CourseWork/app/Services/TeacherService.php

<?php

namespace App\Services;

use App\Models\Student;
use App\Models\Subject;
use App\Models\Teacher;
use App\Models\User;
use Illuminate\Pagination\LengthAwarePaginator;
use Illuminate\Support\Facades\Auth;

class TeacherService
{
    public function create(array $data): Teacher
    {
        $user = User::create([
            'email' => $data['email'],
            'password' => $data['password'],
        ]);
        $teacher = Teacher::create([
            'name' => $data['name'],
            'last_name' => $data['last_name'],
            'middle_name' => $data['middle_name'],
            'birthday' => $data['birthday'],
        ]);
        $teacher->user()->save($user);

        return $teacher;
    }

    public function update(Teacher $teacher, array $data): Teacher
    {
        $teacher->user()->update([
            'email' => $data['email'],
            'password' => $data['password'],
        ]);

        $teacher->update([
            'name' => $data['name'],
            'last_name' => $data['last_name'],
            'middle_name' => $data['middle_name'],
            'birthday' => $data['birthday'],
        ]);

        return $teacher;
    }

    public function delete(Teacher $teacher): void
    {
        $teacher->user()->delete();
        $teacher->delete();
    }

    public function getTeachers()
    {
        if (Auth::user()->userable_type == Student::class) {
            return Teacher::join('grade_teacher', 'teachers.id', '=', 'grade_teacher.teacher_id')
                ->where('grade_id', Auth::user()->userable->grade_id)
                ->filter()
                ->paginate(5)
                ->withQueryString();
        }

        return Teacher::filter()->paginate(5)->withQueryString();
    }

    public function getSubjects(Teacher $teacher)
    {
        if (Auth::user()->userable_type == Student::class) {
            return Subject::join('subject_teacher', 'subject_teacher.subject_id', '=', 'subjects.id')
                ->join('grade_subject', 'grade_subject.subject_id', '=', 'subjects.id')
                ->where('grade_subject.grade_id', Auth::user()->userable->grade_id)
                ->where('subject_teacher.teacher_id', $teacher->id)
                ->get();
        }

        return $teacher->subjects;
    }
}