
(function(root, factory) {
  if (typeof define === 'function' && define.amd) {
    define(factory);
  } else if (typeof exports === 'object') {
    module.exports = factory(require, exports, module);
  } else {
    root.scrollReveal = factory();
  }
}(this, function(require, exports, module) {

/*
                       _ _ _____                      _   _
                      | | |  __ \                    | | (_)
    ___  ___ _ __ ___ | | | |__) |_____   _____  __ _| |  _ ___
   / __|/ __| '__/ _ \| | |  _  // _ \ \ / / _ \/ _` | | | / __|
   \__ \ (__| | | (_) | | | | \ \  __/\ V /  __/ (_| | |_| \__ \
   |___/\___|_|  \___/|_|_|_|  \_\___| \_/ \___|\__,_|_(_) |___/ v2.2.0
                                                        _/ |
                                                       |__/

================================================================================

   scrollReveal.js (c) 2015 Julian Lloyd ( @julianlloyd )
   Licensed under MIT ( http://www.opensource.org/licenses/mit-license.php )

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

window.scrollReveal = (function( window ){

  'use strict';

  var _requestAnimFrame;
  var _extend;
  var _handler;
  var self;

  function scrollReveal( config ){

    self         = this;
    self.elems   = {};
    self.serial  = 1;
    self.blocked = false;
    self.config  = _extend( self.defaults, config );

    if ( self.isMobile() && !self.config.mobile || !self.isSupported() ){
      self.destroy();
      return;
    }

    if ( self.config.viewport === window.document.documentElement ){

      window.addEventListener( 'scroll', _handler, false );
      window.addEventListener( 'resize', _handler, false );

    } else {
      self.config.viewport.addEventListener( 'scroll', _handler, false );
    }

    self.init( true );
  }

  scrollReveal.prototype = {

    defaults: {

      enter:    'bottom',
      move:     '8px',
      over:     '0.6s',
      wait:     '0s',
      easing:   'ease',

      scale:    { direction: 'up', power: '5%' },
      rotate:   { x: 0, y: 0, z: 0 },

      opacity:  0,
      mobile:   false,
      reset:    false,

      //        Expects a reference to a DOM node (the <html> node by default)
      //        which is used as the context when checking element visibility.
      viewport: window.document.documentElement,

      //        'always' — delay every time an animation resets
      //        'onload' - delay only for animations triggered by first load
      //        'once'   — delay only the first time an animation reveals
      delay:    'once',

      //        vFactor changes when an element is considered in the viewport.
      //        The default value of 0.60 means 60% of an element must be
      //        visible for its reveal animation to trigger.
      vFactor:  0.60,

      complete: function( el ){} // Note: reset animations do not complete.
    },

    // Queries the DOM, builds scrollReveal elements and triggers animation.
    // @param {boolean} flag — a hook for controlling delay on first load.
    init: function( flag ){

      var serial;
      var elem;
      var query;

      query = Array.prototype.slice.call( self.config.viewport.querySelectorAll('[data-sr]') );
      query.forEach(function( el ){

        serial      = self.serial++;
        elem        = self.elems[ serial ] = { domEl: el };
        elem.config = self.configFactory( elem );
        elem.styles = self.styleFactory( elem );
        elem.seen   = false;

        el.removeAttribute('data-sr');

        el.setAttribute( 'style',
            elem.styles.inline
          + elem.styles.initial
        );
      })

      self.scrolled = self.scrollY();
      self.animate( flag );
    },

    // Applies and removes appropriate styles.
    // @param {boolean} flag — a hook for controlling delay on first load.
    animate: function( flag ){

      var key;
      var elem;
      var visible;

      // Begin element store digest.
      for ( key in self.elems ){
        if ( self.elems.hasOwnProperty( key ) ){

          elem    = self.elems[ key ];
          visible = self.isElemInViewport( elem );

          if ( visible ){

            if ( self.config.delay === 'always'
            || ( self.config.delay === 'onload' && flag )
            || ( self.config.delay === 'once'   && !elem.seen ) ){

