import 'dart:async';
import 'dart:ui';
import 'package:another_telephony/telephony.dart';
import '../utils/app_theme.dart';
import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
import 'package:flutter_contacts/flutter_contacts.dart';
import 'package:permission_handler/permission_handler.dart';

import '../utils/contact_helper.dart';
import '../utils/database_helper.dart';
import '../utils/protocol_helper.dart';
import '../utils/secure_crypto_helper.dart';
import '../utils/secure_messaging_service.dart';
import '../models/chat_model.dart';
import '../widgets/message_bubble.dart';

class MeshBackgroundPainter extends CustomPainter {
  @override
  void paint(Canvas canvas, Size size) {
    final paint = Paint()..maskFilter = const MaskFilter.blur(BlurStyle.normal, 80);
    
    // Warm accent for groups
    paint.color = const Color(0xFFFFF3E0).withValues(alpha: 0.35); 
    canvas.drawCircle(Offset(size.width * 0.8, size.height * 0.1), 160, paint);
    
    paint.color = const Color(0xFFF3E5F5).withValues(alpha: 0.35);
    canvas.drawCircle(Offset(size.width * 0.2, size.height * 0.8), 200, paint);
  }

  @override
  bool shouldRepaint(covariant CustomPainter oldDelegate) => false;
}

class GroupMessageModel {
  int? id;
  String body;
  String? rawBody;
  int date;
  bool isMe;
  MessageStatus status;
  String? senderPhone;
  String? senderName;
  bool isSecure;
  bool canRetryDecryption;
  String? packetId;
  String? packetMode;
  bool isPendingMultipart;

  GroupMessageModel({
    this.id,
    required this.body,
    this.rawBody,
    required this.date,
    required this.isMe,
    required this.status,
    this.senderPhone,
    this.senderName,
    this.isSecure = false,
    this.canRetryDecryption = false,
    this.packetId,
    this.packetMode,
    this.isPendingMultipart = false,
  });
}

class GroupChatScreen extends StatefulWidget {
  final int groupId;
  final String groupName;

  const GroupChatScreen({
    super.key,
    required this.groupId,
    required this.groupName,
  });

  @override
  State<GroupChatScreen> createState() => _GroupChatScreenState();
}

class _GroupChatScreenState extends State<GroupChatScreen> {
  final Telephony telephony = Telephony.instance;
  static const platform = MethodChannel('com.example.saba/sim_cards');

  final TextEditingController _msgController = TextEditingController();
  final TextEditingController _keyController = TextEditingController();
  final ScrollController _scrollController = ScrollController();

  Color get primaryColor => Theme.of(context).primaryColor;
  final Color backgroundColor = const Color(0xFFF5F7FA);

  List<GroupMessageModel> messages = [];
  List<Map<String, dynamic>> members = [];
  List<Map<String, dynamic>> _simCards = [];
  Map<String, dynamic>? _selectedSim;
  StreamSubscription? _msgSub;

  bool _loadingSims = true;
  String currentGroupName = '';

  @override
  void initState() {
    super.initState();
    currentGroupName = widget.groupName;
    SecureMessagingService.instance.currentChatPhone = 'group_${widget.groupId}';
    DatabaseHelper.instance.markGroupAsRead(widget.groupId);
    _fetchSimCards();
    _loadGroupKeyAndData();
    _scrollController.addListener(_onScroll);
    _msgSub = SecureMessagingService.instance.messageStream.listen((data) {
      if (data['phone'] == 'group_${widget.groupId}') {
        if (!mounted) return;
        final body = data['body'] as String? ?? '';
        final packetId = data['packetId'] as String?;
        final isMultipartComplete = data['isMultipartComplete'] as bool? ?? false;
        final isMeEvent = data['isMe'] as bool? ?? false;

        if (body == 'REFRESH') {
          _loadData();
          return;
        }

        if (packetId != null) {
          setState(() {
            final idx = messages.indexWhere((m) => m.packetId == packetId);
            if (idx != -1) {
              messages[idx].body = body;
              messages[idx].isPendingMultipart = !isMultipartComplete;
              if (isMultipartComplete) {
                messages[idx].status = isMeEvent ? MessageStatus.sent : MessageStatus.received;
              }
            } else {
              // If it's a new fragmented message or just completed but not in list
              _loadData();
            }
          });
        } else {
          _loadData();
        }
      }
    });
    _keyController.addListener(() {
      if (mounted) _onKeyChanged();
    });
  }

  void _onScroll() {
    if (!_scrollController.hasClients) return;
    // Group chat might need pagination in the future, 
    // for now we just monitor the state to prevent jumps.
  }

