package main

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

	_ "github.com/example/sndit/backend/docs"
	"github.com/example/sndit/backend/internal/auth"
	"github.com/example/sndit/backend/internal/config"
	"github.com/example/sndit/backend/internal/db"
	devtools "github.com/example/sndit/backend/internal/dev"
	"github.com/example/sndit/backend/internal/downloads"
	"github.com/example/sndit/backend/internal/galleries"
	"github.com/example/sndit/backend/internal/media"
	"github.com/example/sndit/backend/internal/storage"
	"github.com/gin-gonic/gin"
	swaggerFiles "github.com/swaggo/files"
	ginSwagger "github.com/swaggo/gin-swagger"
)

// @title Noah Bianchi Studio API
// @version 1.0
// @description REST API for photographer galleries and client delivery.
// @schemes http https
// @BasePath /
// @securityDefinitions.apikey studioSession
// @in header
// @name Cookie
// @description Use the studio_session cookie as studio_session=<value>.
func main() {
	cfg := config.Load()
	ctx, stop := signal.NotifyContext(context.Background(), os.Interrupt, syscall.SIGTERM)
	defer stop()

	database, err := db.New(ctx, cfg.DBDriver, cfg.DatabaseDSN())
	if err != nil {
		log.Fatalf("database unavailable: %v", err)
	}
	defer database.Close()

	objectStorage, err := storage.NewMinIO(storage.Config{
		Endpoint:       cfg.StorageEndpoint,
		PublicEndpoint: cfg.StoragePublicEndpoint,
		AccessKey:      cfg.StorageAccessKey,
		SecretKey:      cfg.StorageSecretKey,
		Bucket:         cfg.StorageBucket,
		UseSSL:         cfg.StorageUseSSL,
		PublicUseSSL:   true,
	})
	if err != nil {
		log.Fatalf("storage unavailable: %v", err)
	}
	if err := objectStorage.EnsureBucket(ctx); err != nil {
		log.Fatalf("storage unavailable: %v", err)
	}

	authRepository := auth.NewRepository(database)
	authService, err := auth.NewService(authRepository, cfg.SessionSecret, cfg.CookieSecure)
	if err != nil {
		log.Fatalf("authentication unavailable: %v", err)
	}
	galleryRepository := galleries.NewRepository(database)
	mediaRepository := media.NewRepository(database)
	mediaProcessor := media.NewProcessor(mediaRepository, objectStorage, 2)
	defer mediaProcessor.Close()
	downloadRepository := downloads.NewRepository(database)
	downloadService := downloads.NewService(downloadRepository, mediaRepository, objectStorage, 1)
	defer downloadService.Close()

	authHandler := auth.NewHandler(authService)
	galleryHandler := galleries.NewHandler(galleryRepository, mediaRepository, objectStorage, authService)
	mediaHandler := media.NewHandler(mediaRepository, objectStorage, mediaProcessor, authService)
	downloadHandler := downloads.NewHandler(galleryRepository, mediaRepository, objectStorage, authService, downloadService)
	devHandler := devtools.NewHandler(database, objectStorage, authService, devtools.Config{
		DBDriver:        cfg.DBDriver,
		APIURL:          cfg.APIURL,
		StorageEndpoint: cfg.StorageEndpoint,
		StorageBucket:   cfg.StorageBucket,
		StorageUseSSL:   cfg.StorageUseSSL,
		CORSOrigins:     cfg.CORSOrigin,
		CookieSecure:    cfg.CookieSecure,
	})

	router := gin.New()
	router.Use(gin.Recovery(), withCORS(cfg.CORSOrigin), withLogging())
	router.GET("/health", health)
	router.GET("/swagger/*any", ginSwagger.WrapHandler(swaggerFiles.Handler,
		ginSwagger.DocExpansion("none"),
		ginSwagger.PersistAuthorization(true),
	))
	require := authService.Require()
	authHandler.RegisterRoutes(router)
	authHandler.RegisterProtectedRoutes(router, require)
	galleryHandler.RegisterProtectedRoutes(router, require)
	mediaHandler.RegisterRoutes(router, require)
	galleryHandler.RegisterPublicRoutes(router)
	downloadHandler.RegisterRoutes(router)
	devHandler.RegisterRoutes(router, require)

	server := &http.Server{
		Addr:              ":" + cfg.Port,
		Handler:           router,
		ReadHeaderTimeout: 5 * time.Second,
		ReadTimeout:       10 * time.Second,
		WriteTimeout:      10 * time.Second,
		IdleTimeout:       60 * time.Second,
	}

	go func() {
		addr := cfg.APIURL
		if addr == "" {
			addr = "http://localhost" + server.Addr
		}
		log.Printf("API listening on %s", addr)
		if err := server.ListenAndServe(); err != nil && err != http.ErrServerClosed {
			log.Fatalf("server failed: %v", err)
		}
	}()

	<-ctx.Done()
	shutdownCtx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
	defer cancel()
	if err := server.Shutdown(shutdownCtx); err != nil {
		log.Printf("server shutdown failed: %v", err)
	}
}

// health godoc
// @Summary Check API health
// @Tags system
// @Produce json
// @Success 200 {object} map[string]string
// @Router /health [get]
func health(c *gin.Context) {
	c.JSON(http.StatusOK, gin.H{"status": "ok"})
}

func withCORS(allowedOrigin string) gin.HandlerFunc {
	return func(c *gin.Context) {
		origin := c.GetHeader("Origin")
		if origin != "" && originAllowed(origin, allowedOrigin) {
			c.Header("Access-Control-Allow-Origin", origin)
			c.Header("Access-Control-Allow-Credentials", "true")
			c.Header("Vary", "Origin")
		}
		if c.Request.Method == http.MethodOptions {
			c.Header("Access-Control-Allow-Methods", "GET, POST, PATCH, DELETE, OPTIONS")
			c.Header("Access-Control-Allow-Headers", "Content-Type")
			c.Status(http.StatusNoContent)
			c.Abort()
			return
		}
		c.Next()
	}
}

func originAllowed(origin, configured string) bool {
	for _, allowed := range strings.Split(configured, ",") {
		allowed = strings.TrimRight(strings.TrimSpace(allowed), "/")
		if allowed == "*" || allowed == origin {
			return true
		}
	}
	return false
}

func withLogging() gin.HandlerFunc {
	return func(c *gin.Context) {
		started := time.Now()
		c.Next()
		log.Printf("%s %s %d %s", c.Request.Method, c.Request.URL.Path, c.Writer.Status(), time.Since(started).Round(time.Millisecond))
	}
}