import 'package:flutter/material.dart';
import 'package:driver/core/l10n/app_localizations.dart';
import '../../../core/design/tokens.dart';
import '../../../core/ui/tripz_text_field.dart';
import '../../trip/data/driver_trip_repository.dart';
import '../../trip/data/models/chat_message_model.dart';
import '../../../core/storage/token_store.dart';
import '../../../core/di.dart';

/// شاشة دردشة السائق مع العميل داخل الرحلة.
///
/// تُستخدم من شاشة تنفيذ الرحلة (Q4).
class DriverChatScreen extends StatefulWidget {
  final String tripId;

  const DriverChatScreen({super.key, required this.tripId});

  @override
  State<DriverChatScreen> createState() => _DriverChatScreenState();
}

class _DriverChatScreenState extends State<DriverChatScreen> {
  final TextEditingController _controller = TextEditingController();
  final ScrollController _scrollController = ScrollController();
  late final DriverTripRepository _repo;
  List<ChatMessageModel> _messages = [];
  bool _loading = true;
  bool _sending = false;

  @override
  void initState() {
    super.initState();
    _repo = DriverTripRepository(getIt());
    _loadMessages();
  }

  Future<void> _loadMessages() async {
    final userId = await getIt<TokenStore>().access();
    final messages = await _repo.getMessages(widget.tripId, currentUserId: userId);
    if (mounted) {
      setState(() {
        _messages = messages;
        _loading = false;
      });
      _scrollToBottom();
    }
  }

  Future<void> _sendMessage() async {
    final text = _controller.text.trim();
    if (text.isEmpty || _sending) return;

    setState(() => _sending = true);
    _controller.clear();

    final userId = await getIt<TokenStore>().access();
    final msg = await _repo.sendMessage(widget.tripId, text, currentUserId: userId);
    if (msg != null && mounted) {
      setState(() => _messages.add(msg));
      _scrollToBottom();
    }
    if (mounted) setState(() => _sending = false);
  }

  void _scrollToBottom() {
    Future.delayed(const Duration(milliseconds: 100), () {
      if (_scrollController.hasClients) {
        _scrollController.animateTo(
          _scrollController.position.maxScrollExtent,
          duration: const Duration(milliseconds: 200),
          curve: Curves.easeOut,
        );
      }
    });
  }

  @override
  void dispose() {
    _controller.dispose();
    _scrollController.dispose();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    final l10n = AppLocalizations.of(context)!;
    final cs = Theme.of(context).colorScheme;

    return Scaffold(
      appBar: AppBar(
        title: Text(l10n.chat),
      ),
      body: Column(
        children: [
          // الرسائل
          Expanded(
            child: _loading
                ? const Center(child: CircularProgressIndicator())
                : _messages.isEmpty
                    ? Center(
                        child: Text(
                          l10n.noMessagesYet,
                          style: TextStyle(color: cs.onSurfaceVariant),
                        ),
                      )
                    : ListView.builder(
                        controller: _scrollController,
                        padding: const EdgeInsets.all(T.s16),
                        itemCount: _messages.length,
                        itemBuilder: (context, index) {
                          final msg = _messages[index];
                          return _MessageBubble(message: msg);
                        },
                      ),
          ),

          // حقل الإرسال
          Container(
            padding: const EdgeInsets.all(T.s12),
            decoration: BoxDecoration(
              color: cs.surface,
              boxShadow: [
                BoxShadow(
                  color: Colors.black.withValues(alpha: 0.05),
                  blurRadius: 8,
                  offset: const Offset(0, -2),
                ),
              ],
            ),
            child: SafeArea(
              child: Row(
                children: [
                  Expanded(
                    child: TripzTextField(
                      controller: _controller,
                      hint: l10n.typeMessage,
                      onSubmitted: (_) => _sendMessage(),
                    ),
                  ),
                  const SizedBox(width: T.s8),
                  IconButton(
                    onPressed: _sending ? null : _sendMessage,
                    icon: _sending
                        ? const SizedBox(
                            width: 20,
                            height: 20,
                            child: CircularProgressIndicator(strokeWidth: 2),
                          )
                        : Icon(Icons.send, color: cs.primary),
                  ),
                ],
              ),
            ),
          ),
        ],
      ),
    );
  }
}

class _MessageBubble extends StatelessWidget {
  final ChatMessageModel message;

  const _MessageBubble({required this.message});

  @override
  Widget build(BuildContext context) {
    final cs = Theme.of(context).colorScheme;

    return Align(
      alignment: message.isMe ? Alignment.centerRight : Alignment.centerLeft,
      child: Container(
        margin: const EdgeInsets.only(bottom: T.s8),
        padding: const EdgeInsets.symmetric(
          horizontal: T.s12,
          vertical: T.s8,
        ),
        constraints: BoxConstraints(
          maxWidth: MediaQuery.of(context).size.width * 0.75,
        ),
        decoration: BoxDecoration(
          color: message.isMe ? cs.primary : cs.surfaceContainerHighest,
          borderRadius: BorderRadius.circular(T.r12).copyWith(
            bottomRight: message.isMe ? const Radius.circular(4) : null,
            bottomLeft: !message.isMe ? const Radius.circular(4) : null,
          ),
        ),
        child: Column(
          crossAxisAlignment: CrossAxisAlignment.start,
          children: [
            Text(
              message.text,
              style: TextStyle(
                color: message.isMe ? cs.onPrimary : cs.onSurface,
              ),
            ),
            const SizedBox(height: 2),
            Text(
              '${message.createdAt.hour.toString().padLeft(2, '0')}:${message.createdAt.minute.toString().padLeft(2, '0')}',
              style: TextStyle(
                fontSize: 10,
                color: message.isMe
                    ? cs.onPrimary.withValues(alpha: 0.7)
                    : cs.onSurfaceVariant,
              ),
            ),
          ],
        ),
      ),
    );
  }
}