pageta-native/ShareExtension/ShareViewController.swift

import UIKit
import UniformTypeIdentifiers

/// Pageta ShareExtension — fängt URLs aus Safari/Mail/anderen Apps,
/// schreibt sie in den App-Group `PendingShareStore`. App synct
/// asynchron beim nächsten Foreground zum Server (Pattern wie
/// herbatrium-native η-8.3, aber mit sichtbarem Toast).
///
/// Bewusst kein Server-Roundtrip in der Extension selbst: 30s-Limit für
/// App-Extensions + kein JWT-Refresh-Pfad ohne den vollen AuthClient.
/// Queue → asynchroner Drain im App-Context ist sauberer.
///
/// **UX:** im Gegensatz zu herbatrium (silent dismiss → User landet im
/// Foto-Flow) zeigt Pageta ein kurzes ✓-Toast (~0.8 s), weil die App
/// danach nicht zwingend geöffnet wird. Ohne sichtbares Feedback wirkt
/// das Share wie abgebrochen.
@objc(ShareViewController)
final class ShareViewController: UIViewController {
	private let store = PendingShareStore()

	private let toastCard = UIView()
	private let iconView = UIImageView()
	private let statusLabel = UILabel()

	// Paper-Theme-Tokens (inline gehalten — die App-Side hat sie in
	// PagetaTheme.swift, aber Extensions haben keinen Zugriff auf die
	// Sources/-Targets). Bei Theme-Updates beide Stellen anpassen.
	private static let paperCream = UIColor(red: 0.961, green: 0.937, blue: 0.902, alpha: 1.0)
	private static let paperSepia = UIColor(red: 0.227, green: 0.176, blue: 0.125, alpha: 1.0)
	private static let paperTerracotta = UIColor(red: 0.588, green: 0.306, blue: 0.165, alpha: 1.0)

	override func viewDidLoad() {
		super.viewDidLoad()
		view.backgroundColor = UIColor.black.withAlphaComponent(0.25)
		setupToast()
	}

	override func viewDidAppear(_ animated: Bool) {
		super.viewDidAppear(animated)
		UIView.animate(withDuration: 0.18) {
			self.toastCard.alpha = 1
			self.toastCard.transform = .identity
		}
		Task { await handleSharedContent() }
	}

	private func setupToast() {
		toastCard.backgroundColor = Self.paperCream
		toastCard.layer.cornerRadius = 16
		toastCard.layer.shadowColor = UIColor.black.cgColor
		toastCard.layer.shadowOpacity = 0.18
		toastCard.layer.shadowRadius = 14
		toastCard.layer.shadowOffset = CGSize(width: 0, height: 4)
		toastCard.alpha = 0
		toastCard.transform = CGAffineTransform(scaleX: 0.94, y: 0.94)
		toastCard.translatesAutoresizingMaskIntoConstraints = false

		iconView.contentMode = .scaleAspectFit
		iconView.tintColor = Self.paperTerracotta
		iconView.preferredSymbolConfiguration = UIImage.SymbolConfiguration(pointSize: 36, weight: .regular)
		iconView.translatesAutoresizingMaskIntoConstraints = false

		statusLabel.font = .systemFont(ofSize: 15, weight: .medium)
		statusLabel.textColor = Self.paperSepia
		statusLabel.textAlignment = .center
		statusLabel.numberOfLines = 0
		statusLabel.text = "Speichere …"
		statusLabel.translatesAutoresizingMaskIntoConstraints = false

		view.addSubview(toastCard)
		toastCard.addSubview(iconView)
		toastCard.addSubview(statusLabel)

		NSLayoutConstraint.activate([
			toastCard.centerXAnchor.constraint(equalTo: view.centerXAnchor),
			toastCard.centerYAnchor.constraint(equalTo: view.centerYAnchor),
			toastCard.widthAnchor.constraint(equalToConstant: 260),

			iconView.topAnchor.constraint(equalTo: toastCard.topAnchor, constant: 22),
			iconView.centerXAnchor.constraint(equalTo: toastCard.centerXAnchor),
			iconView.widthAnchor.constraint(equalToConstant: 44),
			iconView.heightAnchor.constraint(equalToConstant: 44),

			statusLabel.topAnchor.constraint(equalTo: iconView.bottomAnchor, constant: 12),
			statusLabel.leadingAnchor.constraint(equalTo: toastCard.leadingAnchor, constant: 20),
			statusLabel.trailingAnchor.constraint(equalTo: toastCard.trailingAnchor, constant: -20),
			statusLabel.bottomAnchor.constraint(equalTo: toastCard.bottomAnchor, constant: -22),
		])

