// Command leaf is the Felt tournament engine binary. It starts all embedded
// infrastructure (LibSQL, NATS JetStream, WebSocket hub) and serves the
// SvelteKit SPA over HTTP.
package main

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

	feltauth "github.com/felt-app/felt/internal/auth"
	"github.com/felt-app/felt/internal/clock"
	feltnats "github.com/felt-app/felt/internal/nats"
	"github.com/felt-app/felt/internal/server"
	"github.com/felt-app/felt/internal/server/middleware"
	"github.com/felt-app/felt/internal/server/ws"
	"github.com/felt-app/felt/internal/store"
)

func main() {
	dataDir := flag.String("data-dir", "./data", "Data directory for database and files")
	addr := flag.String("addr", ":8080", "HTTP listen address")
	devMode := flag.Bool("dev", false, "Enable development mode (permissive CORS, dev seed data)")
	flag.Parse()

	log.SetFlags(log.LstdFlags | log.Lmsgprefix)
	log.SetPrefix("felt: ")

	log.Printf("starting (data-dir=%s, addr=%s, dev=%v)", *dataDir, *addr, *devMode)

	// Create root context with cancellation
	ctx, cancel := context.WithCancel(context.Background())
	defer cancel()

	// ---- 1. LibSQL Database ----
	db, err := store.Open(*dataDir, *devMode)
	if err != nil {
		log.Fatalf("failed to open database: %v", err)
	}
	defer db.Close()

	// Verify database is working
	var one int
	if err := db.QueryRow("SELECT 1").Scan(&one); err != nil {
		log.Fatalf("database health check failed: %v", err)
	}
	log.Printf("database ready")

	// ---- 2. Embedded NATS Server ----
	natsServer, err := feltnats.Start(ctx, *dataDir)
	if err != nil {
		log.Fatalf("failed to start NATS: %v", err)
	}
	defer natsServer.Shutdown()

	// ---- 3. JWT Signing Key (persisted in LibSQL) ----
	signingKey, err := feltauth.LoadOrCreateSigningKey(db.DB)
	if err != nil {
		log.Fatalf("failed to load/create signing key: %v", err)
	}

	// ---- 4. Auth Service ----
	jwtService := feltauth.NewJWTService(signingKey, 7*24*time.Hour) // 7-day expiry
	authService := feltauth.NewAuthService(db.DB, jwtService)

	// ---- 5. WebSocket Hub ----
	tokenValidator := func(tokenStr string) (string, string, error) {
		return middleware.ValidateJWT(tokenStr, signingKey)
	}

	// Tournament validator stub -- allows all for now
	// TODO: Implement tournament existence + access check against DB
	tournamentValidator := func(tournamentID string, operatorID string) error {
		return nil // Accept all tournaments for now
	}

	var allowedOrigins []string
	if *devMode {
		allowedOrigins = nil // InsecureSkipVerify will be used
	} else {
		allowedOrigins = []string{"*"} // Same-origin enforced by browser
	}

	hub := ws.NewHub(tokenValidator, tournamentValidator, allowedOrigins)
	defer hub.Shutdown()

	// ---- 6. Clock Registry ----
	clockRegistry := clock.NewRegistry(hub)
	defer clockRegistry.Shutdown()
	log.Printf("clock registry ready")

	// ---- 7. HTTP Server ----
	srv := server.New(server.Config{
		Addr:      *addr,
		SigningKey: signingKey,
		DevMode:   *devMode,
	}, db.DB, natsServer.Server(), hub, authService, clockRegistry)

	// Start HTTP server in goroutine
	go func() {
		if err := srv.ListenAndServe(); err != nil && err != http.ErrServerClosed {
			log.Fatalf("HTTP server error: %v", err)
		}
	}()

	log.Printf("ready (addr=%s, dev=%v)", *addr, *devMode)

	// ---- Signal Handling ----
	sigCh := make(chan os.Signal, 1)
	signal.Notify(sigCh, syscall.SIGINT, syscall.SIGTERM)

	sig := <-sigCh
	log.Printf("received signal: %s, shutting down...", sig)

	// Graceful shutdown in reverse startup order
	shutdownCtx, shutdownCancel := context.WithTimeout(context.Background(), 10*time.Second)
	defer shutdownCancel()

	// 7. HTTP Server
	if err := srv.Shutdown(shutdownCtx); err != nil {
		log.Printf("HTTP server shutdown error: %v", err)
	}

	// 6. Clock Registry (closed by defer)
	// 5. WebSocket Hub (closed by defer)
	// 4. NATS Server (closed by defer)
	// 3. Database (closed by defer)

	cancel() // Cancel root context

	log.Printf("shutdown complete")
}