precondition Failed";
+		case 413: return "Payload Too Large";
+		case 414: return "URI Too Long";
+		case 415: return "Unsupported Media Type";
+		case 416: return "Range Not Satisfiable";
+		case 417: return "Expectation Failed";
+		case 418: return "I'm a teapot";
+		case 421: return "Misdirected Request";
+		case 422: return "Unprocessable Entity";
+		case 423: return "Locked";
+		case 424: return "Failed Dependency";
+		case 425: return "Too Early";
+		case 426: return "Upgrade Required";
+		case 428: return "Precondition Required";
+		case 429: return "Too Many Requests";
+		case 431: return "Request Header Fields Too Large";
+		case 451: return "Unavailable For Legal Reasons";
+		/* --- Server error --- */
+		case 500: return "Internal Server Error";
+		case 501: return "Not Implemented";
+		case 502: return "Bad Gateway";
+		case 503: return "Service Unavailable";
+		case 504: return "Gateway Timeout";
+		case 505: return "HTTP Version Not Supported";
+		case 506: return "Variant Also Negotiates";
+		case 507: return "Insufficient Storage";
+		case 508: return "Loop Detected";
+		case 510: return "Not Extended";
+		case 511: return "Network Authentication Required";
+	}
+	return "Unknown";
+}
+
+/// Generate @c NSError from HTTP status code. E.g., @c code @c = @c 404 will return "404 Not Found".
++ (instancetype)statusCode:(NSInteger)code reason:(nullable NSString*)reason {
+	NSMutableDictionary *info = [NSMutableDictionary dictionaryWithCapacity:2];
+	info[NSLocalizedDescriptionKey] = [NSString stringWithFormat:@"%ld %s.", code, CodeDescription(code)];
+	if (reason) info[NSLocalizedRecoverySuggestionErrorKey] = reason;
+	
+	NSInteger errCode = NSURLErrorUnknown;
+	if (code < 500) { if (code >= 400) errCode = NSURLErrorResourceUnavailable; }
+	else if (code < 600) errCode = NSURLErrorBadServerResponse;
+	return [NSError errorWithDomain:NSURLErrorDomain code:errCode userInfo:info];
+}
+
+@end

baRSS/Helper/NSURL+Ext.h

@@ -0,0 +1,31 @@
+//
+//  The MIT License (MIT)
+//  Copyright (c) 2019 Oleg Geier
+//
+//  Permission is hereby granted, free of charge, to any person obtaining a copy of
+//  this software and associated documentation files (the "Software"), to deal in
+//  the Software without restriction, including without limitation the rights to
+//  use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
+//  of the Software, and to permit persons to whom the Software is furnished to do
+//  so, subject to the following conditions:
+//
+//  The above copyright notice and this permission notice shall be included in all
+//  copies or substantial portions of the Software.
+//
+//  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+//  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+//  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+//  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+//  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+//  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+//  SOFTWARE.
+
+@import Cocoa;
+
+@interface NSURL (Ext)
++ (NSURL*)faviconsCacheURL;
+- (BOOL)existsAndIsDir:(BOOL)dir;
+- (BOOL)mkdir;
+- (void)remove;
+- (void)moveTo:(NSURL*)destination;
+@end

baRSS/Helper/NSURL+Ext.m

@@ -0,0 +1,76 @@
+//
+//  The MIT License (MIT)
+//  Copyright (c) 2019 Oleg Geier
+//
+//  Permission is hereby granted, free of charge, to any person obtaining a copy of
+//  this software and associated documentation files (the "Software"), to deal in
+//  the Software without restriction, including without limitation the rights to
+//  use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
+//  of the Software, and to permit persons to whom the Software is furnished to do
+//  so, subject to the following conditions:
+//
+//  The above copyright notice and this permission notice shall be included in all
+//  copies or substantial portions of the Software.
+//
+//  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+//  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+//  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+//  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+//  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+//  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+//  SOFTWARE.
+
+#import "NSURL+Ext.h"
+#import "UserPrefs.h" // appName in +faviconsCacheURL
+
+@implementation NSURL (Ext)
+
+/// @return Directory URL pointing to "Application Support/baRSS/favicons". Does @b not create directory!
++ (NSURL*)faviconsCacheURL {
+	static NSURL *path = nil;
+	static dispatch_once_t onceToken;
+	dispatch_once(&onceToken, ^{
+		path = [[NSFileManager defaultManager] URLForDirectory:NSApplicationSupportDirectory inDomain:NSUserDomainMask appropriateForURL:nil create:YES error:nil];
+		path = [path URLByAppendingPathComponent:[UserPrefs appName] isDirectory:YES];
+		path = [path URLByAppendingPathComponent:@"favicons" isDirectory:YES];
+	});
+	return path;
+}
+
+/// @return @c YES if and only if item exists at URL and item matches @c dir flag
+- (BOOL)existsAndIsDir:(BOOL)dir {
+	BOOL d;
+	return self.path && [[NSFileManager defaultManager] fileExistsAtPath:self.path isDirectory:&d] && d == dir;
+}
+
+/**
+ Create directory at URL. If directory exists, this method does nothing.
+ @return @c YES if dir created successfully. @c NO if dir already exists or an error occured.
+ */
+- (BOOL)mkdir {
+	if ([self existsAndIsDir:YES]) return NO;
+	NSError *err;
+	BOOL b = [[NSFileManager defaultManager] createDirectoryAtURL:self withIntermediateDirectories:YES attributes:nil error:&err];
+	if (err) [NSApp presentError:err];
+	return b;
+}
+
+/// Delete file or folder at URL. If item does not exist, this method does nothing.
+- (void)remove {
+	BOOL success = [[NSFileManager defaultManager] removeItemAtURL:self error:nil];
+#ifdef DEBUG
+	if (success) printf("DEL %s\n", self.absoluteString.UTF8String);
+#endif
+}
+
+/// Move file to destination (by replacing any existing file)
+- (void)moveTo:(NSURL*)destination {
+	[[NSFileManager defaultManager] removeItemAtURL:destination error:nil];
+	[[NSFileManager defaultManager] moveItemAtURL:self toURL:destination error:nil];
+#ifdef DEBUG
+	printf("MOVE %s\n", self.absoluteString.UTF8String);
+	printf(" ↳ %s\n", destination.absoluteString.UTF8String);
+#endif
+}
+
+@end

