<?php

namespace App\Livewire;

use App\Services\LearningAnalyticsService;
use Illuminate\Support\Facades\DB;
use Livewire\Component;

class TeacherDashboard extends Component
{
    public string $teacherId;
    public array $students = [];
    public array $stats = [];
    public bool $loading = false;
    public string $error = '';

    protected LearningAnalyticsService $laService;

    public function mount($teacherId)
    {
        $this->teacherId = $teacherId;
        $this->laService = app(LearningAnalyticsService::class);
        $this->loadDashboardData();
    }

    public function loadDashboardData()
    {
        $this->loading = true;
        $this->error = '';

        try {
            // 获取老师名下的学生
            $this->students = DB::connection('remote_mysql')
                ->table('students as s')
                ->leftJoin('users as u', 's.student_id', '=', 'u.user_id')
                ->where('s.teacher_id', $this->teacherId)
                ->select(
                    's.student_id',
                    's.name as student_name',
                    's.grade',
                    's.class_name',
                    'u.username',
                    'u.email'
                )
                ->get()
                ->map(function($student) {
                    // 获取每个学生的掌握度数据
                    $masteryData = $this->laService->getStudentMastery($student->student_id);
                    
                    $knowledgePoints = $masteryData['data'] ?? [];
                    
                    // 计算统计信息
                    $totalPoints = count($knowledgePoints);
                    $masteredPoints = 0;
                    $avgMastery = 0;
                    $totalAttempts = 0;
                    
                    if (!empty($knowledgePoints)) {
                        $masterySum = 0;
                        foreach ($knowledgePoints as $kp) {
                            $mastery = ($kp['mastery_level'] ?? 0) * 100;
                            $masterySum += $mastery;
                            $totalAttempts += $kp['total_attempts'] ?? 0;
                            
                            if ($mastery >= 80) {
                                $masteredPoints++;
                            }
                        }
                        $avgMastery = round($masterySum / $totalPoints, 1);
                    }

                    return [
                        'student_id' => $student->student_id,
                        'name' => $student->student_name,
                        'grade' => $student->grade,
                        'class' => $student->class_name,
                        'email' => $student->email,
                        'total_knowledge_points' => $totalPoints,
                        'mastered_points' => $masteredPoints,
                        'avg_mastery' => $avgMastery,
                        'total_attempts' => $totalAttempts,
                        'mastery_data' => $knowledgePoints,
                    ];
                })
                ->toArray();

            // 计算总体统计
            $this->calculateStats();

        } catch (\Exception $e) {
            $this->error = '加载数据失败: ' . $e->getMessage();
            \Log::error('TeacherDashboard load error', [
                'teacher_id' => $this->teacherId,
                'error' => $e->getMessage()
            ]);
        } finally {
            $this->loading = false;
        }
    }

    private function calculateStats()
    {
        $totalStudents = count($this->students);
        $totalMasteredPoints = 0;
        $totalAvgMastery = 0;
        $totalAttempts = 0;

        foreach ($this->students as $student) {
            $totalMasteredPoints += $student['mastered_points'];
            $totalAvgMastery += $student['avg_mastery'];
            $totalAttempts += $student['total_attempts'];
        }

        $this->stats = [
            'total_students' => $totalStudents,
            'total_mastered_points' => $totalMasteredPoints,
            'avg_mastery' => $totalStudents > 0 ? round($totalAvgMastery / $totalStudents, 1) : 0,
            'total_attempts' => $totalAttempts,
        ];
    }

    public function render()
    {
        return view('livewire.teacher-dashboard', [
            'stats' => $this->stats,
            'students' => $this->students,
        ]);
    }
}