package main

import (
	"log"
	"net/http"
	"os"
	"path/filepath"
	"strconv"
	"strings"

	"ai-media-hub/backend/handlers"
	"ai-media-hub/backend/models"
	"ai-media-hub/backend/services"

	"github.com/gin-gonic/gin"
)

func main() {
	root := envOrDefault("APP_ROOT", "/app")
	dbPath := envOrDefault("SQLITE_PATH", filepath.Join(root, "db", "media.db"))
	downloadsDir := envOrDefault("DOWNLOADS_DIR", filepath.Join(root, "downloads"))
	giphyDownloadDir := envOrDefault("GIPHY_DOWNLOAD_DIR", filepath.Join(downloadsDir, "giphy"))
	frontendDir := envOrDefault("FRONTEND_DIR", filepath.Join(root, "frontend"))
	workerScript := envOrDefault("WORKER_SCRIPT", filepath.Join(root, "worker", "downloader.py"))
	geminiAPIKey := os.Getenv("GEMINI_API_KEY")
	geminiModel := envOrDefault("GEMINI_MODEL", "gemini-2.5-flash")
	giphyEnabled := envBoolOrDefault("GIPHY_ENABLED", true)
	giphyAPIKey := os.Getenv("GIPHY_API_KEY")
	giphyMaxResults := envIntOrDefault("GIPHY_MAX_RESULTS", 100)
	giphyRating := envOrDefault("GIPHY_RATING", "g")
	giphyLang := envOrDefault("GIPHY_LANG", "en")

	db, err := models.InitDB(dbPath)
	if err != nil {
		log.Fatal(err)
	}
	defer db.Close()

	if err := handlers.EnsurePaths(downloadsDir, workerScript); err != nil {
		log.Fatal(err)
	}
	if geminiAPIKey == "" {
		log.Printf("warning: GEMINI_API_KEY is not configured; query expansion will use fallback behavior")
	}
	if giphyEnabled && strings.TrimSpace(giphyAPIKey) == "" {
		log.Fatal("GIPHY_ENABLED is true but GIPHY_API_KEY is not configured")
	}
	if err := os.MkdirAll(giphyDownloadDir, 0o755); err != nil {
		log.Fatal(err)
	}

	geminiService := services.NewGeminiService(geminiAPIKey, geminiModel)
	giphyService := services.NewGiphyService(services.GiphyConfig{
		Enabled:     giphyEnabled,
		APIKey:      giphyAPIKey,
		MaxResults:  giphyMaxResults,
		Rating:      giphyRating,
		Lang:        giphyLang,
		DownloadDir: giphyDownloadDir,
	}, geminiService)

	app := &handlers.App{
		DB:              db,
		DownloadsDir:    downloadsDir,
		PreviewCacheDir: filepath.Join(downloadsDir, ".preview-cache"),
		WorkerScript:    workerScript,
		SearchService: services.NewSearchService(
			os.Getenv("SEARXNG_BASE_URL"),
			os.Getenv("SEARXNG_GOOGLE_VIDEO_ENGINE"),
			os.Getenv("SEARXNG_WEB_ENGINE"),
		),
		GeminiService: geminiService,
		GiphyService:  giphyService,
		Hub:           handlers.NewHub(),
	}
	app.SearchService.Debug = func(message string, data any) {
		app.Hub.Broadcast("debug", gin.H{"message": message, "data": data})
	}
	app.GeminiService.Debug = func(message string, data any) {
		app.Hub.Broadcast("debug", gin.H{"message": message, "data": data})
	}
	app.GiphyService.Debug = func(message string, data any) {
		app.Hub.Broadcast("debug", gin.H{"message": message, "data": data})
	}

	router := gin.Default()
	handlers.RegisterRoutes(router, app)
	router.StaticFile("/", filepath.Join(frontendDir, "index.html"))
	router.StaticFile("/app.js", filepath.Join(frontendDir, "app.js"))
	router.StaticFile("/style.css", filepath.Join(frontendDir, "style.css"))
	router.NoRoute(func(c *gin.Context) {
		c.File(filepath.Join(frontendDir, "index.html"))
	})
	router.NoMethod(func(c *gin.Context) {
		c.JSON(http.StatusMethodNotAllowed, gin.H{"error": "method not allowed"})
	})

	addr := envOrDefault("APP_ADDR", ":8080")
	log.Printf("server listening on %s", addr)
	if err := router.Run(addr); err != nil {
		log.Fatal(err)
	}
}

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

func envBoolOrDefault(key string, fallback bool) bool {
	value := strings.TrimSpace(strings.ToLower(os.Getenv(key)))
	switch value {
	case "1", "true", "yes", "on":
		return true
	case "0", "false", "no", "off":
		return false
	case "":
		return fallback
	default:
		return fallback
	}
}

func envIntOrDefault(key string, fallback int) int {
	value := strings.TrimSpace(os.Getenv(key))
	if value == "" {
		return fallback
	}
	parsed, err := strconv.Atoi(value)
	if err != nil {
		return fallback
	}
	return parsed
}