<?php
/**
 * GET /api/teacher/classes — alle Klassen der Lehrperson.
 */
declare(strict_types=1);
require_once __DIR__ . '/../../bootstrap.php';

v2_validate_method('GET');
$auth = v2_auth_require('teacher');
$teacherId = (int) ($auth['sub'] ?? 0);

$rows = v2_db_all("
    SELECT c.id, c.name, c.school_year, c.join_code,
           (SELECT COUNT(*) FROM students WHERE class_id = c.id AND deleted_at IS NULL) AS student_count
    FROM classes c
    WHERE c.teacher_id = :tid
    ORDER BY c.created_at DESC
", [':tid' => $teacherId]);

v2_response_ok(['classes' => array_map(fn($r) => [
    'id' => (int) $r['id'],
    'name' => $r['name'],
    'schoolYear' => $r['school_year'],
    'joinCode' => $r['join_code'],
    'studentCount' => (int) $r['student_count'],
], $rows)]);