package gateway

import (
	"context"
	"fmt"
	"log"
	"net"
	"net/http"
	"time"

	authPb "datarush/pkg/api/auth"

	"github.com/grpc-ecosystem/grpc-gateway/v2/runtime"
	"google.golang.org/grpc"
	"google.golang.org/grpc/credentials/insecure"
)

const (
	httpReadTimeout  = 10 * time.Second
	httpWriteTimeout = 10 * time.Second
	httpIdleTimeout  = 60 * time.Second
)

func StartGateway(grpcPort, httpPort int, authGrpcAddr string) error {
	ctx := context.Background()
	ctx, cancel := context.WithCancel(ctx)
	defer cancel()

	gwmux := runtime.NewServeMux()
	opts := []grpc.DialOption{grpc.WithTransportCredentials(insecure.NewCredentials())}

	// Register auth service
	if err := authPb.RegisterAuthServiceHandlerFromEndpoint(ctx, gwmux, authGrpcAddr, opts); err != nil {
		return fmt.Errorf("failed to register auth service: %w", err)
	}

	srv := &http.Server{
		Addr:         fmt.Sprintf(":%d", httpPort),
		Handler:      gwmux,
		ReadTimeout:  httpReadTimeout,
		WriteTimeout: httpWriteTimeout,
		IdleTimeout:  httpIdleTimeout,
	}

	log.Printf("starting gRPC-Gateway on port %d", httpPort)
	return srv.ListenAndServe()
}

func GetGRPCListener(port int) (net.Listener, error) {
	return net.Listen("tcp", fmt.Sprintf(":%d", port))
}