baRSS/Helper/NSURLRequest+Ext.h

@@ -0,0 +1,29 @@
+//
+//  The MIT License (MIT)
+//  Copyright (c) 2019 Oleg Geier
+//
+//  Permission is hereby granted, free of charge, to any person obtaining a copy of
+//  this software and associated documentation files (the "Software"), to deal in
+//  the Software without restriction, including without limitation the rights to
+//  use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
+//  of the Software, and to permit persons to whom the Software is furnished to do
+//  so, subject to the following conditions:
+//
+//  The above copyright notice and this permission notice shall be included in all
+//  copies or substantial portions of the Software.
+//
+//  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+//  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+//  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+//  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+//  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+//  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+//  SOFTWARE.
+
+@import Cocoa;
+
+@interface NSURLRequest (Ext)
++ (instancetype)withURL:(NSString*)urlStr;
+- (NSURLSessionDataTask*)dataTask:(nonnull void(^)(NSData * _Nullable data, NSError * _Nullable error, NSHTTPURLResponse *response))block;
+- (NSURLSessionDownloadTask*)downloadTask:(void(^)(NSURL * _Nullable path, NSError * _Nullable error))block;
+@end

baRSS/Helper/NSURLRequest+Ext.m

@@ -0,0 +1,97 @@
+//
+//  The MIT License (MIT)
+//  Copyright (c) 2019 Oleg Geier
+//
+//  Permission is hereby granted, free of charge, to any person obtaining a copy of
+//  this software and associated documentation files (the "Software"), to deal in
+//  the Software without restriction, including without limitation the rights to
+//  use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
+//  of the Software, and to permit persons to whom the Software is furnished to do
+//  so, subject to the following conditions:
+//
+//  The above copyright notice and this permission notice shall be included in all
+//  copies or substantial portions of the Software.
+//
+//  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+//  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+//  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+//  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+//  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+//  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+//  SOFTWARE.
+
+#import "NSURLRequest+Ext.h"
+#import "NSString+Ext.h"
+#import "NSError+Ext.h"
+
+/// @return Shared URL session with caches disabled, enabled gzip encoding and custom user agent.
+static NSURLSession* NonCachingURLSession(void) {
+	static NSURLSession *session = nil;
+	static dispatch_once_t onceToken;
+	dispatch_once(&onceToken, ^{
+		NSURLSessionConfiguration *conf = [NSURLSessionConfiguration defaultSessionConfiguration];
+		conf.HTTPCookieAcceptPolicy = NSHTTPCookieAcceptPolicyNever;
+		conf.HTTPShouldSetCookies = NO;
+		conf.HTTPCookieStorage = nil; // disables '~/Library/Cookies/'
+		conf.requestCachePolicy = NSURLRequestReloadIgnoringLocalCacheData;
+		conf.URLCache = nil; // disables '~/Library/Caches/de.relikd.baRSS/'
+		conf.HTTPAdditionalHeaders = @{ @"User-Agent": @"baRSS (macOS)",
+										@"Accept-Encoding": @"gzip" };
+		session = [NSURLSession sessionWithConfiguration:conf];
+	});
+	return session;
+}
+
+
+@implementation NSURLRequest (Ext)
+
+/// @return New request from URL. Ensures that at least @c http scheme is set.
++ (instancetype)withURL:(NSString*)urlStr {
+	NSURL *url = [NSURL URLWithString:urlStr];
+	if (!url.scheme)
+		url = [NSURL URLWithString:[NSString stringWithFormat:@"http://%@", urlStr]]; // will redirect to https
