import 'dart:async';

import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:go_router/go_router.dart';

import '../../core/msn_api.dart';
import '../../core/session_controller.dart';
import '../../models/context_member_model.dart';
import '../../models/room_model.dart';
import '../../theme/toss_theme.dart';
import '../profile/user_profile_sheet.dart';

class SearchPage extends ConsumerStatefulWidget {
  const SearchPage({super.key, required this.contextId});

  final String contextId;

  @override
  ConsumerState<SearchPage> createState() => _SearchPageState();
}

class _SearchPageState extends ConsumerState<SearchPage> {
  final _q = TextEditingController();
  List<Map<String, dynamic>> _messageResults = [];
  List<RoomModel> _rooms = [];
  List<ContextMember> _friends = [];
  bool _busy = false;
  bool _loadedLists = false;
  int _segment = 0;

  @override
  void initState() {
    super.initState();
    WidgetsBinding.instance.addPostFrameCallback((_) => _ensureLists());
  }

  @override
  void dispose() {
    _q.dispose();
    super.dispose();
  }

  Future<void> _ensureLists() async {
    if (_loadedLists || widget.contextId.isEmpty) return;
    setState(() => _busy = true);
    try {
      final api = ref.read(msnApiProvider);
      final rooms = await api.listRooms(widget.contextId);
      final members = await api.listContextMembers(widget.contextId);
      if (!mounted) return;
      setState(() {
        _rooms = rooms;
        _friends = members;
        _loadedLists = true;
      });
    } finally {
      if (mounted) setState(() => _busy = false);
    }
  }

  Future<void> _runMessageSearch() async {
    if (widget.contextId.isEmpty) return;
    setState(() => _busy = true);
    try {
      final r = await ref.read(msnApiProvider).searchMessages(widget.contextId, _q.text);
      if (!mounted) return;
      setState(() => _messageResults = r);
    } finally {
      if (mounted) setState(() => _busy = false);
    }
  }

  String get _needle => _q.text.trim().toLowerCase();

  List<RoomModel> get _filteredRooms {
    if (_needle.isEmpty) return _rooms;
    return _rooms.where((r) {
      final name = (r.name ?? (r.isGroup ? '그룹' : '1:1')).toLowerCase();
      final last = (r.lastBody ?? '').toLowerCase();
      return name.contains(_needle) || last.contains(_needle);
    }).toList();
  }

  List<ContextMember> get _filteredFriends {
    if (_needle.isEmpty) return _friends;
    return _friends.where((m) {
      final name = m.displayName.toLowerCase();
      final st = (m.statusMessage ?? '').toLowerCase();
      return name.contains(_needle) ||
          m.userId.toLowerCase().contains(_needle) ||
          st.contains(_needle);
    }).toList();
  }

  @override
  Widget build(BuildContext context) {
    final tt = Theme.of(context).textTheme;
    final myId = ref.watch(sessionProvider).value?.userId;

    return Scaffold(
      backgroundColor: TossColors.bg,
      appBar: AppBar(title: const Text('검색')),
      body: Column(
        children: [
          Padding(
            padding: const EdgeInsets.fromLTRB(16, 12, 16, 8),
            child: SegmentedButton<int>(
              segments: const [
                ButtonSegment(value: 0, label: Text('메시지'), icon: Icon(Icons.search, size: 18)),
                ButtonSegment(value: 1, label: Text('방'), icon: Icon(Icons.chat_bubble_outline, size: 18)),
                ButtonSegment(value: 2, label: Text('친구'), icon: Icon(Icons.people_outline, size: 18)),
              ],
              selected: {_segment},
              onSelectionChanged: (s) {
                if (s.isEmpty) return;
                setState(() => _segment = s.first);
              },
            ),
          ),
          Padding(
            padding: const EdgeInsets.fromLTRB(16, 0, 16, 8),
            child: Row(
              children: [
                Expanded(
                  child: TextField(
                    controller: _q,
                    decoration: InputDecoration(
                      hintText: _segment == 0
                          ? '이 맥락에서 메시지 검색'
                          : _segment == 1
                              ? '방 이름 또는 미리보기로 필터'
                              : '이름·상태로 친구 필터',
                      prefixIcon: const Icon(Icons.search_rounded, color: TossColors.textSecondary),
                    ),
                    onChanged: (_) {
                      if (_segment != 0) setState(() {});
                    },
                    onSubmitted: (_) {
                      if (_segment == 0) unawaited(_runMessageSearch());
                    },
                  ),
                ),
                const SizedBox(width: 8),
                if (_segment == 0)
                  Material(
                    color: TossColors.blue,
                    borderRadius: BorderRadius.circular(12),
                    child: IconButton(
                      onPressed: _busy ? null : () => unawaited(_runMessageSearch()),
                      icon: _busy
                          ? const SizedBox(
                              width: 22,
                              height: 22,
                              child: CircularProgressIndicator(strokeWidth: 2, color: Colors.white),
                            )
                          : const Icon(Icons.arrow_forward_rounded, color: Colors.white),
                    ),
                  ),
              ],
            ),
          ),
          Expanded(
            child: _busy && !_loadedLists && _segment != 0
                ? const Center(child: CircularProgressIndicator(color: TossColors.blue))
                : _segment == 0
                    ? _buildMessageList(tt)
                    : _segment == 1
                        ? _buildRoomList(tt)
                        : _buildFriendList(tt, myId),
          ),
        ],
      ),
    );
  }

