import SwiftUI
import WebKit

/// Montana Video — Video content browser
struct VideoView: View {
    @EnvironmentObject var engine: PresenceEngine
    @State private var showSidebar = false
    @State private var currentTitle = "Montana Video"
    @State private var isLoading = true
    @State private var canGoBack = false
    @State private var canGoForward = false

    private let gold = Color(red: 0.85, green: 0.68, blue: 0.25)
    private let videoURL = "https://efir.org"

    var body: some View {
        ZStack(alignment: .leading) {
            VStack(spacing: 0) {
                // ── BURGER MENU BUTTON ──
                HStack {
                    Button(action: { withAnimation(.easeInOut(duration: 0.3)) { showSidebar = true } }) {
                        Image(systemName: "line.3.horizontal")
                            .font(.system(size: 18, weight: .medium))
                            .foregroundColor(gold)
                            .padding(8)
                    }
                    .buttonStyle(.plain)
                    Spacer()
                }
                .padding(.horizontal, 12)
                .padding(.top, 8)

                // Navigation bar
                HStack(spacing: 8) {
                    Button(action: { NotificationCenter.default.post(name: .videoViewGoBack, object: nil) }) {
                        Image(systemName: "chevron.left")
                            .font(.system(size: 14, weight: .medium))
                            .foregroundColor(canGoBack ? gold : .secondary.opacity(0.4))
                    }
                    .buttonStyle(.plain)
                    .disabled(!canGoBack)

                    Button(action: { NotificationCenter.default.post(name: .videoViewGoForward, object: nil) }) {
                        Image(systemName: "chevron.right")
                            .font(.system(size: 14, weight: .medium))
                            .foregroundColor(canGoForward ? gold : .secondary.opacity(0.4))
                    }
                    .buttonStyle(.plain)
                    .disabled(!canGoForward)

                    Button(action: { NotificationCenter.default.post(name: .videoViewReload, object: nil) }) {
                        Image(systemName: isLoading ? "xmark" : "arrow.clockwise")
                            .font(.system(size: 12, weight: .medium))
                            .foregroundColor(gold)
                    }
                    .buttonStyle(.plain)

                    // Title bar
                    HStack(spacing: 6) {
                        Image(systemName: "play.circle.fill")
                            .font(.system(size: 12))
                            .foregroundColor(Color(red: 0.48, green: 0.18, blue: 1.0))

                        Text(currentTitle)
                            .font(.system(size: 12))
                            .foregroundColor(.primary)
                            .lineLimit(1)
                            .truncationMode(.tail)
                    }
                    .padding(.horizontal, 10)
                    .padding(.vertical, 6)
                    .frame(maxWidth: .infinity, alignment: .leading)
                    .background(Color(NSColor.controlBackgroundColor))
                    .cornerRadius(8)

                    Button(action: {
                        NotificationCenter.default.post(name: .videoViewLoadURL, object: videoURL)
                    }) {
                        Image(systemName: "house.fill")
                            .font(.system(size: 14))
                            .foregroundColor(gold)
                    }
                    .buttonStyle(.plain)
                }
                .padding(.horizontal, 12)
                .padding(.vertical, 6)

                Divider()

                // WebView for video content
                VideoWebView(
                    urlString: videoURL,
                    currentTitle: $currentTitle,
                    isLoading: $isLoading,
                    canGoBack: $canGoBack,
                    canGoForward: $canGoForward
                )
            }
            .background(Color(NSColor.windowBackgroundColor))

            // Sidebar overlay
            if showSidebar {
                Color.black.opacity(0.3)
                    .ignoresSafeArea()
                    .onTapGesture {
                        withAnimation(.easeInOut(duration: 0.3)) {
                            showSidebar = false
                        }
                    }

                SharedSidebar(isVisible: $showSidebar)
                    .transition(.move(edge: .leading))
            }
        }
    }
}

// MARK: - Video WebView Notifications

extension Notification.Name {
    static let videoViewGoBack = Notification.Name("videoViewGoBack")
    static let videoViewGoForward = Notification.Name("videoViewGoForward")
    static let videoViewReload = Notification.Name("videoViewReload")
    static let videoViewLoadURL = Notification.Name("videoViewLoadURL")
}

