package main

import (
	"context"
	"fmt"
	"log"
	"net/http"
	"os"
	"os/signal"
	"syscall"

	"k8s.io/client-go/dynamic"
	"k8s.io/client-go/rest"

	"forgejo.riotpiao.com/rock/homelab-frontend/internal/config"
	"forgejo.riotpiao.com/rock/homelab-frontend/internal/proxy"
	"forgejo.riotpiao.com/rock/homelab-frontend/internal/server"
	"forgejo.riotpiao.com/rock/homelab-frontend/internal/serviceadapter"
	"forgejo.riotpiao.com/rock/homelab-frontend/internal/temporal"
)

func main() {
	// Load configuration
	cfg, err := config.Load()
	if err != nil {
		fmt.Fprintf(os.Stderr, "failed to load config: %v\n", err)
		os.Exit(1)
	}

	// Determine if auth is enabled by checking if any route requires it
	authEnabled := false
	for _, route := range cfg.Routes {
		if route.Upstream.AuthRequired {
			authEnabled = true
			break
		}
	}

	// Create the reverse proxy handler that routes requests based on configuration
	upstreamHandler := proxy.New(cfg)

	// Create the Temporal workflow handler
	// Temporal server address can be configured via environment variable
	temporalHostPort := os.Getenv("TEMPORAL_HOST_PORT")
	if temporalHostPort == "" {
		temporalHostPort = "localhost:7233"
	}
	log.Printf("Temporal server: %s", temporalHostPort)
	temporalHandler := temporal.NewHandler(temporalHostPort)

	// Create server with health checker
	srv := server.New(cfg.ListenAddr, cfg.ShutdownTimeout, nil)
	
	// Initialize health checker with config validity and auth status
	healthChecker := server.NewHealthChecker(true, authEnabled)
	srv.SetHealthChecker(healthChecker)
	
	// Create ServiceAdapter registry and dispatcher (phase 8)
	registry := serviceadapter.NewRegistry(nil) // nil uses default logger
	dispatcher := serviceadapter.NewDispatcher(registry)

	// Start ServiceAdapter informer to watch CRDs (8.1 integration)
	var informerMgr *serviceadapter.InformerManager
	if kubeConfig, err := rest.InClusterConfig(); err == nil {
		if dynamicClient, err := dynamic.NewForConfig(kubeConfig); err == nil {
			if informer, err := serviceadapter.NewInformerManager(dynamicClient, registry, "api"); err == nil {
				informerMgr = informer
				if err := informer.Start(context.Background()); err != nil {
					log.Printf("warning: failed to start ServiceAdapter informer: %v", err)
				}
			} else {
				log.Printf("warning: failed to create ServiceAdapter informer: %v", err)
			}
		} else {
			log.Printf("warning: failed to create dynamic client: %v", err)
		}
	} else {
		log.Printf("warning: not running in cluster, ServiceAdapter CRDs won't be watched")
	}

	// Create router that handles health endpoints, X-Service (ServiceAdapter) routing,
	// temporal endpoints, and passes others to upstream handler
	router := server.NewRouter(healthChecker, dispatcher, temporalHandler, upstreamHandler)
	srv.SetHandler(router)

	// Set up signal handling
	sigChan := make(chan os.Signal, 1)
	signal.Notify(sigChan, syscall.SIGTERM, syscall.SIGINT)

	// Start server in a goroutine
	var serverErr error
	go func() {
		log.Printf("gateway listening on %s", srv.Addr())
		serverErr = srv.ListenAndServe()
		if serverErr != nil && serverErr != http.ErrServerClosed {
			log.Printf("server error: %v", serverErr)
		}
	}()

	// Wait for shutdown signal
	sig := <-sigChan
	log.Printf("received signal: %v", sig)

	// Stop informer if running
	if informerMgr != nil {
		informerMgr.Stop()
	}

	// Gracefully shutdown the server
	if err := srv.Shutdown(context.Background()); err != nil {
		fmt.Fprintf(os.Stderr, "shutdown error: %v\n", err)
		os.Exit(1)
	}

	log.Printf("gateway shutdown complete")
	os.Exit(0)
}