/**
* tbframe.js
* Taboola frame injector
* 23 Feb 2014
* Effie NAdiv
*/
(function () {
"use strict";
var MAX_INT = 2147483648,
publisher,
currentQueue = [],
processTimer,
QUEUE_PROCESS_INTERVAL = 20,
reIsAbsolute = /^(https?:)\/\//,
/**
* resolve relative url to absolute url
* @param url - relative url
* @returns - absolute url
*/
createAbsoluteUrl = function (url) {
var div = document.createElement("div"),
encode = function (url) {
return url.split("&").join("&").split("<").join("<").split('"').join(""");
};
if (reIsAbsolute.test(url)) {
return url;
}
div.innerHTML = '.'.supplant({url: encode(url)});
return div.firstChild.href;
},
/**
* creates an iframe and appends it to the container
*/
createIframe = function (container) {
var iframe = document.createElement('iframe');
iframe.frameBorder = iframe.border = '0';
iframe.scrolling = 'no';
iframe.src = "javascript:void(0)"; // jshint ignore:line
iframe.style.width = "100%";
//iframe.style.height = "200px";
container.innerHTML = "";
return container.appendChild(iframe);
},
createLighthouse = function(key, queue, container) {
window[key] = {
iframe: createIframe(container),
isIe: 1,
queue: queue,
onresize: function() {
frameResizer(window[key].iframe, window[key].isIe);
},
onrender: function() {
frameResizer(window[key].iframe, window[key].isIe);
}
};
},
/**
* render a mode
*/
createMode = function (message) {
var key;
if (validateMessages(message)) {
whenContainerReady(message.container, function(container) {
key = genGuid();
message.container = "tbl_widget_container";
message.publisher = message.publisher || publisher;
message.url = createAbsoluteUrl(message.url || getPageUrl());
message.referrer = message.referrer || getReferrer();
createLighthouse(key, createQueue(message), container);
writeIntoIframe(window[key].iframe, genIframeContent(key, message.publisher));
}, 500);
}
},
createQueue = function(message) {
var i,
p,
o,
result = [],
pageLevel = ["url", "referrer"],
mandatoryKey = getMandatoryKey(message);
if (mandatoryKey) {
pageLevel.push(mandatoryKey);
for (i = 0; p = pageLevel[i]; i++) { // jshint ignore:line
o = {};
o[p] = message[p];
result.push(o);
delete message[p];
}
result.push(message);
result.push({flush:true});
}
return result;
},
/**
* Finds an element inside the page part
* @param node - the head node
* @param tag - the tag to look foor
* @param attribute - element must contain this attribute
* @param content - optional, the attribute must have the content passed
* @returns the element we look for or null
*/
findElementByTagAndAttribute = function (node, tag, attribute, content) {
var list = node.getElementsByTagName(tag),
len = list.length,
i;
content = content || "";
for (i = 0; len > i; i++) {
if (list[i].getAttribute(attribute) && (!content || content === list[i].getAttribute(attribute).toLowerCase())) {
return list[i];
}
}
return void 0;
},
/**
* Finds an element inside the of the document
* tag - the requested tag (meta, script, link...)
