/* =============================================================

/*

/* Angular Smooth Scroll 1.7.0

/* Animates scrolling to elements, by David Oliveros.

/*

/* Callback hooks contributed by Ben Armston

/* https://github.com/benarmston

/*

/* Easing support contributed by Willem Liu.

/* https://github.com/willemliu

/*

/* Easing functions forked from Gaëtan Renaudeau.

/* https://gist.github.com/gre/1650294

/*

/* Infinite loop bugs in iOS and Chrome (when zoomed) by Alex Guzman.

/* https://github.com/alexguzman

/*

/* Influenced by Chris Ferdinandi

/* https://github.com/cferdinandi

/*

/*

/* Free to use under the MIT License.

/*

/* ============================================================= */

angular.module('smoothScroll', [])

// Scrolls the window to this element, optionally validating an expression

//

.directive('smoothScroll', ['$timeout', 'smoothScroll', function($timeout, smoothScroll){

return {

restrict: 'A',

scope: {

callbackBefore: '&',

callbackAfter: '&',

},

link: function($scope, $elem, $attrs){

$timeout(function(){

if ( typeof $attrs.scrollIf === 'undefined' || $attrs.scrollIf === 'true' ){

var callbackBefore = function(element) {

if ( $attrs.callbackBefore ) {

var exprHandler = $scope.callbackBefore({element: element});

if (typeof exprHandler === 'function') {

exprHandler(element);

}

}

}

var callbackAfter = function(element) {

if ( $attrs.callbackAfter ) {

var exprHandler = $scope.callbackAfter({element: element});

if (typeof exprHandler === 'function') {

exprHandler(element);

}

}

}

smoothScroll($elem[0], {

duration: $attrs.duration,

offset: $attrs.offset,

easing: $attrs.easing,

callbackBefore: callbackBefore,

callbackAfter: callbackAfter

});

}

});

}

};

}])

// Scrolls to a specified element ID when this element is clicked

//

.directive('scrollTo', ['smoothScroll', function(smoothScroll){

return {

restrict: 'A',

scope: {

callbackBefore: '&',

callbackAfter: '&',

},

link: function($scope, $elem, $attrs){

var targetElement;

$elem.on('click', function(e){

targetElement = document.getElementById($attrs.scrollTo);

if ( targetElement ) {

e.preventDefault();

var callbackBefore = function(element) {

if ( $attrs.callbackBefore ) {

var exprHandler = $scope.callbackBefore({element: element});

if (typeof exprHandler === 'function') {

exprHandler(element);

}

}

}

var callbackAfter = function(element) {

if ( $attrs.callbackAfter ) {

var exprHandler = $scope.callbackAfter({element: element});

if (typeof exprHandler === 'function') {

exprHandler(element);

}

}

}

smoothScroll(targetElement, {

duration: $attrs.duration,

offset: $attrs.offset,

easing: $attrs.easing,

callbackBefore: callbackBefore,

callbackAfter: callbackAfter

});

return false;

}

});

}

};

}])

// Smooth scrolls the window to the provided element.

//

.factory('smoothScroll', ['$timeout', function($timeout){

var getScrollLocation = function() {

return window.pageYOffset ? window.pageYOffset : document.documentElement.scrollTop;

};

var smoothScroll = function (element, options) {

$timeout(function(){

var startLocation = getScrollLocation(),

timeLapsed = 0,

percentage, position;

// Options

//

options = options || {};

var duration = options.duration || 800,

offset = options.offset || 0,

easing = options.easing || 'easeInOutQuart',

callbackBefore = options.callbackBefore || function() {},

callbackAfter = options.callbackAfter || function() {};

// Calculate the easing pattern

//

var easingPattern = function (type, time) {

if ( type == 'easeInQuad' ) return time * time; // accelerating from zero velocity

if ( type == 'easeOutQuad' ) return time * (2 - time); // decelerating to zero velocity

if ( type == 'easeInOutQuad' ) return time < 0.5 ? 2 * time * time : -1 + (4 - 2 * time) * time; // acceleration until halfway, then deceleration

if ( type == 'easeInCubic' ) return time * time * time; // accelerating from zero velocity

if ( type == 'easeOutCubic' ) return (--time) * time * time + 1; // decelerating to zero velocity

if ( type == 'easeInOutCubic' ) return time < 0.5 ? 4 * time * time * time : (time - 1) * (2 * time - 2) * (2 * time - 2) + 1; // acceleration until halfway, then deceleration

if ( type == 'easeInQuart' ) return time * time * time * time; // accelerating from zero velocity

if ( type == 'easeOutQuart' ) return 1 - (--time) * time * time * time; // decelerating to zero velocity

if ( type == 'easeInOutQuart' ) return time < 0.5 ? 8 * time * time * time * time : 1 - 8 * (--time) * time * time * time; // acceleration until halfway, then deceleration

if ( type == 'easeInQuint' ) return time * time * time * time * time; // accelerating from zero velocity

if ( type == 'easeOutQuint' ) return 1 + (--time) * time * time * time * time; // decelerating to zero velocity

if ( type == 'easeInOutQuint' ) return time < 0.5 ? 16 * time * time * time * time * time : 1 + 16 * (--time) * time * time * time * time; // acceleration until halfway, then deceleration

return time; // no easing, no acceleration

};

// Calculate how far to scroll

//

var getEndLocation = function (element) {

var location = 0;

if (element.offsetParent) {

do {

location += element.offsetTop;

element = element.offsetParent;

} while (element);

}

location = Math.max(location - offset, 0);

return location;

};

var endLocation = getEndLocation(element);

var distance = endLocation - startLocation;

// Stop the scrolling animation when the anchor is reached (or at the top/bottom of the page)

//

var stopAnimation = function () {

var currentLocation = getScrollLocation();

if ( position == endLocation || currentLocation == endLocation || ( (window.innerHeight + currentLocation) >= document.body.scrollHeight ) ) {

clearInterval(runAnimation);

callbackAfter(element);

}

};

// Scroll the page by an increment, and check if it's time to stop

//

var animateScroll = function () {

timeLapsed += 16;

percentage = ( timeLapsed / duration );

percentage = ( percentage > 1 ) ? 1 : percentage;

position = startLocation + ( distance * easingPattern(easing, percentage) );

window.scrollTo( 0, position );

stopAnimation();

};

// Init

//

callbackBefore(element);

var runAnimation = setInterval(animateScroll, 16);

});

};

return smoothScroll;

}]);