// tera-web serves static browser assets and the same-origin REST/stream proxy.
package main

import (
	"context"
	"log"
	"net/http"
	"os"
	"os/signal"
	"strings"
	"syscall"
	"time"

	"tera-clone/services/tera-api/internal/webgateway"
)

func main() {
	listenAddress := webGetenv("TERA_WEB_LISTEN_ADDR", "127.0.0.1:8080")
	handler, err := webgateway.NewHandler(webgateway.Options{
		StaticRoot:      webGetenv("TERA_WEB_STATIC_ROOT", "../../webapp"),
		APIUpstream:     webGetenv("TERA_WEB_API_UPSTREAM", "http://127.0.0.1:8082"),
		SessionUpstream: webGetenv("TERA_WEB_SESSION_UPSTREAM", "http://127.0.0.1:8081"),
	})
	if err != nil {
		log.Fatalf("tera-web setup failed: %v", err)
	}
	server := &http.Server{
		Addr:              listenAddress,
		Handler:           handler,
		ReadHeaderTimeout: 5 * time.Second,
		IdleTimeout:       60 * time.Second,
	}
	log.Printf("tera-web listening on http://%s", listenAddress)
	serverErrors := make(chan error, 1)
	go func() { serverErrors <- server.ListenAndServe() }()
	signalContext, stopSignals := signal.NotifyContext(context.Background(), syscall.SIGINT, syscall.SIGTERM)
	defer stopSignals()
	select {
	case <-signalContext.Done():
		shutdownContext, cancel := context.WithTimeout(context.Background(), 5*time.Second)
		defer cancel()
		if err := server.Shutdown(shutdownContext); err != nil {
			log.Printf("tera-web HTTP shutdown failed: %v", err)
		}
	case err := <-serverErrors:
		if err != nil && err != http.ErrServerClosed {
			log.Fatalf("tera-web failed: %v", err)
		}
	}
}

func webGetenv(key, fallback string) string {
	if value := strings.TrimSpace(os.Getenv(key)); value != "" {
		return value
	}
	return fallback
}