Teoria.js - tuning interface design

teoria-tuning-design.js

var teoria = {};

teoria.note = function(name, tuning) {
  return (new TeoriaNote(name, tuning));
};


// how should we handle multiple optional parameters like duration and tuning?
// should be pass in a { param } object instead of individual parameters?
function TeoriaNote(name, tuning) {
  this.name = name;
  var tuning = tuning || '12tet';
  this.tuning = namedTuning(tuning);
}


TeoriaNote.prototype = {
  // would key need to be moved to each tuning class?
  // it looks like the key function assumes 12 notes per octave
  key: function(whitenotes) {
    //...
  },

  fq: function(concertPitch) {
    concertPitch = concertPitch || 440;

    return this.tuning.frequency(this.key(), concertPitch);
  }

};


// case statement to create instance of tuning class based on string
// is there a better way to do this?
function namedTuning(name) {

  switch (name) {
    case '12tet':
      return new Tuning12tet();
    break;

  }

}



// what parameter(s) would be passed to the tuning constructors?
function Tuning12tet() {

}

Tuning12tet.prototype = {

  frequency: function(key, concertPitch) {

    return concertPitch * Math.pow(2, (key - 49) / 12);
  }

};


// usage
var a4 = teoria.note('a4', '12tet');
a4.fq();