/**
 * jQuery Plugin to obtain touch gestures from iPhone, iPod Touch and iPad, should also work with Android mobile phones (not tested yet!)
 * Common usage: wipe images (left and right to show the previous or next image)
 * 
 * @author Andreas Waltl, netCU Internetagentur (http://www.netcu.de)
 * @version 1.1.1 (9th December 2010) - fix bug (older IE's had problems)
 * @version 1.1 (1st September 2010) - support wipe up and wipe down
 * @version 1.0 (15th July 2010)
 */
(function ($) {
    $.fn.touchwipe = function (settings) {
        var config = {
            min_move_x: 20,
            min_move_y: 20,
            wipeLeft: function () {},
            wipeRight: function () {},
            wipeUp: function () {},
            wipeDown: function () {},
            preventDefaultEvents: true
        };
        if (settings) $.extend(config, settings);
        this.each(function () {
            var startX;
            var startY;
            var isMoving = false;

            function cancelTouch() {
                this.removeEventListener('touchmove', onTouchMove);
                startX = null;
                isMoving = false
            }
            function onTouchMove(e) {
                if (config.preventDefaultEvents) {
                    e.preventDefault()
                }
                if (isMoving) {
                    var x = e.touches[0].pageX;
                    var y = e.touches[0].pageY;
                    var dx = startX - x;
                    var dy = startY - y;
                    if (Math.abs(dx) >= config.min_move_x) {
                        cancelTouch();
                        if (dx > 0) {
                            config.wipeLeft()
                        } else {
                            config.wipeRight()
                        }
                    } else if (Math.abs(dy) >= config.min_move_y) {
                        cancelTouch();
                        if (dy > 0) {
                            config.wipeDown()
                        } else {
                            config.wipeUp()
                        }
                    }
                }
            }
            function onTouchStart(e) {
                if (e.touches.length == 1) {
                    startX = e.touches[0].pageX;
                    startY = e.touches[0].pageY;
                    isMoving = true;
                    this.addEventListener('touchmove', onTouchMove, false)
                }
            }
            if ('ontouchstart' in document.documentElement) {
                this.addEventListener('touchstart', onTouchStart, false)
            }
        });
        return this
    }
})(jQuery);