import 'dart:math' as math;

import 'package:easy_localization/easy_localization.dart';
import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
import 'package:gap/gap.dart';
import 'package:hooks_riverpod/hooks_riverpod.dart';
import 'package:island/models/sticker.dart';
import 'package:island/pods/network.dart';
import 'package:island/widgets/content/cloud_files.dart';
import 'package:material_symbols_icons/symbols.dart';
import 'package:riverpod_annotation/riverpod_annotation.dart';
import 'package:styled_widget/styled_widget.dart';
import 'package:flutter_popup_card/flutter_popup_card.dart';

part 'picker.g.dart';

/// Fetch user-added sticker packs (with stickers) from API:
/// GET /sphere/stickers/me
@riverpod
Future<List<SnStickerPack>> myStickerPacks(Ref ref) async {
  final api = ref.watch(apiClientProvider);
  final resp = await api.get('/sphere/stickers/me');
  final data = resp.data;
  if (data is List) {
    return data
        .map((e) => SnStickerPack.fromJson(e as Map<String, dynamic>))
        .toList();
  }
  return const <SnStickerPack>[];
}

/// Sticker Picker popover dialog
/// - Displays user-owned sticker packs as tabs (chips)
/// - Shows grid of stickers in selected pack
/// - On tap, returns placeholder string :{prefix}{slug}: via onPick callback
class StickerPicker extends HookConsumerWidget {
  final void Function(String placeholder) onPick;

  const StickerPicker({super.key, required this.onPick});

  @override
  Widget build(BuildContext context, WidgetRef ref) {
    final packsAsync = ref.watch(myStickerPacksProvider);

    return PopupCard(
      elevation: 8,
      shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(12.0)),
      child: ConstrainedBox(
        constraints: const BoxConstraints(maxWidth: 520, maxHeight: 520),
        child: packsAsync.when(
          data: (packs) {
            if (packs.isEmpty) {
              return _EmptyState(
                onRefresh: () async {
                  ref.invalidate(myStickerPacksProvider);
                },
              );
            }

            // Maintain selected index locally with a ValueNotifier to avoid hooks dependency
            return _PackSwitcher(
              packs: packs,
              onPick: (pack, sticker) {
                final placeholder = ':${pack.prefix}${sticker.slug}:';
                HapticFeedback.selectionClick();
                onPick(placeholder);
                if (Navigator.of(context).canPop()) {
                  Navigator.of(context).pop();
                }
              },
              onRefresh: () async {
                ref.invalidate(myStickerPacksProvider);
              },
            );
          },
          loading:
              () => const SizedBox(
                width: 320,
                height: 320,
                child: Center(child: CircularProgressIndicator()),
              ),
          error:
              (err, _) => SizedBox(
                width: 360,
                height: 200,
                child: Column(
                  mainAxisAlignment: MainAxisAlignment.center,
                  children: [
                    const Icon(Symbols.error, size: 28),
                    const Gap(8),
                    Text('Error: $err', textAlign: TextAlign.center),
                    const Gap(12),
                    FilledButton.icon(
                      onPressed: () => ref.invalidate(myStickerPacksProvider),
                      icon: const Icon(Symbols.refresh),
                      label: Text('retry').tr(),
                    ),
                  ],
                ).padding(all: 16),
              ),
        ),
      ),
    );
  }
}

class _EmptyState extends StatelessWidget {
  final Future<void> Function() onRefresh;
  const _EmptyState({required this.onRefresh});

  @override
  Widget build(BuildContext context) {
    return SizedBox(
      width: 360,
      height: 220,
      child: Column(
        mainAxisAlignment: MainAxisAlignment.center,
        children: [
          const Icon(Symbols.emoji_symbols, size: 28),
          const Gap(8),
          Text('noStickerPacks'.tr(), textAlign: TextAlign.center),
          const Gap(12),
          OutlinedButton.icon(
            onPressed: onRefresh,
            icon: const Icon(Symbols.refresh),
            label: Text('refresh').tr(),
          ),
        ],
      ).padding(all: 16),
    );
  }
}

class _PackSwitcher extends StatefulWidget {
  final List<SnStickerPack> packs;
  final void Function(SnStickerPack pack, SnSticker sticker) onPick;
  final Future<void> Function() onRefresh;

  const _PackSwitcher({
    required this.packs,
    required this.onPick,
    required this.onRefresh,
  });

  @override
  State<_PackSwitcher> createState() => _PackSwitcherState();
}

class _PackSwitcherState extends State<_PackSwitcher> {
  int _index = 0;

