import 'package:cached_network_image/cached_network_image.dart';
import 'package:flutter/material.dart';

import '/features/core/data/constants/const_colors.dart';
import '/features/core/data/constants/const_durations.dart';
import '/features/core/data/constants/const_media.dart';
import '/features/core/widgets/gap.dart';
import '/features/core/widgets/mcg_scaffold.dart';
import '/features/core/widgets/state/multi_value_listenable_builder.dart';
import '/features/core/widgets/state/view_model_builder.dart';
import '/features/home/widgets/custom_wrap.dart';
import '../../data/enums/search_option.dart';
import '../../data/models/image_model.dart';
import 'gallery_view_model.dart';

part 'downloaded_gallery_view.dart';
part 'search_gallery_view.dart';

class GalleryView extends StatelessWidget {
  const GalleryView({super.key});

  @override
  Widget build(BuildContext context) {
    return ViewModelBuilder<GalleryViewModel>(
      viewModelBuilder: () => GalleryViewModel.locate,
      builder: (context, final model) => McgScaffold(
        bodyBuilderWaiter: model.isInitialised,
        forceInternetCheck: true,
        appBar: AppBar(
          centerTitle: true,
          primary: true,
          title: ValueListenableBuilder<bool>(
            valueListenable: model.isSearchingListenable,
            builder: (context, final isSearching, _) => AnimatedSwitcher(
              duration: ConstDurations.quarterDefaultAnimationDuration,
              child: !isSearching
                  ? Center(child: Text(model.strings.gallery))
                  : _SearchBox(galleryViewModel: model),
            ),
          ),
          actions: [
            Padding(
              padding: const EdgeInsets.only(right: 40),
              child: MultiValueListenableBuilder(
                valueListenables: [
                  model.isDisplayingPressingPrompt,
                  model.isSearchingListenable,
                ],
                builder: (context, final values, child) => !model.isDisplayingPressingPrompt.value
                    ? IconButton(
                        isSelected: model.isSearchingListenable.value,
                        icon: const Icon(Icons.search),
                        selectedIcon: const Icon(Icons.close),
                        onPressed: model.searchPressed,
                      )
                    : const SizedBox.shrink(),
              ),
            )
          ],
        ),
        body: Center(
          child: ValueListenableBuilder<bool>(
            valueListenable: model.isDisplayingPressingPrompt,
            builder: (context, final isDisplayingPressingPrompt, _) => AnimatedSwitcher(
              duration: ConstDurations.defaultAnimationDuration,
              child: isDisplayingPressingPrompt
                  ? ElevatedButton(
                      onPressed: model.onPromptPressed,
                      child: Text(model.strings.startLoadingPrompt),
                    )
                  : SingleChildScrollView(
                      child: FutureBuilder<void>(
                        future: model.initImageFetchIsDone,
                        builder: (context, final snapshot) {
                          switch (snapshot.connectionState) {
                            case ConnectionState.none:
                            case ConnectionState.waiting:
                            case ConnectionState.active:
                              return const CircularProgressIndicator();
                            case ConnectionState.done:
                              return ValueListenableBuilder<bool>(
                                valueListenable: model.isSearchingListenable,
                                builder: (context, final isSearching, _) => AnimatedSwitcher(
                                  duration: ConstDurations.oneAndHalfDefaultAnimationDuration,
                                  child: !isSearching
                                      ? Column(
                                          mainAxisAlignment: MainAxisAlignment.spaceEvenly,
                                          children: [
                                            ValueListenableBuilder<bool>(
                                              valueListenable: model.isViewingFavouriteListenable,
                                              builder:
                                                  (context, final isViewingFavourites, child) =>
                                                      Row(
                                                mainAxisAlignment: MainAxisAlignment.center,
                                                children: [
                                                  ConstMedia.buildIcon(
                                                    ConstMedia.favStarOutline,
                                                    width: 24,
                                                    height: 24,
                                                  ),
                                                  Switch(
                                                    value: isViewingFavourites,
                                                    onChanged: model.onFavouriteViewChange,
                                                  ),
                                                  ConstMedia.buildIcon(
                                                    ConstMedia.favStarFilled,
                                                    width: 24,
                                                    height: 24,
                                                  ),
                                                ],
                                              ),
                                            ),
                                            _DownloadedGalleryView(galleryViewModel: model),
                                          ],
                                        )
                                      : _SearchGalleryView(galleryViewModel: model),
                                ),
                              );
                          }
                        },
                      ),
                    ),
            ),
          ),
        ),
      ),
    );
  }
}

class _SearchBox extends StatelessWidget {
  const _SearchBox({
    required this.galleryViewModel,
    super.key,
  });

  final GalleryViewModel galleryViewModel;

  @override
  Widget build(BuildContext context) {
    return Row(
      children: [
        ValueListenableBuilder<SearchOption>(
          valueListenable: galleryViewModel.searchOptionListenable,
          builder: (context, final searchOption, _) => Padding(
            padding: const EdgeInsets.only(top: 8),
            child: DropdownButton<SearchOption>(
              underline: const SizedBox.shrink(),
              borderRadius: BorderRadius.circular(24),
              items: [
                for (final searchOption in SearchOption.values)
                  DropdownMenuItem(
                    value: searchOption,
                    child: Center(child: Text(searchOption.name)),
                  ),
              ],
              value: searchOption,
              onChanged: galleryViewModel.onSearchOptionChanged,
            ),
          ),
        ),
        const Gap(18),
        Expanded(
          child: TextField(
            autofocus: true,
            decoration: InputDecoration(
              hintText: galleryViewModel.strings.searchForImage,
            ),
            onChanged: galleryViewModel.onSearchTermUpdate,
          ),
        ),
      ],
    );
  }
}