import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:supabase_flutter/supabase_flutter.dart';
import 'package:intl/intl.dart';
import '/core/auth_provider.dart';
import '/models/message.dart';
import '/models/profile.dart';

const _bg   = Color(0xFF0D1117);
const _card = Color(0xFF161B22);
const _blue = Color(0xFF4FC3F7);

class ChatScreen extends ConsumerStatefulWidget {
  final String toUserId; // profiles.id (não auth uid)
  const ChatScreen({super.key, required this.toUserId});
  @override
  ConsumerState<ChatScreen> createState() => _ChatScreenState();
}

class _ChatScreenState extends ConsumerState<ChatScreen> {
  final _msgCtrl    = TextEditingController();
  final _scrollCtrl = ScrollController();
  String? _myProfileId;
  Profile? _otherProfile;
  bool _loadingProfile = true;

  @override
  void initState() {
    super.initState();
    _loadProfiles();
  }

  @override
  void dispose() {
    _msgCtrl.dispose();
    _scrollCtrl.dispose();
    super.dispose();
  }

  Future<void> _loadProfiles() async {
    final sb = Supabase.instance.client;
    final uid = sb.auth.currentUser?.id;
    if (uid == null) return;

    // Buscar o meu profile id
    final me = await sb.from('profiles').select('id').eq('user_id', uid).maybeSingle();
    // Buscar perfil do outro
    final other = await sb.from('profiles').select().eq('id', widget.toUserId).maybeSingle();

    if (mounted) {
      setState(() {
        _myProfileId = me?['id'] as String?;
        _otherProfile = other != null ? Profile.fromMap(other) : null;
        _loadingProfile = false;
      });
    }
    _scrollToBottom();
  }

  Future<void> _send() async {
    final text = _msgCtrl.text.trim();
    if (text.isEmpty || _myProfileId == null) return;
    final sb = Supabase.instance.client;
    _msgCtrl.clear();
    try {
      await sb.from('messages').insert({
        'from_user': _myProfileId,
        'to_user':   widget.toUserId,
        'content':   text,
        'is_read':   false,
      });
      _scrollToBottom();
    } catch (e) {
      if (mounted) {
        ScaffoldMessenger.of(context).showSnackBar(SnackBar(
          content: Text('Erro ao enviar: $e'),
          backgroundColor: Colors.red, behavior: SnackBarBehavior.floating));
      }
    }
  }

  void _scrollToBottom() {
    WidgetsBinding.instance.addPostFrameCallback((_) {
      if (_scrollCtrl.hasClients) {
        _scrollCtrl.animateTo(_scrollCtrl.position.maxScrollExtent,
            duration: const Duration(milliseconds: 300), curve: Curves.easeOut);
      }
    });
  }

  @override
  Widget build(BuildContext context) {
    if (_loadingProfile) {
      return const Scaffold(backgroundColor: _bg,
          body: Center(child: CircularProgressIndicator(color: _blue)));
    }
    if (_myProfileId == null) {
      return const Scaffold(backgroundColor: _bg,
          body: Center(child: Text('Perfil não encontrado.', style: TextStyle(color: Colors.white))));
    }

    final sb = Supabase.instance.client;
    final myId = _myProfileId!;

    return Scaffold(
      backgroundColor: _bg,
      appBar: AppBar(
        backgroundColor: _card,
        elevation: 0,
        title: Row(children: [
          CircleAvatar(
            radius: 18,
            backgroundColor: _blue.withOpacity(0.15),
            backgroundImage: _otherProfile?.avatarUrl != null
                ? NetworkImage(_otherProfile!.avatarUrl!) : null,
            child: _otherProfile?.avatarUrl == null
                ? Text((_otherProfile?.fullName ?? '?')[0].toUpperCase(),
                    style: const TextStyle(color: _blue, fontWeight: FontWeight.bold)) : null,
          ),
          const SizedBox(width: 10),
          Column(crossAxisAlignment: CrossAxisAlignment.start, children: [
            Text(_otherProfile?.fullName ?? 'Utilizador',
                style: const TextStyle(color: Colors.white, fontSize: 14, fontWeight: FontWeight.bold)),
            if (_otherProfile?.role != null)
              Text(_otherProfile!.role, style: const TextStyle(color: Color(0xFF888888), fontSize: 11)),
          ]),
        ]),
      ),
      body: Column(children: [
        Expanded(
          child: StreamBuilder<List<Map<String, dynamic>>>(
            stream: sb.from('messages').stream(primaryKey: ['id']).order('created_at'),
            builder: (context, snapshot) {
              if (snapshot.hasError) {
                return Center(child: Text('Erro: ${snapshot.error}',
                    style: const TextStyle(color: Colors.red)));
              }
              if (!snapshot.hasData) {
                return const Center(child: CircularProgressIndicator(color: _blue));
              }