		// Placeholder-Icon, wird in showResult getauscht.
		iconView.image = UIImage(systemName: "tray.and.arrow.down")
	}

	private func handleSharedContent() async {
		guard let extensionItems = extensionContext?.inputItems as? [NSExtensionItem] else {
			await showResult(.noURL)
			return
		}

		var foundURL: URL?
		var foundHTML: String?
		// Property-List (JS-Preprocessing aus Safari) zuerst — sie trägt das
		// gerenderte HTML der zustimmenden Seite. URL/Text sind der Fallback
		// für nackte Shares aus anderen Apps. Kein early-break: HTML und URL
		// kommen als getrennte Provider.
		for item in extensionItems {
			guard let attachments = item.attachments else { continue }
			for provider in attachments {
				if provider.hasItemConformingToTypeIdentifier(UTType.propertyList.identifier) {
					if let result = await loadPreprocessed(from: provider) {
						foundHTML = result.html
						foundURL = foundURL ?? result.url
					}
				} else if provider.hasItemConformingToTypeIdentifier(UTType.url.identifier) {
					if foundURL == nil, let url = await loadURL(from: provider) {
						foundURL = url
					}
				} else if provider.hasItemConformingToTypeIdentifier(UTType.plainText.identifier) {
					if foundURL == nil, let url = await loadURLFromText(provider) {
						foundURL = url
					}
				}
			}
		}

		guard let url = foundURL else {
			await showResult(.noURL)
			return
		}
		// Gerendertes HTML (falls aus Safari) in den App-Group-Store legen,
		// damit die App es bei der Extraktion gegen Consent-Wände nutzen kann.
		if let html = foundHTML {
			SharedHTMLStore().put(html, for: url)
		}
		// Enqueuen — die App speichert local-first beim nächsten Foreground
		// (auch ausgeloggt; Extraktion + Account-Claim laufen später nach).
		// Darum ist „hinzugefügt" hier ehrlich, kein Login nötig.
		store.enqueue(url)
		await showResult(.saved)
	}

	/// Liest das JS-Preprocessing-Ergebnis (Safari liefert es als
	/// Property-List unter `NSExtensionJavaScriptPreprocessingResultsKey`).
	private func loadPreprocessed(from provider: NSItemProvider) async -> (url: URL?, html: String?)? {
		await withCheckedContinuation { continuation in
			provider.loadItem(forTypeIdentifier: UTType.propertyList.identifier, options: nil) { item, _ in
				guard let dict = item as? NSDictionary,
				      let results = dict[NSExtensionJavaScriptPreprocessingResultsKey] as? NSDictionary
				else {
					continuation.resume(returning: nil)
					return
				}
				let html = results["html"] as? String
				let url = (results["url"] as? String).flatMap { URL(string: $0) }
				continuation.resume(returning: (url, html))
			}
		}
	}

	private func loadURL(from provider: NSItemProvider) async -> URL? {
		await withCheckedContinuation { continuation in
			provider.loadItem(forTypeIdentifier: UTType.url.identifier, options: nil) { item, _ in
				if let url = item as? URL {
					continuation.resume(returning: url)
				} else if let data = item as? Data,
				          let str = String(data: data, encoding: .utf8),
				          let url = URL(string: str) {
					continuation.resume(returning: url)
				} else {
					continuation.resume(returning: nil)
				}
			}
		}
	}

	private func loadURLFromText(_ provider: NSItemProvider) async -> URL? {
		await withCheckedContinuation { continuation in
			provider.loadItem(forTypeIdentifier: UTType.plainText.identifier, options: nil) { item, _ in
				if let text = item as? String,
				   let detector = try? NSDataDetector(types: NSTextCheckingResult.CheckingType.link.rawValue),
				   let match = detector.firstMatch(in: text, range: NSRange(text.startIndex..., in: text)),
				   let url = match.url
				{
					continuation.resume(returning: url)
				} else {
					continuation.resume(returning: nil)
				}
			}
		}
	}

	@MainActor
	private func showResult(_ outcome: ShareOutcome) async {
		let dwellMillis: Int
		switch outcome {
		case .saved:
			iconView.image = UIImage(systemName: "checkmark.circle.fill")
			iconView.tintColor = Self.paperTerracotta
			statusLabel.text = "Zum Stapel hinzugefügt"
			dwellMillis = 700
		case .noURL:
			iconView.image = UIImage(systemName: "exclamationmark.triangle.fill")
			iconView.tintColor = .systemOrange
			statusLabel.text = "Keine URL gefunden"
			dwellMillis = 700
		}
		try? await Task.sleep(for: .milliseconds(dwellMillis))
		UIView.animate(withDuration: 0.2) {
			self.toastCard.alpha = 0
			self.toastCard.transform = CGAffineTransform(scaleX: 0.96, y: 0.96)
			self.view.backgroundColor = UIColor.black.withAlphaComponent(0)
		}
		try? await Task.sleep(for: .milliseconds(200))
		extensionContext?.completeRequest(returningItems: nil, completionHandler: nil)
	}
}