package main

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

	"github.com/food-ai/backend/internal/auth"
	"github.com/food-ai/backend/internal/config"
	"github.com/food-ai/backend/internal/database"
	"github.com/food-ai/backend/internal/gemini"
	"github.com/food-ai/backend/internal/ingredient"
	"github.com/food-ai/backend/internal/middleware"
	"github.com/food-ai/backend/internal/pexels"
	"github.com/food-ai/backend/internal/product"
	"github.com/food-ai/backend/internal/recommendation"
	"github.com/food-ai/backend/internal/savedrecipe"
	"github.com/food-ai/backend/internal/server"
	"github.com/food-ai/backend/internal/user"
)

// jwtAdapter adapts auth.JWTManager to middleware.AccessTokenValidator.
type jwtAdapter struct {
	jm *auth.JWTManager
}

func (a *jwtAdapter) ValidateAccessToken(tokenStr string) (*middleware.TokenClaims, error) {
	claims, err := a.jm.ValidateAccessToken(tokenStr)
	if err != nil {
		return nil, err
	}
	return &middleware.TokenClaims{
		UserID: claims.UserID,
		Plan:   claims.Plan,
	}, nil
}

func main() {
	logger := slog.New(slog.NewJSONHandler(os.Stdout, &slog.HandlerOptions{
		Level: slog.LevelInfo,
	}))
	slog.SetDefault(logger)

	if err := run(); err != nil {
		slog.Error("fatal error", "err", err)
		os.Exit(1)
	}
}

func run() error {
	cfg, err := config.Load()
	if err != nil {
		return fmt.Errorf("load config: %w", err)
	}

	ctx, stop := signal.NotifyContext(context.Background(), syscall.SIGINT, syscall.SIGTERM)
	defer stop()

	pool, err := database.NewPool(ctx, cfg.DatabaseURL)
	if err != nil {
		return fmt.Errorf("connect to database: %w", err)
	}
	defer pool.Close()
	slog.Info("connected to database")

	// Firebase auth
	firebaseAuth, err := auth.NewFirebaseAuthOrNoop(cfg.FirebaseCredentialsFile)
	if err != nil {
		return fmt.Errorf("init firebase auth: %w", err)
	}

	// JWT manager
	jwtManager := auth.NewJWTManager(cfg.JWTSecret, cfg.JWTAccessDuration, cfg.JWTRefreshDuration)

	// User domain
	userRepo := user.NewRepository(pool)
	userService := user.NewService(userRepo)
	userHandler := user.NewHandler(userService)

	// Auth domain
	authService := auth.NewService(firebaseAuth, userRepo, jwtManager)
	authHandler := auth.NewHandler(authService)

	// Auth middleware
	authMW := middleware.Auth(&jwtAdapter{jm: jwtManager})

	// External API clients
	geminiClient := gemini.NewClient(cfg.GeminiAPIKey)
	pexelsClient := pexels.NewClient(cfg.PexelsAPIKey)

	// Ingredient domain
	ingredientRepo := ingredient.NewRepository(pool)
	ingredientHandler := ingredient.NewHandler(ingredientRepo)

	// Product domain
	productRepo := product.NewRepository(pool)
	productHandler := product.NewHandler(productRepo)

	// Recommendation domain
	recommendationHandler := recommendation.NewHandler(geminiClient, pexelsClient, userRepo, productRepo)

	// Saved recipes domain
	savedRecipeRepo := savedrecipe.NewRepository(pool)
	savedRecipeHandler := savedrecipe.NewHandler(savedRecipeRepo)

	// Router
	router := server.NewRouter(
		pool,
		authHandler,
		userHandler,
		recommendationHandler,
		savedRecipeHandler,
		ingredientHandler,
		productHandler,
		authMW,
		cfg.AllowedOrigins,
	)

	srv := &http.Server{
		Addr:         fmt.Sprintf(":%d", cfg.Port),
		Handler:      router,
		ReadTimeout:  10 * time.Second,
		WriteTimeout: 30 * time.Second,
		IdleTimeout:  60 * time.Second,
	}

	go func() {
		slog.Info("server starting", "port", cfg.Port)
		if err := srv.ListenAndServe(); err != nil && err != http.ErrServerClosed {
			slog.Error("server error", "err", err)
		}
	}()

	<-ctx.Done()
	slog.Info("shutting down...")

	shutdownCtx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
	defer cancel()

	return srv.Shutdown(shutdownCtx)
}