+	return [self requestWithURL:url];
+}
+
+/// Perform request with non caching @c NSURLSession . If HTTP status code is @c 304 then @c data @c = @c nil.
+- (NSURLSessionDataTask*)dataTask:(nonnull void(^)(NSData * _Nullable data, NSError * _Nullable error, NSHTTPURLResponse *response))block {
+	NSURLSessionDataTask *task = [NonCachingURLSession() dataTaskWithRequest:self completionHandler:^(NSData * _Nullable data, NSURLResponse * _Nullable response, NSError * _Nullable error) {
+		NSHTTPURLResponse* httpResponse = (NSHTTPURLResponse*)response;
+		NSInteger status = [httpResponse statusCode];
+#ifdef DEBUG
+		/*if (status != 304)*/ printf("GET %ld %s\n", status, self.URL.absoluteString.UTF8String);
+#endif
+		if (error || status == 304) {
+			data = nil; // if status == 304, data & error nil
+		} else if (status >= 400 && status < 600) { // catch Client & Server errors
+			error = [NSError statusCode:status reason:(status >= 500 ? [NSString plainTextFromHTMLData:data] : nil)];
+			data = nil;
+		}
+		block(data, error, httpResponse);
+	}];
+	[task resume];
+	return task;
+}
+
+/// Prepare a download task and immediatelly perform request with non caching URL session.
+- (NSURLSessionDownloadTask*)downloadTask:(void(^)(NSURL * _Nullable path, NSError * _Nullable error))block {
+	NSURLSessionDownloadTask *task = [NonCachingURLSession() downloadTaskWithRequest:self completionHandler:^(NSURL * _Nullable location, NSURLResponse * _Nullable response, NSError * _Nullable error) {
+		block(location, error);
+	}];
+	[task resume];
+	return task;
+}
+
+/*
+ Developer Tip, error log:
+ 
+ Task <..> HTTP load failed (error code: -1003 [12:8])
+ Task <..> finished with error - code: -1003  ---  NSURLErrorCannotFindHost
+ ==> NSURLErrorCannotFindHost in #import <Foundation/NSURLError.h>
+ 
+ TIC TCP Conn Failed [21:0x1d417fb00]: 1:65 Err(65)  ---  EHOSTUNREACH, No route to host
+ TIC Read Status [9:0x0]: 1:57  ---  ENOTCONN, Socket is not connected
+ ==> EHOSTUNREACH in #import <sys/errno.h>
+ */
+
+@end

baRSS/Info.plist

@@ -70,7 +70,7 @@
 		</dict>
 	</array>
 	<key>CFBundleVersion</key>
-	<string>11519</string>
+	<string>13197</string>
 	<key>LSApplicationCategoryType</key>
 	<string>public.app-category.news</string>
 	<key>LSMinimumSystemVersion</key>

baRSS/Preferences/Feeds Tab/ModalFeedEdit.m

@@ -20,20 +20,25 @@
 //  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 //  SOFTWARE.
 
+@import RSXML;
 #import "ModalFeedEdit.h"
-#import "WebFeed.h"
+#import "ModalFeedEditView.h"
-#import "StoreCoordinator.h"
+#import "RefreshStatisticsView.h"
+#import "Constants.h"
+#import "FeedDownload.h"
+#import "FaviconDownload.h"
 #import "Feed+Ext.h"
 #import "FeedMeta+Ext.h"
 #import "FeedGroup+Ext.h"
-#import "ModalFeedEditView.h"
-#import "RefreshStatisticsView.h"
-#import "NSDate+Ext.h"
 #import "NSView+Ext.h"
+#import "NSDate+Ext.h"
+#import "NSURL+Ext.h"
 
-
+// ################################################################
-#pragma mark - ModalEditDialog -
+// #
-
+// #  MARK: - ModalEditDialog -
+// #
+// ################################################################
 
 @interface ModalEditDialog() <NSWindowDelegate>
 @property (strong) FeedGroup *feedGroup;
@@ -62,21 +67,20 @@
 }
 @end
 
+// ################################################################
+// #
+// #  MARK: - ModalFeedEdit -
+// #
+// ################################################################
 
-#pragma mark - ModalFeedEdit -
+@interface ModalFeedEdit() <FeedDownloadDelegate, RefreshIntervalButtonDelegate, FaviconDownloadDelegate>
-
-
-@interface ModalFeedEdit() <RefreshIntervalButtonDelegate>
 @property (strong) IBOutlet ModalFeedEditView *view; // override
 
