AngularJS resize directive

resize.js

/*
    Usage

    <div resize="{'attr': 'height', '*': 0.375}"> ...
*/

'use strict';

Application.directive('resize', function ($window) {
	return {
		restrict: 'A',
		scope: {
			'resize' : '@'
		},
		link: function(scope, element, attrs) {
			var params = eval('(' + scope.resize + ')');

			var w = angular.element($window);
			scope.getWindowDimensions = function () {
				return { 'h': $window.innerHeight, 'w': $window.innerWidth };
			};

			scope.$watch(scope.getWindowDimensions, function (newValue, oldValue) {

				var value = (params.attr == 'height') ? newValue.h : newValue.w;

				if (params['-'] && !isNaN(params['-'])) {
					value = value - params['-'];
				}
				if (params['+'] && !isNaN(params['+'])) {
					value = value + params['+'];
				}
				if (params['*'] && !isNaN(params['*'])) {
					value = parseInt(value * params['*']);
				}
				if (params['/'] && !isNaN(params['/'])) {
					value = parseInt(value / params['/']);
				}

				if (params.attr == 'height' || params.attr == 'both') {
					angular.element(element).height(value);
				}
				if (params.attr == 'width' || params.attr == 'both') {
					angular.element(element).width(value);
				}
			}, true);

			w.bind('resize', function () {
				scope.$apply();
			});
			
		}
	};
});