// Package balance...
//
// Description : balance...
//
// Author : go_developer@163.com<白茶清欢>
//
// Date : 2021-11-22 6:27 下午
package balance

import (
	"errors"
	"net/http"
	"sync"

	"git.zhangdeman.cn/zhangdeman/gopkg/util"

	"git.zhangdeman.cn/zhangdeman/gopkg/balance/define"
)

// NewRandom ...
//
// Author : go_developer@163.com<白茶清欢>
//
// Date : 6:29 下午 2021/11/22
func NewRandom(severList []*define.ServerNode) (IBalance, error) {
	if nil == severList || len(severList) == 0 {
		return nil, errors.New("sever list is empty")
	}
	return &Random{
		base{
			lock:      &sync.RWMutex{},
			severList: make([]*define.ServerNode, 0),
		},
	}, nil
}

// Random 随机负载均衡
//
// Author : go_developer@163.com<白茶清欢>
//
// Date : 6:27 下午 2021/11/22
type Random struct {
	base
}

// GetServerNode ...
//
// Author : go_developer@163.com<白茶清欢>
//
// Date : 6:31 下午 2021/11/22
func (r *Random) GetServerNode(req *http.Request) (*define.ServerNode, error) {
	r.RLock()
	defer r.RUnlock()
	if len(r.severList) == 0 {
		return nil, errors.New("sever list is empty")
	}
	randomID := util.GetHashID(util.GenRandomString("", 128)) % uint64(len(r.severList))
	return r.severList[int(randomID)], nil
}