package agzam.vyatsu.data.local

import androidx.room.Dao
import androidx.room.Insert
import androidx.room.OnConflictStrategy
import androidx.room.Query
import kotlinx.coroutines.flow.Flow

@Dao
interface ScheduleDao {

    @Query("SELECT * FROM schedules WHERE groupId = :groupId ORDER BY weekStart DESC")
    fun observeSchedules(groupId: String): Flow<List<ScheduleEntity>>

    @Query("SELECT * FROM schedules WHERE groupId = :groupId ORDER BY weekStart DESC")
    suspend fun getSchedules(groupId: String): List<ScheduleEntity>

    @Query("DELETE FROM days WHERE scheduleId = :scheduleId")
    suspend fun deleteDaysForSchedule(scheduleId: Long)

    @Insert(onConflict = OnConflictStrategy.ABORT)
    suspend fun insertSchedule(schedule: ScheduleEntity): Long

    @Query("DELETE FROM schedules WHERE groupId = :groupId AND season = :season AND weekStart = :weekStart")
    suspend fun deleteSchedule(groupId: String, season: String, weekStart: Long)

    @Query("DELETE FROM schedules WHERE groupId = :groupId")
    suspend fun deleteAll(groupId: String)

    @Query(
        """
        DELETE FROM schedules
        WHERE groupId = :groupId
          AND id NOT IN (
              SELECT id FROM schedules
              WHERE groupId = :groupId
              ORDER BY weekStart DESC
              LIMIT :keep
          )
        """
    )
    suspend fun trim(groupId: String, keep: Int)

    @Insert(onConflict = OnConflictStrategy.REPLACE)
    suspend fun insertDays(days: List<DayEntity>): List<Long>

    @Insert(onConflict = OnConflictStrategy.REPLACE)
    suspend fun insertLessons(lessons: List<LessonEntity>)

    @Query(
        "SELECT days.* FROM days INNER JOIN schedules ON schedules.id = days.scheduleId " +
            "WHERE schedules.groupId = :groupId ORDER BY days.date"
    )
    suspend fun getDaysForGroup(groupId: String): List<DayEntity>

    @Query(
        "SELECT lessons.* FROM lessons INNER JOIN days ON days.id = lessons.dayId " +
            "INNER JOIN schedules ON schedules.id = days.scheduleId " +
            "WHERE schedules.groupId = :groupId ORDER BY lessons.date, lessons.slotIndex, lessons.lessonIndex"
    )
    suspend fun getLessonsForGroup(groupId: String): List<LessonEntity>

    @Query(
        "SELECT days.* FROM days INNER JOIN schedules ON schedules.id = days.scheduleId " +
            "WHERE schedules.groupId = :groupId ORDER BY days.date"
    )
    fun observeDaysForGroup(groupId: String): Flow<List<DayEntity>>

    @Query(
        "SELECT lessons.* FROM lessons INNER JOIN days ON days.id = lessons.dayId " +
            "INNER JOIN schedules ON schedules.id = days.scheduleId " +
            "WHERE schedules.groupId = :groupId ORDER BY lessons.date, lessons.slotIndex, lessons.lessonIndex"
    )
    fun observeLessonsForGroup(groupId: String): Flow<List<LessonEntity>>
}