Initial

2025-12-04 15:13:22 +01:00
commit f8545f5c77
22 changed files with 3105 additions and 0 deletions
--- a/QLPreview/PreviewViewController.swift
+++ b/QLPreview/PreviewViewController.swift
@@ -0,0 +1,88 @@
+import Cocoa
+import Quartz // QLPreviewingController
+import WebKit // WebView
+import Markdown // Document, HTMLFormatter
+//import os // OSLog
+//
+//private let log = OSLog(subsystem: Bundle.main.bundleIdentifier!, category: "preview-plugin")
+
+extension URL {
+	/// Folder where user can mofifications to html template
+	static let UserModDir: URL? =
+		FileManager.default.urls(for: .documentDirectory, in: .userDomainMask).first
+	
+	/// Returns `true` if file or folder exists.
+	@inlinable func exists() -> Bool {
+		FileManager.default.fileExists(atPath: self.path)
+	}
+}
+
+
+class PreviewViewController: NSViewController, QLPreviewingController, WKNavigationDelegate {
+	var url: URL? = nil
+	var html: String? = nil
+	
+	override var nibName: NSNib.Name? {
+		return NSNib.Name("PreviewViewController")
+	}
+	
+	/// Load resource file either from user documents dir (if exists) or app bundle (default).
+	func bundleFile(filename: String, ext: String) throws -> URL {
+		if let userFile = URL.UserModDir?.appendingPathComponent(filename + "." + ext, isDirectory: false), userFile.exists() {
+			return userFile
+		}
+		return Bundle.main.url(forResource: filename, withExtension: ext)!
+	}
+	
+	func preparePreviewOfFile(at url: URL) async throws {
+		let cssUrl = try bundleFile(filename: "markdown", ext: "css")
+		let md = try Document(parsing: url)
+		self.url = url
+		self.html = """
+<!DOCTYPE html>
+<html lang="en">
+<head>
+<meta charset="UTF-8">
+<link rel="stylesheet" type="text/css" href="\(cssUrl)" />
+</head>
+<body class="markdown-body">
+\(HTMLFormatter.format(md))
+</body>
+</html>
+"""
+		// write debug output
+		//try? html!.write(to: URL.UserModDir!.appendingPathComponent("debug.html", isDirectory: false), atomically: true, encoding: .utf8)
+		
+		// create web view UI
+		let web = WKWebView(frame: self.view.bounds)
+		web.navigationDelegate = self
+		web.autoresizingMask = [.width, .height]
+		self.view.addSubview(web)
+		
+		// allow read access to all files under root "/"
+		let emtpy = Bundle.main.url(forResource: "empty", withExtension: "txt")!
+		web.loadFileURL(emtpy, allowingReadAccessTo: URL(string: "file:///")!)
+		
+		// loadHTMLString must wait until previous request is fully loaded
+		// see delegate method below
+	}
+	
+	func webView(_ webView: WKWebView, didFinish navigation: WKNavigation!) {
+		if webView.url?.lastPathComponent == "empty.txt" {
+			webView.loadHTMLString(html!, baseURL: url)
+			html = nil // free up memory
+		}
+	}
+	
+	// this should open links in external browser but it doesnt
+//	func webView(_ webView: WKWebView, decidePolicyFor navigationAction: WKNavigationAction, decisionHandler: @escaping @MainActor (WKNavigationActionPolicy) -> Void) {
+//		if navigationAction.navigationType == .linkActivated,
+//		   let url = navigationAction.request.url {
+//			os_log(.debug, log: log, "open url %{public}@", String(describing: url))
+//			NSWorkspace.shared.open(url)
+//			decisionHandler(.cancel)
+//		} else {
+//			decisionHandler(.allow)
+//		}
+//	}
+}