iframeResizer.contentWindow.js

/*
 * File: iframeResizer.contentWindow.js
 * Desc: Include this file in any page being loaded into an iframe
 *       to force the iframe to resize to the content size.
 * Requires: iframeResizer.js on host page.
 * Doc: https://github.com/davidjbradshaw/iframe-resizer
 * Author: David J. Bradshaw - dave@bradshaw.net
 * Contributor: Jure Mav - jure.mav@gmail.com
 * Contributor: Ian Caunce - ian@hallnet.co.uk
 */


;(function(undefined) {
  'use strict';

  if(typeof window === 'undefined') return; // don't run for server side render

  var
    autoResize            = true,
    base                  = 10,
    bodyBackground        = '',
    bodyMargin            = 0,
    bodyMarginStr         = '',
    bodyObserver          = null,
    bodyPadding           = '',
    calculateWidth        = false,
    doubleEventList       = {'resize':1,'click':1},
    eventCancelTimer      = 128,
    firstRun              = true,
    height                = 1,
    heightCalcModeDefault = 'bodyOffset',
    heightCalcMode        = heightCalcModeDefault,
    initLock              = true,
    initMsg               = '',
    inPageLinks           = {},
    interval              = 32,
    intervalTimer         = null,
    logging               = false,
    msgID                 = '[iFrameSizer]',  //Must match host page msg ID
    msgIdLen              = msgID.length,
    myID                  = '',
    observer              = null,
    resetRequiredMethods  = {max:1,min:1,bodyScroll:1,documentElementScroll:1},
    resizeFrom            = 'child',
    sendPermit            = true,
    target                = window.parent,
    targetOriginDefault   = '*',
    tolerance             = 0,
    triggerLocked         = false,
    triggerLockedTimer    = null,
    throttledTimer        = 16,
    width                 = 1,
    widthCalcModeDefault  = 'scroll',
    widthCalcMode         = widthCalcModeDefault,
    win                   = window,
    messageCallback       = function() { warn('MessageCallback function not defined'); },
    readyCallback         = function() {},
    pageInfoCallback      = function() {},
    customCalcMethods     = {
      height: function() {
        warn('Custom height calculation function not defined');
        return document.documentElement.offsetHeight;
      },
      width: function() {
        warn('Custom width calculation function not defined');
        return document.body.scrollWidth;
      }
    },
    eventHandlersByName   = {};


  function addEventListener(el,evt,func) {
    /* istanbul ignore else */ // Not testable in phantonJS
    if ('addEventListener' in window) {
      el.addEventListener(evt,func, false);
    } else if ('attachEvent' in window) { //IE
      el.attachEvent('on'+evt,func);
    }
  }

  function removeEventListener(el,evt,func) {
    /* istanbul ignore else */ // Not testable in phantonJS
    if ('removeEventListener' in window) {
      el.removeEventListener(evt,func, false);
    } else if ('detachEvent' in window) { //IE
      el.detachEvent('on'+evt,func);
    }
  }

  function capitalizeFirstLetter(string) {
    return string.charAt(0).toUpperCase() + string.slice(1);
  }

  //Based on underscore.js
  function throttle(func) {
    var
      context, args, result,
      timeout = null,
      previous = 0,
      later = function() {
        previous = getNow();
        timeout = null;
        result = func.apply(context, args);
        if (!timeout) {
          context = args = null;
        }
      };

    return function() {
      var now = getNow();

      if (!previous) {
        previous = now;
      }

      var remaining = throttledTimer - (now - previous);

      context = this;
      args = arguments;

      if (remaining <= 0 || remaining > throttledTimer) {
        if (timeout) {
          clearTimeout(timeout);
          timeout = null;
        }

        previous = now;
        result = func.apply(context, args);

        if (!timeout) {
          context = args = null;
        }

      } else if (!timeout) {
        timeout = setTimeout(later, remaining);
      }

      return result;
    };
  }

  var getNow = Date.now || function() {
    /* istanbul ignore next */ // Not testable in PhantonJS
    return new Date().getTime();
  };

  function formatLogMsg(msg) {
    return msgID + '[' + myID + ']' + ' ' + msg;
  }

