import SwiftData
import SwiftUI

/// Full settings window using macOS native TabView.
/// Contains: Mix Targets, Appearance (themes), Playlist (columns, artwork, grouping), Playback, General.
struct SettingsView: View {
    var body: some View {
        TabView {
            MixTargetSettings()
                .tabItem {
                    Label("Mix Targets", systemImage: "target")
                }

            ChadMusicSettings()
                .tabItem {
                    Label("Chad Music", systemImage: "cloud.fill")
                }

            AppearanceSettings()
                .tabItem {
                    Label("Appearance", systemImage: "paintbrush")
                }

            PlaylistSettings()
                .tabItem {
                    Label("Playlist", systemImage: "list.bullet")
                }

            PlaybackSettings()
                .tabItem {
                    Label("Playback", systemImage: "play.circle")
                }

            KeyboardShortcutSettings()
                .tabItem {
                    Label("Shortcuts", systemImage: "keyboard")
                }

            GeneralSettings()
                .tabItem {
                    Label("General", systemImage: "gearshape")
                }
        }
        .frame(width: 580, height: 500)
    }
}

// MARK: - Mix Colors (shared across views)

/// The 3 mix target colors: Red, Blue, Gold.
let mixTargetColors: [Color] = [
    Color(red: 0.95, green: 0.3, blue: 0.3),   // Red
    Color(red: 0.3, green: 0.75, blue: 0.95),   // Blue
    Color(red: 0.95, green: 0.75, blue: 0.2),   // Yellow/Gold
]

// MARK: - Mix Target Settings

private struct MixTargetSettings: View {
    @Environment(PlaylistViewModel.self) private var playlistVM
    @EnvironmentObject private var theme: AppTheme
    @ObservedObject private var shortcutConfig = KeyboardShortcutConfig.shared
    @Query(sort: \Playlist.dateModified, order: .reverse) private var playlists: [Playlist]

    private let mixActions: [ShortcutAction] = [.addToMix1, .addToMix2, .addToMix3]

    var body: some View {
        VStack(alignment: .leading, spacing: 20) {
            Text("Mix Targets")
                .font(.title3.bold())

            Text("Assign playlists to the 3 mix slots. Use the configured shortcuts to quick-add the current track, or click the numbered buttons at the top of the window.")
                .font(.callout)
                .foregroundStyle(.secondary)

            VStack(spacing: 12) {
                ForEach(0..<3, id: \.self) { slot in
                    HStack(spacing: 12) {
                        // Colored number badge
                        Text("\(slot + 1)")
                            .font(.system(size: 14, weight: .bold, design: .rounded))
                            .frame(width: 30, height: 30)
                            .foregroundStyle(mixTargetColors[slot])
                            .background(mixTargetColors[slot].opacity(0.15))
                            .clipShape(RoundedRectangle(cornerRadius: 6))

                        // Playlist picker — Picker with menu style for full-width clickability
                        Picker(selection: Binding(
                            get: { playlistVM.mixTargets[slot]?.id },
                            set: { newID in
                                if let newID, let playlist = playlists.first(where: { $0.id == newID }) {
                                    playlistVM.setMixTarget(slot, playlist: playlist)
                                } else {
                                    playlistVM.setMixTarget(slot, playlist: nil)
                                }
                            }
                        )) {
                            Text("Not set").tag(UUID?.none)
                            Divider()
                            ForEach(playlists) { playlist in
                                Text(playlist.name).tag(Optional(playlist.id))
                            }
                        } label: {
                            EmptyView()
                        }
                        .labelsHidden()
                        .frame(minWidth: 160)

                        // Shortcut hint
                        Text(shortcutConfig.binding(for: mixActions[slot]).displayString)
                            .font(.system(size: 11, design: .monospaced))
                            .foregroundStyle(.secondary)
                            .frame(width: 50)
                    }
                }
            }

            Divider()

            Text("Tip: You can also right-click a playlist in the sidebar to assign it to a mix slot.")
                .font(.callout)
                .foregroundStyle(.secondary)

