package roomescape.schedule.business

import ScheduleException
import com.github.f4b6a3.tsid.TsidFactory
import io.github.oshai.kotlinlogging.KLogger
import io.github.oshai.kotlinlogging.KotlinLogging
import org.springframework.data.repository.findByIdOrNull
import org.springframework.stereotype.Service
import org.springframework.transaction.annotation.Transactional
import roomescape.admin.business.AdminService
import roomescape.common.config.next
import roomescape.common.dto.AuditInfo
import roomescape.common.dto.OperatorInfo
import roomescape.schedule.business.domain.ScheduleOverview
import roomescape.schedule.exception.ScheduleErrorCode
import roomescape.schedule.infrastructure.persistence.ScheduleEntity
import roomescape.schedule.infrastructure.persistence.ScheduleEntityFactory
import roomescape.schedule.infrastructure.persistence.ScheduleRepository
import roomescape.schedule.infrastructure.persistence.ScheduleStatus
import roomescape.schedule.web.*
import java.time.LocalDate

private val log: KLogger = KotlinLogging.logger {}

/**
 * Structure:
 * - Public: 모두가 접근 가능
 * - User: 회원(로그인된 사용자)가 사용 가능
 * - All-Admin: 모든 관리자가 사용 가능
 * - Store-Admin: 매장 관리자만 사용 가능
 * - Other-Service: 다른 서비스에서 호출하는 메서드
 * - Common: 공통 메서드
 */
@Service
class ScheduleService(
    private val scheduleRepository: ScheduleRepository,
    private val scheduleValidator: ScheduleValidator,
    private val tsidFactory: TsidFactory,
    private val adminService: AdminService
) {
    // ========================================
    // Public (인증 불필요)
    // ========================================
    @Transactional(readOnly = true)
    fun getStoreScheduleByDate(storeId: Long, date: LocalDate): ScheduleWithThemeListResponse {
        log.info { "[ScheduleService.getStoreScheduleByDate] 매장 일정 조회: storeId=${storeId}, date=$date" }

        val schedules: List<ScheduleOverview> =
            scheduleRepository.findStoreSchedulesWithThemeByDate(storeId, date)

        return schedules.toResponse()
            .also {
                log.info { "[ScheduleService.getStoreScheduleByDate] storeId=${storeId}, date=$date 인 ${it.schedules.size}개 일정 조회 완료" }
            }
    }

    // ========================================
    // User (회원 로그인 필요)
    // ========================================
    @Transactional
    fun holdSchedule(id: Long) {
        val schedule: ScheduleEntity = findOrThrow(id)

        if (schedule.status == ScheduleStatus.AVAILABLE) {
            schedule.hold()
            return
        }

        throw ScheduleException(ScheduleErrorCode.SCHEDULE_NOT_AVAILABLE)
    }

    // ========================================
    // All-Admin (본사, 매장 모두 사용가능)
    // ========================================
    @Transactional(readOnly = true)
    fun searchSchedules(storeId: Long, date: LocalDate?, themeId: Long?): AdminScheduleSummaryListResponse {
        log.info { "[ScheduleService.searchSchedules] 일정 검색 시작: storeId=$storeId, date=$date, themeId=$themeId" }

        val searchDate = date ?: LocalDate.now()

        val schedules: List<ScheduleOverview> =
            scheduleRepository.findStoreSchedulesWithThemeByDate(storeId, searchDate)
                .filter { (themeId == null) || (it.themeId == themeId) }
                .sortedBy { it.time }

        return schedules.toAdminSummaryListResponse()
            .also {
                log.info { "[ScheduleService.searchSchedules] ${it.schedules.size} 개의 일정 조회 완료" }
            }
    }

    @Transactional(readOnly = true)
    fun findScheduleAudit(id: Long): AuditInfo {
        log.info { "[ScheduleService.findDetail] 일정 감사 정보 조회 시작: id=$id" }

        val schedule: ScheduleEntity = findOrThrow(id)

        val createdBy: OperatorInfo = adminService.findOperatorOrUnknown(schedule.createdBy)
        val updatedBy: OperatorInfo = adminService.findOperatorOrUnknown(schedule.updatedBy)

        return AuditInfo(schedule.createdAt, createdBy, schedule.updatedAt, updatedBy)
            .also { log.info { "[ScheduleService.findDetail] 일정 감사 정보 조회 완료: id=$id" } }
    }

    // ========================================
    // Store-Admin (매장 관리자 로그인 필요)
    // ========================================
    @Transactional
    fun createSchedule(storeId: Long, request: ScheduleCreateRequest): ScheduleCreateResponse {
        log.info { "[ScheduleService.createSchedule] 일정 생성 시작: storeId=${storeId}, date=${request.date}, time=${request.time}, themeId=${request.themeId}" }

        scheduleValidator.validateCanCreate(storeId, request)

        val schedule = ScheduleEntityFactory.create(
            id = tsidFactory.next(),
            date = request.date,
            time = request.time,
            storeId = storeId,
            themeId = request.themeId
        ).also {
            scheduleRepository.save(it)
        }

        return ScheduleCreateResponse(schedule.id)
            .also {
                log.info { "[ScheduleService.createSchedule] 일정 생성 완료: id=${it.id}" }
            }
    }

    @Transactional
    fun updateSchedule(id: Long, request: ScheduleUpdateRequest) {
        log.info { "[ScheduleService.updateSchedule] 일정 수정 시작: id=$id, request=${request}" }

        if (request.isAllParamsNull()) {
            log.info { "[ScheduleService.updateSchedule] 일정 변경 사항 없음: id=$id" }
            return
        }

        val schedule: ScheduleEntity = findOrThrow(id).also {
            scheduleValidator.validateCanUpdate(it, request)
        }

        schedule.modifyIfNotNull(request.time, request.status).also {
            log.info { "[ScheduleService.updateSchedule] 일정 수정 완료: id=$id, request=${request}" }
        }
    }

    @Transactional
    fun deleteSchedule(id: Long) {
        log.info { "[ScheduleService.deleteSchedule] 일정 삭제 시작: id=$id" }

        val schedule: ScheduleEntity = findOrThrow(id).also {
            scheduleValidator.validateCanDelete(it)
        }

        scheduleRepository.delete(schedule).also {
            log.info { "[ScheduleService.deleteSchedule] 일정 삭제 완료: id=$id" }
        }
    }

    // ========================================
    // Other-Service (API 없이 다른 서비스에서 호출)
    // ========================================
    @Transactional(readOnly = true)
    fun findSummaryById(id: Long): ScheduleSummaryResponse {
        log.info { "[ScheduleService.findDateTimeById] 일정 개요 조회 시작 : id=$id" }

        return findOrThrow(id).toSummaryResponse()
            .also {
                log.info { "[ScheduleService.findDateTimeById] 일정 개요 조회 완료: id=$id" }
            }
    }

    // ========================================
    // Common (공통 메서드)
    // ========================================
    private fun findOrThrow(id: Long): ScheduleEntity {
        log.info { "[ScheduleService.findOrThrow] 일정 조회 시작: id=$id" }

        return scheduleRepository.findByIdOrNull(id)
            ?.also { log.info { "[ScheduleService.findOrThrow] 일정 조회 완료: id=$id" } }
            ?: run {
                log.warn { "[ScheduleService.updateSchedule] 일정 조회 실패. id=$id" }
                throw ScheduleException(ScheduleErrorCode.SCHEDULE_NOT_FOUND)
            }
    }
}