  @override
  void dispose() {
    if (SecureMessagingService.instance.currentChatPhone == 'group_${widget.groupId}') {
      SecureMessagingService.instance.currentChatPhone = null;
    }
    _msgSub?.cancel();
    _msgController.dispose();
    _keyController.dispose();
    _scrollController.dispose();
    super.dispose();
  }

  Future<void> _loadGroupKeyAndData() async {
    final groups = await DatabaseHelper.instance.getGroups();
    final group = groups.cast<Map<String, dynamic>?>().firstWhere(
          (g) => g?['id'] == widget.groupId,
          orElse: () => null,
        );
    if (group != null && (group['group_key'] as String?)?.isNotEmpty == true) {
      _keyController.text = group['group_key'] as String;
    }
    await _loadData();
  }

  void _onKeyChanged() {
    DatabaseHelper.instance.updateGroupKey(widget.groupId, _keyController.text);
    _loadData();
  }

  bool _isSecurePlaceholderBody(String body) {
    return body.startsWith('پیام امن گروهی') ||
        body.startsWith('بازگشایی پیام امن گروهی') ||
        body.contains(' ::PAYLOAD::');
  }

  String? _extractPayload(String body) {
    const separator = ' ::PAYLOAD::';
    final splitIndex = body.lastIndexOf(separator);
    if (splitIndex == -1) return null;
    final payload = body.substring(splitIndex + separator.length).trim();
    return payload.isEmpty ? null : payload;
  }

  Future<void> _handleRetryDecryption(GroupMessageModel msg) async {
    String? payload = _extractPayload(msg.body);
    if (payload == null && msg.rawBody != null) {
      payload = ProtocolHelper.parseMessage(msg.rawBody!)['payload'] as String?;
    }
    if (payload == null) return;

    final keyController = TextEditingController(text: _keyController.text.trim());
    showDialog(
      context: context,
      builder: (ctx) => AlertDialog(
        shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(15)),
        title: const Text('بازگشایی دستی پیام گروه'),
        content: TextField(
          controller: keyController,
          decoration: const InputDecoration(
            hintText: 'کلید گروه',
            border: OutlineInputBorder(),
          ),
        ),
        actions: [
          TextButton(onPressed: () => Navigator.pop(ctx), child: const Text('لغو')),
          ElevatedButton(
            onPressed: () async {
              if (keyController.text.trim().isEmpty) return;
              final decrypted = await SecureMessagingService.instance.decryptWithKey(
                payload!,
                keyController.text.trim(),
              );
              if (!mounted) return;
              Navigator.pop(ctx);
              if (decrypted != null) {
                _keyController.text = keyController.text.trim();
                ScaffoldMessenger.of(context).showSnackBar(
                  const SnackBar(content: Text('پیام گروهی بازگشایی شد.')),
                );
                _loadData();
              } else {
                ScaffoldMessenger.of(context).showSnackBar(
                  const SnackBar(content: Text('کلید گروه نادرست است.')),
                );
              }
            },
            child: const Text('بازگشایی'),
          ),
        ],
      ),
    );
  }

  Future<Map<String, dynamic>> _resolveGroupMessageState(String rawBody,
      {bool isMe = false, bool dbIsSecure = false}) async {
    final parsed = ProtocolHelper.parseMessage(rawBody);
    final type = parsed['type'] as String;
    final key = _keyController.text.trim();