  function log(msg) {
    if (logging && ('object' === typeof window.console)) {
      console.log(formatLogMsg(msg));
    }
  }

  function warn(msg) {
    if ('object' === typeof window.console) {
      console.warn(formatLogMsg(msg));
    }
  }


  function init() {
    readDataFromParent();
    log('Initialising iFrame ('+location.href+')');
    readDataFromPage();
    setMargin();
    setBodyStyle('background',bodyBackground);
    setBodyStyle('padding',bodyPadding);
    injectClearFixIntoBodyElement();
    checkHeightMode();
    checkWidthMode();
    stopInfiniteResizingOfIFrame();
    setupPublicMethods();
    startEventListeners();
    inPageLinks = setupInPageLinks();
    sendSize('init','Init message from host page');
    readyCallback();
  }

  function readDataFromParent() {

    function strBool(str) {
      return 'true' === str ? true : false;
    }

    var data = initMsg.substr(msgIdLen).split(':');

    myID               = data[0];
    bodyMargin         = (undefined !== data[1]) ? Number(data[1])   : bodyMargin; //For V1 compatibility
    calculateWidth     = (undefined !== data[2]) ? strBool(data[2])  : calculateWidth;
    logging            = (undefined !== data[3]) ? strBool(data[3])  : logging;
    interval           = (undefined !== data[4]) ? Number(data[4])   : interval;
    autoResize         = (undefined !== data[6]) ? strBool(data[6])  : autoResize;
    bodyMarginStr      = data[7];
    heightCalcMode     = (undefined !== data[8]) ? data[8]           : heightCalcMode;
    bodyBackground     = data[9];
    bodyPadding        = data[10];
    tolerance          = (undefined !== data[11]) ? Number(data[11]) : tolerance;
    inPageLinks.enable = (undefined !== data[12]) ? strBool(data[12]): false;
    resizeFrom         = (undefined !== data[13]) ? data[13]         : resizeFrom;
    widthCalcMode      = (undefined !== data[14]) ? data[14]         : widthCalcMode;
  }

  function readDataFromPage() {
    function readData() {
      var data = window.iFrameResizer;

      log('Reading data from page: ' + JSON.stringify(data));

      messageCallback     = ('messageCallback'         in data) ? data.messageCallback         : messageCallback;
      readyCallback       = ('readyCallback'           in data) ? data.readyCallback           : readyCallback;
      targetOriginDefault = ('targetOrigin'            in data) ? data.targetOrigin            : targetOriginDefault;
      heightCalcMode      = ('heightCalculationMethod' in data) ? data.heightCalculationMethod : heightCalcMode;
      widthCalcMode       = ('widthCalculationMethod'  in data) ? data.widthCalculationMethod  : widthCalcMode;
    }

    function setupCustomCalcMethods(calcMode, calcFunc) {
      if ('function' === typeof calcMode) {
        log('Setup custom ' + calcFunc + 'CalcMethod');
        customCalcMethods[calcFunc] = calcMode;
        calcMode = 'custom';
      }

      return calcMode;
    }

    if(('iFrameResizer' in window) && (Object === window.iFrameResizer.constructor)) {
      readData();
      heightCalcMode = setupCustomCalcMethods(heightCalcMode, 'height');
      widthCalcMode  = setupCustomCalcMethods(widthCalcMode,  'width');
    }

    log('TargetOrigin for parent set to: ' + targetOriginDefault);
  }


  function chkCSS(attr,value) {
    if (-1 !== value.indexOf('-')) {
      warn('Negative CSS value ignored for '+attr);
      value='';
    }
    return value;
  }

  function setBodyStyle(attr,value) {
    if ((undefined !== value) && ('' !== value) && ('null' !== value)) {
      document.body.style[attr] = value;
      log('Body '+attr+' set to "'+value+'"');
    }
  }

  function setMargin() {
    //If called via V1 script, convert bodyMargin from int to str
    if (undefined === bodyMarginStr) {
      bodyMarginStr = bodyMargin+'px';
    }

    setBodyStyle('margin',chkCSS('margin',bodyMarginStr));
  }

  function stopInfiniteResizingOfIFrame() {
    document.documentElement.style.height = '';
    document.body.style.height = '';
    log('HTML & body height set to "auto"');
  }


