LoveLiveMusicPlayerKMP/iosApp/iosApp/InAppWebViewController.swift

import ComposeApp
import UIKit
import WebKit

/// 应用内网页（对齐 Android [WebViewActivity]），含广告过滤与页内导航。
final class InAppWebViewController: UIViewController {
    private let urlString: String
    private let pageTitle: String?
    private var webView: WKWebView?
    private let toolbar = UIToolbar()
    private let progressView = UIProgressView(progressViewStyle: .bar)
    private var progressObservation: NSKeyValueObservation?
    private var backButton: UIBarButtonItem!
    private var forwardButton: UIBarButtonItem!
    private var refreshButton: UIBarButtonItem!
    private var adCleanupTimer: Timer?

    init(url: String, title: String?) {
        urlString = url
        pageTitle = title
        super.init(nibName: nil, bundle: nil)
    }

    @available(*, unavailable)
    required init?(coder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }

    override func viewDidLoad() {
        super.viewDidLoad()
        view.backgroundColor = .systemBackground
        title = pageTitle?.isEmpty == false ? pageTitle : I18n.shared.t(key: "web_page")
        navigationItem.leftBarButtonItem = UIBarButtonItem(
            barButtonSystemItem: .close,
            target: self,
            action: #selector(closeTapped)
        )
        setupToolbar()
        setupProgressView()

        let config = WKWebViewConfiguration()
        let preferences = WKWebpagePreferences()
        preferences.allowsContentJavaScript = true
        config.defaultWebpagePreferences = preferences

        WebViewContentBlocker.configure(config, pageUrl: urlString) { [weak self] in
            guard let self else { return }
            let webView = WKWebView(frame: .zero, configuration: config)
            webView.navigationDelegate = self
            webView.allowsBackForwardNavigationGestures = true
            webView.translatesAutoresizingMaskIntoConstraints = false
            self.view.addSubview(webView)
            NSLayoutConstraint.activate([
                webView.topAnchor.constraint(equalTo: self.view.safeAreaLayoutGuide.topAnchor),
                webView.leadingAnchor.constraint(equalTo: self.view.leadingAnchor),
                webView.trailingAnchor.constraint(equalTo: self.view.trailingAnchor),
                webView.bottomAnchor.constraint(equalTo: self.toolbar.topAnchor),
            ])
            self.webView = webView
            self.view.bringSubviewToFront(self.progressView)
            self.observeProgress(webView)
            self.updateNavigationButtons()
            self.startAdCleanupTimer()
            guard let url = Self.resolveURL(self.urlString) else { return }
            webView.load(URLRequest(url: url))
        }
    }

    deinit {
        adCleanupTimer?.invalidate()
        progressObservation?.invalidate()
    }

    private func startAdCleanupTimer() {
        adCleanupTimer?.invalidate()
        adCleanupTimer = Timer.scheduledTimer(withTimeInterval: 1, repeats: true) { [weak self] _ in
            self?.webView?.evaluateJavaScript(WebViewAdBlock.shared.domCleanupScript(), completionHandler: nil)
        }
    }

    private func setupToolbar() {
        toolbar.translatesAutoresizingMaskIntoConstraints = false
        view.addSubview(toolbar)

        backButton = UIBarButtonItem(
            image: UIImage(systemName: "chevron.backward"),
            style: .plain,
            target: self,
            action: #selector(goBackTapped)
        )
        forwardButton = UIBarButtonItem(
            image: UIImage(systemName: "chevron.forward"),
            style: .plain,
            target: self,
            action: #selector(goForwardTapped)
        )
        refreshButton = UIBarButtonItem(
            barButtonSystemItem: .refresh,
            target: self,
            action: #selector(refreshTapped)
        )
        let flex = UIBarButtonItem(barButtonSystemItem: .flexibleSpace, target: nil, action: nil)
        toolbar.items = [backButton, flex, forwardButton, flex, refreshButton]

        NSLayoutConstraint.activate([
            toolbar.leadingAnchor.constraint(equalTo: view.leadingAnchor),
            toolbar.trailingAnchor.constraint(equalTo: view.trailingAnchor),
            toolbar.bottomAnchor.constraint(equalTo: view.safeAreaLayoutGuide.bottomAnchor),
        ])
    }

    private func setupProgressView() {
        progressView.progressViewStyle = .bar
        progressView.progressTintColor = .systemBlue
        progressView.trackTintColor = .clear
        progressView.progress = 0
        progressView.isHidden = true
        progressView.translatesAutoresizingMaskIntoConstraints = false

        let host: UIView = navigationController?.navigationBar ?? view
        host.addSubview(progressView)
        NSLayoutConstraint.activate([
            progressView.leadingAnchor.constraint(equalTo: host.leadingAnchor),
            progressView.trailingAnchor.constraint(equalTo: host.trailingAnchor),
            progressView.bottomAnchor.constraint(equalTo: host.bottomAnchor),
            progressView.heightAnchor.constraint(equalToConstant: 3),
        ])
    }

    private func observeProgress(_ webView: WKWebView) {
        progressObservation = webView.observe(\.estimatedProgress, options: [.new]) { [weak self] webView, _ in
            DispatchQueue.main.async {
                guard let self else { return }
                let progress = Float(webView.estimatedProgress)
                self.progressView.setProgress(progress, animated: true)
                self.progressView.isHidden = progress <= 0 || progress >= 1
            }
        }
    }

    private func updateNavigationButtons() {
        guard let webView else { return }
        backButton.isEnabled = webView.canGoBack
        forwardButton.isEnabled = webView.canGoForward
    }

    @objc private func closeTapped() {
        dismiss(animated: true)
    }

    @objc private func goBackTapped() {
        webView?.goBack()
    }

    @objc private func goForwardTapped() {
        webView?.goForward()
    }

    @objc private func refreshTapped() {
        webView?.reload()
    }

    private static func resolveURL(_ raw: String) -> URL? {
        let trimmed = raw.trimmingCharacters(in: .whitespacesAndNewlines)
        guard !trimmed.isEmpty else { return nil }
        if let url = URL(string: trimmed) { return url }
        if let encoded = trimmed.addingPercentEncoding(withAllowedCharacters: .urlFragmentAllowed) {
            return URL(string: encoded)
        }
        return nil
    }
}

extension InAppWebViewController: WKNavigationDelegate {
    func webView(_ webView: WKWebView, didStartProvisionalNavigation navigation: WKNavigation!) {
        progressView.progress = 0
        progressView.isHidden = false
        updateNavigationButtons()
    }

    func webView(_ webView: WKWebView, didFinish navigation: WKNavigation!) {
        progressView.isHidden = true
        updateNavigationButtons()
        webView.evaluateJavaScript(WebViewAdBlock.shared.domCleanupScript(), completionHandler: nil)
    }

    func webView(_ webView: WKWebView, didFail navigation: WKNavigation!, withError error: Error) {
        progressView.isHidden = true
        updateNavigationButtons()
    }

    func webView(_ webView: WKWebView, didFailProvisionalNavigation navigation: WKNavigation!, withError error: Error) {
        progressView.isHidden = true
        updateNavigationButtons()
    }
}