package ru.mcs.diary.group;

import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.data.jpa.repository.Query;
import org.springframework.data.repository.query.Param;
import org.springframework.stereotype.Repository;

import java.util.List;
import java.util.Optional;

@Repository
public interface GroupRepository extends JpaRepository<StudyGroup, Long> {

    List<StudyGroup> findAllByTeacherIdOrderByNameAsc(Long teacherId);

    @Query("SELECT g FROM StudyGroup g LEFT JOIN FETCH g.subject WHERE g.teacher.id = :teacherId ORDER BY g.name")
    List<StudyGroup> findAllByTeacherIdWithSubject(@Param("teacherId") Long teacherId);

    Optional<StudyGroup> findByIdAndTeacherId(Long id, Long teacherId);

    @Query("SELECT g FROM StudyGroup g LEFT JOIN FETCH g.subject LEFT JOIN FETCH g.students WHERE g.id = :id AND g.teacher.id = :teacherId")
    Optional<StudyGroup> findByIdWithStudents(@Param("id") Long id, @Param("teacherId") Long teacherId);

    long countByTeacherId(Long teacherId);
}