  function manageTriggerEvent(options) {

    var listener = {
      add:    function(eventName) {
        function handleEvent() {
          sendSize(options.eventName,options.eventType);
        }

        eventHandlersByName[eventName] = handleEvent;

        addEventListener(window,eventName,handleEvent);
      },
      remove: function(eventName) {
        var handleEvent = eventHandlersByName[eventName];
        delete eventHandlersByName[eventName];

        removeEventListener(window,eventName,handleEvent);
      }
    };

    if(options.eventNames && Array.prototype.map) {
      options.eventName = options.eventNames[0];
      options.eventNames.map(listener[options.method]);
    } else {
      listener[options.method](options.eventName);
    }

    log(capitalizeFirstLetter(options.method) + ' event listener: ' + options.eventType);
  }

  function manageEventListeners(method) {
    manageTriggerEvent({method:method, eventType: 'Animation Start',           eventNames: ['animationstart','webkitAnimationStart'] });
    manageTriggerEvent({method:method, eventType: 'Animation Iteration',       eventNames: ['animationiteration','webkitAnimationIteration'] });
    manageTriggerEvent({method:method, eventType: 'Animation End',             eventNames: ['animationend','webkitAnimationEnd'] });
    manageTriggerEvent({method:method, eventType: 'Input',                     eventName:  'input' });
    manageTriggerEvent({method:method, eventType: 'Mouse Up',                  eventName:  'mouseup' });
    manageTriggerEvent({method:method, eventType: 'Mouse Down',                eventName:  'mousedown' });
    manageTriggerEvent({method:method, eventType: 'Orientation Change',        eventName:  'orientationchange' });
    manageTriggerEvent({method:method, eventType: 'Print',                     eventName:  ['afterprint', 'beforeprint'] });
    manageTriggerEvent({method:method, eventType: 'Ready State Change',        eventName:  'readystatechange' });
    manageTriggerEvent({method:method, eventType: 'Touch Start',               eventName:  'touchstart' });
    manageTriggerEvent({method:method, eventType: 'Touch End',                 eventName:  'touchend' });
    manageTriggerEvent({method:method, eventType: 'Touch Cancel',              eventName:  'touchcancel' });
    manageTriggerEvent({method:method, eventType: 'Transition Start',          eventNames: ['transitionstart','webkitTransitionStart','MSTransitionStart','oTransitionStart','otransitionstart'] });
    manageTriggerEvent({method:method, eventType: 'Transition Iteration',      eventNames: ['transitioniteration','webkitTransitionIteration','MSTransitionIteration','oTransitionIteration','otransitioniteration'] });
    manageTriggerEvent({method:method, eventType: 'Transition End',            eventNames: ['transitionend','webkitTransitionEnd','MSTransitionEnd','oTransitionEnd','otransitionend'] });
    if('child' === resizeFrom) {
      manageTriggerEvent({method:method, eventType: 'IFrame Resized',        eventName:  'resize' });
    }
  }

  function checkCalcMode(calcMode,calcModeDefault,modes,type) {
    if (calcModeDefault !== calcMode) {
      if (!(calcMode in modes)) {
        warn(calcMode + ' is not a valid option for '+type+'CalculationMethod.');
        calcMode=calcModeDefault;
      }
      log(type+' calculation method set to "'+calcMode+'"');
    }

    return calcMode;
  }

  function checkHeightMode() {
    heightCalcMode = checkCalcMode(heightCalcMode,heightCalcModeDefault,getHeight,'height');
  }

  function checkWidthMode() {
    widthCalcMode = checkCalcMode(widthCalcMode,widthCalcModeDefault,getWidth,'width');
  }

  function startEventListeners() {
    if ( true === autoResize ) {
      manageEventListeners('add');
      setupMutationObserver();
    }
    else {
      log('Auto Resize disabled');
    }
  }

  function stopMsgsToParent() {
    log('Disable outgoing messages');
    sendPermit = false;
  }

  function removeMsgListener() {
    log('Remove event listener: Message');
    removeEventListener(window, 'message', receiver);
  }

  function disconnectMutationObserver() {
    if (null !== bodyObserver) {
      /* istanbul ignore next */ // Not testable in PhantonJS
      bodyObserver.disconnect();
    }
  }

