package flow

import (
	"context"
	"fmt"
	"gitee.com/os-lee/easy-paas/common"
	"github.com/go-redis/redis/v8"
	"strconv"
	"sync"
	"time"
)

// QpsCounterHandler QPS计算器
var (
	QpsCounterHandler *QpsCounter
)

func init() {
	QpsCounterHandler = newQpsCounter()
}

type QpsCounter struct {
	QpsCounterMap sync.Map
}

func newQpsCounter() *QpsCounter {
	return &QpsCounter{
		QpsCounterMap: sync.Map{},
	}
}

type QpsCounterItem struct {
	RedisCli    *redis.Client
	serviceName string
	Requests    int64     // 请求计数
	StartTime   time.Time // 开始时间
}

func newQpsCounterItem(serviceName string, redisCli *redis.Client) *QpsCounterItem {
	return &QpsCounterItem{
		RedisCli:    redisCli,
		serviceName: serviceName,
		Requests:    0,
		StartTime:   time.Now(),
	}
}

func (qc *QpsCounter) GetQpsCounterItem(serviceName string, redisCli *redis.Client) *QpsCounterItem {
	if value, ok := qc.QpsCounterMap.Load(serviceName); ok {
		return value.(*QpsCounterItem)
	}
	item := newQpsCounterItem(serviceName, redisCli)
	qc.QpsCounterMap.Store(serviceName, item)
	return item
}

func (qci *QpsCounterItem) WriteQPS(ctx context.Context, qps float64) error {
	// 写入网关当前QPS
	gwKey := fmt.Sprintf("%s_%s", common.ReqCounterByService, common.EasyGatewayReq)
	err := qci.RedisCli.Set(ctx, gwKey,
		strconv.FormatFloat(qps, 'f', 2, 64), 5*time.Second).Err()
	// 写入各业务QPS
	svcKey := fmt.Sprintf("%s_%s", common.ReqCounterByService, qci.serviceName)
	err = qci.RedisCli.Set(ctx, svcKey,
		strconv.FormatFloat(qps, 'f', 2, 64), 5*time.Second).Err()
	return err
}

func (qci *QpsCounterItem) GetQps(ctx context.Context) (string, error) {
	key := fmt.Sprintf("%s_%s", common.ReqCounterByService, qci.serviceName)
	return qci.RedisCli.Get(ctx, key).Result()
}