            Spacer()
        }
        .padding(24)
    }
}

// MARK: - Appearance Settings (Theme/Skin picker)

private struct AppearanceSettings: View {
    @EnvironmentObject private var theme: AppTheme
    @ObservedObject private var iconConfig = AppIconConfig.shared

    private let modernSkins: [AppTheme.Skin] = [.dark, .midnight, .forest, .ocean, .warm, .light]
    private let retroSkins: [AppTheme.Skin] = [.winampClassic, .winampModern, .foobarDark, .foobarLight, .win95, .win98, .xpLuna, .macOSClassic]

    var body: some View {
        ScrollView {
            VStack(alignment: .leading, spacing: 20) {
                // MARK: - App Icon Color
                Text("App Icon")
                    .font(.title3.bold())

                Text("Choose an accent color for the Dock icon.")
                    .font(.callout)
                    .foregroundStyle(.secondary)

                ScrollView(.horizontal, showsIndicators: false) {
                    HStack(spacing: 12) {
                        ForEach(AppIconConfig.iconColors) { option in
                            Button {
                                iconConfig.selectedColorName = option.name
                            } label: {
                                VStack(spacing: 6) {
                                    RoundedRectangle(cornerRadius: 12)
                                        .fill(option.color)
                                        .frame(width: 50, height: 50)
                                        .overlay(
                                            RoundedRectangle(cornerRadius: 12)
                                                .stroke(
                                                    iconConfig.selectedColorName == option.name
                                                        ? Color.accentColor : Color.white.opacity(0.2),
                                                    lineWidth: iconConfig.selectedColorName == option.name ? 2.5 : 1
                                                )
                                        )
                                        .overlay {
                                            if iconConfig.selectedColorName == option.name {
                                                Image(systemName: "checkmark")
                                                    .font(.system(size: 16, weight: .bold))
                                                    .foregroundStyle(.white)
                                                    .shadow(radius: 2)
                                            }
                                        }
                                    Text(option.name)
                                        .font(.caption2)
                                        .foregroundStyle(.secondary)
                                }
                            }
                            .buttonStyle(.plain)
                        }
                    }
                    .padding(.vertical, 4)
                }

                Divider()

                // MARK: - Theme
                Text("Theme")
                    .font(.title3.bold())

                Text("Choose a visual theme for MixBoard. Each theme enforces its own light/dark appearance.")
                    .font(.callout)
                    .foregroundStyle(.secondary)

                // Modern
                VStack(alignment: .leading, spacing: 8) {
                    Text("Modern")
                        .font(.headline)
                        .foregroundStyle(.secondary)

                    LazyVGrid(columns: [GridItem(.adaptive(minimum: 150))], spacing: 8) {
                        ForEach(modernSkins) { skin in
                            SkinCard(skin: skin, isSelected: theme.currentSkin == skin) {
                                withAnimation(.easeInOut(duration: 0.2)) {
                                    theme.currentSkin = skin
                                }
                            }
                        }
                    }
                }

                Divider()

                // Retro
                VStack(alignment: .leading, spacing: 8) {
                    Text("Retro")
                        .font(.headline)
                        .foregroundStyle(.secondary)

                    LazyVGrid(columns: [GridItem(.adaptive(minimum: 150))], spacing: 8) {
                        ForEach(retroSkins) { skin in
                            SkinCard(skin: skin, isSelected: theme.currentSkin == skin) {
                                withAnimation(.easeInOut(duration: 0.2)) {
                                    theme.currentSkin = skin
                                }
                            }
                        }
                    }
                }
            }
            .padding(24)
        }
    }
}

/// A compact card showing a skin preview swatch and name.
private struct SkinCard: View {
    let skin: AppTheme.Skin
    let isSelected: Bool
    let action: () -> Void

    var body: some View {
        Button(action: action) {
            HStack(spacing: 10) {
                // Color swatch showing the skin's approximate palette
                RoundedRectangle(cornerRadius: 4)
                    .fill(skin.previewColor)
                    .frame(width: 28, height: 28)
                    .overlay {
                        if skin.colorScheme == .dark {
                            Image(systemName: "moon.fill")
                                .font(.system(size: 10))
                                .foregroundStyle(.white.opacity(0.7))
                        } else {
                            Image(systemName: "sun.max.fill")
                                .font(.system(size: 10))
                                .foregroundStyle(.black.opacity(0.5))
                        }
                    }