    String body = rawBody;
    bool isSecure = dbIsSecure || type != 'plain' || rawBody.contains(' ::PAYLOAD::');
    bool canRetryDecryption = false;

    if (type == 'sym' && parsed['isGroup'] == true) {
      final payload = parsed['payload'] as String?;
      if (payload != null && key.isNotEmpty) {
        final decrypted = await SecureMessagingService.instance.decryptWithKey(payload, key);
        if (decrypted != null) {
          body = decrypted;
        } else {
          final label = isMe ? 'ارسال شده' : 'دریافت شد';
          body = 'بازگشایی پیام امن گروهی $label ناموفق بود. کلید گروه را بررسی کنید. ::PAYLOAD::$payload';
          canRetryDecryption = true;
        }
      } else if (payload != null) {
        final label = isMe ? 'ارسال شده' : 'دریافت شد';
        body = 'پیام امن گروهی $label. برای مشاهده، کلید گروه را وارد کنید. ::PAYLOAD::$payload';
        canRetryDecryption = true;
      }
    } else if (type == 'sfra' && parsed['isGroup'] == true) {
      body = 'در حال دریافت قطعات... (${parsed['partNo']}/${parsed['totalParts']})';
      isSecure = true;
    } else if (rawBody.contains(' ::PAYLOAD::')) {
      canRetryDecryption = true;
    }

    return {
      'body': body,
      'isSecure': isSecure,
      'canRetryDecryption': canRetryDecryption,
      'packetId': parsed['packetId'],
      'packetMode': type == 'plain' ? null : (type == 'afrag' ? 'AE' : 'SYM'),
      'isPendingMultipart': type == 'sfra' || type == 'afrag',
    };
  }

  Future<void> _fetchSimCards() async {
    if (!await Permission.phone.request().isGranted) {
      if (mounted) setState(() => _loadingSims = false);
      return;
    }
    try {
      final List<dynamic> result = await platform.invokeMethod('getSimCards');
      final cleanList = result.map((e) {
        final rawMap = e as Map<Object?, Object?>;
        return rawMap.map((key, value) => MapEntry(key.toString(), value));
      }).toList();
      if (!mounted) return;
      setState(() {
        _simCards = cleanList;
        if (_simCards.isNotEmpty) _selectedSim = _simCards.first;
        _loadingSims = false;
      });
    } catch (_) {
      if (mounted) setState(() => _loadingSims = false);
    }
  }

  bool _isLoading = false;
  bool _needsReload = false;

  Future<void> _loadData() async {
    if (_isLoading) {
      _needsReload = true;
      return;
    }
    _isLoading = true;
    _needsReload = false;

    try {
      final dbMessages = await DatabaseHelper.instance.getGroupMessages(widget.groupId);
      final dbMembers = await DatabaseHelper.instance.getGroupMembers(widget.groupId);

      final uiMessages = <GroupMessageModel>[];
      for (final m in dbMessages) {
        final raw = m['body'] as String;
        final senderPhone = m['sender_phone'] as String?;
        final senderName = senderPhone != null ? ContactHelper.getName(senderPhone) : 'من';
        final dbIsSecure = (m['is_secure'] as int? ?? 0) == 1;
        final resolved = await _resolveGroupMessageState(raw, isMe: senderPhone == null, dbIsSecure: dbIsSecure);

        uiMessages.add(GroupMessageModel(
          id: m['id'] as int?,
          body: resolved['body'] as String,
          rawBody: raw,
          date: m['date'] as int,
          isMe: senderPhone == null,
          status: MessageStatus.received,
          senderPhone: senderPhone,
          senderName: senderName,
          isSecure: resolved['isSecure'] as bool,
          canRetryDecryption:
              resolved['canRetryDecryption'] as bool || _isSecurePlaceholderBody(resolved['body'] as String),
          packetId: resolved['packetId'] as String?,
          packetMode: resolved['packetMode'] as String?,
          isPendingMultipart: resolved['isPendingMultipart'] as bool? ?? false,
        ));
      }

      if (mounted) {
        setState(() {
          messages = uiMessages;
          members = dbMembers;
        });
      }
    } finally {
      _isLoading = false;
      if (_needsReload) _loadData();
    }
  }

  void _deleteMessage(int messageId) {
    showDialog(
      context: context,
      builder: (ctx) => AlertDialog(
        shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(15)),
        title: const Text('حذف پیام'),
        content: const Text('آیا مطمئن هستید؟'),
        actions: [
          TextButton(onPressed: () => Navigator.pop(ctx), child: const Text('لغو')),
          ElevatedButton(
            style: ElevatedButton.styleFrom(backgroundColor: Colors.red, foregroundColor: Colors.white),
            onPressed: () async {
              Navigator.pop(ctx);
              await DatabaseHelper.instance.deleteGroupMessage(messageId);
              _loadData();
            },
            child: const Text('حذف'),
          ),
        ],
      ),
    );
  }

