package connect

import (
	"context"
	"fmt"
	"github.com/hashicorp/consul/api"
	"speech-nlu-parse/global"
	"sync"
	"time"

	"google.golang.org/grpc"
	"google.golang.org/grpc/balancer/roundrobin"
	"google.golang.org/grpc/credentials/insecure"
)

// 技能服务连接句柄
var skillConn sync.Map

// 获取GRPC服务连接句柄
func GrpcConn(serverName string) (*grpc.ClientConn, error) {
	if conn, ok := skillConn.Load(serverName); ok {
		return conn.(*grpc.ClientConn), nil
	}

	ctx, cancel := context.WithTimeout(context.Background(), time.Second)
	defer cancel()

	// 通过 Consul 客户端查询服务实例
	consulConfig := api.DefaultConfig()
	consulConfig.Address = global.ServerSetting.ConsulAddr
	client, err := api.NewClient(consulConfig)
	if err != nil {
		return nil, fmt.Errorf("consul client init failed: %v", err)
	}
	entries, _, err := client.Health().Service(serverName, "", true, nil)
	if err != nil {
		global.Logger.Errorf("consul get service %s failed: %v", serverName, err)
		return nil, fmt.Errorf("consul get service %s failed: %v", serverName, err)
	}

	// 健康实例检查
	if len(entries) == 0 {
		return nil, fmt.Errorf("no available instances for service [%s]", serverName)
	}

	// 获取第一个健康实例的地址
	targetAddr := fmt.Sprintf("%s:%d",
		entries[0].Service.Address,
		entries[0].Service.Port)

	fmt.Println(targetAddr)
	opts := []grpc.DialOption{
		//grpc.WithBlock(), //阻塞连接直到成功或超时，存在缺陷
		grpc.WithTransportCredentials(insecure.NewCredentials()),                                     //指定传输层安全性的凭据
		grpc.WithDefaultServiceConfig(fmt.Sprintf(`{"LoadBalancingPolicy": "%s"}`, roundrobin.Name)), // 设置默认的负载均衡策略
	}

	conn, err := grpc.DialContext(ctx, targetAddr, opts...)
	if err != nil {
		return nil, err
	}

	skillConn.Store(serverName, conn)
	return conn, nil
}