Accessing Bookmarklet Variables

[tjsail33]

So I have a piece of code that is run as a bookmarklet that I am trying to edit, but I am unable to get it to work. The code checks for the presence of a button (the Awesome Button) and then clicks it every 15s, until the page is refreshed. What I want to do is make the code cancelable by having a box pop up that says "Run AutoBop?" and then has an OK/Cancel button. I can make all of this work, but the cancel button does not cause the initial interval to stop. Any advice?

The original code:

(function(w) {
                        var interval;
			var log = function(str) {
				if (typeof w.console != 'undefined') {
					w.console.log(str);
				} else {
					// alert(str);
				}
			};
			if (typeof w.clearInterval === 'undefined') {
				w.clearInterval = function() {};
			}
			log('Loading AutoBop..');
			if (typeof w.jQuery == 'undefined') {
				log('Error: jQuery not loaded!');
				return;
			}
			var $ = w.jQuery;
			var $b;
			var findAwesome = function() {
				var btnSize = [126, 44];
				var btnPos = [370, 555];
				log('findAwesome');
				$('a').each(function(idx, el) {
					if ($b) {
						return;
					}
					log('Checking element:');
					log(el);
					var btnOffset = $(el).position();
					if (btnOffset.left != btnPos[0] || btnOffset.top != btnPos[1]) {
						log('Position mismatch. Elem:');
						log(btnOffset);
						return;
					}
					if ($(el).width() != btnSize[0] || $(el).height() != btnSize[1]) {
						log('Width/Height mismatch. Elem: ' + $(el).width() + 'x' + $(el).height());
						return;
					}
					$b = $(el);
					log('Found awesome button');
				});
				return $b;
			};
			var c = function() {
				if (!$b) {
					$b = findAwesome();
				}
				if ($b && $b.size()) {
					log('Clicking AWESOME! button');
					$b.each(function(idx, el) {
						var btnOffset = $(el).offset();
						var e = $.Event('click');
						e.target = el;
						var r = Math.floor(Math.random() * 20);
						e.pageX = btnOffset.left + r;
						e.pageY = btnOffset.top + r;
						e.relatedTarget = $(el).parent().get(0);
						$(el).trigger(e);
						log('Clicked!');
					});
				} else {
					log('Error: Couldn\'t find any buttons to click');
					w.clearInterval();
					return false;
				}
				return true;
			};
			log('Attempting first run..');
			if (c()) {
				log('That seemed to work; setting up the timer');
				interval=setInterval(c, 15000);
			} else {
				log('Error clicking button; not setting timer');
			}
			log('AutoBop load complete');
		})(window);

My attempt at modifying the code:

(function(w) {
			var interval;
			var log = function(str) {
				if (typeof w.console != 'undefined') {
					w.console.log(str);
				} else {
					// alert(str);
				}
			};
			if(!confirm('Run AutoBopV2?')) {
				w.clearInterval(interval);
				log('AutoBop Cancelled!');
				return false;
			}
			if (typeof w.clearInterval === 'undefined') {
				w.clearInterval = function() {};
			}
			log('Loading AutoBop..');
			if (typeof w.jQuery == 'undefined') {
				log('Error: jQuery not loaded!');
				return;
			}
			var $ = w.jQuery;
			var $b;
			var findAwesome = function() {
				var btnSize = [126, 44];
				var btnPos = [370, 555];
				log('findAwesome');
				$('a').each(function(idx, el) {
					if ($b) {
						return;
					}
					log('Checking element:');
					log(el);
					var btnOffset = $(el).position();
					if (btnOffset.left != btnPos[0] || btnOffset.top != btnPos[1]) {
						log('Position mismatch. Elem:');
						log(btnOffset);
						return;
					}
					if ($(el).width() != btnSize[0] || $(el).height() != btnSize[1]) {
						log('Width/Height mismatch. Elem: ' + $(el).width() + 'x' + $(el).height());
						return;
					}
					$b = $(el);
					log('Found awesome button');
				});
				return $b;
			};
			var c = function() {
				if (!$b) {
					$b = findAwesome();
				}
				if ($b && $b.size()) {
					log('Clicking AWESOME! button');
					$b.each(function(idx, el) {
						var btnOffset = $(el).offset();
						var e = $.Event('click');
						e.target = el;
						var r = Math.floor(Math.random() * 20);
						e.pageX = btnOffset.left + r;
						e.pageY = btnOffset.top + r;
						e.relatedTarget = $(el).parent().get(0);
						$(el).trigger(e);
						log('Clicked!');
					});
				} else {
					log('Error: Couldn\'t find any buttons to click');
					w.clearInterval();
					return false;
				}
				return true;
			};
			log('Attempting first run..');
			if (c()) {
				log('That seemed to work; setting up the timer');
				interval=setInterval(c, 15000);
			} else {
				log('Error clicking button; not setting timer');
			}
			log('AutoBop load complete');
		})(window);