// MARK: - Video WKWebView Wrapper

struct VideoWebView: NSViewRepresentable {
    let urlString: String
    @Binding var currentTitle: String
    @Binding var isLoading: Bool
    @Binding var canGoBack: Bool
    @Binding var canGoForward: Bool

    func makeCoordinator() -> Coordinator {
        Coordinator(self)
    }

    func makeNSView(context: Context) -> WKWebView {
        let config = WKWebViewConfiguration()
        config.defaultWebpagePreferences.allowsContentJavaScript = true
        config.mediaTypesRequiringUserActionForPlayback = []

        let webView = WKWebView(frame: .zero, configuration: config)
        webView.navigationDelegate = context.coordinator
        context.coordinator.webView = webView

        if let url = URL(string: urlString) {
            webView.load(URLRequest(url: url))
        }

        let nc = NotificationCenter.default
        nc.addObserver(context.coordinator, selector: #selector(Coordinator.goBack), name: .videoViewGoBack, object: nil)
        nc.addObserver(context.coordinator, selector: #selector(Coordinator.goForward), name: .videoViewGoForward, object: nil)
        nc.addObserver(context.coordinator, selector: #selector(Coordinator.reload), name: .videoViewReload, object: nil)
        nc.addObserver(context.coordinator, selector: #selector(Coordinator.loadURL(_:)), name: .videoViewLoadURL, object: nil)

        webView.addObserver(context.coordinator, forKeyPath: #keyPath(WKWebView.canGoBack), options: .new, context: nil)
        webView.addObserver(context.coordinator, forKeyPath: #keyPath(WKWebView.canGoForward), options: .new, context: nil)
        webView.addObserver(context.coordinator, forKeyPath: #keyPath(WKWebView.isLoading), options: .new, context: nil)
        webView.addObserver(context.coordinator, forKeyPath: #keyPath(WKWebView.title), options: .new, context: nil)

        return webView
    }

    func updateNSView(_ nsView: WKWebView, context: Context) {}

    class Coordinator: NSObject, WKNavigationDelegate {
        var parent: VideoWebView
        weak var webView: WKWebView?

        init(_ parent: VideoWebView) {
            self.parent = parent
        }

        deinit {
            webView?.removeObserver(self, forKeyPath: #keyPath(WKWebView.canGoBack))
            webView?.removeObserver(self, forKeyPath: #keyPath(WKWebView.canGoForward))
            webView?.removeObserver(self, forKeyPath: #keyPath(WKWebView.isLoading))
            webView?.removeObserver(self, forKeyPath: #keyPath(WKWebView.title))
            NotificationCenter.default.removeObserver(self)
        }

        @objc func goBack() { webView?.goBack() }
        @objc func goForward() { webView?.goForward() }
        @objc func reload() {
            if webView?.isLoading == true {
                webView?.stopLoading()
            } else {
                webView?.reload()
            }
        }
        @objc func loadURL(_ notification: Notification) {
            if let urlStr = notification.object as? String, let url = URL(string: urlStr) {
                webView?.load(URLRequest(url: url))
            }
        }

        override func observeValue(forKeyPath keyPath: String?, of object: Any?, change: [NSKeyValueChangeKey: Any]?, context: UnsafeMutableRawPointer?) {
            guard let webView = webView else { return }
            DispatchQueue.main.async {
                self.parent.canGoBack = webView.canGoBack
                self.parent.canGoForward = webView.canGoForward
                self.parent.isLoading = webView.isLoading
                self.parent.currentTitle = webView.title ?? webView.url?.host ?? "Montana Video"
            }
        }

        func webView(_ webView: WKWebView, didFinish navigation: WKNavigation!) {
            DispatchQueue.main.async {
                self.parent.isLoading = false
                self.parent.currentTitle = webView.title ?? webView.url?.host ?? "Montana Video"
            }
        }
    }
}

// MARK: - Preview

#Preview {
    VideoView()
        .environmentObject(PresenceEngine.shared)
        .frame(width: 600, height: 500)
}