                VStack(alignment: .leading, spacing: 1) {
                    Text(skin.rawValue)
                        .font(.system(size: 12, weight: .medium))
                        .lineLimit(1)
                    Text(skin.colorScheme == .dark ? "Dark" : "Light")
                        .font(.system(size: 10))
                        .foregroundStyle(.secondary)
                }

                Spacer(minLength: 0)

                if isSelected {
                    Image(systemName: "checkmark.circle.fill")
                        .foregroundStyle(.green)
                        .font(.system(size: 14))
                }
            }
            .padding(8)
            .background(isSelected ? Color.accentColor.opacity(0.1) : Color.clear)
            .overlay(
                RoundedRectangle(cornerRadius: 8)
                    .stroke(isSelected ? Color.accentColor : Color.gray.opacity(0.3), lineWidth: isSelected ? 2 : 1)
            )
            .clipShape(RoundedRectangle(cornerRadius: 8))
            .contentShape(Rectangle())
        }
        .buttonStyle(.plain)
    }
}

// MARK: - Playlist Settings (Columns, Artwork, Grouping)

private struct PlaylistSettings: View {
    @ObservedObject private var viewConfig = PlaylistViewConfig.shared

    var body: some View {
        ScrollView {
            VStack(alignment: .leading, spacing: 20) {
                // Visible columns
                VStack(alignment: .leading, spacing: 8) {
                    HStack {
                        Text("Visible Columns")
                            .font(.title3.bold())
                        Spacer()
                        Button("Reset to Defaults") {
                            viewConfig.resetToDefaults()
                        }
                        .font(.caption)
                    }

                    Text("Select which columns appear in the playlist view.")
                        .font(.callout)
                        .foregroundStyle(.secondary)

                    LazyVGrid(columns: [GridItem(.adaptive(minimum: 130))], spacing: 6) {
                        ForEach(PlaylistViewConfig.Column.allCases) { column in
                            Toggle(column.rawValue, isOn: Binding(
                                get: { viewConfig.isColumnVisible(column) },
                                set: { _ in viewConfig.toggleColumn(column) }
                            ))
                            .toggleStyle(.checkbox)
                            .font(.system(size: 12))
                        }
                    }
                }

                Divider()

                // Artwork
                VStack(alignment: .leading, spacing: 8) {
                    Text("Artwork")
                        .font(.headline)

                    Toggle("Show artwork thumbnails in playlist rows", isOn: $viewConfig.showArtwork)

                    if viewConfig.showArtwork {
                        Picker("Artwork size", selection: $viewConfig.artworkSize) {
                            ForEach(PlaylistViewConfig.ArtworkSize.allCases) { size in
                                Text(size.rawValue).tag(size)
                            }
                        }
                        .pickerStyle(.segmented)
                        .frame(width: 250)
                    }
                }

                Divider()
            }
            .padding(24)
        }
    }
}

// MARK: - Playback Settings

private struct PlaybackSettings: View {
    @ObservedObject private var viewConfig = PlaylistViewConfig.shared

    var body: some View {
        VStack(alignment: .leading, spacing: 20) {
            Text("Cursor Behavior")
                .font(.title3.bold())

            VStack(alignment: .leading, spacing: 12) {
                Toggle("Cursor follows playback", isOn: Binding(
                    get: { viewConfig.cursorFollowsPlayback },
                    set: { newValue in
                        if newValue {
                            viewConfig.cursorFollowsPlayback = true
                            viewConfig.playbackFollowsCursor = false
                        } else {
                            viewConfig.cursorFollowsPlayback = false
                            viewConfig.playbackFollowsCursor = true
                        }
                    }
                ))
                Text("Auto-select and scroll to the currently playing track.")
                    .font(.callout)
                    .foregroundStyle(.secondary)
                    .padding(.leading, 20)

                Toggle("Playback follows cursor", isOn: Binding(
                    get: { viewConfig.playbackFollowsCursor },
                    set: { newValue in
                        if newValue {
                            viewConfig.playbackFollowsCursor = true
                            viewConfig.cursorFollowsPlayback = false
                        } else {
                            viewConfig.playbackFollowsCursor = false
                            viewConfig.cursorFollowsPlayback = true
                        }
                    }
                ))
                Text("When a track finishes, play the currently selected track next (foobar2000 behavior).")
                    .font(.callout)
                    .foregroundStyle(.secondary)
                    .padding(.leading, 20)
            }

