import 'package:auto_route/auto_route.dart';
import 'package:dio/dio.dart';
import 'package:easy_localization/easy_localization.dart';
import 'package:flutter/material.dart';
import 'package:flutter_hooks/flutter_hooks.dart';
import 'package:freezed_annotation/freezed_annotation.dart';
import 'package:gap/gap.dart';
import 'package:hooks_riverpod/hooks_riverpod.dart';
import 'package:island/models/chat.dart';
import 'package:island/pods/network.dart';
import 'package:island/route.gr.dart';
import 'package:island/screens/chat/chat.dart';
import 'package:island/widgets/account/account_picker.dart';
import 'package:island/widgets/alert.dart';
import 'package:island/widgets/app_scaffold.dart';
import 'package:island/widgets/content/cloud_files.dart';
import 'package:material_symbols_icons/symbols.dart';
import 'package:modal_bottom_sheet/modal_bottom_sheet.dart';
import 'package:styled_widget/styled_widget.dart';

part 'room_detail.freezed.dart';

@RoutePage()
class ChatDetailScreen extends HookConsumerWidget {
  final int id;
  const ChatDetailScreen({super.key, @PathParam("id") required this.id});

  @override
  Widget build(BuildContext context, WidgetRef ref) {
    final roomState = ref.watch(chatroomProvider(id));
    final roomIdentity = ref.watch(chatroomIdentityProvider(id));

    final isModerator = roomIdentity.when(
      loading: () => false,
      error: (error, _) => false,
      data: (identity) => (identity?.role ?? 0) >= 50,
    );

    const iconShadow = Shadow(
      color: Colors.black54,
      blurRadius: 5.0,
      offset: Offset(1.0, 1.0),
    );

    return Scaffold(
      body: roomState.when(
        loading: () => const Center(child: CircularProgressIndicator()),
        error: (error, _) => Center(child: Text('Error: $error')),
        data:
            (currentRoom) => CustomScrollView(
              slivers: [
                SliverAppBar(
                  expandedHeight: 180,
                  pinned: true,
                  leading: PageBackButton(shadows: [iconShadow]),
                  flexibleSpace: FlexibleSpaceBar(
                    background:
                        currentRoom?.backgroundId != null
                            ? CloudImageWidget(
                              fileId: currentRoom!.backgroundId!,
                              fit: BoxFit.cover,
                            )
                            : Container(
                              color:
                                  Theme.of(context).appBarTheme.backgroundColor,
                            ),
                    title: Text(
                      currentRoom?.name ?? 'unknown'.tr(),
                    ).textColor(Theme.of(context).appBarTheme.foregroundColor),
                  ),
                  actions: [
                    IconButton(
                      icon: const Icon(Icons.people, shadows: [iconShadow]),
                      onPressed: () {
                        showCupertinoModalBottomSheet(
                          context: context,
                          builder:
                              (context) => _ChatMemberListSheet(roomId: id),
                        );
                      },
                    ),
                    if (isModerator)
                      _ChatRoomActionMenu(id: id, iconShadow: iconShadow),
                    const Gap(8),
                  ],
                ),
                SliverToBoxAdapter(
                  child: Padding(
                    padding: const EdgeInsets.all(16.0),
                    child: Column(
                      crossAxisAlignment: CrossAxisAlignment.start,
                      children: [
                        Text(
                          currentRoom?.description ?? 'descriptionNone'.tr(),
                          style: const TextStyle(fontSize: 16),
                        ),
                      ],
                    ),
                  ),
                ),
              ],
            ),
      ),
    );
  }
}

class _ChatRoomActionMenu extends StatelessWidget {
  final int id;
  final Shadow iconShadow;

  const _ChatRoomActionMenu({required this.id, required this.iconShadow});

  @override
  Widget build(BuildContext context) {
    return PopupMenuButton(
      icon: Icon(Icons.more_vert, shadows: [iconShadow]),
      itemBuilder:
          (context) => [
            PopupMenuItem(
              onTap: () {
                context.router.replace(EditChatRoute(id: id));
              },
              child: Row(
                children: [
                  Icon(
                    Icons.edit,
                    color: Theme.of(context).colorScheme.onSecondaryContainer,
                  ),
                  const Gap(12),
                  const Text('editChatRoom').tr(),
                ],
              ),
            ),
            PopupMenuItem(
              child: Row(
                children: [
                  const Icon(Icons.delete, color: Colors.red),
                  const Gap(12),
                  const Text(
                    'deleteChatRoom',
                    style: TextStyle(color: Colors.red),
                  ).tr(),
                ],
              ),
              onTap: () {
                Navigator.pop(context);
                showDialog(
                  context: context,
                  builder:
                      (context) => AlertDialog(
                        title: const Text('Delete Room'),
                        content: const Text(
                          'Are you sure you want to delete this room? This action cannot be undone.',
                        ),
                        actions: [
                          TextButton(
                            child: const Text('Cancel'),
                            onPressed: () => Navigator.pop(context),
                          ),
                          TextButton(
                            child: const Text(
                              'Delete',
                              style: TextStyle(color: Colors.red),
                            ),
                            onPressed: () async {},
                          ),
                        ],
                      ),
                );
              },
            ),
          ],
    );
  }
}

