package cmdline

import (
	"flag"
	"fmt"
	"log"
	"os"
)

var (
	printDebug bool
	outputFile string
)

// func searchGoogle(song string, lg *log.Logger) {

// }

// func searchGenius(song string, lg *log.Logger) {

// }

func Main() int {
	programName := os.Args[0]
	errorLog := log.New(os.Stderr, "", 0)
	mainLog := log.New(os.Stdout, "", 0)

	flags := flag.NewFlagSet(os.Args[0], flag.ExitOnError)
	flags.Usage = func() {
		out := flags.Output()
		fmt.Fprintf(out, "Usage: %v [dir]\n\n", programName)
		fmt.Fprint(out, "  [dir] is optional; if not passed, '.' is used.\n\n")
		fmt.Fprint(out, "  By default, the server listens on localhost:8080. Both the\n")
		fmt.Fprint(out, "  host and the port are configurable with flags. Set the host\n")
		fmt.Fprint(out, "  to something else if you want the server to listen on a\n")
		fmt.Fprint(out, "  specific network interface. Setting the port to 0 will\n")
		fmt.Fprint(out, "  instruct the server to pick a random available port.\n\n")
		flags.PrintDefaults()
	}

	outputFlag := flags.String("output", "", "Lyrics filename")
	verboseFlag := flags.Bool("verbose", false, "Turn on debug. Default is false.")
	searchFlag := flags.String("search", "", "Name of song to search. If the name of the song is not a single word, put in quotes\"\"")

	flags.Parse(os.Args[1:])

	if len(flags.Args()) > 1 {
		errorLog.Println("Error: too many command-line arguments")
		flags.Usage()
		return 1
	}

	allSetFlags := flagsSet(flags)

	songToSearch := *searchFlag

	if len(songToSearch) == 0 {
		errorLog.Println("Error: the song name must be provided for search")
		flags.Usage()
		return 1
	}

	if allSetFlags["output"] {
		outputFile = *outputFlag
	} else {
		mainLog.Printf("Using %s as the name of the file(s) for downloaded lyrics..\n", songToSearch)
	}

	printDebug = *verboseFlag
	if printDebug {
		mainLog.Printf("Output flag: %s, Debug flag: %t, Search flag: %s\n", outputFile, printDebug, songToSearch)
	}

	return 0
}

// flagsSet returns a set of all the flags what were actually set on the
// command line.
func flagsSet(flags *flag.FlagSet) map[string]bool {
	s := make(map[string]bool)
	flags.Visit(func(f *flag.Flag) {
		s[f.Name] = true
	})
	return s
}