part of '../collection_browser.dart';

class _ContentList extends StatelessWidget {
  const _ContentList();

  @override
  Widget build(BuildContext context) {
    return _BlocBuilder(
      buildWhen: (previous, current) => previous.zoom != current.zoom,
      builder: (context, state) => _ContentListBody(
        maxCrossAxisExtent: photo_list_util.getThumbSize(state.zoom).toDouble(),
      ),
    );
  }
}

class _ScalingList extends StatelessWidget {
  const _ScalingList();

  @override
  Widget build(BuildContext context) {
    return _BlocBuilder(
      buildWhen: (previous, current) => previous.scale != current.scale,
      builder: (context, state) {
        if (state.scale == null) {
          return const SizedBox.shrink();
        }
        int nextZoom;
        if (state.scale! > 1) {
          nextZoom = state.zoom + 1;
        } else {
          nextZoom = state.zoom - 1;
        }
        nextZoom = nextZoom.clamp(-1, 2);
        return _ContentListBody(
          maxCrossAxisExtent: photo_list_util.getThumbSize(nextZoom).toDouble(),
        );
      },
    );
  }
}

class _ContentListBody extends StatelessWidget {
  const _ContentListBody({
    required this.maxCrossAxisExtent,
  });

  @override
  Widget build(BuildContext context) {
    return _BlocBuilder(
      buildWhen: (previous, current) =>
          previous.collection != current.collection ||
          previous.transformedItems != current.transformedItems ||
          previous.selectedItems != current.selectedItems,
      builder: (context, state) => SelectableItemList<_Item>(
        maxCrossAxisExtent: maxCrossAxisExtent,
        items: state.transformedItems,
        itemBuilder: (context, _, item) => item.buildWidget(context),
        staggeredTileBuilder: (_, item) => item.staggeredTile,
        selectedItems: state.selectedItems,
        onSelectionChange: (_, selected) {
          context.addEvent(_SetSelectedItems(items: selected.cast()));
        },
        onItemTap: (context, index, _) {
          if (state.transformedItems[index] is! _FileItem) {
            return;
          }
          final actualIndex = index -
              state.transformedItems
                  .sublist(0, index)
                  .where((e) => e is! _FileItem)
                  .length;
          Navigator.of(context).pushNamed(
            Viewer.routeName,
            arguments: ViewerArguments(
              context.bloc.account,
              state.transformedItems
                  .whereType<_FileItem>()
                  .map((e) => e.file)
                  .toList(),
              actualIndex,
              fromCollection: ViewerCollectionData(
                state.collection,
                state.transformedItems
                    .whereType<_ActualItem>()
                    .map((e) => e.original)
                    .toList(),
              ),
            ),
          );
        },
      ),
    );
  }

  final double maxCrossAxisExtent;
}

class _EditContentList extends StatelessWidget {
  const _EditContentList();

  @override
  Widget build(BuildContext context) {
    return StreamBuilder<int>(
      stream: context.read<PrefController>().albumBrowserZoomLevel,
      initialData: context.read<PrefController>().albumBrowserZoomLevel.value,
      builder: (_, zoomLevel) {
        if (zoomLevel.hasError) {
          context.addEvent(
              _SetMessage(L10n.global().writePreferenceFailureNotification));
        }
        return _BlocBuilder(
          buildWhen: (previous, current) =>
              previous.editTransformedItems != current.editTransformedItems,
          builder: (context, state) {
            if (context.bloc.isCollectionCapabilityPermitted(
                CollectionCapability.manualSort)) {
              return DraggableItemList<_Item>(
                maxCrossAxisExtent: photo_list_util
                    .getThumbSize(zoomLevel.requireData)
                    .toDouble(),
                items: state.editTransformedItems ?? state.transformedItems,
                itemBuilder: (context, _, item) => item.buildWidget(context),
                itemDragFeedbackBuilder: (context, _, item) =>
                    item.buildDragFeedbackWidget(context),
                staggeredTileBuilder: (_, item) => item.staggeredTile,
                onDragResult: (results) {
                  context.addEvent(_EditManualSort(results));
                },
                onDraggingChanged: (value) {
                  context.addEvent(_SetDragging(value));
                },
              );
            } else {
              return SelectableItemList<_Item>(
                maxCrossAxisExtent: photo_list_util
                    .getThumbSize(zoomLevel.requireData)
                    .toDouble(),
                items: state.editTransformedItems ?? state.transformedItems,
                itemBuilder: (context, _, item) => item.buildWidget(context),
                staggeredTileBuilder: (_, item) => item.staggeredTile,
              );
            }
          },
        );
      },
    );
  }
}

/// Unmodifiable content list under edit mode
class _UnmodifiableEditContentList extends StatelessWidget {
  const _UnmodifiableEditContentList();

  @override
  Widget build(BuildContext context) {
    return SliverIgnorePointer(
      ignoring: true,
      sliver: SliverOpacity(
        opacity: .25,
        sliver: StreamBuilder<int>(
          stream: context.read<PrefController>().albumBrowserZoomLevel,
          initialData:
              context.read<PrefController>().albumBrowserZoomLevel.value,
          builder: (_, zoomLevel) {
            if (zoomLevel.hasError) {
              context.addEvent(_SetMessage(
                  L10n.global().writePreferenceFailureNotification));
            }
            return _BlocBuilder(
              buildWhen: (previous, current) =>
                  previous.editTransformedItems != current.editTransformedItems,
              builder: (context, state) {
                return SelectableItemList<_Item>(
                  maxCrossAxisExtent: photo_list_util
                      .getThumbSize(zoomLevel.requireData)
                      .toDouble(),
                  items: state.editTransformedItems ?? state.transformedItems,
                  itemBuilder: (context, _, item) => item.buildWidget(context),
                  staggeredTileBuilder: (_, item) => item.staggeredTile,
                );
              },
            );
          },
        ),
      ),
    );
  }
}