  Widget _buildMessageList(TextTheme tt) {
    return ListView.separated(
      padding: const EdgeInsets.fromLTRB(16, 0, 16, 24),
      itemCount: _messageResults.length,
      separatorBuilder: (_, __) => const SizedBox(height: 8),
      itemBuilder: (context, i) {
        final r = _messageResults[i];
        return Material(
          color: TossColors.surface,
          borderRadius: BorderRadius.circular(14),
          child: InkWell(
            borderRadius: BorderRadius.circular(14),
            onTap: () {
              final roomId = r['roomId'] as String?;
              if (roomId == null) return;
              context.push('/chat?roomId=$roomId&contextId=${widget.contextId}');
            },
            child: Ink(
              decoration: BoxDecoration(
                borderRadius: BorderRadius.circular(14),
                border: Border.all(color: TossColors.line),
              ),
              child: Padding(
                padding: const EdgeInsets.all(16),
                child: Column(
                  crossAxisAlignment: CrossAxisAlignment.start,
                  children: [
                    Text(r['body'] as String? ?? '', style: tt.bodyLarge),
                    const SizedBox(height: 6),
                    Text('방 ${r['roomId']}', style: tt.bodySmall),
                  ],
                ),
              ),
            ),
          ),
        );
      },
    );
  }

  Widget _buildRoomList(TextTheme tt) {
    final list = _filteredRooms;
    if (list.isEmpty) {
      return Center(child: Text(_emptyHint('방')));
    }
    return ListView.separated(
      padding: const EdgeInsets.fromLTRB(16, 0, 16, 24),
      itemCount: list.length,
      separatorBuilder: (_, __) => const SizedBox(height: 8),
      itemBuilder: (context, i) {
        final r = list[i];
        final title = r.name ?? (r.isGroup ? '그룹 채팅' : '1:1 채팅');
        final sub = r.lastBody ?? '메시지 없음';
        return Material(
          color: TossColors.surface,
          borderRadius: BorderRadius.circular(14),
          child: InkWell(
            borderRadius: BorderRadius.circular(14),
            onTap: () => context.push('/chat?roomId=${r.id}&contextId=${widget.contextId}'),
            child: Ink(
              decoration: BoxDecoration(
                borderRadius: BorderRadius.circular(14),
                border: Border.all(color: TossColors.line),
              ),
              child: Padding(
                padding: const EdgeInsets.all(16),
                child: Column(
                  crossAxisAlignment: CrossAxisAlignment.start,
                  children: [
                    Text(title, style: tt.titleMedium),
                    const SizedBox(height: 4),
                    Text(sub, style: tt.bodySmall, maxLines: 2, overflow: TextOverflow.ellipsis),
                  ],
                ),
              ),
            ),
          ),
        );
      },
    );
  }

  Widget _buildFriendList(TextTheme tt, String? myId) {
    final list = _filteredFriends;
    if (list.isEmpty) {
      return Center(child: Text(_emptyHint('친구')));
    }
    return ListView.separated(
      padding: const EdgeInsets.fromLTRB(16, 0, 16, 24),
      itemCount: list.length,
      separatorBuilder: (_, __) => const SizedBox(height: 8),
      itemBuilder: (context, i) {
        final m = list[i];
        final isSelf = myId != null && m.userId == myId;
        return Material(
          color: TossColors.surface,
          borderRadius: BorderRadius.circular(14),
          child: InkWell(
            borderRadius: BorderRadius.circular(14),
            onTap: () async {
              if (isSelf) {
                await showUserProfileSheet(
                  context,
                  ref,
                  contextId: widget.contextId,
                  userId: m.userId,
                );
              } else {
                final roomId =
                    await ref.read(msnApiProvider).openDirectRoom(widget.contextId, m.userId);
                if (!context.mounted) return;
                await context.push('/chat?roomId=$roomId&contextId=${widget.contextId}');
              }
            },
            child: Ink(
              decoration: BoxDecoration(
                borderRadius: BorderRadius.circular(14),
                border: Border.all(color: TossColors.line),
              ),
              child: Padding(
                padding: const EdgeInsets.symmetric(horizontal: 16, vertical: 14),
                child: Row(
                  children: [
                    Expanded(
                      child: Column(
                        crossAxisAlignment: CrossAxisAlignment.start,
                        children: [
                          Text(
                            m.displayName.isNotEmpty ? m.displayName : m.userId,
                            style: tt.titleMedium,
                          ),
                          if (m.statusMessage != null && m.statusMessage!.isNotEmpty)
                            Text(m.statusMessage!, style: tt.bodySmall, maxLines: 1),
                        ],
                      ),
                    ),
                    IconButton(
                      icon: const Icon(Icons.person_outline_rounded),
                      onPressed: () async {
                        await showUserProfileSheet(
                          context,
                          ref,
                          contextId: widget.contextId,
                          userId: m.userId,
                        );
                      },
                    ),
                  ],
                ),
              ),
            ),
          ),
        );
      },
    );
  }

  String _emptyHint(String kind) {
    if (_needle.isEmpty) return '목록을 불러오는 중이거나 $kind가 없습니다';
    return '검색어와 일치하는 $kind가 없습니다';
  }
}