import AVKit
import SwiftUI

struct FeedView: View {
    @Environment(GamesViewModel.self) private var gamesViewModel
    @State private var viewModel = FeedViewModel()
    @State private var playingURL: URL?

    var body: some View {
        ScrollView {
            VStack(alignment: .leading, spacing: DS.Spacing.sectionGap) {
                // Header
                HStack {
                    VStack(alignment: .leading, spacing: 4) {
                        Text("HIGHLIGHTS")
                            .font(DS.Fonts.caption)
                            .foregroundStyle(DS.Colors.textQuaternary)
                            .kerning(3)
                        Text("Across the League")
                            #if os(tvOS)
                            .font(DS.Fonts.tvSectionTitle)
                            #else
                            .font(DS.Fonts.sectionTitle)
                            #endif
                            .foregroundStyle(DS.Colors.textPrimary)
                    }

                    Spacer()

                    if viewModel.isLoading {
                        ProgressView()
                    }
                }

                if viewModel.highlights.isEmpty && !viewModel.isLoading {
                    emptyState
                } else {
                    LazyVStack(spacing: DS.Spacing.cardGap) {
                        ForEach(viewModel.highlights) { item in
                            highlightCard(item)
                        }
                    }
                }
            }
            .padding(.horizontal, edgeInset)
            .padding(.vertical, DS.Spacing.sectionGap)
        }
        .task {
            await viewModel.loadHighlights(games: gamesViewModel.games)
        }
        .onChange(of: gamesViewModel.games.count) {
            Task { await viewModel.loadHighlights(games: gamesViewModel.games) }
        }
        .onAppear { viewModel.startAutoRefresh(games: gamesViewModel.games) }
        .onDisappear { viewModel.stopAutoRefresh() }
        .fullScreenCover(isPresented: Binding(
            get: { playingURL != nil },
            set: { if !$0 { playingURL = nil } }
        )) {
            if let url = playingURL {
                let player = AVPlayer(url: url)
                VideoPlayer(player: player)
                    .ignoresSafeArea()
                    .onAppear { player.play() }
                    .onDisappear { player.pause() }
            }
        }
    }

    @ViewBuilder
    private func highlightCard(_ item: HighlightItem) -> some View {
        Button {
            playingURL = item.hlsURL ?? item.mp4URL
        } label: {
            HStack(spacing: 16) {
                // Thumbnail
                ZStack {
                    HStack(spacing: 0) {
                        Rectangle().fill(TeamAssets.color(for: item.awayCode).opacity(0.3))
                        Rectangle().fill(TeamAssets.color(for: item.homeCode).opacity(0.3))
                    }

                    HStack(spacing: thumbnailLogoGap) {
                        TeamLogoView(
                            team: TeamInfo(code: item.awayCode, name: "", score: nil),
                            size: thumbnailLogoSize
                        )
                        Text("@")
                            .font(.system(size: atFontSize, weight: .bold))
                            .foregroundStyle(DS.Colors.textTertiary)
                        TeamLogoView(
                            team: TeamInfo(code: item.homeCode, name: "", score: nil),
                            size: thumbnailLogoSize
                        )
                    }

                    Image(systemName: "play.circle.fill")
                        .font(.system(size: playIconSize))
                        .foregroundStyle(.white.opacity(0.7))
                        .shadow(radius: 4)

                    if item.isCondensedGame {
                        VStack {
                            HStack {
                                Spacer()
                                Text("CONDENSED")
                                    .font(badgeFont)
                                    .foregroundStyle(.white)
                                    .kerning(0.5)
                                    .padding(.horizontal, 8)
                                    .padding(.vertical, 4)
                                    .background(DS.Colors.media)
                                    .clipShape(Capsule())
                            }
                            Spacer()
                        }
                        .padding(8)
                    }
                }
                .frame(width: thumbnailWidth, height: thumbnailHeight)
                .clipShape(RoundedRectangle(cornerRadius: DS.Radii.compact))

                // Info
                VStack(alignment: .leading, spacing: 6) {
                    HStack {
                        Text(item.gameTitle)
                            .font(gameTagFont)
                            .foregroundStyle(DS.Colors.textTertiary)
                            .kerning(0.8)

                        Spacer()

                        Text(timeAgo(item.timestamp))
                            .font(gameTagFont)
                            .foregroundStyle(DS.Colors.textQuaternary)
                    }

                    Text(item.headline)
                        .font(headlineFont)
                        .foregroundStyle(DS.Colors.textPrimary)
                        .lineLimit(2)
                }

                Spacer(minLength: 0)
            }
            .padding(DS.Spacing.panelPadCompact)
            .background(DS.Colors.panelFill)
            .clipShape(RoundedRectangle(cornerRadius: DS.Radii.standard))
            .overlay(
                RoundedRectangle(cornerRadius: DS.Radii.standard)
                    .strokeBorder(DS.Colors.panelStroke, lineWidth: 0.5)
            )
        }
        .platformCardStyle()
    }

    private var emptyState: some View {
        VStack(spacing: 16) {
            Image(systemName: "play.rectangle.on.rectangle")
                .font(.system(size: 44))
                .foregroundStyle(DS.Colors.textQuaternary)
            Text("No highlights available yet")
                .font(DS.Fonts.body)
                .foregroundStyle(DS.Colors.textTertiary)
            Text("Highlights appear as games are played")
                .font(DS.Fonts.bodySmall)
                .foregroundStyle(DS.Colors.textQuaternary)
        }
        .frame(maxWidth: .infinity)
        .padding(.top, 80)
    }

    // MARK: - Platform sizing

    private func timeAgo(_ date: Date) -> String {
        let interval = Date().timeIntervalSince(date)
        if interval < 60 { return "Just now" }
        if interval < 3600 { return "\(Int(interval / 60))m ago" }
        if interval < 86400 { return "\(Int(interval / 3600))h ago" }
        return "\(Int(interval / 86400))d ago"
    }

    #if os(tvOS)
    private var edgeInset: CGFloat { 60 }
    private var thumbnailWidth: CGFloat { 300 }
    private var thumbnailHeight: CGFloat { 160 }
    private var thumbnailLogoSize: CGFloat { 48 }
    private var thumbnailLogoGap: CGFloat { 20 }
    private var playIconSize: CGFloat { 40 }
    private var atFontSize: CGFloat { 22 }
    private var headlineFont: Font { .system(size: 24, weight: .semibold) }
    private var gameTagFont: Font { .system(size: 22, weight: .bold, design: .rounded) }
    private var badgeFont: Font { .system(size: 18, weight: .bold, design: .rounded) }
    #else
    private var edgeInset: CGFloat { 20 }
    private var thumbnailWidth: CGFloat { 180 }
    private var thumbnailHeight: CGFloat { 100 }
    private var thumbnailLogoSize: CGFloat { 32 }
    private var thumbnailLogoGap: CGFloat { 12 }
    private var playIconSize: CGFloat { 28 }
    private var atFontSize: CGFloat { 14 }
    private var headlineFont: Font { .system(size: 15, weight: .semibold) }
    private var gameTagFont: Font { .system(size: 12, weight: .bold, design: .rounded) }
    private var badgeFont: Font { .system(size: 11, weight: .bold, design: .rounded) }
    #endif
}