            Spacer()
        }
        .padding(24)
    }
}

// MARK: - General Settings

private struct GeneralSettings: View {
    @AppStorage("autoAnalyzeOnImport") private var autoAnalyzeOnImport = true

    var body: some View {
        VStack(alignment: .leading, spacing: 20) {
            Text("General")
                .font(.title3.bold())

            VStack(alignment: .leading, spacing: 12) {
                Toggle("Auto-analyze BPM & Key on import", isOn: $autoAnalyzeOnImport)
                Text("Automatically detect BPM and musical key when adding tracks.")
                    .font(.callout)
                    .foregroundStyle(.secondary)
                    .padding(.leading, 20)
            }

            Spacer()
        }
        .padding(24)
    }
}

// MARK: - Keyboard Shortcut Settings

private struct KeyboardShortcutSettings: View {
    @ObservedObject private var config = KeyboardShortcutConfig.shared
    @State private var recordingAction: ShortcutAction?
    @State private var keyMonitor: Any?

    var body: some View {
        ScrollView {
            VStack(alignment: .leading, spacing: 20) {
                HStack {
                    Text("Keyboard Shortcuts")
                        .font(.title3.bold())
                    Spacer()
                    Button("Reset to Defaults") {
                        config.resetToDefaults()
                    }
                    .font(.caption)
                }

                Text("Click a shortcut to re-assign it. Press Escape to cancel.")
                    .font(.callout)
                    .foregroundStyle(.secondary)

                ForEach(ShortcutGroup.allCases, id: \.rawValue) { group in
                    VStack(alignment: .leading, spacing: 6) {
                        Text(group.rawValue)
                            .font(.headline)
                            .foregroundStyle(.secondary)

                        ForEach(group.actions) { action in
                            ShortcutRow(
                                action: action,
                                binding: config.binding(for: action),
                                isRecording: recordingAction == action,
                                onStartRecording: { startRecording(for: action) }
                            )
                        }
                    }

                    if group != .general {
                        Divider()
                    }
                }
            }
            .padding(24)
        }
        .onDisappear {
            stopRecording()
        }
    }

    private func startRecording(for action: ShortcutAction) {
        // Stop any existing recording
        stopRecording()
        recordingAction = action

        keyMonitor = NSEvent.addLocalMonitorForEvents(matching: .keyDown) { event in
            // Escape cancels
            if event.keyCode == 53 {
                self.stopRecording()
                return nil
            }
            let binding = ShortcutBinding.from(event)
            self.config.shortcuts[action] = binding
            self.stopRecording()
            return nil // consume the event
        }
    }

    private func stopRecording() {
        recordingAction = nil
        if let monitor = keyMonitor {
            NSEvent.removeMonitor(monitor)
            keyMonitor = nil
        }
    }
}

/// A single row: action name + clickable shortcut recorder button.
private struct ShortcutRow: View {
    let action: ShortcutAction
    let binding: ShortcutBinding
    let isRecording: Bool
    let onStartRecording: () -> Void

    var body: some View {
        HStack {
            Text(action.rawValue)
                .font(.system(size: 12))
                .frame(maxWidth: .infinity, alignment: .leading)

            Button {
                onStartRecording()
            } label: {
                Text(isRecording ? "Press shortcut…" : binding.displayString)
                    .font(.system(size: 12, design: isRecording ? .default : .monospaced))
                    .frame(minWidth: 90)
                    .padding(.horizontal, 8)
                    .padding(.vertical, 4)
                    .background(isRecording ? Color.accentColor.opacity(0.15) : Color.primary.opacity(0.05))
                    .clipShape(RoundedRectangle(cornerRadius: 6))
                    .overlay(
                        RoundedRectangle(cornerRadius: 6)
                            .stroke(isRecording ? Color.accentColor : Color.gray.opacity(0.3), lineWidth: 1)
                    )
            }
            .buttonStyle(.plain)
            .animation(.easeInOut(duration: 0.15), value: isRecording)
        }
        .padding(.vertical, 2)
    }
}

