package ch.hevs.isc.slopify_v2

import java.io.{File, FileInputStream, FileOutputStream, ObjectInput, ObjectInputStream, ObjectOutputStream}

object DataBaseHelper {
  def create(directory:String) : DataBase = {
    val db = new DataBase()
    for (a <- new File(directory).listFiles() if a.isDirectory) {
      val artistName = a.getName
      //println(s"found new artist : $artistName")
      val artist: Artist = new Artist(artistName)

      for (b <- a.listFiles() if b.isDirectory ) {
        val albumName = b.getName
        //println(s"found new album $albumName for artist : $artistName")
        val album: Album = new Album(albumName)

        for (c <- b.listFiles() if c.isFile if c.getName.toLowerCase().endsWith(".mp3") ) {
          val fileName = c.getName.substring(0, c.getName.length - 4)
          val format1 = """(\d*) (.*)""".r
          val format2 = """(\d*)-(\d*) (.*)""".r
          val format3 = """(\d*)-(.*)""".r
          var songName: String = ""
          var songNumber: Int = 0

          fileName match {
            case format1(nr, name) => {
              //println(s"found song nr #$nr name:'$name' in album '$albumName' for artist : '${a.getName}'")
              songName = name
              songNumber = Integer.parseInt(nr)
            }
            case format2(cd, nr, name) => {
              //println(s"found song nr #$nr on cd#$cd name:'$name' in album '$albumName' for artist : '${a.getName}'")
              songName = name
              songNumber = Integer.parseInt(nr)
            }
            case format3(nr, name) => {
              //println(s"found song nr #$nr name:'$name' in album '$albumName' for artist : '$artistName'")
              songName = name
              songNumber = Integer.parseInt(nr)
            }
          }

          val song: Song = new Song(songName, songNumber)
          album.addSong(song)
        }
        artist.addAlbum(album)
      }
      db.addArtist(artist)
    }

    return db
  }

  def save(fileName: String, db: DataBase) : Unit = {
    val fos: FileOutputStream = new FileOutputStream(fileName)
    val oos: ObjectOutputStream = new ObjectOutputStream(fos)
    oos.writeObject(db)
    oos.close()
  }
  def load(fileName:String) : DataBase = {
    val fis: FileInputStream = new FileInputStream(fileName)
    val ois: ObjectInputStream = new ObjectInputStream(fis)
    val db: DataBase = ois.readObject().asInstanceOf[DataBase]
    ois.close()
    return db
  }

  def main(args: Array[String]): Unit = {
    val db: DataBase = create("res/songs")
    println(db)
    val artists: Array[Artist] = db.getArtists()
    println(artists(0))

    save("res/db.bin", db)
    val db2: DataBase = load("res/db.bin")
    println(db2)
    val artists2: Array[Artist] = db2.getArtists()
    println(artists2(0))
  }
}