// server.go
package main

import (
	"fmt"
	"log"
	"net/http"
	"strings"
)

var globalRoutes RouteMap

// StartServer initializes the routing and starts the HTTP listener.
func StartServer() {
	InitCache()

	// Initial Scan
	var err error
	globalRoutes, err = ScanContent("content")
	if err != nil {
		log.Fatalf("Failed to scan content: %v", err)
	}

	// SINGLE ENTRY POINT
	http.HandleFunc("/", handleRequest)

	fmt.Println("Server is online at http://localhost:8080")
	if err := http.ListenAndServe(":8080", nil); err != nil {
		log.Fatal(err)
	}
}

func handleRequest(w http.ResponseWriter, r *http.Request) {
	// 1. Handle Test Mode (Re-scan on every request)
	if TestMode {
		w.Header().Set("Cache-Control", "no-store, no-cache, must-revalidate, max-age=0")
		routes, err := ScanContent("content")
		if err == nil {
			globalRoutes = routes
		}
	}

	// 2. Normalize Request Path
	reqPath := strings.ToLower(r.URL.Path)

	// 3. Look up in Route Map
	file, found := globalRoutes[reqPath]
	if !found {
		http.NotFound(w, r)
		return
	}

	// 4. Get Content Path (Ensures cache is fresh)
	cachePath, err := GetContentPath(file)
	if err != nil {
		log.Printf("Error serving %s: %v", file.OriginalPath, err)
		http.Error(w, "Internal Server Error", 500)
		return
	}

	// 5. Serve File
	// http.ServeFile handles Content-Type, Range requests, and Caching headers automatically.
	http.ServeFile(w, r, cachePath)
}