import UIKit

class TVCFilter: UITableViewController, EditActionsRemove {
	var currentFilter: FilterOptions = .none // set by segue
	private lazy var dataSource = DomainFilter.list(where: currentFilter)
	
	override func viewDidLoad() {
		super.viewDidLoad()
		NotifyDNSFilterChanged.observe(call: #selector(didChangeDomainFilter), on: self)
	}
	
	@objc func didChangeDomainFilter(_ notification: Notification) {
		guard let domain = notification.object as? String else {
			preconditionFailure("Domain independent filter reset not implemented")
		}
		if DomainFilter[domain]?.contains(currentFilter) ?? false {
			let i = dataSource.binTreeIndex(of: domain, compare: (<))!
			if i >= dataSource.count || dataSource[i] != domain {
				dataSource.insert(domain, at: i)
				tableView.safeInsertRow(i)
			}
		} else if let i = dataSource.binTreeRemove(domain, compare: (<)) {
			tableView.safeDeleteRows([i])
		}
	}
	
	@IBAction private func addNewFilter() {
		let alert = AskAlert(title: "Create new filter",
							 text: "Enter the domain name you wish to add.",
							 buttonText: "Add") {
			guard let dom = $0.textFields?.first?.text?.lowercased() else {
				return
			}
			guard dom.contains("."), !dom.isKnownSLD() else {
				ErrorAlert("Entered domain is not valid. Filter can't match country TLD only.").presentIn(self)
				return
			}
			DomainFilter.update(dom, add: self.currentFilter)
		}
		alert.addTextField {
			$0.placeholder = "cdn.domain.tld"
			$0.keyboardType = .URL
		}
		alert.presentIn(self)
	}
	
	// MARK: - Table View Data Source
	
	override func tableView(_ _: UITableView, numberOfRowsInSection _: Int) -> Int { dataSource.count }
	
	override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
		let cell = tableView.dequeueReusableCell(withIdentifier: "DomainFilterCell")!
		cell.textLabel?.text = dataSource[indexPath.row]
		return cell
	}
	
	// MARK: - Editing
	
	override func tableView(_ tableView: UITableView, editActionsForRowAt indexPath: IndexPath) -> [UITableViewRowAction]? {
		getRowActionsIOS9(indexPath, tableView)
	}
	@available(iOS 11.0, *)
	override func tableView(_ tableView: UITableView, trailingSwipeActionsConfigurationForRowAt indexPath: IndexPath) -> UISwipeActionsConfiguration? {
		getRowActionsIOS11(indexPath)
	}
	
	func editableRowCallback(_ index: IndexPath, _ action: RowAction, _ userInfo: Any?) -> Bool {
		let domain = dataSource[index.row]
		DomainFilter.update(domain, remove: currentFilter)
		return true
	}
	
	// MARK: - Long Press Gesture
	
	private var cellMenu = TableCellTapMenu()
	private var copyDomain: String? = nil
		
	override func tableView(_ tableView: UITableView, willSelectRowAt indexPath: IndexPath) -> IndexPath? {
		if cellMenu.start(tableView, indexPath) {
			copyDomain = cellMenu.getSelected(dataSource)
			self.becomeFirstResponder()
		}
		return nil
	}
	
	override var canBecomeFirstResponder: Bool { true }
	
	override func copy(_ sender: Any?) {
		if let dom = copyDomain {
			UIPasteboard.general.string = dom
		}
		cellMenu.reset()
		copyDomain = nil
	}
}