sodalive-backend-spring-boot/src/main/kotlin/kr/co/vividnext/sodalive/fcm/FcmService.kt

package kr.co.vividnext.sodalive.fcm

import com.google.firebase.messaging.AndroidConfig
import com.google.firebase.messaging.ApnsConfig
import com.google.firebase.messaging.Aps
import com.google.firebase.messaging.FirebaseMessaging
import com.google.firebase.messaging.MessagingErrorCode
import com.google.firebase.messaging.MulticastMessage
import com.google.firebase.messaging.Notification
import org.slf4j.LoggerFactory
import org.springframework.beans.factory.annotation.Value
import org.springframework.scheduling.annotation.Async
import org.springframework.stereotype.Service

@Service
class FcmService(
    private val pushTokenService: PushTokenService,
    @Value("\${server.env}")
    private val serverEnv: String
) {
    private val logger = LoggerFactory.getLogger(this::class.java)

    @Async
    fun send(
        tokens: List<String>,
        title: String,
        message: String,
        container: String,
        roomId: Long? = null,
        messageId: Long? = null,
        contentId: Long? = null,
        creatorId: Long? = null,
        auditionId: Long? = null,
        deepLinkValue: FcmDeepLinkValue? = null,
        deepLinkId: Long? = null,
        deepLinkCommentPostId: Long? = null
    ) {
        if (tokens.isEmpty()) return
        logger.info("os: $container")

        var targets = tokens
        val maxAttempts = 3
        var attempt = 1

        while (attempt <= maxAttempts && targets.isNotEmpty()) {
            val multicastMessage = MulticastMessage.builder()
                .addAllTokens(targets)

            multicastMessage.setAndroidConfig(
                AndroidConfig.builder()
                    .setPriority(AndroidConfig.Priority.HIGH)
                    .build()
            )

            multicastMessage.setApnsConfig(
                ApnsConfig.builder()
                    .setAps(
                        Aps.builder()
                            .setSound("default")
                            .build()
                    )
                    .build()
            )

            multicastMessage
                .setNotification(
                    Notification.builder()
                        .setTitle(title)
                        .setBody(message)
                        .build()
                )

            if (roomId != null) {
                multicastMessage.putData("room_id", roomId.toString())
            }

            if (messageId != null) {
                multicastMessage.putData("message_id", messageId.toString())
            }

            if (contentId != null) {
                multicastMessage.putData("content_id", contentId.toString())
            }

            if (creatorId != null) {
                multicastMessage.putData("channel_id", creatorId.toString())
            }

            if (auditionId != null) {
                multicastMessage.putData("audition_id", auditionId.toString())
            }

            val deepLink = createDeepLink(deepLinkValue, deepLinkId, deepLinkCommentPostId)
            if (deepLink != null) {
                multicastMessage.putData("deep_link", deepLink)
            }

            val response = FirebaseMessaging.getInstance().sendEachForMulticast(multicastMessage.build())
            val failedTokens = mutableListOf<String>()

            response.responses.forEachIndexed { index, res ->
                if (!res.isSuccessful) {
                    val exception = res.exception
                    val token = targets[index]

                    if (exception?.messagingErrorCode == MessagingErrorCode.UNREGISTERED) {
                        logger.error("[FCM] ❌ UNREGISTERED → $token")
                        // DB에서 삭제
                        pushTokenService.unregisterInvalidToken(token)
                    } else {
                        logger.error("[FCM] ❌ 실패: $token / ${exception?.messagingErrorCode}")
                        failedTokens.add(token)
                    }
                }
            }

            if (failedTokens.isEmpty()) {
                logger.info("[FCM] ✅ 전체 전송 성공")
                return
            }

            targets = failedTokens
            attempt++
        }

        if (targets.isNotEmpty()) {
            logger.error("[FCM] ❌ 최종 실패 대상 ${targets.size}명 → $targets")
        }
    }

    private fun createDeepLink(
        deepLinkValue: FcmDeepLinkValue?,
        deepLinkId: Long?,
        deepLinkCommentPostId: Long?
    ): String? {
        return buildDeepLink(serverEnv, deepLinkValue, deepLinkId, deepLinkCommentPostId)
    }

    fun sendPointGranted(tokens: List<String>, point: Int) {
        if (tokens.isEmpty()) return
        val data = mapOf(
            "type" to "POINT_GRANTED",
            "point" to point.toString(),
            "message" to "${point}포인트가 지급되었습니다!"
        )

        var targets = tokens
        var attempts = 0
        val maxAttempts = 3

        while (attempts <= maxAttempts && targets.isNotEmpty()) {
            val multicastMessage = MulticastMessage.builder()
                .addAllTokens(targets)
                .putAllData(data)

            multicastMessage.setAndroidConfig(
                AndroidConfig.builder()
                    .setPriority(AndroidConfig.Priority.HIGH)
                    .build()
            )

            multicastMessage.setApnsConfig(
                ApnsConfig.builder()
                    .setAps(
                        Aps.builder()
                            .setSound("default")
                            .build()
                    )
                    .build()
            )

            val response = FirebaseMessaging.getInstance().sendEachForMulticast(multicastMessage.build())
            val failedTokens = mutableListOf<String>()

            response.responses.forEachIndexed { index, res ->
                if (!res.isSuccessful) {
                    val exception = res.exception
                    val token = targets[index]

                    if (exception?.messagingErrorCode == MessagingErrorCode.UNREGISTERED) {
                        logger.error("[FCM] ❌ UNREGISTERED → $token")
                        // DB에서 삭제
                        pushTokenService.unregisterInvalidToken(token)
                    } else {
                        logger.error("[FCM] ❌ 실패: $token / ${exception?.messagingErrorCode}")
                        failedTokens.add(token)
                    }
                }
            }

            if (failedTokens.isEmpty()) {
                logger.info("[FCM] ✅ 전체 전송 성공")
                return
            }

            targets = failedTokens
            attempts++
        }

        if (targets.isNotEmpty()) {
            logger.error("[FCM] ❌ 최종 실패 대상 ${targets.size}명 → $targets")
        }
    }

    companion object {
        fun buildDeepLink(
            serverEnv: String,
            deepLinkValue: FcmDeepLinkValue?,
            deepLinkId: Long?,
            deepLinkCommentPostId: Long? = null
        ): String? {
            if (deepLinkValue == null || deepLinkId == null) {
                return null
            }

            val uriScheme = if (serverEnv.equals("voiceon", ignoreCase = true)) {
                "voiceon"
            } else {
                "voiceon-test"
            }

            val baseDeepLink = "$uriScheme://${deepLinkValue.value}/$deepLinkId"
            if (deepLinkValue == FcmDeepLinkValue.COMMUNITY && deepLinkCommentPostId != null) {
                return "$baseDeepLink?postId=$deepLinkCommentPostId"
            }

            return baseDeepLink
        }
    }
}