  function stopEventListeners() {
    manageEventListeners('remove');
    disconnectMutationObserver();
    clearInterval(intervalTimer);
  }

  function teardown() {
    stopMsgsToParent();
    removeMsgListener();
    if (true === autoResize) stopEventListeners();
  }

  function injectClearFixIntoBodyElement() {
    var clearFix = document.createElement('div');
    clearFix.style.clear   = 'both';
    clearFix.style.display = 'block'; //Guard against this having been globally redefined in CSS.
    document.body.appendChild(clearFix);
  }

  function setupInPageLinks() {

    function getPagePosition () {
      return {
        x: (window.pageXOffset !== undefined) ? window.pageXOffset : document.documentElement.scrollLeft,
        y: (window.pageYOffset !== undefined) ? window.pageYOffset : document.documentElement.scrollTop
      };
    }

    function getElementPosition(el) {
      var
        elPosition   = el.getBoundingClientRect(),
        pagePosition = getPagePosition();

      return {
        x: parseInt(elPosition.left,10) + parseInt(pagePosition.x,10),
        y: parseInt(elPosition.top,10)  + parseInt(pagePosition.y,10)
      };
    }

    function findTarget(location) {
      function jumpToTarget(target) {
        var jumpPosition = getElementPosition(target);

        log('Moving to in page link (#'+hash+') at x: '+jumpPosition.x+' y: '+jumpPosition.y);
        sendMsg(jumpPosition.y, jumpPosition.x, 'scrollToOffset'); // X&Y reversed at sendMsg uses height/width
      }

      var
        hash     = location.split('#')[1] || location, //Remove # if present
        hashData = decodeURIComponent(hash),
        target   = document.getElementById(hashData) || document.getElementsByName(hashData)[0];

      if (undefined !== target) {
        jumpToTarget(target);
      } else {
        log('In page link (#' + hash + ') not found in iFrame, so sending to parent');
        sendMsg(0,0,'inPageLink','#'+hash);
      }
    }

    function checkLocationHash() {
      if ('' !== location.hash && '#' !== location.hash) {
        findTarget(location.href);
      }
    }

    function bindAnchors() {
      function setupLink(el) {
        function linkClicked(e) {
          e.preventDefault();

          /*jshint validthis:true */
          findTarget(this.getAttribute('href'));
        }

        if ('#' !== el.getAttribute('href')) {
          addEventListener(el,'click',linkClicked);
        }
      }

      Array.prototype.forEach.call( document.querySelectorAll( 'a[href^="#"]' ), setupLink );
    }

    function bindLocationHash() {
      addEventListener(window,'hashchange',checkLocationHash);
    }

    function initCheck() { //check if page loaded with location hash after init resize
      setTimeout(checkLocationHash,eventCancelTimer);
    }

    function enableInPageLinks() {
      /* istanbul ignore else */ // Not testable in phantonJS
      if(Array.prototype.forEach && document.querySelectorAll) {
        log('Setting up location.hash handlers');
        bindAnchors();
        bindLocationHash();
        initCheck();
      } else {
        warn('In page linking not fully supported in this browser! (See README.md for IE8 workaround)');
      }
    }

    if(inPageLinks.enable) {
      enableInPageLinks();
    } else {
      log('In page linking not enabled');
    }

    return {
      findTarget:findTarget
    };
  }

  function setupPublicMethods() {
    log('Enable public methods');

    win.parentIFrame = {

      autoResize: function autoResizeF(resize) {
        if (true === resize && false === autoResize) {
          autoResize=true;
          startEventListeners();
          //sendSize('autoResize','Auto Resize enabled');
        } else if (false === resize && true === autoResize) {
          autoResize=false;
          stopEventListeners();
        }

        return autoResize;
      },

      close: function closeF() {
        sendMsg(0,0,'close');
        teardown();
      },

      getId: function getIdF() {
        return myID;
      },

      getPageInfo: function getPageInfoF(callback) {
        if ('function' === typeof callback) {
          pageInfoCallback = callback;
          sendMsg(0,0,'pageInfo');
        } else {
          pageInfoCallback = function() {};
          sendMsg(0,0,'pageInfoStop');
        }
      },

