var Hammer = require('./module/hammer');

/**
 * Register a touch event, taking place before a gesture
 * @param {Hammer} hammer       A hammer instance
 * @param {function} callback   Callback, called as callback(event)
 */
exports.onTouch = function (hammer, callback) {
  callback.inputHandler = function (event) {
    if (event.isFirst) {
      callback(event);
    }
  };

  hammer.on('hammer.input', callback.inputHandler);
};

/**
 * Register a release event, taking place after a gesture
 * @param {Hammer} hammer       A hammer instance
 * @param {function} callback   Callback, called as callback(event)
 */
exports.onRelease = function (hammer, callback) {
  callback.inputHandler = function (event) {
    if (event.isFinal) {
      callback(event);
    }
  };

  return hammer.on('hammer.input', callback.inputHandler);
};


/**
 * Unregister a touch event, taking place before a gesture
 * @param {Hammer} hammer       A hammer instance
 * @param {function} callback   Callback, called as callback(event)
 */
exports.offTouch = function (hammer, callback) {
  hammer.off('hammer.input', callback.inputHandler);
};

/**
 * Unregister a release event, taking place before a gesture
 * @param {Hammer} hammer       A hammer instance
 * @param {function} callback   Callback, called as callback(event)
 */
exports.offRelease = exports.offTouch;