package strategy

import (
	"errors"
	"gitlink.org.cn/jcce-pcm/pcm-coordinator/api/internal/scheduler/entity"
)

type StaticWeightStrategy struct {
	// TODO: add fields

	//每个
	num     int32
	weights []entity.WeightP
}

func (ps *StaticWeightStrategy) Schedule() ([]*AssignedCluster, error) {
	// TODO: implement the scheduling logic	return nil, nil

	if ps.num < 1 {
		return nil, errors.New("numbers must be greater than 0")
	}

	if ps.weights == nil {
		return nil, errors.New("weight must be set")
	}

	var weightSum int32
	weightSum = 0
	for _, w := range ps.weights {
		weightSum += w.Weight
	}

	weightRatio := make([]float64, len(ps.weights))
	for i, w := range ps.weights {
		weightRatio[i] = float64(w.Weight) / float64(weightSum)
	}

	var rest = ps.num
	var results []*AssignedCluster

	for i := 0; i < len(ps.weights); i++ {

		var n = int(float64(ps.num) * weightRatio[i])
		rest -= int32(n)

		cluster := &AssignedCluster{ParticipantId: ps.weights[i].Participant_id, Name: ps.weights[i].Name, Replicas: int32(n)}
		results = append(results, cluster)
	}

	if rest != 0 {
		if rest < 0 { // 如果差值小于0，需要增加某些元素的值
			for i := len(ps.weights) - 1; rest < 0 && i >= 0; i-- {
				if results[i].Replicas < ps.weights[i].Weight {
					results[i].Replicas++
					rest++
				}
			}
		} else {
			for i := len(ps.weights) - 1; rest > 0 && i >= 0; i-- {
				if results[i].Replicas < ps.weights[i].Weight {
					results[i].Replicas--
					rest--
				}
			}
		}
	}

	return results, nil
}