      moveToAnchor: function moveToAnchorF(hash) {
        inPageLinks.findTarget(hash);
      },

      reset: function resetF() {
        resetIFrame('parentIFrame.reset');
      },

      scrollTo: function scrollToF(x,y) {
        sendMsg(y,x,'scrollTo'); // X&Y reversed at sendMsg uses height/width
      },

      scrollToOffset: function scrollToF(x,y) {
        sendMsg(y,x,'scrollToOffset'); // X&Y reversed at sendMsg uses height/width
      },

      sendMessage: function sendMessageF(msg,targetOrigin) {
        sendMsg(0,0,'message',JSON.stringify(msg),targetOrigin);
      },

      setHeightCalculationMethod: function setHeightCalculationMethodF(heightCalculationMethod) {
        heightCalcMode = heightCalculationMethod;
        checkHeightMode();
      },

      setWidthCalculationMethod: function setWidthCalculationMethodF(widthCalculationMethod) {
        widthCalcMode = widthCalculationMethod;
        checkWidthMode();
      },

      setTargetOrigin: function setTargetOriginF(targetOrigin) {
        log('Set targetOrigin: '+targetOrigin);
        targetOriginDefault = targetOrigin;
      },

      size: function sizeF(customHeight, customWidth) {
        var valString = ''+(customHeight?customHeight:'')+(customWidth?','+customWidth:'');
        //lockTrigger();
        sendSize('size','parentIFrame.size('+valString+')', customHeight, customWidth);
      }
    };
  }

  function initInterval() {
    if ( 0 !== interval ) {
      log('setInterval: '+interval+'ms');
      intervalTimer = setInterval(function() {
        sendSize('interval','setInterval: '+interval);
      },Math.abs(interval));
    }
  }

  /* istanbul ignore next */  //Not testable in PhantomJS
  function setupBodyMutationObserver() {
    function addImageLoadListners(mutation) {
      function addImageLoadListener(element) {
        if (false === element.complete) {
          log('Attach listeners to ' + element.src);
          element.addEventListener('load', imageLoaded, false);
          element.addEventListener('error', imageError, false);
          elements.push(element);
        }
      }

      if (mutation.type === 'attributes' && mutation.attributeName === 'src') {
        addImageLoadListener(mutation.target);
      } else if (mutation.type === 'childList') {
        Array.prototype.forEach.call(
          mutation.target.querySelectorAll('img'),
          addImageLoadListener
        );
      }
    }

    function removeFromArray(element) {
      elements.splice(elements.indexOf(element),1);
    }

    function removeImageLoadListener(element) {
      log('Remove listeners from ' + element.src);
      element.removeEventListener('load', imageLoaded, false);
      element.removeEventListener('error', imageError, false);
      removeFromArray(element);
    }

    function imageEventTriggered(event,type,typeDesc) {
      removeImageLoadListener(event.target);
      sendSize(type, typeDesc + ': ' + event.target.src, undefined, undefined);
    }

    function imageLoaded(event) {
      imageEventTriggered(event,'imageLoad','Image loaded');
    }

    function imageError(event) {
      imageEventTriggered(event,'imageLoadFailed','Image load failed');
    }

    function mutationObserved(mutations) {
      sendSize('mutationObserver','mutationObserver: ' + mutations[0].target + ' ' + mutations[0].type);

      //Deal with WebKit asyncing image loading when tags are injected into the page
      mutations.forEach(addImageLoadListners);
    }

    function createMutationObserver() {
      var
        target = document.querySelector('body'),

        config = {
          attributes            : true,
          attributeOldValue     : false,
          characterData         : true,
          characterDataOldValue : false,
          childList             : true,
          subtree               : true
        };

      observer = new MutationObserver(mutationObserved);

      log('Create body MutationObserver');
      observer.observe(target, config);

      return observer;
    }

    var
      elements         = [],
      MutationObserver = window.MutationObserver || window.WebKitMutationObserver,
      observer         = createMutationObserver();

    return {
      disconnect: function () {
        if ('disconnect' in observer) {
          log('Disconnect body MutationObserver');
          observer.disconnect();
          elements.forEach(removeImageLoadListener);
        }
      }
    };
  }

  function setupMutationObserver() {
    var	forceIntervalTimer = 0 > interval;