  void _editGroupName() {
    final nameController = TextEditingController(text: currentGroupName);
    showDialog(
      context: context,
      builder: (ctx) => AlertDialog(
        shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(15)),
        title: const Text('تغییر نام گروه'),
        content: TextField(
          controller: nameController,
          decoration: InputDecoration(
            labelText: 'نام جدید',
            border: OutlineInputBorder(borderRadius: BorderRadius.circular(10)),
          ),
        ),
        actions: [
          TextButton(onPressed: () => Navigator.pop(ctx), child: const Text('لغو')),
          ElevatedButton(
            style: ElevatedButton.styleFrom(backgroundColor: primaryColor, foregroundColor: Colors.white),
            onPressed: () async {
              if (nameController.text.trim().isEmpty) return;
              await DatabaseHelper.instance.updateGroupName(widget.groupId, nameController.text.trim());
              if (!mounted) return;
              setState(() => currentGroupName = nameController.text.trim());
              Navigator.pop(ctx);
            },
            child: const Text('ذخیره'),
          ),
        ],
      ),
    );
  }

  void _showGroupInfo() {
    showDialog(
      context: context,
      builder: (context) {
        return StatefulBuilder(
          builder: (context, setStateDialog) {
            return AlertDialog(
              shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(15)),
              title: Row(
                mainAxisAlignment: MainAxisAlignment.spaceBetween,
                children: [
                  const Text('مدیریت اعضا', style: TextStyle(fontSize: 18, fontWeight: FontWeight.bold)),
                  IconButton(
                    icon: Container(
                      padding: const EdgeInsets.all(4),
                      decoration: BoxDecoration(
                        color: primaryColor.withValues(alpha: 0.1),
                        shape: BoxShape.circle,
                      ),
                      child: Icon(Icons.person_add, color: primaryColor, size: 20),
                    ),
                    onPressed: () {
                      Navigator.pop(context);
                      _addNewMember();
                    },
                  ),
                ],
              ),
              content: SizedBox(
                width: double.maxFinite,
                child: members.isEmpty
                    ? const Center(child: Text('هیچ عضوی وجود ندارد', style: TextStyle(color: Colors.grey)))
                    : ListView.separated(
                        shrinkWrap: true,
                        itemCount: members.length,
                        separatorBuilder: (_, __) => const Divider(),
                        itemBuilder: (_, index) {
                          final member = members[index];
                          return ListTile(
                            contentPadding: EdgeInsets.zero,
                            leading: CircleAvatar(
                              backgroundColor: Colors.orange.shade100,
                              child: Text(
                                (member['name'] as String)[0],
                                style: TextStyle(color: Colors.orange.shade900),
                              ),
                            ),
                            title: Text(
                              member['name'] as String,
                              style: const TextStyle(fontWeight: FontWeight.bold),
                            ),
                            subtitle: Text(member['phone'] as String),
                            trailing: IconButton(
                              icon: const Icon(Icons.delete_outline, color: Colors.red),
                              onPressed: () async {
                                await DatabaseHelper.instance.removeGroupMember(
                                  widget.groupId,
                                  member['phone'] as String,
                                );
                                final newMembers = await DatabaseHelper.instance.getGroupMembers(widget.groupId);
                                if (!mounted) return;
                                setState(() => members = newMembers);
                                setStateDialog(() {});
                              },
                            ),
                          );
                        },
                      ),
              ),
              actions: [
                TextButton(onPressed: () => Navigator.pop(context), child: const Text('بستن')),
              ],
            );
          },
        );
      },
    );
  }