-@property (strong) RefreshStatisticsView *statisticsView;
-
 @property (copy) NSString *previousURL; // check if changed and avoid multiple download
-@property (copy) NSString *faviconURL;
+@property (strong) NSURL *faviconFile;
-@property (strong) NSError *feedError; // download error or xml parser error
+@property (strong) FeedDownload *memFeed;
-@property (strong) RSParsedFeed *feedResult; // parsed result
+@property (weak) FaviconDownload *memIcon;
-@property (strong) NSHTTPURLResponse *httpResponse;
+@property (strong) RefreshStatisticsView *statisticsView;
-@property (assign) BOOL didDownloadFeed; // check if feed articles need update
 @end
 
 @implementation ModalFeedEdit
@@ -91,12 +95,11 @@
 	[self populateTextFields:self.feedGroup];
 }
 
-/**
+/// Pre-fill UI control field values with @c FeedGroup properties.
- Pre-fill UI control field values with @c FeedGroup properties.
- */
 - (void)populateTextFields:(FeedGroup*)fg {
 	if (!fg || [fg hasChanges]) return; // hasChanges is true only if newly created
-	self.view.name.objectValue = fg.name;
+	self.view.name.objectValue = fg.name; // user given feed title
+	self.view.name.placeholderString = fg.feed.title; // actual feed title
 	self.view.url.objectValue = fg.feed.meta.url;
 	self.previousURL = self.view.url.stringValue;
 	self.view.favicon.image = [fg.feed iconImage16];
@@ -104,6 +107,10 @@
 	[self statsForCoreDataObject];
 }
 
+- (void)dealloc {
+	[self.faviconFile remove]; // Delete temporary favicon (if still exists)
+}
+
 #pragma mark - Edit Feed Data
 
 /**
@@ -111,63 +118,42 @@
  Set @c scheduled to a new date if refresh interval was changed.
  */
 - (void)applyChangesToCoreDataObject {
-	Feed *feed = self.feedGroup.feed;
+	Feed *f = self.feedGroup.feed;
+	Interval intv = [NSDate intervalForPopup:self.view.refreshUnit andField:self.view.refreshNum];
 	[self.feedGroup setNameIfChanged:self.view.name.stringValue];
-	FeedMeta *meta = feed.meta;
+	[f.meta setRefreshIfChanged:intv];
-	[meta setUrlIfChanged:self.previousURL];
+	if (self.memFeed) {
-	[meta setRefreshAndSchedule:[NSDate intervalForPopup:self.view.refreshUnit andField:self.view.refreshNum]];
+		[self.memFeed copyValuesTo:f ignoreError:YES];
-	// updateTimer will be scheduled once preferences is closed
+		[f setNewIcon:self.faviconFile]; // only if downloaded anything (nil deletes icon!)
-	if (self.didDownloadFeed) {
+		self.faviconFile = nil;
-		[meta setSucessfulWithResponse:self.httpResponse];
-		[feed updateWithRSS:self.feedResult postUnreadCountChange:YES];
-		[feed setIconImage:self.view.favicon.image];
 	}
 }
 
+/// Cancel any running download task and free volatile variables
+- (void)cancelDownloads {
+	[self.memFeed cancel];  self.memFeed = nil;
+	[self.memIcon cancel];  self.memIcon = nil;
+	[self.faviconFile remove];  self.faviconFile = nil;
+}
+
 /**
- Prepare UI (nullify @c result, @c error and start @c ProgressIndicator).
+ Prepare UI (nullify results and start @c ProgressIndicator ).
- Also disable 'Done' button during download and re-enable after all downloads are finished.
+ Also disable 'Done' button during download and re-enable after download is finished.
  */
-- (void)preDownload {
+- (void)downloadRSS {
+	[self cancelDownloads];
 	[self.modalSheet setDoneEnabled:NO]; // prevent user from closing the dialog during download
 	[self.view.spinnerURL startAnimation:nil];
 	[self.view.spinnerName startAnimation:nil];
 	self.view.favicon.image = nil;
 	self.view.warningButton.hidden = YES;
-	self.didDownloadFeed = NO;
+	// User didn't change title since last fetch. Will be pre-filled with new title after download
-	// Assuming the user has not changed title since the last fetch.
+	if ([self.view.name.stringValue isEqualToString:self.view.name.placeholderString]) {
-	// Reset to "" because after download it will be pre-filled with new feed title
-	if ([self.view.name.stringValue isEqualToString:self.feedResult.title]) {
 		self.view.name.stringValue = @"";
+		self.view.name.placeholderString = NSLocalizedString(@"Loading …", nil);
 	}
-	self.feedError = nil;
-	self.feedResult = nil;
-	self.httpResponse = nil;
-	self.faviconURL = nil;
 	self.previousURL = self.view.url.stringValue;
-}
+	self.memFeed = [[FeedDownload withURL:self.previousURL] startWithDelegate:self];
-
-/**
- All properties will be parsed and stored in class variables.
- This should avoid unnecessary core data operations if user decides to cancel the edit.
- The save operation will only be executed if user clicks on the 'OK' button.
- */
-- (void)downloadRSS {
-	if (self.modalSheet.didCloseAndCancel)
-		return;
-	[self preDownload];
-	[WebFeed newFeed:self.previousURL askUser:^NSString *(RSHTMLMetadata *meta) {
-		self.faviconURL = [WebFeed faviconUrlForMetadata:meta]; // we can re-use favicon url if we find one
-		return [self letUserChooseXmlUrlFromList:meta.feedLinks];
-	} block:^(RSParsedFeed *result, NSError *error, NSHTTPURLResponse* response) {
-		if (self.modalSheet.didCloseAndCancel)
-			return;
-		self.didDownloadFeed = YES;
-		self.feedResult = result;
-		self.feedError = error;
-		self.httpResponse = response;
-		[self postDownload:response.URL.absoluteString];
-	}];
 }
 
