main.go

package main

import (
	"log"
	"net/http"
	"os"
	"time"

	"github.com/go-chi/chi/v5"
	"github.com/go-chi/chi/v5/middleware"
	"github.com/go-chi/cors"
	"github.com/joho/godotenv"
	"github.com/xqsit94/cypher/internal/handlers"
)

func securityHeaders(next http.Handler) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		w.Header().Set("X-Frame-Options", "DENY")
		w.Header().Set("X-Content-Type-Options", "nosniff")
		w.Header().Set("Content-Security-Policy", "default-src 'self'; style-src 'self' 'unsafe-inline'; script-src 'self'")
		w.Header().Set("Referrer-Policy", "strict-origin-when-cross-origin")
		w.Header().Set("Permissions-Policy", "geolocation=(), microphone=(), camera=()")
		next.ServeHTTP(w, r)
	})
}

func main() {
	// Load environment variables
	if err := godotenv.Load(); err != nil {
		log.Println("No .env file found, proceeding with environment variables")
	}

	// Initialize router
	r := chi.NewRouter()

	// Middleware
	r.Use(middleware.Logger)
	r.Use(middleware.Recoverer)
	r.Use(middleware.RealIP)
	r.Use(securityHeaders)
	r.Use(middleware.ThrottleBacklog(20, 10, time.Second*5))

	// Get port from environment
	port := os.Getenv("PORT")
	if port == "" {
		port = "8000"
	}

	// Get allowed origins from environment or use default based on port
	allowedOrigins := []string{"http://localhost:" + port}
	if origins := os.Getenv("ALLOWED_ORIGINS"); origins != "" {
		allowedOrigins = []string{origins}
	}

	r.Use(cors.Handler(cors.Options{
		AllowedOrigins:   allowedOrigins,
		AllowedMethods:   []string{"GET", "POST", "OPTIONS"},
		AllowedHeaders:   []string{"Accept", "Authorization", "Content-Type"},
		ExposedHeaders:   []string{"Link"},
		AllowCredentials: true,
		MaxAge:           300,
	}))

	// File server for static files
	fileServer := http.FileServer(http.Dir("static"))
	r.Handle("/static/*", http.StripPrefix("/static/", fileServer))

	// Routes
	r.Get("/", handlers.HomeHandler)
	r.Post("/encrypt", handlers.EncryptHandler)
	r.Post("/decrypt", handlers.DecryptHandler)

	log.Printf("Server starting on port %s", port)
	if err := http.ListenAndServe(":"+port, r); err != nil {
		log.Fatal(err)
	}
}