import SwiftUI

/// The library's card presentation of `viewModel.bookmarks`. Drops into
/// BookmarksView's content area in place of the List and carries the same
/// actions — tap to open, long press for the full menu. The filter strip above
/// it belongs to BookmarksView, since both layouts share it.
struct LibraryGridView: View {
    @Bindable var viewModel: BookmarksViewModel
    let onOpen: (Bookmark) -> Void
    let onEdit: (Bookmark) -> Void

    @Environment(\.openURL) private var openURL
    @State private var showFullPlayer = false
    @State private var episodePicker: Bookmark?

    private var items: [LibraryItem] {
        viewModel.bookmarks.map(LibraryItem.init(bookmark:))
    }

    var body: some View {
        ScrollView {
            LazyVGrid(
                // Two columns, not three: at the scaled-up type a third
                // column leaves ~9 characters per line and every title
                // truncates. The text size sets the column count.
                columns: Array(repeating: GridItem(.flexible(), spacing: 10), count: 2),
                spacing: 10
            ) {
                ForEach(items) { item in
                    card(item)
                }
            }
            .padding(.horizontal, 18)
            .padding(.top, 16)
            .padding(.bottom, 40)

            if viewModel.isLoadingMore {
                ProgressView().padding(.bottom, 28)
            }
        }
        .scrollBounceBehavior(.basedOnSize)
        .background(Paper.sheet)
        .podcastSheets(
            viewModel: viewModel,
            showFullPlayer: $showFullPlayer,
            episodePicker: $episodePicker
        )
    }

    @ViewBuilder
    private func card(_ item: LibraryItem) -> some View {
        // The grid renders LibraryItems, but every action needs the Bookmark it
        // came from. Ids are linkding's, so this is a direct lookup.
        if let bookmark = viewModel.bookmarks.first(where: { $0.id == item.id }) {
            Button { onOpen(bookmark) } label: {
                LibraryCard(item: item)
            }
            .buttonStyle(RowPressStyle())
            .contextMenu {
                bookmarkMenuItems(
                    bookmark: bookmark,
                    viewModel: viewModel,
                    openURL: openURL,
                    onOpen: { onOpen(bookmark) },
                    onEdit: { onEdit(bookmark) },
                    onPodcast: {
                        launchPodcast(
                            for: bookmark,
                            viewModel: viewModel,
                            showFullPlayer: $showFullPlayer,
                            episodePicker: $episodePicker
                        )
                    }
                )
            }
            .onAppear { maybeLoadMore(bookmark) }
        }
    }

    private func maybeLoadMore(_ bookmark: Bookmark) {
        guard let last = viewModel.bookmarks.last, last.id == bookmark.id,
              viewModel.nextPageUrl != nil, !viewModel.isLoadingMore else { return }
        Task { await viewModel.loadMore() }
    }
}