  Future<void> _addNewMember() async {
    showDialog(
      context: context,
      barrierDismissible: false,
      builder: (_) => const Center(child: CircularProgressIndicator()),
    );
    final contacts = await ContactHelper.getContactsLight();
    if (mounted) Navigator.pop(context);

    if (contacts.isEmpty) {
      if (mounted) {
        ScaffoldMessenger.of(context).showSnackBar(const SnackBar(content: Text('مخاطبی یافت نشد')));
      }
      return;
    }

    if (!mounted) return;
    final result = await showSearch<Map<String, String>?>(
      context: context,
      delegate: ContactsSearchDelegate(contacts),
    );

    if (result == null) return;
    final added = await DatabaseHelper.instance.addMemberToGroup(
      widget.groupId,
      result['name']!,
      result['phone']!,
    );
    if (!mounted) return;

    if (added) {
      await _loadData();
      ScaffoldMessenger.of(context).showSnackBar(const SnackBar(content: Text('عضو جدید اضافه شد')));
    } else {
      ScaffoldMessenger.of(context).showSnackBar(
        const SnackBar(content: Text('این عضو قبلاً در گروه وجود دارد')),
      );
    }
  }

  Future<void> _sendGroupMessage() async {
    final text = _msgController.text.trim();
    final key = _keyController.text.trim();
    if (text.isEmpty) return;

    String? rawBody;
    if (key.isNotEmpty) {
      final crypto = SecureCryptoHelper();
      rawBody = '@G:SYM|${await crypto.encryptSymmetric(text, key)}';
    }

    final tempMsg = GroupMessageModel(
      body: text,
      rawBody: rawBody,
      date: DateTime.now().millisecondsSinceEpoch,
      isMe: true,
      status: MessageStatus.sending,
      senderName: 'من',
      isSecure: key.isNotEmpty,
    );

    setState(() {
      messages.insert(0, tempMsg);
      _msgController.clear();
    });

    try {
      final groupMemberPhones = members.map((m) => m['phone'] as String).toList();
      await SecureMessagingService.instance.sendGroupSecureMessage(
        widget.groupId,
        groupMemberPhones,
        text,
        key,
      );

