roomescape-refactored/src/main/kotlin/roomescape/theme/business/ThemeService.kt

package roomescape.theme.business

import com.github.f4b6a3.tsid.TsidFactory
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.common.config.next
import roomescape.theme.exception.ThemeErrorCode
import roomescape.theme.exception.ThemeException
import roomescape.theme.infrastructure.persistence.ThemeEntity
import roomescape.theme.infrastructure.persistence.ThemeRepository
import roomescape.theme.web.ThemeCreateRequest
import roomescape.theme.web.ThemeRetrieveListResponse
import roomescape.theme.web.ThemeRetrieveResponse
import roomescape.theme.web.toResponse
import java.time.LocalDate

private val log = KotlinLogging.logger {}

@Service
class ThemeService(
    private val tsidFactory: TsidFactory,
    private val themeRepository: ThemeRepository,
) {
    @Transactional(readOnly = true)
    fun findById(id: Long): ThemeEntity {
        log.debug { "[ThemeService.findById] 테마 조회 시작: themeId=$id" }

        return themeRepository.findByIdOrNull(id)
            ?.also { log.info { "[ThemeService.findById] 테마 조회 완료: themeId=$id" } }
            ?: run {
                log.warn { "[ThemeService.findById] 테마 조회 실패: themeId=$id" }
                throw ThemeException(ThemeErrorCode.THEME_NOT_FOUND)
            }
    }

    @Transactional(readOnly = true)
    fun findThemes(): ThemeRetrieveListResponse {
        log.debug { "[ThemeService.findThemes] 모든 테마 조회 시작" }

        return themeRepository.findAll()
            .also { log.info { "[ThemeService.findThemes] ${it.size}개의 테마 조회 완료" } }
            .toResponse()
    }

    @Transactional(readOnly = true)
    fun findMostReservedThemes(count: Int): ThemeRetrieveListResponse {
        log.debug { "[ThemeService.findMostReservedThemes] 인기 테마 조회 시작: count=$count" }

        val today = LocalDate.now()
        val startDate = today.minusDays(7)
        val endDate = today.minusDays(1)

        return themeRepository.findPopularThemes(startDate, endDate, count)
            .also { log.info { "[ThemeService.findMostReservedThemes] ${it.size} 개의 인기 테마 조회 완료" } }
            .toResponse()
    }

    @Transactional
    fun createTheme(request: ThemeCreateRequest): ThemeRetrieveResponse {
        log.debug { "[ThemeService.createTheme] 테마 생성 시작: name=${request.name}" }

        if (themeRepository.existsByName(request.name)) {
            log.info { "[ThemeService.createTheme] 테마 생성 실패(이름 중복): name=${request.name}" }
            throw ThemeException(ThemeErrorCode.THEME_NAME_DUPLICATED)
        }

        val theme = ThemeEntity(
            _id = tsidFactory.next(),
            name = request.name,
            description = request.description,
            thumbnail = request.thumbnail
        )
        return themeRepository.save(theme)
            .also { log.info { "[ThemeService.createTheme] 테마 생성 완료: themeId=${it.id}" } }
            .toResponse()
    }

    @Transactional
    fun deleteTheme(id: Long) {
        log.debug { "[ThemeService.deleteTheme] 테마 삭제 시작: themeId=$id" }

        if (themeRepository.isReservedTheme(id)) {
            log.info { "[ThemeService.deleteTheme] 테마 삭제 실패(예약이 있는 테마): themeId=$id" }
            throw ThemeException(ThemeErrorCode.THEME_ALREADY_RESERVED)
        }

        themeRepository.deleteById(id)
            .also { log.info { "[ThemeService.deleteTheme] 테마 삭제 완료: themeId=$id" } }
    }
}