var CONSTANTS = require("./constants");

var FILL_SIZE = 4;
var PRESET_LENGTH = 257;

function creator(data) {
  var buffer = [];
  for (var i = 0; i < CONSTANTS.HEADER.length; i++) {
    buffer.push(CONSTANTS.HEADER.charCodeAt(i));
  }
  buffer.push(26); // <ctrl-z>
  var ending = "!--";
  for (var i = 0; i < ending.length; i++) {
    buffer.push(ending.charCodeAt(i));
  }
  if (!data.presets) {
    throw new Error("Eqf data is missing presets");
  }
  data.presets.forEach(function(preset) {
    var k = 0;
    for (; k < preset.name.length; k++) {
      buffer.push(preset.name.charCodeAt(k));
    }
    for (; k < PRESET_LENGTH; k++) {
      buffer.push(0);
    }

    CONSTANTS.PRESET_VALUES.forEach(function(valueName) {
      buffer.push(64 - preset[valueName]); // Adjust for inverse values
    });
  });
  return new Uint8Array(buffer).buffer;
}

module.exports = creator;