//
// Swiftfin is subject to the terms of the Mozilla Public
// License, v2.0. If a copy of the MPL was not distributed with this
// file, you can obtain one at https://mozilla.org/MPL/2.0/.
//
// Copyright (c) 2022 Jellyfin & Jellyfin Contributors
//

import JellyfinAPI
import SwiftUI

struct EpisodesRowView<RowManager>: View where RowManager: EpisodesRowManager {

    @EnvironmentObject
    var itemRouter: ItemCoordinator.Router
    @ObservedObject
    var viewModel: RowManager
    let onlyCurrentSeason: Bool

    var body: some View {
        VStack(alignment: .leading) {

            Text(viewModel.selectedSeason?.name ?? L10n.episodes)
                .font(.title3)
                .padding(.horizontal, 50)

            ScrollView(.horizontal) {
                ScrollViewReader { reader in
                    HStack(alignment: .top) {
                        if viewModel.isLoading {
                            VStack(alignment: .leading) {

                                ZStack {
                                    Color.secondary.ignoresSafeArea()

                                    ProgressView()
                                }
                                .mask(Rectangle().frame(width: 500, height: 280))
                                .frame(width: 500, height: 280)

                                VStack(alignment: .leading) {
                                    Text("S-E-")
                                        .font(.caption)
                                        .foregroundColor(.secondary)
                                    Text("--")
                                        .font(.footnote)
                                        .padding(.bottom, 1)
                                    Text("--")
                                        .font(.caption)
                                        .fontWeight(.light)
                                        .lineLimit(4)
                                }
                                .padding(.horizontal)

                                Spacer()
                            }
                            .frame(width: 500)
                            .focusable()
                        } else if let selectedSeason = viewModel.selectedSeason {
                            if let seasonEpisodes = viewModel.seasonsEpisodes[selectedSeason] {
                                if seasonEpisodes.isEmpty {
                                    VStack(alignment: .leading) {

                                        Color.secondary
                                            .mask(Rectangle().frame(width: 500, height: 280))
                                            .frame(width: 500, height: 280)

                                        VStack(alignment: .leading) {
                                            Text("--")
                                                .font(.caption)
                                                .foregroundColor(.secondary)
                                            L10n.noEpisodesAvailable.text
                                                .font(.footnote)
                                                .padding(.bottom, 1)
                                        }
                                        .padding(.horizontal)

                                        Spacer()
                                    }
                                    .frame(width: 500)
                                    .focusable()
                                } else {
                                    ForEach(viewModel.seasonsEpisodes[selectedSeason]!, id: \.self) { episode in
                                        EpisodeRowCard(viewModel: viewModel, episode: episode)
                                            .id(episode.id)
                                    }
                                }
                            }
                        }
                    }
                    .padding(.horizontal, 50)
                    .padding(.vertical)
                    .onChange(of: viewModel.selectedSeason) { _ in
                        if viewModel.selectedSeason?.id == viewModel.item.seasonId {
                            reader.scrollTo(viewModel.item.id)
                        }
                    }
                    .onChange(of: viewModel.seasonsEpisodes) { _ in
                        if viewModel.selectedSeason?.id == viewModel.item.seasonId {
                            reader.scrollTo(viewModel.item.id)
                        }
                    }
                }
                .edgesIgnoringSafeArea(.horizontal)
            }
        }
    }
}