              // Use delay.
              elem.domEl.setAttribute( 'style',
                  elem.styles.inline
                + elem.styles.target
                + elem.styles.transition
              );

            } else {

              // Don’t use delay.
              elem.domEl.setAttribute( 'style',
                  elem.styles.inline
                + elem.styles.target
                + elem.styles.reset
              );
            }

            elem.seen = true;

            if ( !elem.config.reset && !elem.animating ){
              elem.animating = true;
              complete( key );
            }

          } else if ( !visible && elem.config.reset ){

            elem.domEl.setAttribute( 'style',
                elem.styles.inline
              + elem.styles.initial
              + elem.styles.reset
            );
          }
        }
      }

      // Digest complete, now un-block the event handler.
      self.blocked = false;

      // Cleans the DOM and removes completed elements from self.elems.
      // @param {integer} key — self.elems property key.
      function complete( key ){

        var elem = self.elems[ key ];

        setTimeout(function(){

          elem.domEl.setAttribute( 'style', elem.styles.inline );
          elem.config.complete( elem.domEl );
          delete self.elems[ key ];

        }, elem.styles.duration );
      }
    },

    // Parses an elements data-sr attribute, and returns a configuration object.
    // @param {object} elem — An object from self.elems.
    // @return {object}
    configFactory: function( elem ){

      var parsed = {};
      var config = {};
      var words  = elem.domEl.getAttribute('data-sr').split( /[, ]+/ );

      words.forEach(function( keyword, i ){
        switch ( keyword ){

          case 'enter':

            parsed.enter = words[ i + 1 ];
            break;

          case 'wait':

            parsed.wait = words[ i + 1 ];
            break;

          case 'move':

            parsed.move = words[ i + 1 ];
            break;

          case 'ease':

            parsed.move = words[ i + 1 ];
            parsed.ease = 'ease';
            break;

          case 'ease-in':

            if ( words[ i + 1 ] == 'up' || words[ i + 1 ] == 'down' ){

              parsed.scale.direction = words[ i + 1 ];
              parsed.scale.power     = words[ i + 2 ];
              parsed.easing          = 'ease-in';
              break;
            }

            parsed.move   = words[ i + 1 ];
            parsed.easing = 'ease-in';
            break;

          case 'ease-in-out':

            if ( words[ i + 1 ] == 'up' || words[ i + 1 ] == 'down' ){

              parsed.scale.direction = words[ i + 1 ];
              parsed.scale.power     = words[ i + 2 ];
              parsed.easing          = 'ease-in-out';
              break;
            }

            parsed.move   = words[ i + 1 ];
            parsed.easing = 'ease-in-out';
            break;

          case 'ease-out':

            if ( words[ i + 1 ] == 'up' || words[ i + 1 ] == 'down' ){

              parsed.scale.direction = words[ i + 1 ];
              parsed.scale.power     = words[ i + 2 ];
              parsed.easing          = 'ease-out';
              break;
            }

            parsed.move   = words[ i + 1 ];
            parsed.easing = 'ease-out';
            break;

          case 'hustle':

            if ( words[ i + 1 ] == 'up' || words[ i + 1 ] == 'down' ){

              parsed.scale.direction = words[ i + 1 ];
              parsed.scale.power     = words[ i + 2 ];
              parsed.easing          = 'cubic-bezier( 0.6, 0.2, 0.1, 1 )';
              break;
            }

            parsed.move   = words[ i + 1 ];
            parsed.easing = 'cubic-bezier( 0.6, 0.2, 0.1, 1 )';
            break;

          case 'over':

            parsed.over = words[ i + 1 ];
            break;

          case 'flip':
          case 'pitch':
            parsed.rotate   = parsed.rotate || {};
            parsed.rotate.x = words[ i + 1 ];
            break;

          case 'spin':
          case 'yaw':
            parsed.rotate   = parsed.rotate || {};
            parsed.rotate.y = words[ i + 1 ];
            break;

          case 'roll':
            parsed.rotate   = parsed.rotate || {};
            parsed.rotate.z = words[ i + 1 ];
            break;

          case 'reset':

            if ( words[ i - 1 ] == 'no' ){
              parsed.reset = false;
            } else {
              parsed.reset = true;
            }
            break;

          case 'scale':

            parsed.scale = {};

            if ( words[ i + 1 ] == 'up' || words[ i + 1 ] == 'down' ){

              parsed.scale.direction = words[ i + 1 ];
              parsed.scale.power     = words[ i + 2 ];
              break;
            }

            parsed.scale.power = words[ i + 1 ];
            break;

          default:
            return;
        }
      });