  @override
  Widget build(BuildContext context) {
    final packs = widget.packs;
    _index = _index.clamp(0, packs.length - 1);

    final selectedPack = packs[_index];

    return Column(
      crossAxisAlignment: CrossAxisAlignment.stretch,
      children: [
        // Header
        Row(
          children: [
            const Icon(Symbols.sticky_note_2, size: 20),
            const Gap(8),
            Text(
              'stickers'.tr(),
              style: Theme.of(context).textTheme.titleMedium,
            ),
            const Spacer(),
            IconButton(
              padding: EdgeInsets.zero,
              visualDensity: VisualDensity.compact,
              tooltip: 'close'.tr(),
              onPressed: () => Navigator.of(context).maybePop(),
              icon: const Icon(Symbols.close),
            ),
          ],
        ).padding(horizontal: 12, top: 8),

        // Vertical, scrollable packs rail like common emoji pickers
        SizedBox(
          height: 48,
          child: ListView.separated(
            padding: const EdgeInsets.symmetric(horizontal: 8),
            scrollDirection: Axis.horizontal,
            itemCount: packs.length,
            separatorBuilder: (_, _) => const Gap(4),
            itemBuilder: (context, i) {
              final selected = _index == i;
              return Tooltip(
                message: packs[i].name,
                child: FilterChip(
                  label: Text(packs[i].name, overflow: TextOverflow.ellipsis),
                  selected: selected,
                  onSelected: (_) {
                    setState(() => _index = i);
                    HapticFeedback.selectionClick();
                  },
                ),
              );
            },
          ),
        ).padding(bottom: 8),
        const Divider(height: 1),

        // Content
        Expanded(
          child: RefreshIndicator(
            onRefresh: widget.onRefresh,
            child: _StickersGrid(
              pack: selectedPack,
              onPick: (sticker) => widget.onPick(selectedPack, sticker),
            ),
          ),
        ),
      ],
    );
  }
}

class _StickersGrid extends StatelessWidget {
  final SnStickerPack pack;
  final void Function(SnSticker sticker) onPick;

  const _StickersGrid({required this.pack, required this.onPick});

  @override
  Widget build(BuildContext context) {
    final stickers = pack.stickers;

    if (stickers.isEmpty) {
      return Center(child: Text('noStickersInPack'.tr()));
    }

    return GridView.builder(
      physics: const AlwaysScrollableScrollPhysics(),
      padding: const EdgeInsets.symmetric(horizontal: 12, vertical: 12),
      gridDelegate: const SliverGridDelegateWithMaxCrossAxisExtent(
        maxCrossAxisExtent: 96,
        mainAxisSpacing: 12,
        crossAxisSpacing: 12,
      ),
      itemCount: stickers.length,
      itemBuilder: (context, index) {
        final sticker = stickers[index];
        final placeholder = ':${pack.prefix}${sticker.slug}:';
        return Tooltip(
          message: placeholder,
          child: InkWell(
            borderRadius: const BorderRadius.all(Radius.circular(8)),
            onTap: () => onPick(sticker),
            child: ClipRRect(
              borderRadius: const BorderRadius.all(Radius.circular(8)),
              child: DecoratedBox(
                decoration: BoxDecoration(
                  color: Theme.of(context).colorScheme.surfaceContainer,
                  borderRadius: const BorderRadius.all(Radius.circular(8)),
                ),
                child: AspectRatio(
                  aspectRatio: 1,
                  child: CloudImageWidget(
                    fileId: sticker.imageId,
                    fit: BoxFit.contain,
                  ),
                ),
              ),
            ),
          ),
        );
      },
    );
  }
}

/// Helper to show sticker picker as an anchored popover near the trigger.
/// Provide the button's BuildContext (typically from the onPressed closure).
/// Fallbacks to dialog if overlay cannot be found (e.g., during tests).
Future<void> showStickerPickerPopover(
  BuildContext context,
  Offset offset, {
  required void Function(String placeholder) onPick,
}) async {
  // Use flutter_popup_card to present the anchored popup near trigger.
  await showPopupCard<void>(
    context: context,
    offset: offset,
    alignment: Alignment.topLeft,
    dimBackground: true,
    builder:
        (ctx) => SizedBox(
          width: math.min(480, MediaQuery.of(context).size.width * 0.9),
          height: 480,
          child: ProviderScope(
            parent: ProviderScope.containerOf(context),
            child: StickerPicker(
              onPick: (ph) {
                onPick(ph);
                Navigator.of(ctx).maybePop();
              },
            ),
          ),
        ),
  );
}