func AllocateByAveragely()

in consumer/strategy.go [46:100]
50 lines of code
13 McCabe index (conditional complexity)

func AllocateByAveragely(consumerGroup, currentCID string, mqAll []*primitive.MessageQueue,
	cidAll []string) []*primitive.MessageQueue {
	if currentCID == "" || len(mqAll) == 0 || len(cidAll) == 0 {
		return nil
	}

	var (
		find  bool
		index int
	)
	for idx := range cidAll {
		if cidAll[idx] == currentCID {
			find = true
			index = idx
			break
		}
	}
	if !find {
		rlog.Warning("[BUG] ConsumerId not in cidAll", map[string]interface{}{
			rlog.LogKeyConsumerGroup: consumerGroup,
			"consumerId":             currentCID,
			"cidAll":                 cidAll,
		})
		return nil
	}

	mqSize := len(mqAll)
	cidSize := len(cidAll)
	mod := mqSize % cidSize

	var averageSize int
	if mqSize <= cidSize {
		averageSize = 1
	} else {
		if mod > 0 && index < mod {
			averageSize = mqSize/cidSize + 1
		} else {
			averageSize = mqSize / cidSize
		}
	}

	var startIndex int
	if mod > 0 && index < mod {
		startIndex = index * averageSize
	} else {
		startIndex = index*averageSize + mod
	}

	num := utils.MinInt(averageSize, mqSize-startIndex)
	result := make([]*primitive.MessageQueue, 0)
	for i := 0; i < num; i++ {
		result = append(result, mqAll[(startIndex+i)%mqSize])
	}
	return result
}