 /**
@@ -176,12 +162,7 @@
  
  @return Either URL string or @c nil if user canceled the selection.
  */
-- (NSString*)letUserChooseXmlUrlFromList:(NSArray<RSHTMLMetadataFeedLink*> *)list {
+- (NSString*)feedDownload:(FeedDownload*)sender selectFeedFromList:(NSArray<RSHTMLMetadataFeedLink*>*)list {
-	if (list.count == 1) { // nothing to choose
-		// Feeds like https://news.ycombinator.com/ return 503 if URLs are requested too rapidly
-		//CFRunLoopRunInMode(kCFRunLoopDefaultMode, 1.0, false); // Non-blocking sleep (1s)
-		return list.firstObject.link;
-	}
 	NSMenu *menu = [[NSMenu alloc] initWithTitle:NSLocalizedString(@"Choose feed menu", nil)];
 	menu.autoenablesItems = NO;
 	for (RSHTMLMetadataFeedLink *fl in list) {
@@ -196,62 +177,53 @@
 	return nil; // user selection canceled
 }
 
-/**
+/// If URL was redirected, replace original text field value with new one. (e.g., https redirect)
- Update UI TextFields with downloaded values.
+- (void)feedDownload:(FeedDownload*)sender urlRedirected:(NSString*)newURL {
- Title will be updated if TextField is empty. URL on redirect.
+	if (!sender.error) {
- Finally begin favicon download and return control to user (enable 'Done' button).
- */
-- (void)postDownload:(NSString*)responseURL {
-	if (self.modalSheet.didCloseAndCancel)
-		return;
-	
-	BOOL hasError = (self.feedError != nil);
-	// 1. Stop spinner animation for name field. (keep spinner for URL running until favicon downloaded)
-	[self.view.spinnerName stopAnimation:nil];
-	// 2. If URL was redirected, replace original text field value with new one. (e.g., https redirect)
-	if (responseURL.length > 0 && ![responseURL isEqualToString:self.previousURL]) {
-		if (!hasError) {
 		// If the url has changed and there is an error:
 		// This probably means the feed URL was resolved, but the successive download returned 5xx error.
 		// Presumably to prevent site crawlers accessing many pages in quick succession. (delay of 1s does help)
 		// By not setting previousURL, a second hit on the 'Done' button will retry the resolved URL again.
-			self.previousURL = responseURL;
+		self.previousURL = newURL;
 	}
-		self.view.url.stringValue = responseURL;
+	self.view.url.stringValue = newURL;
 }
-	// 3. Copy parsed feed title to text field. (only if user hasn't set anything else yet)
+
-	NSString *parsedTitle = self.feedResult.title;
+/// Update UI TextFields with downloaded values. Title updated if TextField is empty, URL if redirect.
-	if (parsedTitle.length > 0 && [self.view.name.stringValue isEqualToString:@""]) {
+- (void)feedDownloadDidFinish:(FeedDownload*)sender {
-		self.view.name.stringValue = parsedTitle; // no damage to replace an empty string
+	// Stop spinner for name field but keep running for URL until favicon downloaded
+	[self.view.spinnerName stopAnimation:nil];
+	NSString *newTitle = sender.xmlfeed.title;
+	self.view.name.placeholderString = newTitle;
+	if (newTitle.length > 0 && self.view.name.stringValue.length == 0) {
+		self.view.name.stringValue = newTitle; // only if default title wasn't changed
 	}
 	// TODO: user preference to automatically select refresh interval (selection: None,min,max,avg,median)
-	[self statsForDownloadObject];
+	[self statsForDownloadObject:sender.xmlfeed.articles];
-	// 4. Continue with favicon download (or finish with error)
+	BOOL hasError = (sender.error != nil);
 	self.view.favicon.hidden = hasError;
 	self.view.warningButton.hidden = !hasError;
-	if (hasError) {
+	// Start favicon download
-		[self finishDownloadWithFavicon];
+	if (hasError)
-	} else {
+		[self downloadComplete];
-		if (!self.faviconURL)
+	else
-			self.faviconURL = self.feedResult.link;
+		self.memIcon = [[sender faviconDownload] startWithDelegate:self];
-		if (self.faviconURL.length == 0)
-			self.faviconURL = responseURL;
-		[WebFeed downloadFavicon:self.faviconURL finished:^(NSImage * _Nullable img) {
-			if (self.modalSheet.didCloseAndCancel)
-				return;
-			self.view.favicon.image = img;
-			[self finishDownloadWithFavicon];
-		}];
-	}
 }
 
