M main.go → main.go

@@ -1,7 +1,89 @@ 
 package main
 
-import "fmt"
+import (
+	"fmt"
+	"math/rand"
+	"os"
+)
+
+var (
+	curdir string
+)
+
+func getallfiles() []string {
+	var files []string
+	f, err := os.Open(curdir)
+	if err != nil {
+		fmt.Println(err)
+		os.Exit(1)
+	}
+	files, err = f.Readdirnames(0)
+	if err != nil {
+		fmt.Println(err)
+		os.Exit(1)
+	}
+	f.Close()
+	var songs []string
+	for _, file := range files {
+		if file[len(file)-4:] == ".mp3" {
+			songs = append(songs, file)
+		}
+	}
+	return songs
+}
+
+func getargsongs() []string {
+	var songs []string
+	for _, song := range os.Args[1:] {
+		info, err := os.Stat(song)
+		if err == nil && len(song) > 4 && song[len(song)-4:] == ".mp3" && !info.IsDir() && info.Mode().IsRegular() {
+			songs = append(songs, song)
+		} else {
+			fmt.Println(song, "is not a valid mp3 file.")
+		}
+	}
+	return songs
+}
+
+func showqueue(songs []string) {
+	fmt.Println("Up Next:")
+	var loopmax int = 5
+	if len(songs) < loopmax {
+		loopmax = len(songs)
+	}
+	for i := 0; i < loopmax; i++ {
+		fmt.Printf("%d: %s\n", i+1, songs[i])
+	}
+}
+
+func shuffle(songs *[]string) {
+	var tmpstr string
+	var tmpint int
+	for i := 0; i < len(*songs); i++ {
+		tmpint = rand.Intn(len(*songs))
+		tmpstr = (*songs)[i]
+		(*songs)[i] = (*songs)[tmpint]
+		(*songs)[tmpint] = tmpstr
+	}
+}
 
 func main() {
-	fmt.Println("Welcome to Melgody! Now Playing:")
+	tmpstr, err := os.Getwd()
+	if err != nil {
+		fmt.Println("An error occured while getting the current directory.")
+		os.Exit(1)
+	}
+	curdir = tmpstr
+	var songs []string
+	if len(os.Args) <= 1 {
+		songs = getallfiles()
+	} else {
+		songs = getargsongs()
+	}
+	shuffle(&songs)
+	if len(songs) == 0 {
+		fmt.Println("No songs found.")
+		os.Exit(0)
+	}
+	showqueue(songs)
 }