// Изменено: 2026-04-11 — убрано логирование тела сообщения (perf + security)
// SendMessageBatchV1 — пакетная отправка сообщений в очередь тенанта.
package gosqs

import (
	"net/http"
	"strings"
	"time"

	"github.com/google/uuid"

	"shared-sqs/app/interfaces"
	"shared-sqs/app/models"
	"shared-sqs/app/persistence"
	"shared-sqs/app/utils"

	"github.com/gorilla/mux"
	log "github.com/sirupsen/logrus"
)

func SendMessageBatchV1(req *http.Request) (int, interfaces.AbstractResponseBody) {
	requestBody := models.NewSendMessageBatchRequest()
	ok := utils.REQUEST_TRANSFORMER(requestBody, req, false)
	if !ok {
		log.Error("Invalid Request - SendMessageBatchV1")
		return utils.CreateErrorResponseV1("InvalidParameterValue", true)
	}

	t := getTenantFromContext(req)
	if t == nil {
		return utils.CreateErrorResponseV1("InvalidClientTokenId", true)
	}

	queueUrl := requestBody.QueueUrl
	queueName := ""
	if queueUrl == "" {
		vars := mux.Vars(req)
		queueName = vars["queueName"]
	} else {
		uriSegments := strings.Split(queueUrl, "/")
		queueName = uriSegments[len(uriSegments)-1]
	}

	key := tenantQueueKey(t.AccessKey, queueName)

	models.SyncQueues.RLock()
	queue, exists := models.SyncQueues.Queues[key]
	if !exists {
		models.SyncQueues.RUnlock()
		return utils.CreateErrorResponseV1("QueueNotFound", true)
	}
	maxMsgSize := queue.MaximumMessageSize
	currentMsgCount := len(queue.Messages)
	queueIsFIFO := queue.IsFIFO
	models.SyncQueues.RUnlock()

	sendEntries := requestBody.Entries

	if len(sendEntries) == 0 {
		return utils.CreateErrorResponseV1("EmptyBatchRequest", true)
	}

	if len(sendEntries) > 10 {
		return utils.CreateErrorResponseV1("TooManyEntriesInBatchRequest", true)
	}
	ids := map[string]struct{}{}
	for _, v := range sendEntries {
		if _, ok := ids[v.Id]; ok {
			return utils.CreateErrorResponseV1("BatchEntryIdsNotDistinct", true)
		}
		// Валидация длины BatchEntryId (макс 80 chars)
		if err := ValidateBatchEntryID(v.Id); err != nil {
			return utils.CreateErrorResponseV1("InvalidParameterValue", true)
		}
		// Валидация DeduplicationID и GroupID (макс 128 chars)
		if err := ValidateDeduplicationID(v.MessageDeduplicationId); err != nil {
			return utils.CreateErrorResponseV1("InvalidParameterValue", true)
		}
		if err := ValidateGroupID(v.MessageGroupId); err != nil {
			return utils.CreateErrorResponseV1("InvalidParameterValue", true)
		}
		ids[v.Id] = struct{}{}
	}

	sentEntries := make([]models.SendMessageBatchResultEntry, 0)
	log.Debugf("Batch sending to Queue: %s (tenant: %s)", queueName, t.ID)

	// Fix #2: проверяем размер каждого сообщения в batch (Critical — batch size bypass)
	if maxMsgSize <= 0 {
		maxMsgSize = MaxMessageSizeDefault
	}
	for _, entry := range sendEntries {
		if len(entry.MessageBody) > maxMsgSize {
			return utils.CreateErrorResponseV1("MessageTooBig", true)
		}
		// Валидация количества message attributes (макс 10 по AWS)
		if len(entry.MessageAttributes) > MaxMessageAttributes {
			return utils.CreateErrorResponseV1("InvalidParameterValue", true)
		}
	}

	// Fix #11: лимит сообщений в очереди — защита от OOM
	if currentMsgCount+len(sendEntries) > MaxMessagesForQueue(queueIsFIFO) {
		return utils.CreateErrorResponseV1("OverLimit", true)
	}

	models.SyncQueues.Lock()
	// Перепроверка под Lock: очередь могла быть удалена между RLock-проверкой
	// выше и захватом Lock (иначе nil-pointer deref).
	queue = models.SyncQueues.Queues[key]
	if queue == nil {
		models.SyncQueues.Unlock()
		return utils.CreateErrorResponseV1("QueueNotFound", true)
	}
	newMsgs := make([]models.SqsMessage, 0, len(sendEntries))
	for _, sendEntry := range sendEntries {
		msg := models.SqsMessage{MessageBody: sendEntry.MessageBody}
		if len(sendEntry.MessageAttributes) > 0 {
			msg.MessageAttributes = sendEntry.MessageAttributes
			msg.MD5OfMessageAttributes = utils.HashAttributes(sendEntry.MessageAttributes)
		}
		msg.MD5OfMessageBody = utils.GetMD5Hash(sendEntry.MessageBody)
		msg.GroupID = sendEntry.MessageGroupId
		msg.DeduplicationID = sendEntry.MessageDeduplicationId
		msg.Uuid = uuid.NewString()
		msg.SentTime = time.Now()

		fifoSeqNumber := ""
		if queue.IsFIFO {
			fifoSeqNumber = queue.NextSequenceNumber(sendEntry.MessageGroupId)
		}
		if !queue.IsDuplicate(sendEntry.MessageDeduplicationId) {
			queue.Messages = append(queue.Messages, msg)
		} else {
			log.Debugf("Duplicate deduplicationId [%s] in queue [%s]", sendEntry.MessageDeduplicationId, queueName)
		}
		queue.InitDuplicatation(sendEntry.MessageDeduplicationId)

		sentEntries = append(sentEntries, models.SendMessageBatchResultEntry{
			Id:                     sendEntry.Id,
			MessageId:              msg.Uuid,
			MD5OfMessageBody:       msg.MD5OfMessageBody,
			MD5OfMessageAttributes: msg.MD5OfMessageAttributes,
			SequenceNumber:         fifoSeqNumber,
		})
		newMsgs = append(newMsgs, msg)
		// Логируем только метаданные — тело сообщения не логируется (perf + security)
		log.Debugf("Queue: %s, MessageId: %s, Size: %d bytes", queueName, msg.Uuid, len(sendEntry.MessageBody))
	}
	// Персистим новые сообщения отдельно — O(batch_size*msg_size) вместо O(N*msg_size)
	persistence.SaveMessages(key, newMsgs)
	// Метаданные очереди (FIFO state, duplicates) — без Messages
	persistence.SaveQueue(key, queue)
	models.SyncQueues.Unlock()

	respStruct := models.SendMessageBatchResponse{
		Xmlns:    models.BaseXmlns,
		Result:   models.SendMessageBatchResult{Entry: sentEntries},
		Metadata: models.BaseResponseMetadata,
	}

	return http.StatusOK, respStruct
}