 /**
  The last step of the download process.
- Stop spinning animation set favivon image preview (right of url bar) and re-enable 'Done' button.
+ Stop spinning animation, set favivon image (right of url bar), and re-enable 'Done' button.
  */
-- (void)finishDownloadWithFavicon {
+- (void)faviconDownload:(FaviconDownload*)sender didFinish:(nullable NSURL*)path {
-	if (self.modalSheet.didCloseAndCancel)
+	// Create image from favicon temporary file location or default icon if no favicon exists.
-		return;
+	NSImage *img = path ? [[NSImage alloc] initByReferencingURL:path] : [NSImage imageNamed:RSSImageDefaultRSSIcon];
+	self.view.favicon.image = img;
+	self.faviconFile = path;
+	[self downloadComplete];
+}
+
+/// Called regardless of favicon download.
+- (void)downloadComplete {
 	[self.view.spinnerURL stopAnimation:nil];
 	[self.modalSheet setDoneEnabled:YES];
 }
@@ -259,15 +231,15 @@
 #pragma mark - Feed Statistics
 
 /// Perform statistics on newly downloaded feed item
-- (void)statsForDownloadObject {
+- (void)statsForDownloadObject:(NSArray<RSParsedArticle*>*)articles {
-	NSMutableArray<NSDate*> *arr = [NSMutableArray arrayWithCapacity:self.feedResult.articles.count];
+	NSMutableArray<NSDate*> *arr = [NSMutableArray arrayWithCapacity:articles.count];
-	for (RSParsedArticle *a in self.feedResult.articles) {
+	for (RSParsedArticle *a in articles) {
 		NSDate *d = a.datePublished;
 		if (!d) d = a.dateModified;
 		if (!d) continue;
 		[arr addObject:d];
 	}
-	[self appendViewWithFeedStatistics:arr count:self.feedResult.articles.count];
+	[self appendViewWithFeedStatistics:arr count:articles.count];
 }
 
 /// Perform statistics on stored core data object
@@ -301,8 +273,10 @@
 
 
 /// Window delegate will be only called on button 'Done'.
-- (BOOL)windowShouldClose:(NSWindow *)sender {
+- (BOOL)windowShouldClose:(ModalSheet*)sender {
-	if (![self.previousURL isEqualToString:self.view.url.stringValue]) {
+	if (sender.didTapCancel) {
+		[self cancelDownloads];
+	} else if (![self.previousURL isEqualToString:self.view.url.stringValue]) { // 'Done' button
 		[[NSNotificationCenter defaultCenter] postNotificationName:NSControlTextDidEndEditingNotification object:self.view.url];
 		return NO;
 	}
@@ -311,7 +285,7 @@
 
 /// Whenever the user finished entering the url (return key or focus change) perform a download request.
 - (void)controlTextDidEndEditing:(NSNotification*)obj {
-	if (obj.object == self.view.url) {
+	if (obj.object == self.view.url && !self.modalSheet.didTapCancel) {
 		if (![self.previousURL isEqualToString:self.view.url.stringValue]) {
 			[self downloadRSS];
 		}
@@ -320,15 +294,18 @@
 
 /// Warning button next to url text field. Will be visible if an error occurs during download.
 - (void)didClickWarningButton:(NSButton*)sender {
-	if (!self.feedError)
+	NSError *err = self.memFeed.error;
-		return;
+	if (!err) return;
 	
 	// show reload button if server is temporarily offline (any 5xx server error)
-	BOOL serverError = (self.feedError.domain == NSURLErrorDomain && self.feedError.code == NSURLErrorBadServerResponse);
+	BOOL serverError = (err.code == NSURLErrorBadServerResponse && err.domain == NSURLErrorDomain);
 	self.view.warningReload.hidden = !serverError;
 	
 	// set error description as text
-	self.view.warningText.objectValue = self.feedError.localizedDescription;
+	if (serverError)
+		self.view.warningText.stringValue = [NSString stringWithFormat:@"%@\n––––\n%@", err.localizedDescription, err.localizedRecoverySuggestion];
+	else
+		self.view.warningText.objectValue = err.localizedDescription;
 	NSSize newSize = self.view.warningText.fittingSize; // width is limited by the textfield's preferred width
 	newSize.width += 2 * self.view.warningText.frame.origin.x; // the padding
 	newSize.height += 2 * self.view.warningText.frame.origin.y;
@@ -345,9 +322,11 @@
 
