     init?(_ lrcContents: String) {
         lyrics = []
         idTags = [:]
-        metaData = [:]
+        metadata = [:]
         
         guard let regexForIDTag = try? NSRegularExpression(pattern: "\\[[^\\]]+:[^\\]]+\\]") else {
             return

    
    var lyrics: [LXLyricsLine]
    var idTags: [idTagKey: String]
    var metaData: [metadataKey: Any]
    
    var offset: Int {
        get {

        lyrics.sort() { $0.position < $1.position }
    }
    
    init?(metadata: [metadataKey: Any]) {
        if let lrcURL = metadata[.lyricsURL] as? URL, let lrcContent = try? String(contentsOf: lrcURL) {
            self.init(lrcContent)
            self.metadata = metadata
        }
        return nil
    }
    
    subscript(at position: Double) -> (current:LXLyricsLine?, next:LXLyricsLine?) {
        for (index, line) in lyrics.enumerated() {
            if line.position > position {
