package scheduler

import (
	"gitlink.org.cn/jcce-pcm/pcm-coordinator/api/internal/types"
	"gorm.io/gorm"
	"math/rand"
	"time"
)

func MatchLabels(dbEngin *gorm.DB, task *types.TaskInfo) ([]int64, error) {
	var ids []int64
	count := 0
	for key := range task.MatchLabels {
		var participantId []int64
		dbEngin.Raw("select participant_id from sc_participant_label_info where `key` = ? and value = ?", key, task.MatchLabels[key]).Scan(&participantId)
		if count == 0 {
			ids = participantId
		}
		if len(participantId) == 0 || len(ids) == 0 {
			return nil, nil
		}
		ids = intersect(ids, participantId)
		count++
	}
	return micsSlice(ids, 1), nil
}

// 求交集
func intersect(slice1, slice2 []int64) []int64 {
	m := make(map[int64]int)
	nn := make([]int64, 0)
	for _, v := range slice1 {
		m[v]++
	}

	for _, v := range slice2 {
		times, _ := m[v]
		if times == 1 {
			nn = append(nn, v)
		}
	}
	return nn
}

func micsSlice(origin []int64, count int) []int64 {
	tmpOrigin := make([]int64, len(origin))
	copy(tmpOrigin, origin)
	//一定要seed
	rand.Seed(time.Now().Unix())
	rand.Shuffle(len(tmpOrigin), func(i int, j int) {
		tmpOrigin[i], tmpOrigin[j] = tmpOrigin[j], tmpOrigin[i]
	})

	result := make([]int64, 0, count)
	for index, value := range tmpOrigin {
		if index == count {
			break
		}
		result = append(result, value)
	}
	return result
}