      if (!mounted) return;
      setState(() => tempMsg.status = MessageStatus.sent);
      Future.delayed(const Duration(milliseconds: 1200), _loadData);
    } catch (_) {
      if (!mounted) return;
      setState(() => tempMsg.status = MessageStatus.failed);
    }
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      backgroundColor: AppTheme.darkBg,
      extendBodyBehindAppBar: true,
      resizeToAvoidBottomInset: true,
      appBar: PreferredSize(
        preferredSize: const Size.fromHeight(kToolbarHeight + 8),
        child: AppTheme.glassWrapper(
          radius: 0,
          sigma: 18,
          child: AppBar(
            backgroundColor: Colors.transparent,
            elevation: 0,
            leading: IconButton(
              icon: const Icon(Icons.arrow_back, color: Colors.white),
              onPressed: () => Navigator.of(context).pop(),
            ),
            title: InkWell(
              onTap: _editGroupName,
              overlayColor: WidgetStateProperty.all(Colors.transparent),
              child: Row(
                mainAxisSize: MainAxisSize.min,
                children: [
                  Hero(
                    tag: 'avatar_${currentGroupName}_group',
                    child: Container(
                      width: 38,
                      height: 38,
                      decoration: const BoxDecoration(
                        shape: BoxShape.circle,
                        gradient: LinearGradient(
                          colors: [Colors.orange, Colors.orangeAccent],
                        ),
                      ),
                      child: const Center(
                        child: Icon(Icons.groups, color: Colors.white, size: 22),
                      ),
                    ),
                  ),
                  const SizedBox(width: 10),
                  Column(
                    crossAxisAlignment: CrossAxisAlignment.start,
                    children: [
                      Text(currentGroupName, style: const TextStyle(fontSize: 16, fontWeight: FontWeight.bold, color: Colors.white)),
                      Text('${members.length} عضو', style: const TextStyle(fontSize: 11, color: Colors.white70)),
                    ],
                  ),
                  const SizedBox(width: 6),
                  const Icon(Icons.edit_outlined, size: 14, color: Colors.white70),
                ],
              ),
            ),
            actions: [
              IconButton(
                icon: const Icon(Icons.group_outlined, color: Colors.white),
                tooltip: 'مدیریت اعضا',
                onPressed: _showGroupInfo,
              ),
            ],
          ),
        ),
      ),
      body: Stack(
        children: [
          Positioned.fill(child: CustomPaint(painter: MeshBackgroundPainter())),
          Column(
            children: [
              SizedBox(height: MediaQuery.of(context).padding.top + kToolbarHeight + 8),
              Expanded(
            child: messages.isEmpty
                ? Center(
                    child: Column(
                      mainAxisAlignment: MainAxisAlignment.center,
                      children: [
                        Icon(Icons.mark_chat_unread_outlined, size: 60, color: Colors.grey[300]),
                        const SizedBox(height: 10),
                        Text('پیامی ارسال نشده است', style: TextStyle(color: Colors.grey[500])),
                      ],
                    ),
                  )
                : ListView.builder(
                    key: const PageStorageKey('group_chat_list'),
                    controller: _scrollController,
                    reverse: true,
                    padding: const EdgeInsets.symmetric(horizontal: 10, vertical: 20),
                    itemCount: messages.length,
                    itemBuilder: (context, index) {
                      final msg = messages[index];
                      return GestureDetector(
                        onLongPress: () {
                          if (msg.id != null) {
                            _deleteMessage(msg.id!);
                          }
                        },
                        child: Column(
                          crossAxisAlignment: msg.isMe ? CrossAxisAlignment.end : CrossAxisAlignment.start,
                          children: [
                            if (!msg.isMe && msg.senderName != null)
                              Padding(
                                padding: const EdgeInsets.only(left: 12, bottom: 4),
                                child: Text(
                                  msg.senderName!,
                                  style: const TextStyle(
                                    fontSize: 10,
                                    color: Colors.indigo,
                                    fontWeight: FontWeight.bold,
                                  ),
                                ),
                              ),
                            MessageBubble(
                              body: msg.body,
                              rawBody: msg.rawBody,
                              date: msg.date,
                              isMe: msg.isMe,
                              status: msg.status,
                              isSecure: msg.isSecure,
                              canRetryDecryption: msg.canRetryDecryption,
                              onRetryDecryption: () => _handleRetryDecryption(msg),
                              packetMode: msg.packetMode,
                              isPendingMultipart: msg.isPendingMultipart,
                            ),
                          ],
                        ),
                      );
                    },
                  ),
          ),
              AppTheme.glassWrapper(
                radius: 0,
                sigma: 15,
                child: Container(
                  padding: const EdgeInsets.fromLTRB(16, 12, 16, 24),
                  decoration: BoxDecoration(
                    color: Colors.white.withValues(alpha: 0.03),
                    border: Border(
                      top: BorderSide(color: Colors.white.withValues(alpha: 0.08), width: 0.5),
                    ),
                  ),
                  child: Column(
                    mainAxisSize: MainAxisSize.min,
                    children: [
                      if (!_loadingSims && _simCards.length > 1)
                        SizedOverflowBox(
                          size: const Size.fromHeight(35),
                          child: ListView.builder(
                            scrollDirection: Axis.horizontal,
                            itemCount: _simCards.length,
                            itemBuilder: (context, index) {
                              final sim = _simCards[index];
                              return Padding(
                                padding: const EdgeInsets.only(right: 8),
                                child: ChoiceChip(
                                  label: Text(sim['displayName']?.toString() ?? 'SIM ${index + 1}'),
                                  selected: _selectedSim == sim,
                                  onSelected: (_) => setState(() => _selectedSim = sim),
                                ),
                              );
                            },
                          ),
                        ),
                      const SizedBox(height: 12),
                      Row(
                        children: [
                          Expanded(
                            child: TextField(
                              controller: _keyController,
                              style: const TextStyle(color: Colors.white, fontSize: 13),
                              decoration: InputDecoration(
                                hintText: 'کلید امنیتی گروه (اختیاری)',
                                hintStyle: const TextStyle(color: Colors.white30),
                                prefixIcon: const Icon(Icons.vpn_key_rounded, size: 18, color: Colors.orangeAccent),
                                filled: true,
                                fillColor: Colors.white.withValues(alpha: 0.05),
                                contentPadding: const EdgeInsets.symmetric(horizontal: 16, vertical: 0),
                                border: OutlineInputBorder(
                                  borderRadius: BorderRadius.circular(12),
                                  borderSide: BorderSide.none,
                                ),
                              ),
                            ),
                          ),
                        ],
                      ),
                      const SizedBox(height: 12),
                      Row(
                        children: [
                          Expanded(
                            child: TextField(
                              controller: _msgController,
                              minLines: 1,
                              maxLines: 4,
                              style: const TextStyle(color: Colors.white),
                              decoration: InputDecoration(
                                hintText: 'پیام گروهی...',
                                hintStyle: const TextStyle(color: Colors.white30),
                                filled: true,
                                fillColor: Colors.white.withValues(alpha: 0.05),
                                contentPadding: const EdgeInsets.symmetric(horizontal: 16, vertical: 12),
                                border: OutlineInputBorder(
                                  borderRadius: BorderRadius.circular(20),
                                  borderSide: BorderSide.none,
                                ),
                              ),
                            ),
                          ),
                          const SizedBox(width: 12),
                          Container(
                            height: 48,
                            width: 48,
                            decoration: BoxDecoration(
                              shape: BoxShape.circle,
                              gradient: const LinearGradient(
                                colors: [Colors.indigo, Colors.indigoAccent],
                              ),
                              boxShadow: [
                                BoxShadow(
                                  color: Colors.indigo.withValues(alpha: 0.3),
                                  blurRadius: 12,
                                  spreadRadius: 1,
                                ),
                              ],
                            ),
                            child: IconButton(
                              icon: const Icon(Icons.send_rounded, color: Colors.white, size: 22),
                              onPressed: _sendGroupMessage,
                            ),
                          ),
                        ],
                      ),
                    ],
                  ),
                ),
              ),
            ],
          ),
        ],
      ),
    );
  }
}