    /* istanbul ignore if */ // Not testable in PhantomJS
    if (window.MutationObserver || window.WebKitMutationObserver) {
      if (forceIntervalTimer) {
        initInterval();
      } else {
        bodyObserver = setupBodyMutationObserver();
      }
    } else {
      log('MutationObserver not supported in this browser!');
      initInterval();
    }
  }


  // document.documentElement.offsetHeight is not reliable, so
  // we have to jump through hoops to get a better value.
  function getComputedStyle(prop,el) {
    /* istanbul ignore next */  //Not testable in PhantomJS
    function convertUnitsToPxForIE8(value) {
      var PIXEL = /^\d+(px)?$/i;

      if (PIXEL.test(value)) {
        return parseInt(value,base);
      }

      var
        style = el.style.left,
        runtimeStyle = el.runtimeStyle.left;

      el.runtimeStyle.left = el.currentStyle.left;
      el.style.left = value || 0;
      value = el.style.pixelLeft;
      el.style.left = style;
      el.runtimeStyle.left = runtimeStyle;

      return value;
    }

    var retVal = 0;
    el =  el || document.body;

    /* istanbul ignore else */ // Not testable in phantonJS
    if (('defaultView' in document) && ('getComputedStyle' in document.defaultView)) {
      retVal = document.defaultView.getComputedStyle(el, null);
      retVal = (null !== retVal) ? retVal[prop] : 0;
    } else {//IE8
      retVal =  convertUnitsToPxForIE8(el.currentStyle[prop]);
    }

    return parseInt(retVal,base);
  }

  function chkEventThottle(timer) {
    if(timer > throttledTimer/2) {
      throttledTimer = 2*timer;
      log('Event throttle increased to ' + throttledTimer + 'ms');
    }
  }

  //Idea from https://github.com/guardian/iframe-messenger
  function getMaxElement(side,elements) {
    var
      elementsLength = elements.length,
      elVal          = 0,
      maxVal         = 0,
      Side           = capitalizeFirstLetter(side),
      timer          = getNow();

    for (var i = 0; i < elementsLength; i++) {
      elVal = elements[i].getBoundingClientRect()[side] + getComputedStyle('margin'+Side,elements[i]);
      if (elVal > maxVal) {
        maxVal = elVal;
      }
    }

    timer = getNow() - timer;

    log('Parsed '+elementsLength+' HTML elements');
    log('Element position calculated in ' + timer + 'ms');

    chkEventThottle(timer);

    return maxVal;
  }

  function getAllMeasurements(dimention) {
    return [
      dimention.bodyOffset(),
      dimention.bodyScroll(),
      dimention.documentElementOffset(),
      dimention.documentElementScroll()
    ];
  }

  function getTaggedElements(side,tag) {
    function noTaggedElementsFound() {
      warn('No tagged elements ('+tag+') found on page');
      return document.querySelectorAll('body *');
    }

    var elements = document.querySelectorAll('['+tag+']');

    if (0 === elements.length) noTaggedElementsFound();

    return getMaxElement(side,elements);
  }

  function getAllElements() {
    return document.querySelectorAll('body *');
  }

  var
    getHeight = {
      bodyOffset: function getBodyOffsetHeight() {
        return  document.body.offsetHeight + getComputedStyle('marginTop') + getComputedStyle('marginBottom');
      },

      offset: function() {
        return getHeight.bodyOffset(); //Backwards compatability
      },

      bodyScroll: function getBodyScrollHeight() {
        return document.body.scrollHeight;
      },

      custom: function getCustomWidth() {
        return customCalcMethods.height();
      },

      documentElementOffset: function getDEOffsetHeight() {
        return document.documentElement.offsetHeight;
      },

      documentElementScroll: function getDEScrollHeight() {
        return document.documentElement.scrollHeight;
      },

      max: function getMaxHeight() {
        return Math.max.apply(null,getAllMeasurements(getHeight));
      },

      min: function getMinHeight() {
        return Math.min.apply(null,getAllMeasurements(getHeight));
      },

