package main

import (
	"context"
	"fmt"
	"github.com/gin-gonic/gin"
	clientv3 "go.etcd.io/etcd/client/v3"
	"google.golang.org/grpc"
	"google.golang.org/grpc/credentials/insecure"
	"google.golang.org/grpc/resolver"
	"net/http"
	config2 "sonet/internal/gateway_http/config"
	"sonet/internal/gateway_http/logic"
	"sonet/pkg/config"
	"sonet/pkg/grpc/discovery"
	"sonet/pkg/grpc/generic"
	"sonet/pkg/utils/shutdown"
)

type GatewayHttpConfig struct {
	Port        int
	IgnoreUrls  []string
	AesTokenKey string
}

func main() {
	appConf := &GatewayHttpConfig{}
	conf := config.LoadConfig(appConf, "cmd/gateway_http")

	// grpc generic client factory
	etcdClient, err := clientv3.New(conf.Etcd)
	if err != nil {
		panic(err)
	}
	etcdResolver := discovery.NewResolver(etcdClient)
	shutdown.AddShutdownHook(etcdResolver.Close)
	resolver.Register(etcdResolver)

	// gin http server
	authFilter, err := config2.NewAuthFilter(appConf.AesTokenKey, appConf.IgnoreUrls)
	if err != nil {
		panic(err)
	}

	server := gin.Default()
	server.Use(authFilter.Filter)

	// postal loadBalancer handler
	postalBalancer := logic.NewPostalBalancer()
	postalBalancer.Init(context.Background())
	server.GET("/api/lb/ws", postalBalancer.Endpoint)

	// grpc services
	grpcGroup := server.Group("/api/svc")
	grpcFactory := generic.NewGpcGenericClientFactory(etcdResolver, grpc.WithTransportCredentials(insecure.NewCredentials()))
	grpcFactory.Init()
	grpcGenericHandler := logic.NewGrpcGenericHandler(grpcFactory)
	grpcGenericHandler.Route(grpcGroup)

	go func() {
		err := server.Run(fmt.Sprintf(":%d", appConf.Port))
		if err != nil {
			panic(err)
		}
	}()

	shutdown.Await()
}

var jsonContentType = []string{"application/json; charset=utf-8"}

type RenderMarshaledJson struct {
	MarshaledJson []byte
}

func (r RenderMarshaledJson) Render(writer http.ResponseWriter) error {
	r.WriteContentType(writer)
	_, err := writer.Write(r.MarshaledJson)
	return err
}

func (r RenderMarshaledJson) WriteContentType(w http.ResponseWriter) {
	header := w.Header()
	header["Content-Type"] = jsonContentType
}