Implement ArticleView for macOS

2025-08-12 06:26:36 +00:00 · 2020-07-08 10:20:04 -05:00
parent 909dcb3f93
commit 6f055b5923
6 changed files with 372 additions and 24 deletions
--- a/Multiplatform/macOS/Article/WebViewController.swift
+++ b/Multiplatform/macOS/Article/WebViewController.swift
@@ -0,0 +1,330 @@
+//
+//  WebViewController.swift
+//  Multiplatform macOS
+//
+//  Created by Maurice Parker on 7/8/20.
+//  Copyright © 2020 Ranchero Software. All rights reserved.
+//
+
+import AppKit
+import Articles
+
+import AppKit
+import RSCore
+import Articles
+
+extension Notification.Name {
+	static let appleColorPreferencesChangedNotification = Notification.Name("AppleColorPreferencesChangedNotification")
+	static let appleInterfaceThemeChangedNotification = Notification.Name("AppleInterfaceThemeChangedNotification")
+}
+
+protocol WebViewControllerDelegate: class {
+	func webViewController(_: WebViewController, articleExtractorButtonStateDidUpdate: ArticleExtractorButtonState)
+}
+
+class WebViewController: NSViewController {
+	
+	private struct MessageName {
+		static let imageWasClicked = "imageWasClicked"
+		static let imageWasShown = "imageWasShown"
+		static let showFeedInspector = "showFeedInspector"
+	}
+	
+	private var webView: PreloadedWebView?
+	
+	private var articleExtractor: ArticleExtractor? = nil
+	var extractedArticle: ExtractedArticle?
+	var isShowingExtractedArticle = false
+
+	var articleExtractorButtonState: ArticleExtractorButtonState = .off {
+		didSet {
+			delegate?.webViewController(self, articleExtractorButtonStateDidUpdate: articleExtractorButtonState)
+		}
+	}
+	
+	var articleModel: ArticleModel?
+	weak var delegate: WebViewControllerDelegate?
+	
+	var article: Article?
+	
+	override func loadView() {
+		view = NSView()
+	}
+	
+	override func viewDidLoad() {
+		super.viewDidLoad()
+
+		NotificationCenter.default.addObserver(self, selector: #selector(webFeedIconDidBecomeAvailable(_:)), name: .WebFeedIconDidBecomeAvailable, object: nil)
+		NotificationCenter.default.addObserver(self, selector: #selector(avatarDidBecomeAvailable(_:)), name: .AvatarDidBecomeAvailable, object: nil)
+		NotificationCenter.default.addObserver(self, selector: #selector(faviconDidBecomeAvailable(_:)), name: .FaviconDidBecomeAvailable, object: nil)
+		DistributedNotificationCenter.default().addObserver(self, selector: #selector(appleColorPreferencesChanged(_:)), name: .appleColorPreferencesChangedNotification, object: nil)
+		DistributedNotificationCenter.default().addObserver(self, selector: #selector(appleInterfaceThemeChanged(_:)), name: .appleInterfaceThemeChangedNotification, object: nil)
+		
+		loadWebView()
+	}
+
+	// MARK: Notifications
+	
+	@objc func webFeedIconDidBecomeAvailable(_ note: Notification) {
+		reloadArticleImage()
+	}
+
+	@objc func avatarDidBecomeAvailable(_ note: Notification) {
+		reloadArticleImage()
+	}
+
+	@objc func faviconDidBecomeAvailable(_ note: Notification) {
+		reloadArticleImage()
+	}
+
+	@objc func appleColorPreferencesChanged(_ note: Notification) {
+		loadWebView()
+	}
+	
+	@objc func appleInterfaceThemeChanged(_ note: Notification) {
+		loadWebView()
+	}
+	
+	// MARK: API
+	
+	func focus() {
+		webView?.becomeFirstResponder()
+	}
+
+	func canScrollDown(_ completion: @escaping (Bool) -> Void) {
+		fetchScrollInfo { (scrollInfo) in
+			completion(scrollInfo?.canScrollDown ?? false)
+		}
+	}
+
+	override func scrollPageDown(_ sender: Any?) {
+		webView?.scrollPageDown(sender)
+	}
+	
+	func toggleArticleExtractor() {
+
+		guard let article = article else {
+			return
+		}
+
+		guard articleExtractor?.state != .processing else {
+			stopArticleExtractor()
+			loadWebView()
+			return
+		}
+
+		guard !isShowingExtractedArticle else {
+			isShowingExtractedArticle = false
+			loadWebView()
+			articleExtractorButtonState = .off
+			return
+		}
+
+		if let articleExtractor = articleExtractor {
+			if article.preferredLink == articleExtractor.articleLink {
+				isShowingExtractedArticle = true
+				loadWebView()
+				articleExtractorButtonState = .on
+			}
+		} else {
+			startArticleExtractor()
+		}
+
+	}
+	
+	func stopArticleExtractorIfProcessing() {
+		if articleExtractor?.state == .processing {
+			stopArticleExtractor()
+		}
+	}
+
+	func stopWebViewActivity() {
+		if let webView = webView {
+			stopMediaPlayback(webView)
+		}
+	}
+
+}
+
+// MARK: ArticleExtractorDelegate
+
+extension WebViewController: ArticleExtractorDelegate {
+
+	func articleExtractionDidFail(with: Error) {
+		stopArticleExtractor()
+		articleExtractorButtonState = .error
+		loadWebView()
+	}
+
+	func articleExtractionDidComplete(extractedArticle: ExtractedArticle) {
+		if articleExtractor?.state != .cancelled {
+			self.extractedArticle = extractedArticle
+			isShowingExtractedArticle = true
+			loadWebView()
+			articleExtractorButtonState = .on
+		}
+	}
+
+}
+
+
+// MARK: WKScriptMessageHandler
+
