import 'package:flutter/material.dart';
import 'package:cloud_firestore/cloud_firestore.dart';

import '../../../../core/theme/app_theme_extension.dart';
import '../../../../core/services/auth_service.dart';
import '../../../../core/services/gamification_service.dart';
import '../../../../core/models/class_stats.dart';

/// Analytics preview section for teacher dashboard
class TeacherAnalyticsPreviewWidget extends StatefulWidget {
  const TeacherAnalyticsPreviewWidget({super.key});

  @override
  State<TeacherAnalyticsPreviewWidget> createState() => _TeacherAnalyticsPreviewWidgetState();
}

class _TeacherAnalyticsPreviewWidgetState extends State<TeacherAnalyticsPreviewWidget> {
  List<StudentRanking> _topStudents = [];
  bool _loading = true;

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

  Future<void> _loadTopStudents() async {
    try {
      final user = AuthService.currentUser;
      if (user == null) return;

      // Obter turmas do professor
      final classesSnapshot = await FirebaseFirestore.instance
          .collection('classes')
          .where('teacherId', isEqualTo: user.uid)
          .get();

      List<StudentRanking> allStudents = [];
      
      // Buscar ranking de cada turma
      for (final classDoc in classesSnapshot.docs) {
        final classId = classDoc.id;
        // Forçar atualização para obter dados mais recentes
        final rankings = await GamificationService.getClassRanking(classId);
        allStudents.addAll(rankings);
      }

      // Ordenar por score e pegar os top 4
      allStudents.sort((a, b) => b.overallScore.compareTo(a.overallScore));
      final top4 = allStudents.take(4).toList();

      if (mounted) {
        setState(() {
          _topStudents = top4;
          _loading = false;
        });
      }
    } catch (e) {
      print('Error loading top students: $e');
      if (mounted) {
        setState(() {
          _loading = false;
        });
      }
    }
  }

  @override
  Widget build(BuildContext context) {
    final user = AuthService.currentUser;
    final userName = user?.displayName ?? 'Professor';
    final userEmail = user?.email ?? '';

    return Container(
      margin: const EdgeInsets.only(top: 24),
      padding: const EdgeInsets.all(20),
      decoration: BoxDecoration(
        color: Theme.of(context).colorScheme.surface,
        borderRadius: BorderRadius.circular(16),
        border: Border.all(
          color: Theme.of(context).colorScheme.outline.withOpacity(0.2),
        ),
        boxShadow: [
          BoxShadow(
            color: Theme.of(context).colorScheme.shadow.withOpacity(0.05),
            blurRadius: 10,
            offset: const Offset(0, 4),
          ),
        ],
      ),
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          // Profile Header
          Row(
            children: [
              Container(
                width: 48,
                height: 48,
                decoration: BoxDecoration(
                  gradient: LinearGradient(
                    colors: [
                      AppThemeExtras.of(context).actionCardGradientStart,
                      AppThemeExtras.of(context).actionCardGradientEnd,
                    ],
                  ),
                  borderRadius: BorderRadius.circular(24),
                ),
                child: const Icon(Icons.school, color: Colors.white, size: 24),
              ),
              const SizedBox(width: 16),
              Expanded(
                child: Column(
                  crossAxisAlignment: CrossAxisAlignment.start,
                  children: [
                    Text(
                      userName,
                      style: TextStyle(
                        color: Theme.of(context).colorScheme.onSurface,
                        fontSize: 18,
                        fontWeight: FontWeight.bold,
                      ),
                    ),
                    const SizedBox(height: 2),
                    SingleChildScrollView(
                      scrollDirection: Axis.horizontal,
                      child: Row(
                        mainAxisSize: MainAxisSize.min,
                        children: [
                          Text(
                            userEmail,
                            style: TextStyle(
                              color: Theme.of(
                                context,
                              ).colorScheme.onSurfaceVariant,
                              fontSize: 14,
                            ),
                          ),
                          if (userEmail.length > 20) ...[
                            const SizedBox(width: 8),
                            Icon(
                              Icons.more_horiz,
                              color: Theme.of(
                                context,
                              ).colorScheme.onSurfaceVariant,
                              size: 16,
                            ),
                          ],
                        ],
                      ),
                    ),
                  ],
                ),
              ),
              Container(
                padding: const EdgeInsets.all(8),
                decoration: BoxDecoration(
                  color: Theme.of(
                    context,
                  ).colorScheme.secondary.withOpacity(0.1),
                  borderRadius: BorderRadius.circular(8),
                ),
                child: Icon(
                  Icons.settings,
                  color: Theme.of(context).colorScheme.secondary,
                  size: 20,
                ),
              ),
            ],
          ),
          const SizedBox(height: 20),

          // Quick Stats Row
          Row(
            children: [
              _buildQuickStat(
                icon: Icons.check_circle,
                label: 'Alunos Ativos',
                value: '18/24',
                color: Theme.of(context).colorScheme.primary,
              ),
              const SizedBox(width: 12),
              _buildQuickStat(
                icon: Icons.warning_amber,
                label: 'Precisam Apoio',
                value: '3',
                color: Theme.of(context).colorScheme.secondary,
              ),
              const SizedBox(width: 12),
              _buildQuickStat(
                icon: Icons.emoji_events,
                label: 'Média Disciplina',
                value: '72%',
                color: Theme.of(context).colorScheme.primary.withOpacity(0.8),
              ),
            ],
          ),
          const SizedBox(height: 20),