class ContactsSearchDelegate extends SearchDelegate<Map<String, String>?> {
  final List<Contact> contacts;

  ContactsSearchDelegate(this.contacts);

  @override
  String? get searchFieldLabel => 'جست‌وجو نام مخاطب...';

  @override
  List<Widget>? buildActions(BuildContext context) {
    return [
      if (query.isNotEmpty)
        IconButton(
          icon: const Icon(Icons.clear),
          onPressed: () => query = '',
        ),
    ];
  }

  @override
  Widget? buildLeading(BuildContext context) {
    return IconButton(
      icon: const Icon(Icons.arrow_back),
      onPressed: () => close(context, null),
    );
  }

  @override
  Widget buildResults(BuildContext context) => _buildList(context);

  @override
  Widget buildSuggestions(BuildContext context) => _buildList(context);

  Widget _buildList(BuildContext context) {
    final filtered = query.isEmpty
        ? contacts
        : contacts.where((c) => c.displayName.toLowerCase().contains(query.toLowerCase())).toList();

    if (filtered.isEmpty) {
      return const Center(child: Text('نتیجه‌ای یافت نشد.'));
    }

    return ListView.builder(
      itemCount: filtered.length,
      itemBuilder: (context, index) {
        final contact = filtered[index];
        return ListTile(
          leading: CircleAvatar(
            backgroundColor: Colors.indigo.shade100,
            child: Text(
              contact.displayName.isNotEmpty ? contact.displayName[0] : '?',
              style: TextStyle(color: Colors.indigo.shade900),
            ),
          ),
          title: Text(contact.displayName),
          onTap: () => _onContactSelect(context, contact.id),
        );
      },
    );
  }

  Future<void> _onContactSelect(BuildContext context, String contactId) async {
    showDialog(
      context: context,
      barrierDismissible: false,
      builder: (_) => const Center(child: CircularProgressIndicator()),
    );
    try {
      final fullContact = await ContactHelper.getFullContact(contactId);
      if (context.mounted) Navigator.pop(context);
      if (fullContact == null || fullContact.phones.isEmpty) return;

      if (fullContact.phones.length == 1) {
        close(context, {
          'name': fullContact.displayName,
          'phone': fullContact.phones.first.number,
        });
      } else {
        _showPhoneSelection(context, fullContact);
      }
    } catch (_) {
      if (context.mounted) Navigator.pop(context);
    }
  }

  void _showPhoneSelection(BuildContext context, Contact contact) {
    showDialog(
      context: context,
      builder: (_) => SimpleDialog(
        title: Text(contact.displayName),
        children: contact.phones
            .map(
              (p) => SimpleDialogOption(
                onPressed: () {
                  Navigator.pop(context);
                  close(context, {
                    'name': contact.displayName,
                    'phone': p.number,
                  });
                },
                child: Text(p.number),
              ),
            )
            .toList(),
      ),
    );
  }
}