      // Build default config object, then apply any keywords parsed from the
      // data-sr attribute.
      config = _extend( config, self.config );
      config = _extend( config, parsed );

      if ( config.enter === 'top' || config.enter === 'bottom' ){
        config.axis = 'Y';
      } else if ( config.enter === 'left' || config.enter === 'right' ){
        config.axis = 'X';
      }

      if ( config.easing === 'hustle' ){
        config.easing = 'cubic-bezier( 0.6, 0.2, 0.1, 1 )';
      }

      // Let’s make sure our our pixel distances are negative for top and left.
      // e.g. "enter top and move 25px" starts at 'top: -25px' in CSS.
      if ( config.enter === 'top' || config.enter === 'left' ){
        config.move = '-' + config.move;
      }

      return config;
    },

    // Generates styles based on an elements configuration property.
    // @param {object} elem — An object from self.elems.
    // @return {object}
    styleFactory: function( elem ){

      var inline;
      var initial;
      var reset;
      var target;
      var transition;

      var cfg      = elem.config;
      var duration = ( parseFloat( cfg.over ) + parseFloat( cfg.wait ) ) * 1000;

      // Want to disable delay on mobile devices? Uncomment the line below.
      // if ( self.isMobile() && self.config.mobile ) cfg.wait = 0;

      if ( elem.domEl.getAttribute('style') ){
        inline = elem.domEl.getAttribute('style') + '; visibility: visible; ';
      } else {
        inline = 'visibility: visible; ';
      }

      transition = '-webkit-transition: -webkit-transform ' + cfg.over + ' ' + cfg.easing + ' ' + cfg.wait + ', opacity ' + cfg.over + ' ' + cfg.easing + ' ' + cfg.wait + '; ' +
                           'transition: transform '         + cfg.over + ' ' + cfg.easing + ' ' + cfg.wait + ', opacity ' + cfg.over + ' ' + cfg.easing + ' ' + cfg.wait + '; ' +
                  '-webkit-perspective: 1000;' +
          '-webkit-backface-visibility: hidden;';

      reset      = '-webkit-transition: -webkit-transform ' + cfg.over + ' ' + cfg.easing + ' 0s, opacity ' + cfg.over + ' ' + cfg.easing + ' 0s; ' +
                           'transition: transform '         + cfg.over + ' ' + cfg.easing + ' 0s, opacity ' + cfg.over + ' ' + cfg.easing + ' 0s; ' +
                  '-webkit-perspective: 1000; ' +
          '-webkit-backface-visibility: hidden; ';

      initial = 'transform:';
      target  = 'transform:';
      build();

      // Build again for webkit…
      initial += '-webkit-transform:';
      target  += '-webkit-transform:';
      build();

      return {
        transition: transition,
        initial:    initial,
        target:     target,
        reset:      reset,
        inline:     inline,
        duration:   duration
      };

      // Constructs initial and target styles.
      function build(){

        if ( parseInt( cfg.move ) !== 0 ){
          initial += ' translate' + cfg.axis + '(' + cfg.move + ')';
          target  += ' translate' + cfg.axis + '(0)';
        }

        if ( parseInt( cfg.scale.power ) !== 0 ){

          if ( cfg.scale.direction === 'up' ){
            cfg.scale.value = 1 - ( parseFloat( cfg.scale.power ) * 0.01 );
          } else if ( cfg.scale.direction === 'down' ){
            cfg.scale.value = 1 + ( parseFloat( cfg.scale.power ) * 0.01 );
          }

