package locator

import (
	"context"
	"fmt"
	"git.hlsq.asia/alex/service-common/db/redis"
	"git.hlsq.asia/alex/service-common/log"
)

// 玩家定位器

const (
	KeyGatewayInfo       = "gateway:info:%v"
	HFieldInfoGatewaySID = "gateway_sid_%v"
)

var (
	scriptBindGatewaySha1 string
	scriptBindGateway     = `
local gateway_key = KEYS[1]
local field_key = ARGV[1]
local new_sid = ARGV[2]

local existing_sid = redis.call("HGET", gateway_key, field_key)
if existing_sid then
    return 0
end

redis.call("HSET", gateway_key, field_key, new_sid)
return 1
`
)

func NewLocator(ctx context.Context, usn int64, platform int32) *Locator {
	return &Locator{
		ctx:      ctx,
		usn:      usn,
		platform: platform,
	}
}

type Locator struct {
	ctx      context.Context
	usn      int64
	platform int32
}

// BindGateway 绑定网关
func (l *Locator) BindGateway(gatewaySID int64) bool {
	if scriptBindGatewaySha1 == "" {
		scriptBindGatewaySha1 = redis.GetClient().ScriptLoad(l.ctx, scriptBindGateway).Val()
	}

	result, err := redis.GetClient().EvalSha(
		l.ctx,
		scriptBindGatewaySha1,
		[]string{fmt.Sprintf(KeyGatewayInfo, l.usn)},
		fmt.Sprintf(HFieldInfoGatewaySID, l.platform),
		gatewaySID,
	).Int64()
	if err != nil {
		return false
	}
	if result == 0 {
		return false
	}
	return true
}

// UnbindGateway 解绑网关
func (l *Locator) UnbindGateway() {
	err := redis.GetClient().HDel(l.ctx, fmt.Sprintf(KeyGatewayInfo, l.usn), fmt.Sprintf(HFieldInfoGatewaySID, l.platform)).Err()
	if err != nil {
		log.Errorf("UnbindGateway Failed %v-%v, err: %v", l.usn, l.platform, err)
	}
}

// LocateGateway 定位网关
func (l *Locator) LocateGateway() int64 {
	sid, _ := redis.GetClient().HGet(l.ctx, fmt.Sprintf(KeyGatewayInfo, l.usn), fmt.Sprintf(HFieldInfoGatewaySID, l.platform)).Int64()
	return sid
}