          // Top Performing Students Preview
          Row(
            children: [
              Icon(
                Icons.leaderboard,
                color: Theme.of(context).colorScheme.secondary,
                size: 20,
              ),
              const SizedBox(width: 8),
              Text(
                'Melhores Desempenhos',
                style: TextStyle(
                  color: Theme.of(context).colorScheme.onSurface,
                  fontSize: 16,
                  fontWeight: FontWeight.bold,
                ),
              ),
            ],
          ),
          const SizedBox(height: 12),

          // Student List Preview
          if (_loading)
            const Center(child: CircularProgressIndicator())
          else if (_topStudents.isEmpty)
            const Center(
              child: Text(
                'Nenhum aluno encontrado',
                style: TextStyle(fontSize: 14),
              ),
            )
          else
            ..._topStudents.asMap().entries.map((entry) {
              final index = entry.key;
              final student = entry.value;
              final color = _getStudentColor(context, index);
              
              return Padding(
                padding: const EdgeInsets.only(bottom: 8),
                child: _buildStudentPerformanceItem(
                  context,
                  student.studentName,
                  student.overallScore.toInt(),
                  color,
                ),
              );
            }).toList(),

          const SizedBox(height: 20),

          // Content Quality Alert
          Container(
            padding: const EdgeInsets.all(16),
            decoration: BoxDecoration(
              color: Theme.of(context).colorScheme.surfaceContainerHighest,
              borderRadius: BorderRadius.circular(12),
              border: Border.all(
                color: Theme.of(context).colorScheme.outline.withOpacity(0.2),
              ),
            ),
            child: Row(
              children: [
                Icon(
                  Icons.info_outline,
                  color: Theme.of(context).colorScheme.primary,
                  size: 20,
                ),
                const SizedBox(width: 12),
                Expanded(
                  child: Column(
                    crossAxisAlignment: CrossAxisAlignment.start,
                    children: [
                      Text(
                        'Qualidade do Conteúdo',
                        style: TextStyle(
                          color: Theme.of(context).colorScheme.onSurface,
                          fontSize: 14,
                          fontWeight: FontWeight.bold,
                        ),
                      ),
                      const SizedBox(height: 2),
                      Text(
                        '12 conteúdos verificados • 2 pendentes de revisão',
                        style: TextStyle(
                          color: Theme.of(context).colorScheme.onSurfaceVariant,
                          fontSize: 12,
                        ),
                      ),
                    ],
                  ),
                ),
              ],
            ),
          ),
        ],
      ),
    );
  }

  Widget _buildQuickStat({
    required IconData icon,
    required String label,
    required String value,
    required Color color,
  }) {
    return Expanded(
      child: Container(
        padding: const EdgeInsets.all(12),
        decoration: BoxDecoration(
          color: color.withOpacity(0.1),
          borderRadius: BorderRadius.circular(12),
          border: Border.all(color: color.withOpacity(0.3), width: 1),
        ),
        child: Column(
          children: [
            Icon(icon, color: color, size: 20),
            const SizedBox(height: 6),
            Text(
              value,
              style: TextStyle(
                color: color,
                fontSize: 16,
                fontWeight: FontWeight.bold,
              ),
            ),
            const SizedBox(height: 2),
            Text(
              label,
              style: TextStyle(color: color.withOpacity(0.8), fontSize: 10),
              textAlign: TextAlign.center,
              maxLines: 3,
            ),
          ],
        ),
      ),
    );
  }

  Color _getStudentColor(BuildContext context, int index) {
    final colors = [
      Theme.of(context).colorScheme.tertiary,
      Theme.of(context).colorScheme.primary,
      Theme.of(context).colorScheme.primary,
      Theme.of(context).colorScheme.secondary,
    ];
    return colors[index % colors.length];
  }

  Widget _buildStudentPerformanceItem(
    BuildContext context,
    String name,
    int score,
    Color color,
  ) {
    return Row(
      children: [
        Container(
          width: 32,
          height: 32,
          decoration: BoxDecoration(
            color: color.withOpacity(0.1),
            borderRadius: BorderRadius.circular(16),
          ),
          child: Center(
            child: Text(
              name.split(' ').map((n) => n[0]).take(2).join(),
              style: TextStyle(
                color: color,
                fontSize: 12,
                fontWeight: FontWeight.bold,
              ),
            ),
          ),
        ),
        const SizedBox(width: 12),
        Expanded(
          child: Text(
            name,
            style: TextStyle(
              color: Theme.of(context).colorScheme.onSurfaceVariant,
              fontSize: 14,
            ),
          ),
        ),
        Container(
          padding: const EdgeInsets.symmetric(horizontal: 8, vertical: 4),
          decoration: BoxDecoration(
            color: color.withOpacity(0.1),
            borderRadius: BorderRadius.circular(8),
          ),
          child: Text(
            '$score%',
            style: TextStyle(
              color: color,
              fontSize: 12,
              fontWeight: FontWeight.bold,
            ),
          ),
        ),
      ],
    );
  }
}