          initial += ' scale(' + cfg.scale.value + ')';
          target  += ' scale(1)';
        }

        if ( cfg.rotate.x ){
          initial += ' rotateX(' + cfg.rotate.x + ')';
          target  += ' rotateX(0)';
        }

        if ( cfg.rotate.y ){
          initial += ' rotateY(' + cfg.rotate.y + ')';
          target  += ' rotateY(0)';
        }

        if ( cfg.rotate.z ){
          initial += ' rotateZ(' + cfg.rotate.z + ')';
          target  += ' rotateZ(0)';
        }

        initial += '; opacity: ' + cfg.opacity + '; ';
        target  += '; opacity: 1; ';
      }
    },

    getViewportH: function(){

      var client = self.config.viewport['clientHeight'];
      var inner  = window['innerHeight'];

      if ( self.config.viewport === window.document.documentElement ){
        return ( client < inner ) ? inner : client;
      }

      return client;
    },

    scrollY: function(){
      if ( self.config.viewport === window.document.documentElement ){
        return window.pageYOffset;
      } else {
        return self.config.viewport.scrollTop + self.config.viewport.offsetTop;
      }
    },

    getOffset: function( el ){

      var offsetTop  = 0;
      var offsetLeft = 0;

      do {
        if ( !isNaN( el.offsetTop ) ){
          offsetTop  += el.offsetTop;
        }
        if ( !isNaN( el.offsetLeft ) ){
          offsetLeft += el.offsetLeft;
        }
      } while ( el = el.offsetParent );

      return {
        top: offsetTop,
        left: offsetLeft
      };
    },

    isElemInViewport: function( elem ){

      var elHeight = elem.domEl.offsetHeight;
      var elTop    = self.getOffset( elem.domEl ).top;
      var elBottom = elTop + elHeight;
      var vFactor  = elem.config.vFactor || 0;

      return ( confirmBounds() || isPositionFixed() );

      function confirmBounds(){

        var top        = elTop + elHeight * vFactor;
        var bottom     = elBottom - elHeight * vFactor;
        var viewBottom = self.scrolled + self.getViewportH();
        var viewTop    = self.scrolled;

        return ( top < viewBottom ) && ( bottom > viewTop );
      }

      function isPositionFixed(){

        var el    = elem.domEl;
        var style = el.currentStyle || window.getComputedStyle( el, null );

        return style.position === 'fixed';
      }
    },

    isMobile: function(){

      var agent = navigator.userAgent || navigator.vendor || window.opera;

