package main

import (
	"crypto/rand"
	"encoding/hex"
	"log"
	"net/http"
	"os"
	"strings"

	"gpt-plus/internal/db"
	"gpt-plus/internal/handler"
	"gpt-plus/internal/task"
	"gpt-plus/web"

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

func main() {
	_ = godotenv.Load()

	port := os.Getenv("PORT")
	if port == "" {
		port = "8080"
	}
	dbPath := os.Getenv("DB_PATH")
	if dbPath == "" {
		dbPath = "./gptplus.db"
	}
	jwtSecret := os.Getenv("JWT_SECRET")
	if jwtSecret == "" {
		b := make([]byte, 32)
		rand.Read(b)
		jwtSecret = hex.EncodeToString(b)
		log.Println("[init] JWT_SECRET not set, using random secret (sessions won't survive restart)")
	}
	encKey := os.Getenv("ENCRYPTION_KEY")
	if encKey != "" {
		if err := db.SetEncryptionKey(encKey); err != nil {
			log.Fatalf("[init] invalid ENCRYPTION_KEY: %v", err)
		}
	}

	devMode := os.Getenv("DEV_MODE") == "true"
	if devMode {
		gin.SetMode(gin.DebugMode)
	} else {
		gin.SetMode(gin.ReleaseMode)
	}

	// Init database
	if err := db.Init(dbPath); err != nil {
		log.Fatalf("[init] database init failed: %v", err)
	}
	log.Printf("[init] database ready: %s", dbPath)

	// Init auth
	handler.SetJWTSecret(jwtSecret)
	if err := handler.InitAdminPassword(); err != nil {
		log.Fatalf("[init] admin password init failed: %v", err)
	}

	// Seed default config
	handler.SeedDefaultConfigs()

	// Init task manager
	tm := task.NewTaskManager(db.GetDB())
	tm.Init()
	handler.SetTaskManager(tm)

	// Setup router
	r := handler.SetupRouter(devMode)

	// Serve frontend in production mode
	if !devMode {
		serveFrontend(r)
	}

	log.Printf("[init] server starting on :%s (dev=%v)", port, devMode)
	if err := r.Run(":" + port); err != nil {
		log.Fatalf("server error: %v", err)
	}
}

func serveFrontend(r *gin.Engine) {
	frontendFS, err := web.FrontendFS()
	if err != nil {
		log.Printf("[init] frontend not embedded, skipping static file serving")
		return
	}

	// Serve static assets
	httpFS := http.FS(frontendFS)
	r.NoRoute(func(c *gin.Context) {
		path := c.Request.URL.Path

		// API routes that don't match return 404 JSON
		if strings.HasPrefix(path, "/api/") {
			c.JSON(http.StatusNotFound, gin.H{"error": "API route not found"})
			return
		}

		// Try to serve the file directly
		trimmed := strings.TrimPrefix(path, "/")
		if trimmed == "" {
			trimmed = "index.html"
		}
		if f, err := frontendFS.Open(trimmed); err == nil {
			f.Close()
			c.FileFromFS(path, httpFS)
			return
		}

		// SPA fallback: serve index.html for all non-file routes
		c.FileFromFS("/", httpFS)
	})
}