@freezed
abstract class ChatRoomMemberState with _$ChatRoomMemberState {
  const factory ChatRoomMemberState({
    required List<SnChatMember> members,
    required bool isLoading,
    required int total,
    String? error,
  }) = _ChatRoomMemberState;
}

final chatMemberStateProvider =
    StateNotifierProvider.family<ChatMemberNotifier, ChatRoomMemberState, int>((
      ref,
      roomId,
    ) {
      final apiClient = ref.watch(apiClientProvider);
      return ChatMemberNotifier(apiClient, roomId);
    });

class ChatMemberNotifier extends StateNotifier<ChatRoomMemberState> {
  final int roomId;
  final Dio _apiClient;

  ChatMemberNotifier(this._apiClient, this.roomId)
    : super(const ChatRoomMemberState(members: [], isLoading: false, total: 0));

  Future<void> loadMore({int offset = 0, int take = 20}) async {
    if (state.isLoading) return;
    if (state.total > 0 && state.members.length >= state.total) return;

    state = state.copyWith(isLoading: true, error: null);

    try {
      final response = await _apiClient.get(
        '/chat/$roomId/members',
        queryParameters: {'offset': offset, 'take': take},
      );

      final total = int.parse(response.headers.value('X-Total') ?? '0');
      final List<dynamic> data = response.data;
      final members = data.map((e) => SnChatMember.fromJson(e)).toList();

      state = state.copyWith(
        members: [...state.members, ...members],
        total: total,
        isLoading: false,
      );
    } catch (e) {
      state = state.copyWith(error: e.toString(), isLoading: false);
    }
  }

  void reset() {
    state = const ChatRoomMemberState(members: [], isLoading: false, total: 0);
  }
}

class _ChatMemberListSheet extends HookConsumerWidget {
  final int roomId;
  const _ChatMemberListSheet({required this.roomId});

  @override
  Widget build(BuildContext context, WidgetRef ref) {
    final memberState = ref.watch(chatMemberStateProvider(roomId));
    final memberNotifier = ref.read(chatMemberStateProvider(roomId).notifier);

    useEffect(() {
      Future(() {
        memberNotifier.loadMore();
      });
      return null;
    }, []);

    Future<void> invitePerson() async {
      final result = await showCupertinoModalBottomSheet(
        context: context,
        builder: (context) => const AccountPickerSheet(),
      );
      if (result == null) return;
      try {
        final apiClient = ref.watch(apiClientProvider);
        await apiClient.post(
          '/chat/invites/$roomId',
          data: {'related_user_id': result.id, 'role': 0},
        );
        memberNotifier.reset();
        await memberNotifier.loadMore();
      } catch (err) {
        showErrorAlert(err);
      }
    }

    return Container(
      constraints: BoxConstraints(
        maxHeight: MediaQuery.of(context).size.height * 0.8,
      ),
      child: Material(
        color: Colors.transparent,
        child: Column(
          children: [
            Padding(
              padding: EdgeInsets.only(
                top: 16,
                left: 20,
                right: 16,
                bottom: 12,
              ),
              child: Row(
                children: [
                  Text(
                    'chatMembers'.plural(memberState.total),
                    style: Theme.of(context).textTheme.headlineSmall?.copyWith(
                      fontWeight: FontWeight.w600,
                      letterSpacing: -0.5,
                    ),
                  ),
                  const Spacer(),
                  IconButton(
                    icon: const Icon(Symbols.person_add),
                    onPressed: invitePerson,
                    style: IconButton.styleFrom(
                      minimumSize: const Size(36, 36),
                    ),
                  ),
                  IconButton(
                    icon: const Icon(Symbols.refresh),
                    onPressed: () {
                      memberNotifier.reset();
                      memberNotifier.loadMore();
                    },
                  ),
                  IconButton(
                    icon: const Icon(Symbols.close),
                    onPressed: () => Navigator.pop(context),
                    style: IconButton.styleFrom(
                      minimumSize: const Size(36, 36),
                    ),
                  ),
                ],
              ),
            ),
            const Divider(height: 1),
            Expanded(
              child:
                  memberState.error != null
                      ? Center(child: Text(memberState.error!))
                      : ListView.builder(
                        itemCount: memberState.members.length + 1,
                        itemBuilder: (context, index) {
                          if (index == memberState.members.length) {
                            if (memberState.isLoading) {
                              return const Center(
                                child: Padding(
                                  padding: EdgeInsets.all(16.0),
                                  child: CircularProgressIndicator(),
                                ),
                              );
                            }
                            if (memberState.members.length <
                                memberState.total) {
                              memberNotifier.loadMore(
                                offset: memberState.members.length,
                              );
                            }
                            return const SizedBox.shrink();
                          }

                          final member = memberState.members[index];
                          return ListTile(
                            leading: ProfilePictureWidget(
                              fileId: member.account.profile.pictureId,
                            ),
                            title: Row(
                              spacing: 6,
                              children: [
                                Flexible(child: Text(member.account.nick)),
                                if (member.joinedAt == null)
                                  const Icon(Symbols.pending_actions, size: 20),
                              ],
                            ),
                            subtitle: Row(
                              children: [
                                Text(
                                  member.role >= 100
                                      ? 'permissionOwner'
                                      : member.role >= 50
                                      ? 'permissionModerator'
                                      : 'permissionMember',
                                ).tr(),
                                Text('·').bold().padding(horizontal: 6),
                                Expanded(
                                  child: Text("@${member.account.name}"),
                                ),
                              ],
                            ),
                          );
                        },
                      ),
            ),
          ],
        ),
      ),
    );
  }
}