persephone/Persephone/MPDClient/Models/MPDSong.swift

//
//  MPDClientSong.swift
//  Persephone
//
//  Created by Daniel Barber on 2019/2/03.
//  Copyright © 2019 Dan Barber. All rights reserved.
//

import Foundation
import mpdclient

extension MPDClient {
  class MPDSong {
    let song: OpaquePointer
    
    enum TagType: Int {
      case unknown = -1
      case artist, album, albumArtist, title, track, name,
        genre, date, composer, performer, comment, disc

      case musicBrainzArtistId
      case musicBrainzAlbumId
      case musicBrainzAlbumArtistId
      case musicBrainzTrackId
      case musicBrainzReleaseTrackId

      case originalDate

      case artistSort
      case albumArtistSort
      case albumSort

      case tagCount
    }

    init(_ song: OpaquePointer) {
      self.song = song
    }

    deinit {
      mpd_song_free(song)
    }

    var uri: UnsafePointer<Int8> {
      return mpd_song_get_uri(song)
    }

    var uriString: String {
      return String(cString: uri)
    }

    var album: MPDAlbum {
      return MPDAlbum(
        title: getTag(.album),
        artist: artist
      )
    }

    var artist: String {
      if getTag(.albumArtist) != "" {
        return getTag(.albumArtist)
      } else {
        return getTag(.artist)
      }
    }

    func getTag(_ tagType: TagType) -> String {
      let mpdTagType = mpd_tag_type(rawValue: Int32(tagType.rawValue))

      guard let tag = mpd_song_get_tag(song, mpdTagType, 0)
        else { return "" }
      
      return String(cString: tag)
    }
  }
}