# SQS Queue for meteor event processing
resource "aws_sqs_queue" "meteor_processing" {
  name                       = "${local.name_prefix}-processing"
  visibility_timeout_seconds = var.sqs_visibility_timeout_seconds
  message_retention_seconds  = var.sqs_message_retention_seconds
  receive_wait_time_seconds  = 20 # Enable long polling

  # Dead letter queue configuration
  redrive_policy = jsonencode({
    deadLetterTargetArn = aws_sqs_queue.meteor_processing_dlq.arn
    maxReceiveCount     = var.sqs_max_receive_count
  })

  tags = merge(local.common_tags, {
    Name        = "${local.name_prefix}-processing"
    Description = "Queue for processing meteor events"
  })
}

# Dead Letter Queue for failed messages
resource "aws_sqs_queue" "meteor_processing_dlq" {
  name                      = "${local.name_prefix}-processing-dlq"
  message_retention_seconds = var.sqs_message_retention_seconds

  tags = merge(local.common_tags, {
    Name        = "${local.name_prefix}-processing-dlq"
    Description = "Dead letter queue for failed meteor event processing"
  })
}

# SQS Queue policy to allow S3 to send messages
resource "aws_sqs_queue_policy" "meteor_processing_s3" {
  queue_url = aws_sqs_queue.meteor_processing.id

  policy = jsonencode({
    Version = "2012-10-17"
    Statement = [
      {
        Sid    = "AllowS3ToSendMessage"
        Effect = "Allow"
        Principal = {
          Service = "s3.amazonaws.com"
        }
        Action   = "sqs:SendMessage"
        Resource = aws_sqs_queue.meteor_processing.arn
        Condition = {
          ArnEquals = {
            "aws:SourceArn" = aws_s3_bucket.meteor_events.arn
          }
        }
      }
    ]
  })
}

# CloudWatch Alarms for SQS monitoring
resource "aws_cloudwatch_metric_alarm" "sqs_message_age" {
  alarm_name          = "${local.name_prefix}-sqs-message-age"
  comparison_operator = "GreaterThanThreshold"
  evaluation_periods  = "2"
  metric_name         = "ApproximateAgeOfOldestMessage"
  namespace           = "AWS/SQS"
  period              = "300"
  statistic           = "Maximum"
  threshold           = "900" # 15 minutes
  alarm_description   = "This metric monitors message age in SQS queue"
  alarm_actions       = [aws_sns_topic.alerts.arn]

  dimensions = {
    QueueName = aws_sqs_queue.meteor_processing.name
  }

  tags = local.common_tags
}

resource "aws_cloudwatch_metric_alarm" "sqs_dlq_messages" {
  alarm_name          = "${local.name_prefix}-sqs-dlq-messages"
  comparison_operator = "GreaterThanThreshold"
  evaluation_periods  = "1"
  metric_name         = "ApproximateNumberOfVisibleMessages"
  namespace           = "AWS/SQS"
  period              = "300"
  statistic           = "Sum"
  threshold           = "0"
  alarm_description   = "This metric monitors messages in dead letter queue"
  alarm_actions       = [aws_sns_topic.alerts.arn]

  dimensions = {
    QueueName = aws_sqs_queue.meteor_processing_dlq.name
  }

  tags = local.common_tags
}