              final msgs = snapshot.data!
                  .where((m) =>
                    (m['from_user'] == myId && m['to_user'] == widget.toUserId) ||
                    (m['from_user'] == widget.toUserId && m['to_user'] == myId))
                  .map(Message.fromMap)
                  .toList();

              if (msgs.isEmpty) {
                return Center(child: Column(mainAxisAlignment: MainAxisAlignment.center, children: [
                  Icon(Icons.chat_bubble_outline, color: Colors.white.withOpacity(0.15), size: 60),
                  const SizedBox(height: 12),
                  Text('Começa a conversa!',
                      style: TextStyle(color: Colors.white.withOpacity(0.3), fontSize: 14)),
                ]));
              }

              WidgetsBinding.instance.addPostFrameCallback((_) => _scrollToBottom());

              return ListView.builder(
                controller: _scrollCtrl,
                padding: const EdgeInsets.all(16),
                itemCount: msgs.length,
                itemBuilder: (_, i) {
                  final msg = msgs[i];
                  final isMe = msg.fromUser == myId;
                  return _Bubble(msg: msg, isMe: isMe);
                },
              );
            },
          ),
        ),
        // Input
        Container(
          color: _card,
          padding: EdgeInsets.only(
            left: 12, right: 12, top: 10,
            bottom: MediaQuery.of(context).viewInsets.bottom + 10,
          ),
          child: Row(children: [
            Expanded(
              child: TextField(
                controller: _msgCtrl,
                style: const TextStyle(color: Colors.white, fontSize: 14),
                maxLines: 4, minLines: 1,
                textInputAction: TextInputAction.send,
                onSubmitted: (_) => _send(),
                decoration: InputDecoration(
                  hintText: 'Escreve uma mensagem...',
                  hintStyle: TextStyle(color: Colors.white.withOpacity(0.3), fontSize: 13),
                  filled: true, fillColor: Colors.white.withOpacity(0.05),
                  contentPadding: const EdgeInsets.symmetric(horizontal: 16, vertical: 10),
                  border: OutlineInputBorder(borderRadius: BorderRadius.circular(20),
                      borderSide: BorderSide.none),
                ),
              ),
            ),
            const SizedBox(width: 8),
            GestureDetector(
              onTap: _send,
              child: Container(
                width: 44, height: 44,
                decoration: BoxDecoration(
                  gradient: const LinearGradient(colors: [_blue, Color(0xFF0288D1)]),
                  shape: BoxShape.circle,
                  boxShadow: [BoxShadow(color: _blue.withOpacity(0.3), blurRadius: 10)],
                ),
                child: const Icon(Icons.send_rounded, color: Colors.white, size: 20),
              ),
            ),
          ]),
        ),
      ]),
    );
  }
}

class _Bubble extends StatelessWidget {
  final Message msg;
  final bool isMe;
  const _Bubble({required this.msg, required this.isMe});

  @override
  Widget build(BuildContext context) {
    return Padding(
      padding: const EdgeInsets.only(bottom: 8),
      child: Row(
        mainAxisAlignment: isMe ? MainAxisAlignment.end : MainAxisAlignment.start,
        crossAxisAlignment: CrossAxisAlignment.end,
        children: [
          if (!isMe) ...[
            CircleAvatar(radius: 14, backgroundColor: _blue.withOpacity(0.15),
                child: const Icon(Icons.person, color: _blue, size: 14)),
            const SizedBox(width: 6),
          ],
          Flexible(
            child: Container(
              padding: const EdgeInsets.symmetric(horizontal: 14, vertical: 10),
              decoration: BoxDecoration(
                color: isMe ? const Color(0xFF1A4A6A) : _card,
                borderRadius: BorderRadius.only(
                  topLeft: const Radius.circular(16),
                  topRight: const Radius.circular(16),
                  bottomLeft: Radius.circular(isMe ? 16 : 4),
                  bottomRight: Radius.circular(isMe ? 4 : 16),
                ),
                border: Border.all(
                  color: isMe ? _blue.withOpacity(0.3) : Colors.white.withOpacity(0.07)),
              ),
              child: Column(crossAxisAlignment: CrossAxisAlignment.end, children: [
                Text(msg.content,
                    style: const TextStyle(color: Colors.white, fontSize: 14, height: 1.4)),
                const SizedBox(height: 4),
                Text(
                  DateFormat('HH:mm').format(msg.createdAt.toLocal()),
                  style: TextStyle(color: Colors.white.withOpacity(0.35), fontSize: 10),
                ),
              ]),
            ),
          ),
          if (isMe) const SizedBox(width: 4),
        ],
      ),
    );
  }
}