      grow: function growHeight() {
        return getHeight.max(); //Run max without the forced downsizing
      },

      lowestElement: function getBestHeight() {
        return Math.max(getHeight.bodyOffset() || getHeight.documentElementOffset(), getMaxElement('bottom',getAllElements()));
      },

      taggedElement: function getTaggedElementsHeight() {
        return getTaggedElements('bottom','data-iframe-height');
      }
    },

    getWidth = {
      bodyScroll: function getBodyScrollWidth() {
        return document.body.scrollWidth;
      },

      bodyOffset: function getBodyOffsetWidth() {
        return document.body.offsetWidth;
      },

      custom: function getCustomWidth() {
        return customCalcMethods.width();
      },

      documentElementScroll: function getDEScrollWidth() {
        return document.documentElement.scrollWidth;
      },

      documentElementOffset: function getDEOffsetWidth() {
        return document.documentElement.offsetWidth;
      },

      scroll: function getMaxWidth() {
        return Math.max(getWidth.bodyScroll(), getWidth.documentElementScroll());
      },

      max: function getMaxWidth() {
        return Math.max.apply(null,getAllMeasurements(getWidth));
      },

      min: function getMinWidth() {
        return Math.min.apply(null,getAllMeasurements(getWidth));
      },

      rightMostElement: function rightMostElement() {
        return getMaxElement('right', getAllElements());
      },

      taggedElement: function getTaggedElementsWidth() {
        return getTaggedElements('right', 'data-iframe-width');
      }
    };


  function sizeIFrame(triggerEvent, triggerEventDesc, customHeight, customWidth) {

    function resizeIFrame() {
      height = currentHeight;
      width  = currentWidth;

      sendMsg(height,width,triggerEvent);
    }

    function isSizeChangeDetected() {
      function checkTolarance(a,b) {
        var retVal = Math.abs(a-b) <= tolerance;
        return !retVal;
      }

      currentHeight = (undefined !== customHeight)  ? customHeight : getHeight[heightCalcMode]();
      currentWidth  = (undefined !== customWidth )  ? customWidth  : getWidth[widthCalcMode]();

      return	checkTolarance(height,currentHeight) || (calculateWidth && checkTolarance(width,currentWidth));
    }

    function isForceResizableEvent() {
      return !(triggerEvent in {'init':1,'interval':1,'size':1});
    }

    function isForceResizableCalcMode() {
      return (heightCalcMode in resetRequiredMethods) || (calculateWidth && widthCalcMode in resetRequiredMethods);
    }

    function logIgnored() {
      log('No change in size detected');
    }

    function checkDownSizing() {
      if (isForceResizableEvent() && isForceResizableCalcMode()) {
        resetIFrame(triggerEventDesc);
      } else if (!(triggerEvent in {'interval':1})) {
        logIgnored();
      }
    }

    var	currentHeight,currentWidth;

    if (isSizeChangeDetected() || 'init' === triggerEvent) {
      lockTrigger();
      resizeIFrame();
    } else {
      checkDownSizing();
    }
  }

  var sizeIFrameThrottled = throttle(sizeIFrame);

  function sendSize(triggerEvent, triggerEventDesc, customHeight, customWidth) {
    function recordTrigger() {
      if (!(triggerEvent in {'reset':1,'resetPage':1,'init':1})) {
        log( 'Trigger event: ' + triggerEventDesc );
      }
    }

    function isDoubleFiredEvent() {
      return  triggerLocked && (triggerEvent in doubleEventList);
    }

    if (!isDoubleFiredEvent()) {
      recordTrigger();
      if (triggerEvent === 'init') {
        sizeIFrame(triggerEvent, triggerEventDesc, customHeight, customWidth);
      } else {
        sizeIFrameThrottled(triggerEvent, triggerEventDesc, customHeight, customWidth);
      }
    } else {
      log('Trigger event cancelled: '+triggerEvent);
    }
  }

  function lockTrigger() {
    if (!triggerLocked) {
      triggerLocked = true;
      log('Trigger event lock on');
    }
    clearTimeout(triggerLockedTimer);
    triggerLockedTimer = setTimeout(function() {
      triggerLocked = false;
      log('Trigger event lock off');
      log('--');
    },eventCancelTimer);
  }