+extension WebViewController: WKScriptMessageHandler {
+
+	func userContentController(_ userContentController: WKUserContentController, didReceive message: WKScriptMessage) {
+		switch message.name {
+		case MessageName.imageWasShown:
+			return
+		case MessageName.imageWasClicked:
+			return
+		case MessageName.showFeedInspector:
+			return
+		default:
+			return
+		}
+	}
+	
+}
+
+// MARK: Private
+
+private extension WebViewController {
+
+	func loadWebView() {
+		if let webView = webView {
+			self.renderPage(webView)
+			return
+		}
+		
+		articleModel?.webViewProvider?.dequeueWebView() { webView in
+			
+			// Add the webview
+			webView.translatesAutoresizingMaskIntoConstraints = false
+			self.view.addSubview(webView)
+			NSLayoutConstraint.activate([
+				self.view.leadingAnchor.constraint(equalTo: webView.leadingAnchor),
+				self.view.trailingAnchor.constraint(equalTo: webView.trailingAnchor),
+				self.view.topAnchor.constraint(equalTo: webView.topAnchor),
+				self.view.bottomAnchor.constraint(equalTo: webView.bottomAnchor)
+			])
+		
+			webView.configuration.userContentController.add(WrapperScriptMessageHandler(self), name: MessageName.imageWasClicked)
+			webView.configuration.userContentController.add(WrapperScriptMessageHandler(self), name: MessageName.imageWasShown)
+			webView.configuration.userContentController.add(WrapperScriptMessageHandler(self), name: MessageName.showFeedInspector)
+
+			self.renderPage(webView)
+			
+		}
+		
+	}
+
+	func renderPage(_ webView: PreloadedWebView) {
+		let style = ArticleStylesManager.shared.currentStyle
+		let rendering: ArticleRenderer.Rendering
+
+		if let articleExtractor = articleExtractor, articleExtractor.state == .processing {
+			rendering = ArticleRenderer.loadingHTML(style: style)
+		} else if let articleExtractor = articleExtractor, articleExtractor.state == .failedToParse, let article = article {
+			rendering = ArticleRenderer.articleHTML(article: article, style: style)
+		} else if let article = article, let extractedArticle = extractedArticle {
+			if isShowingExtractedArticle {
+				rendering = ArticleRenderer.articleHTML(article: article, extractedArticle: extractedArticle, style: style)
+			} else {
+				rendering = ArticleRenderer.articleHTML(article: article, style: style)
+			}
+		} else if let article = article {
+			rendering = ArticleRenderer.articleHTML(article: article, style: style)
+		} else {
+			rendering = ArticleRenderer.noSelectionHTML(style: style)
+		}
+		
+		let substitutions = [
+			"title": rendering.title,
+			"baseURL": rendering.baseURL,
+			"style": rendering.style,
+			"body": rendering.html
+		]
+
+		let html = try! MacroProcessor.renderedText(withTemplate: ArticleRenderer.page.html, substitutions: substitutions)
+		webView.loadHTMLString(html, baseURL: ArticleRenderer.page.baseURL)
+		
+	}
+
+	func fetchScrollInfo(_ completion: @escaping (ScrollInfo?) -> Void) {
+		guard let webView = webView else {
+			completion(nil)
+			return
+		}
+		
+		let javascriptString = "var x = {contentHeight: document.body.scrollHeight, offsetY: window.pageYOffset}; x"
+
+		webView.evaluateJavaScript(javascriptString) { (info, error) in
+			guard let info = info as? [String: Any] else {
+				completion(nil)
+				return
+			}
+			guard let contentHeight = info["contentHeight"] as? CGFloat, let offsetY = info["offsetY"] as? CGFloat else {
+				completion(nil)
+				return
+			}
+
+			let scrollInfo = ScrollInfo(contentHeight: contentHeight, viewHeight: webView.frame.height, offsetY: offsetY)
+			completion(scrollInfo)
+		}
+	}
+	
+	func startArticleExtractor() {
+		if let link = article?.preferredLink, let extractor = ArticleExtractor(link) {
+			extractor.delegate = self
+			extractor.process()
+			articleExtractor = extractor
+			articleExtractorButtonState = .animated
+		}
+	}
+
+	func stopArticleExtractor() {
+		articleExtractor?.cancel()
+		articleExtractor = nil
+		isShowingExtractedArticle = false
+		articleExtractorButtonState = .off
+	}
+
+	func reloadArticleImage() {
+		guard let article = article else { return }
+
+		var components = URLComponents()
+		components.scheme = ArticleRenderer.imageIconScheme
+		components.path = article.articleID
+		
+		if let imageSrc = components.string {
+			webView?.evaluateJavaScript("reloadArticleImage(\"\(imageSrc)\")")
+		}
+	}
+	
+	func stopMediaPlayback(_ webView: WKWebView) {
+		webView.evaluateJavaScript("stopMediaPlayback();")
+	}
+	
+}
+
+// MARK: - ScrollInfo
+
+private struct ScrollInfo {
+
+	let contentHeight: CGFloat
+	let viewHeight: CGFloat
+	let offsetY: CGFloat
+	let canScrollDown: Bool
+	let canScrollUp: Bool
+
+	init(contentHeight: CGFloat, viewHeight: CGFloat, offsetY: CGFloat) {
+		self.contentHeight = contentHeight
+		self.viewHeight = viewHeight
+		self.offsetY = offsetY
+
+		self.canScrollDown = viewHeight + offsetY < contentHeight
+		self.canScrollUp = offsetY > 0.1
+	}
+	
+}