// MARK: - Chad Music Settings

private struct ChadMusicSettings: View {
    @AppStorage("chadMusic.serverURL") private var serverURL: String = ""
    @AppStorage("chadMusic.apiKey") private var apiKey: String = ""
    @State private var connectionStatus: ConnectionStatus = .unknown
    @State private var isTesting = false
    @State private var statsText: String = ""

    private enum ConnectionStatus {
        case unknown, testing, success, failed(String)
    }

    var body: some View {
        VStack(alignment: .leading, spacing: 20) {
            Text("Chad Music")
                .font(.title3.bold())

            Text("Connect to your Chad Music server to browse and stream your cloud library.")
                .font(.callout)
                .foregroundStyle(.secondary)

            // Server URL
            VStack(alignment: .leading, spacing: 6) {
                Text("Server URL")
                    .font(.headline)
                TextField("https://music.tailnet.ts.net", text: $serverURL)
                    .textFieldStyle(.roundedBorder)
                    .onChange(of: serverURL) { _, _ in
                        connectionStatus = .unknown
                    }
            }

            // API Key
            VStack(alignment: .leading, spacing: 6) {
                Text("API Key")
                    .font(.headline)
                SecureField("Enter API key", text: $apiKey)
                    .textFieldStyle(.roundedBorder)
                    .onChange(of: apiKey) { _, _ in
                        connectionStatus = .unknown
                    }
            }

            Divider()

            // Connection test
            HStack(spacing: 12) {
                Button("Test Connection") {
                    testConnection()
                }
                .disabled(serverURL.isEmpty || apiKey.isEmpty || isTesting)

                switch connectionStatus {
                case .unknown:
                    EmptyView()
                case .testing:
                    ProgressView()
                        .controlSize(.small)
                    Text("Connecting...")
                        .font(.callout)
                        .foregroundStyle(.secondary)
                case .success:
                    Image(systemName: "checkmark.circle.fill")
                        .foregroundStyle(.green)
                    Text(statsText)
                        .font(.callout)
                        .foregroundStyle(.secondary)
                case .failed(let message):
                    Image(systemName: "xmark.circle.fill")
                        .foregroundStyle(.red)
                    Text(message)
                        .font(.callout)
                        .foregroundStyle(.red)
                }
            }

            Spacer()
        }
        .padding(24)
    }

    private func testConnection() {
        connectionStatus = .testing
        isTesting = true
        Task {
            let client = ChadMusicAPIClient.shared
            let result = await client.testConnection()
            switch result {
            case .success(let stats):
                let parts = [
                    stats.tracks.map { "\($0) tracks" },
                    stats.albums.map { "\($0) albums" },
                    stats.artists.map { "\($0) artists" },
                ].compactMap { $0 }
                statsText = "Connected — " + parts.joined(separator: ", ")
                connectionStatus = .success
            case .failure(let error):
                connectionStatus = .failed(error.localizedDescription)
            }
            isTesting = false
        }
    }
}

// MARK: - Skin Preview Color

extension AppTheme.Skin {
    /// Approximate preview swatch color for the skin card.
    var previewColor: Color {
        switch self {
        case .dark:          return Color(red: 0.15, green: 0.15, blue: 0.17)
        case .midnight:      return Color(red: 0.1, green: 0.1, blue: 0.2)
        case .forest:        return Color(red: 0.1, green: 0.18, blue: 0.1)
        case .ocean:         return Color(red: 0.1, green: 0.15, blue: 0.2)
        case .warm:          return Color(red: 0.2, green: 0.15, blue: 0.1)
        case .light:         return Color(red: 0.95, green: 0.95, blue: 0.96)
        case .winampClassic: return Color(red: 0.12, green: 0.12, blue: 0.14)
        case .winampModern:  return Color(red: 0.13, green: 0.14, blue: 0.18)
        case .foobarDark:    return Color(red: 0.14, green: 0.14, blue: 0.14)
        case .foobarLight:   return Color(red: 0.94, green: 0.94, blue: 0.94)
        case .win95:         return Color(red: 0.75, green: 0.75, blue: 0.75)
        case .win98:         return Color(red: 0.83, green: 0.82, blue: 0.78)
        case .xpLuna:        return Color(red: 0.85, green: 0.89, blue: 0.95)
        case .macOSClassic:  return Color(red: 0.86, green: 0.86, blue: 0.86)
        }
    }
}