 @end
 
-
+// ################################################################
-#pragma mark - ModalGroupEdit -
+// #
-
+// #  MARK: - ModalGroupEdit -
+// #
+// ################################################################
 
 @implementation ModalGroupEdit
 /// Init view and set group name if edeting an already existing object.

baRSS/Preferences/Feeds Tab/SettingsFeeds+DragDrop.m

@@ -144,9 +144,8 @@ const NSPasteboardType dragReorder = @"de.relikd.baRSS.drag-reorder";
 		return;
 	}
 	// Get list of feeds, and root level selection
-	NSUInteger count = moc.insertedObjects.count;
+	NSMutableArray<NSIndexPath*> *selection = [NSMutableArray array];
-	NSMutableArray<NSIndexPath*> *selection = [NSMutableArray arrayWithCapacity:count];
+	NSMutableArray<Feed*> *feedsList = [NSMutableArray array];
-	NSMutableArray<Feed*> *feedsList = [NSMutableArray arrayWithCapacity:count];
 	for (__kindof NSManagedObject *obj in moc.insertedObjects) {
 		if ([obj isKindOfClass:[Feed class]]) {
 			[feedsList addObject:obj]; // list of feeds that need download
@@ -161,8 +160,10 @@ const NSPasteboardType dragReorder = @"de.relikd.baRSS.drag-reorder";
 	if (selection.count > 0)
 		[self.dataStore setSelectionIndexPaths:[selection sortedArrayUsingSelector:@selector(compare:)]];
 	
-	[UpdateScheduler downloadList:feedsList background:NO finally:^{
+	[UpdateScheduler downloadList:feedsList userInitiated:YES finally:^{
 		[self endCoreDataChangeUndoEmpty:NO forceUndo:NO];
+		for (Feed *f in feedsList)
+			[moc refreshObject:f.group mergeChanges:NO]; // fixes blank icon if imported with no inet conn
 		[UpdateScheduler scheduleNextFeed];
 	}];
 }
@@ -243,7 +244,7 @@ const NSPasteboardType dragReorder = @"de.relikd.baRSS.drag-reorder";
 	return result;
 }
 
-NS_INLINE BOOL IndexPathIsChildOfParent(NSIndexPath *child, NSIndexPath *parent) {
+static inline BOOL IndexPathIsChildOfParent(NSIndexPath *child, NSIndexPath *parent) {
 	while (child.length > parent.length)
 		child = [child indexPathByRemovingLastIndex];
 	return [child isEqualTo:parent];

baRSS/Preferences/Feeds Tab/SettingsFeeds.m

@@ -47,9 +47,9 @@
 - (void)viewDidLoad {
     [super viewDidLoad];
 	// Register for notifications
-	RegisterNotification(kNotificationFeedUpdated, @selector(feedUpdated:), self);
+	RegisterNotification(kNotificationArticlesUpdated, @selector(feedUpdated:), self);
 	RegisterNotification(kNotificationFeedIconUpdated, @selector(feedUpdated:), self);
-	RegisterNotification(kNotificationGroupInserted, @selector(groupInserted:), self);
+	RegisterNotification(kNotificationFeedGroupInserted, @selector(feedGroupInserted:), self);
 	// Status bar
 	RegisterNotification(kNotificationScheduleTimerChanged, @selector(updateStatusInfo), self);
 	RegisterNotification(kNotificationNetworkStatusChanged, @selector(updateStatusInfo), self);
@@ -58,6 +58,8 @@
 
 - (void)dealloc {
 	[[NSNotificationCenter defaultCenter] removeObserver:self];
+	NSUInteger c = [StoreCoordinator cleanupFavicons];
+	if (c > 0) NSLog(@"Removed %lu unreferenced favicons", c);
 }
 
 /// Initialize status info timer
@@ -97,10 +99,8 @@
 	self.dataStore.sortDescriptors = [NSArray arrayWithObject:[NSSortDescriptor sortDescriptorWithKey:@"sortIndex" ascending:YES]];
 	
 	NSError *error;
-	BOOL ok = [self.dataStore fetchWithRequest:nil merge:NO error:&error];
+	[self.dataStore fetchWithRequest:nil merge:NO error:&error];
-	if (!ok || error) {
+	if (error) [NSApp presentError:error];
-		[[NSApplication sharedApplication] presentError:error];
-	}
 }
 
 /**
@@ -160,7 +160,7 @@
 }
 
 /// Callback method fired when feed is inserted via a 'feed://' url
-- (void)groupInserted:(NSNotification*)notify {
+- (void)feedGroupInserted:(NSNotification*)notify {
 	[self.dataStore fetch:self];
 }
 