  function triggerReset(triggerEvent) {
    height = getHeight[heightCalcMode]();
    width  = getWidth[widthCalcMode]();

    sendMsg(height,width,triggerEvent);
  }

  function resetIFrame(triggerEventDesc) {
    var hcm = heightCalcMode;
    heightCalcMode = heightCalcModeDefault;

    log('Reset trigger event: ' + triggerEventDesc);
    lockTrigger();
    triggerReset('reset');

    heightCalcMode = hcm;
  }

  function sendMsg(height,width,triggerEvent,msg,targetOrigin) {
    function setTargetOrigin() {
      if (undefined === targetOrigin) {
        targetOrigin = targetOriginDefault;
      } else {
        log('Message targetOrigin: '+targetOrigin);
      }
    }

    function sendToParent() {
      var
        size  = height + ':' + width,
        message = myID + ':' +  size + ':' + triggerEvent + (undefined !== msg ? ':' + msg : '');

      log('Sending message to host page (' + message + ')');
      target.postMessage( msgID + message, targetOrigin);
    }

    if(true === sendPermit) {
      setTargetOrigin();
      sendToParent();
    }
  }

  function receiver(event) {
    var processRequestFromParent = {
      init: function initFromParent() {
        function fireInit() {
          initMsg = event.data;
          target  = event.source;

          init();
          firstRun = false;
          setTimeout(function() { initLock = false;},eventCancelTimer);
        }

        if (document.readyState === "interactive" || document.readyState === "complete") {
          fireInit();
        } else {
          log('Waiting for page ready');
          addEventListener(window,'readystatechange',processRequestFromParent.initFromParent);
        }
      },

      reset: function resetFromParent() {
        if (!initLock) {
          log('Page size reset by host page');
          triggerReset('resetPage');
        } else {
          log('Page reset ignored by init');
        }
      },

      resize: function resizeFromParent() {
        sendSize('resizeParent','Parent window requested size check');
      },

      moveToAnchor: function moveToAnchorF() {
        inPageLinks.findTarget(getData());
      },
      inPageLink: function inPageLinkF() {this.moveToAnchor();}, //Backward compatability

      pageInfo: function pageInfoFromParent() {
        var msgBody = getData();
        log('PageInfoFromParent called from parent: ' + msgBody );
        pageInfoCallback(JSON.parse(msgBody));
        log(' --');
      },

      message: function messageFromParent() {
        var msgBody = getData();

        log('MessageCallback called from parent: ' + msgBody );
        messageCallback(JSON.parse(msgBody));
        log(' --');
      }
    };

    function isMessageForUs() {
      return msgID === (''+event.data).substr(0,msgIdLen); //''+ Protects against non-string messages
    }

    function getMessageType() {
      return event.data.split(']')[1].split(':')[0];
    }

    function getData() {
      return event.data.substr(event.data.indexOf(':')+1);
    }

    function isMiddleTier() {
      return !(typeof module !== 'undefined' && module.exports) && ('iFrameResize' in window);
    }

    function isInitMsg() {
      //Test if this message is from a child below us. This is an ugly test, however, updating
      //the message format would break backwards compatibity.
      return event.data.split(':')[2] in {'true':1,'false':1};
    }

    function callFromParent() {
      var messageType = getMessageType();

      if (messageType in processRequestFromParent) {
        processRequestFromParent[messageType]();
      } else if (!isMiddleTier() && !isInitMsg()) {
        warn('Unexpected message ('+event.data+')');
      }
    }

    function processMessage() {
      if (false === firstRun) {
        callFromParent();
      } else if (isInitMsg()) {
        processRequestFromParent.init();
      } else {
        log('Ignored message of type "' + getMessageType() + '". Received before initialization.');
      }
    }

    if (isMessageForUs()) {
      processMessage();
    }
  }

  //Normally the parent kicks things off when it detects the iFrame has loaded.
  //If this script is async-loaded, then tell parent page to retry init.
  function chkLateLoaded() {
    if('loading' !== document.readyState) {
      window.parent.postMessage('[iFrameResizerChild]Ready','*');
    }
  }

  addEventListener(window, 'message', receiver);
  chkLateLoaded();

  

})();