package main

import (
	"log"
	"net/http"
	"os"
	"path/filepath"
	"strings"
	"time"
)

var (
	port      = os.Getenv("PODCAST_PORT")       // Es: ":8080"
	baseURL   = os.Getenv("PODCAST_BASE_URL")   // Es: "http://mioserver.com"
	audioDir  = os.Getenv("PODCAST_AUDIO_DIR")  // Es: "/data/podcast/audio"
	coversDir = os.Getenv("PODCAST_COVERS_DIR") // Es: "/data/podcast/covers"
	podTitle  = os.Getenv("PODCAST_TITLE")      // Es: "Il Mio Podcast"
)

func init() {
	// Verifica variabili d'ambiente
	for _, v := range []struct {
		name  string
		value string
	}{
		{"PODCAST_PORT", port},
		{"PODCAST_BASE_URL", baseURL},
		{"PODCAST_AUDIO_DIR", audioDir},
		{"PODCAST_COVERS_DIR", coversDir},
		{"PODCAST_TITLE", podTitle},
	} {
		if v.value == "" {
			log.Fatalf("Variabile d'ambiente mancante: %s", v.name)
		}
	}
}

func main() {
	// Handler principale
	http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
		// Verifica se la richiesta è per un file audio o cover
		requestedFile := filepath.Clean(r.URL.Path)
		isAudio := strings.HasPrefix(requestedFile, "/audio/")
		isCover := strings.HasPrefix(requestedFile, "/covers/")
		// logghiamo che succede
		log.Println("Richiesta da: ", r.UserAgent(), " per ", r.RequestURI)
		if isAudio || isCover {
			// Servi il file richiesto
			http.ServeFile(w, r, filepath.Join(".", requestedFile))
			return
		}

		// Altrimenti servi sempre l'RSS
		if err := generateRSS(); err != nil {
			http.Error(w, err.Error(), http.StatusInternalServerError)
			return
		}
		http.ServeFile(w, r, "feed.xml")
	})

	// Aggiornamento periodico
	go func() {
		for {
			time.Sleep(5 * time.Minute)
			if err := generateRSS(); err != nil {
				log.Printf("Aggiornamento RSS fallito: %v", err)
			}
		}
	}()

	log.Printf("Server in ascolto su %s%s", baseURL, port)
	log.Fatal(http.ListenAndServe(port, nil))
}