@@ -312,7 +312,7 @@
 		}
 		if ([self endCoreDataChangeUndoEmpty:YES forceUndo:(returnCode != NSModalResponseOK)]) {
 			if (!flag) [UpdateScheduler scheduleNextFeed]; // only for feed edit
-			[self.dataStore rearrangeObjects]; // update display, edited title or icon
+			[self.dataStore.managedObjectContext refreshObject:fg mergeChanges:NO]; // update title & icon
 		}
 	}];
 }

baRSS/Preferences/Feeds Tab/SettingsFeedsView.m

@@ -203,7 +203,7 @@ NSUserInterfaceItemIdentifier const CustomCellName = @"NameColumnCell";
 }
 
 - (void)setObjectValue:(FeedGroup*)fg {
-	self.textField.objectValue = fg.name;
+	self.textField.objectValue = fg.anyName;
 	self.imageView.image = fg.iconImage16;
 }
 

baRSS/Preferences/Helper/ModalSheet.h

@@ -23,7 +23,7 @@
 @import Cocoa;
 
 @interface ModalSheet : NSPanel
-@property (readonly) BOOL didCloseAndCancel;
+@property (readonly) BOOL didTapCancel;
 
 - (instancetype)initWithContentRect:(NSRect)contentRect styleMask:(NSWindowStyleMask)style backing:(NSBackingStoreType)backingStoreType defer:(BOOL)flag NS_UNAVAILABLE;
 - (instancetype)initWithView:(NSView*)content NS_DESIGNATED_INITIALIZER;

baRSS/Preferences/Helper/ModalSheet.m

@@ -81,14 +81,14 @@
 
 /**
  Called after user has clicked the 'Done' (Return) or 'Cancel' (Esc) button.
- In the later case set @c .didCloseAndCancel @c = @c YES
+ In the later case set @c .didTapCancel @c = @c YES
  */
 - (void)didTapButton:(NSButton*)sender {
 	BOOL successful = (sender.tag == 42); // 'Done' button
-	if (successful && self.respondToShouldClose && ![self.delegate windowShouldClose:self]) {
+	_didTapCancel = !successful;
+	if (self.respondToShouldClose && ![self.delegate windowShouldClose:self]) {
 		return;
 	}
-	_didCloseAndCancel = !successful;
 	// Save modal view width for next time
 	CGFloat w = NSWidth(self.contentView.frame) - 2 * PAD_WIN;
 	[[NSUserDefaults standardUserDefaults] setInteger:(NSInteger)w forKey:@"modalSheetWidth"];

baRSS/Status Bar Menu/BarMenu.m

@@ -28,6 +28,7 @@
 #import "MapUnreadTotal.h"
 #import "StoreCoordinator.h"
 #import "Feed+Ext.h"
+#import "FeedGroup+Ext.h"
 #import "FeedArticle+Ext.h"
 
 
@@ -45,7 +46,7 @@
 	// TODO: move unread counts to status item and keep in sync when changing feeds in preferences
 	self.unreadMap = [[MapUnreadTotal alloc] initWithCoreData: [StoreCoordinator countAggregatedUnread]];
 	// Register for notifications
-	RegisterNotification(kNotificationFeedUpdated, @selector(feedUpdated:), self);
+	RegisterNotification(kNotificationArticlesUpdated, @selector(articlesUpdated:), self);
 	RegisterNotification(kNotificationFeedIconUpdated, @selector(feedIconUpdated:), self);
 	return self;
 }
@@ -129,21 +130,15 @@
 - (void)updateFeedMenuItem:(NSManagedObjectID*)oid withBlock:(void(^)(Feed *feed, NSMenuItem *item))block {
 	NSManagedObjectContext *moc = [StoreCoordinator createChildContext];
 	Feed *feed = [moc objectWithID:oid];
-	if (![feed isKindOfClass:[Feed class]]) {
+	if ([feed isKindOfClass:[Feed class]]) {
-		[moc reset];
-		return;
-	}
 		NSMenuItem *item = [self.statusItem.mainMenu deepestItemWithPath:feed.indexPath];
-	if (!item) {
+		if (item) block(feed, item);
-		[moc reset];
-		return;
 	}
-	block(feed, item);
 	[moc reset];
 }
 
 /// Callback method fired when feed has been updated in the background.
-- (void)feedUpdated:(NSNotification*)notify {
+- (void)articlesUpdated:(NSNotification*)notify {
 	[self updateFeedMenuItem:notify.object withBlock:^(Feed *feed, NSMenuItem *item) {
 		// 1. update in-memory unread count
 		UnreadTotal *updated = [UnreadTotal new];
@@ -154,8 +149,7 @@
 		[self.unreadMap updateAllCounts:updated forPath:feed.indexPath];
 		// 2. rebuild articles menu if it is open
 		if (item.submenu.isFeedMenu) { // menu item is visible
-			if (feed.group.name)
+			item.title = feed.group.anyName; // will replace (no title)
-				item.title = feed.group.name; // will replace (no title)
 			item.image = [feed iconImage16];
 			item.enabled = (feed.articles.count > 0);
 			if (item.submenu.numberOfItems > 0) { // replace articles menu