CourseWork/database/seeders/DatabaseSeeder.php

<?php

namespace Database\Seeders;

use App\Enums\ScoreEnum;
use App\Models\Grade;
use App\Models\Lesson;
use App\Models\Student;
use App\Models\Subject;
use App\Models\Teacher;
use App\Models\User;
use Illuminate\Database\Seeder;

class DatabaseSeeder extends Seeder
{
    /**
     * Seed the application's database.
     */
    public function run(): void
    {
        $namesSubjects = [
            'Русский язык',
            'Математика',
            'Английский язык',
            'Биология',
            'Химия',
            'Литература',
            'География',
            'История',
            'Обществознание',
            'Информатика',
        ];
        $subjects = collect();

        foreach ($namesSubjects as $name) {
            $subjects->push(Subject::factory()->create([
                'name' => $name,
            ]));
        }

        $letterGrades = ['A', 'Б', 'В',];
        $numberGrades = 11;
        $grades = collect();

        while($numberGrades > 0) {
            foreach ($letterGrades as $letter) {
                $grades->push(Grade::factory()->create([
                    'name' => $numberGrades . $letter,
                ]));
            }
            $numberGrades--;
        }
        $teachers = Teacher::factory(15)->create();
        $scores = ScoreEnum::cases();

        $teachers->each(function ($teacher) {
            $user = User::factory()->create();
            $teacher->user()->save($user);
        });

        $teacher = Teacher::factory()->create();
        $teacher->user()->save(User::factory()->create(['email' => 'teacher@mail']));
        $teacher->grades()->attach($grades->pluck('id'));

        $student = Student::factory()->create(['grade_id' => $grades->first()->id]);
        $student->user()->save(User::factory()->create(['email' => 'student@mail']));

        $grade = $student->grade;

        $lessons = collect();
        $subjects->each(function ($item) use ($lessons, $teacher, $student, $grade) {
            $teacher->subjects()->attach($item);
            $grade->subjects()->attach($item);

            $lessons->push(Lesson::factory(5)->create([
                'description' => 'Выполнение задания №3 на 87 стр. учебника',
                'grade_id' => $student->grade_id,
                'subject_id' => $item->id,
                'teacher_id' => $teacher->id,
            ]));
        });


        $grades->each(function ($grade) use ($subjects, $teachers, $scores){
            Student::factory(30)->create([
                'grade_id' => $grade->id,
            ])->each(function ($student) use ($scores) {
                $user = User::factory()->create();
                $student->user()->save($user);
            });
        });

        $grade->students->each(function ($student) use ($grade, $scores) {
            $grade->lessons->each(function ($lesson) use ($student, $scores) {
                $student->lessons()
                    ->syncWithoutDetaching([
                        $lesson->id => ['score' => $scores[array_rand($scores)]]
                    ]);
            });
        });
    }
}