      return (/(ipad|playbook|silk|android|bb\d+|meego).+mobile|avantgo|bada\/|blackberry|blazer|compal|elaine|fennec|hiptop|iemobile|ip(hone|od)|iris|kindle|lge |maemo|midp|mmp|mobile.+firefox|netfront|opera m(ob|in)i|palm( os)?|phone|p(ixi|re)\/|plucker|pocket|psp|series(4|6)0|symbian|treo|up\.(browser|link)|vodafone|wap|windows (ce|phone)|xda|xiino/i.test( agent )||/1207|6310|6590|3gso|4thp|50[1-6]i|770s|802s|a wa|abac|ac(er|oo|s\-)|ai(ko|rn)|al(av|ca|co)|amoi|an(ex|ny|yw)|aptu|ar(ch|go)|as(te|us)|attw|au(di|\-m|r |s )|avan|be(ck|ll|nq)|bi(lb|rd)|bl(ac|az)|br(e|v)w|bumb|bw\-(n|u)|c55\/|capi|ccwa|cdm\-|cell|chtm|cldc|cmd\-|co(mp|nd)|craw|da(it|ll|ng)|dbte|dc\-s|devi|dica|dmob|do(c|p)o|ds(12|\-d)|el(49|ai)|em(l2|ul)|er(ic|k0)|esl8|ez([4-7]0|os|wa|ze)|fetc|fly(\-|_)|g1 u|g560|gene|gf\-5|g\-mo|go(\.w|od)|gr(ad|un)|haie|hcit|hd\-(m|p|t)|hei\-|hi(pt|ta)|hp( i|ip)|hs\-c|ht(c(\-| |_|a|g|p|s|t)|tp)|hu(aw|tc)|i\-(20|go|ma)|i230|iac( |\-|\/)|ibro|idea|ig01|ikom|im1k|inno|ipaq|iris|ja(t|v)a|jbro|jemu|jigs|kddi|keji|kgt( |\/)|klon|kpt |kwc\-|kyo(c|k)|le(no|xi)|lg( g|\/(k|l|u)|50|54|\-[a-w])|libw|lynx|m1\-w|m3ga|m50\/|ma(te|ui|xo)|mc(01|21|ca)|m\-cr|me(rc|ri)|mi(o8|oa|ts)|mmef|mo(01|02|bi|de|do|t(\-| |o|v)|zz)|mt(50|p1|v )|mwbp|mywa|n10[0-2]|n20[2-3]|n30(0|2)|n50(0|2|5)|n7(0(0|1)|10)|ne((c|m)\-|on|tf|wf|wg|wt)|nok(6|i)|nzph|o2im|op(ti|wv)|oran|owg1|p800|pan(a|d|t)|pdxg|pg(13|\-([1-8]|c))|phil|pire|pl(ay|uc)|pn\-2|po(ck|rt|se)|prox|psio|pt\-g|qa\-a|qc(07|12|21|32|60|\-[2-7]|i\-)|qtek|r380|r600|raks|rim9|ro(ve|zo)|s55\/|sa(ge|ma|mm|ms|ny|va)|sc(01|h\-|oo|p\-)|sdk\/|se(c(\-|0|1)|47|mc|nd|ri)|sgh\-|shar|sie(\-|m)|sk\-0|sl(45|id)|sm(al|ar|b3|it|t5)|so(ft|ny)|sp(01|h\-|v\-|v )|sy(01|mb)|t2(18|50)|t6(00|10|18)|ta(gt|lk)|tcl\-|tdg\-|tel(i|m)|tim\-|t\-mo|to(pl|sh)|ts(70|m\-|m3|m5)|tx\-9|up(\.b|g1|si)|utst|v400|v750|veri|vi(rg|te)|vk(40|5[0-3]|\-v)|vm40|voda|vulc|vx(52|53|60|61|70|80|81|83|85|98)|w3c(\-| )|webc|whit|wi(g |nc|nw)|wmlb|wonu|x700|yas\-|your|zeto|zte\-/i.test( agent.substr( 0, 4 ))) ? true : false;
    },

    isSupported: function(){

      var sensor    = document.createElement('sensor');
      var cssPrefix = 'Webkit,Moz,O,'.split(',');
      var tests     = ( 'transition ' + cssPrefix.join('transition,') ).split(',');

      for ( var i = 0; i < tests.length; i++ ){
        if ( !sensor.style[tests[i]] === '' ){
          return false;
        }
      }

      return true;
    },

    destroy: function(){

      var node = self.config.viewport;
      var query = Array.prototype.slice.call( node.querySelectorAll('[data-sr]') );

      query.forEach(function( el ){
        el.removeAttribute('data-sr');
      });
    }
  } // End of the scrollReveal prototype ======================================|

  _handler = function( e ){

    if ( !self.blocked ){

      self.blocked  = true;
      self.scrolled = self.scrollY();

      _requestAnimFrame(function(){
        self.animate();
      });
    }
  }

  _extend = function( target, src ){

    for ( var prop in src ){
      if ( src.hasOwnProperty( prop ) ){
        target[ prop ] = src[ prop ];
      }
    }

    return target;
  }

  // RequestAnimationFrame polyfill.
  _requestAnimFrame = (function(){

    return window.requestAnimationFrame        ||
           window.webkitRequestAnimationFrame  ||
           window.mozRequestAnimationFrame     ||

          function( callback ){
            window.setTimeout( callback, 1000 / 60 );
          };
  }());

  return scrollReveal;

})( window );

return scrollReveal;

}));
