import SwiftUI

struct DocumentsView: View {
    @ObservedObject private var model = DocumentsModel.shared

    var body: some View {
        ScrollView(.vertical, showsIndicators: false) {
            if model.directoryContents.isEmpty {
                NoDocumentsView()
            } else {
                ForEach(model.sortedDirectoryContents, id: \.absoluteString) { url in
                    let video = Video.local(model.standardizedURL(url) ?? url)
                    PlayerQueueRow(
                        item: PlayerQueueItem(video)
                    )
                    .contextMenu {
                        VideoContextMenuView(video: video)
                    }
                }
                .id(model.refreshID)
                .transition(.opacity)
            }
            Color.clear.padding(.bottom, 50)
        }
        .onAppear {
            if model.directoryURL.isNil {
                model.goToTop()
            }
        }
        .toolbar {
            ToolbarItem(placement: .navigationBarLeading) {
                if model.canGoBack {
                    Button {
                        withAnimation {
                            model.goBack()
                        }
                    } label: {
                        HStack(spacing: 6) {
                            Label("Go back", systemImage: "chevron.left")
                        }
                    }
                    .transaction { t in t.animation = .none }
                    .disabled(!model.canGoBack)
                }
            }
        }
        .navigationTitle(model.directoryLabel)
        .padding(.horizontal)
        .navigationBarTitleDisplayMode(RefreshControl.navigationBarTitleDisplayMode)
        .backport
        .refreshable {
            DispatchQueue.main.async {
                self.refresh()
            }
        }
    }

    func refresh() {
        withAnimation {
            model.refresh()
        }
    }
}

struct DocumentsView_Previews: PreviewProvider {
    static var previews: some View {
        NavigationView {
            DocumentsView()
        }
        .injectFixtureEnvironmentObjects()
        .navigationViewStyle(.stack)
    }
}