package main

import (
	"bufio"
	"encoding/xml"
	"flag"
	"fmt"
	"log"
	"os"
)

var (
	docType = `<!DOCTYPE tv SYSTEM "xmltv.dtd">`
	output  = flag.String(
		"output",
		"-",
		"Write output to `file` (stdout by default)",
	)
)

func usage() {
	fmt.Fprintf(os.Stderr, "usage: epgpruner [-output file] URL\n")
	flag.PrintDefaults()
	os.Exit(2)
}

func main() {
	log.SetPrefix("epgtrim: ")
	log.SetFlags(0)
	flag.Usage = usage
	flag.Parse()
	if flag.NArg() != 1 {
		usage()
		os.Exit(1)
	}
	URL := flag.Args()[0]

	playlist, err := NewPlaylist(URL)
	if err != nil {
		log.Fatal(err)
	}

	outfile := os.Stdout
	if *output != "-" {
		f, err := os.Create(*output)
		if err != nil {
			log.Fatal(err)
		}
		outfile = f
		defer f.Close()
	}
	wr := bufio.NewWriter(outfile)
	defer wr.Flush()
	wr.Write([]byte(xml.Header + docType + "\n"))
	e := xml.NewEncoder(wr)
	e.Indent("", "    ")
	err = e.Encode(playlist.Schedule.EPG)
	if err != nil {
		log.Fatal(err)
	}
}