* attribute - the tag must have this attribute
* content - optional, the tag attribute must have this content
* returns - the found element or null
*/
findHeadElement = function (tag, attribute, content) {
var i,
head = document.getElementsByTagName("head"),
len = head.length,
element;
if (head && head.length) {
for (i = 0; len > i; i++) {
element = findElementByTagAndAttribute(head[i], tag, attribute, content);
if (element) {
return element;
}
}
}
return void 0;
},
frameResizer = function(iframe, isIE) {
var iframeWin = iframe.contentWindow || iframe.contentDocument.parentWindow,
bodyHeight,
docHeight;
if (iframeWin.document.body) {
bodyHeight = iframeWin.document.body.scrollHeight;
docHeight = iframeWin.document.documentElement.scrollHeight;
iframe.style.height = (isIE ? (bodyHeight || docHeight ) + 10 : Math.min(docHeight, bodyHeight) + (bodyHeight === docHeight ? 0 : 10)) + "px";
if (isIE) {
iframe.style.height = (iframeWin.document.documentElement.scrollHeight || iframeWin.document.body.scrollHeight) ;
}
}
},
genGuid = function () {
return 'trc_lighthouse-' + Math.floor(Math.random() * MAX_INT).toString(36);
},
/**
* creates the content of the iframe
*/
genIframeContent = function(key, publisher) {
var scriptTag = {open: "<" + "script>", close: "<" + "/script>"},
text = [];
text.push("");
text.push("");
text.push("");
text.push(scriptTag.open);
text.push("if (/*@cc_on!@*/false) {");
text.push("document.documentElement.className='ie';");
text.push("}");
text.push(scriptTag.close);
text.push("");
text.push("");
text.push("");
if (document.domain !== document.location.hostname) {
text.push(scriptTag.open);
text.push("document.domain='" + document.domain + "';");
text.push(scriptTag.close);
}
text.push(scriptTag.open);
text.push("var _taboola = window.parent['" + key + "'].queue;" );
text.push("function afterRender(){window.parent['" + key + "'].onrender()}");
text.push("_taboola.push({onrender: afterRender})");
text.push(scriptTag.close);
text.push("<" + "script src='//cdn.taboola.com/libtrc/" + publisher + "/loader.js'>");
text.push(scriptTag.close);
text.push(scriptTag.open);
text.push("window.parent['" + key + "'].isIe = document.documentElement.className == 'ie';");
text.push("window.onresize = window.parent['" + key + "'].onresize;");
text.push(scriptTag.close);
text.push("");
return text.join("\n");
},
/**
* get the iframe container element
*/
getContainer = function (container) {
return container && (typeof container === "string" ? document.getElementById(container) : container);
},
/**
* get the currnet url
* @returns {String} clean version of current url
*/
getCurrentUrl = function () {
// split is used to remove the queryString and the hash part of the current url ?
return document.location.href; //.split("?")[0].split("#")[0];
},
getMandatoryKey = (function(pageLevelAttributes) {
return function(message) {
var i,
attr;
for (i = 0; attr = pageLevelAttributes[i]; i++) { // jshint ignore:line
if (attr in message) {
return attr;
}
}
};
}(["article", "video", "photo", "search", "category", "home"])),
/**
* returns page url
* if exists " + text);
}
},
/**
* handles _tbframe.push API
* @param msg
*/
pushMessage = function (msg) {
var i;
// clear previous calls
if (processTimer) {
clearTimeout(processTimer);
}
if (msg) {
if (isArray(msg)) {
for (i = 0; i < msg.length; i++) {
pushMessage(msg[i]);
pushMessage({flush: true});
}
return;
}
if ("publisher" in msg) {
publisher = msg.publisher;
}
if ("flush" in msg && msg.flush) {
createMode(queueToObject(currentQueue));
currentQueue = [];
return;
}
currentQueue.push(msg);
}
// scedual a process operation
// after QUEUE_PROCESS_INTERVAL ms of inactivity
processTimer = setTimeout(function() {
createMode(queueToObject(currentQueue));
currentQueue = [];
}, QUEUE_PROCESS_INTERVAL);
},
queueToObject = function(queue) {
var i,
message,
p,
result = {};
for (i = 0; message = queue[i]; i++) {
for (p in message) {
if (message.hasOwnProperty(p)) {
result[p] = message[p];
}
}
}
return result;
},
/**
* loop thru the queue at loading
*/
startQueue = function () {
var queue = window._tbframe = (window._tbframe || []);
queue.push = pushMessage;
while (queue.length) {
pushMessage(queue.shift());
}
},
/**
* validate that a message has all mandatory members
*/
validateMessages = (function () {
var mandatories = ["placement", "mode", "container", "publisher"];
return function (message) {
var i, p, mandatoryKey = getMandatoryKey(message);
if (!mandatoryKey || !message[mandatoryKey]) {
log("queue is missing a page level member such as video, article, photo, search, category or home.");
return false;
}
for (i = 0; p = mandatories[i]; i++) { // jshint ignore:line
if (!message[p]) {
log("queue is missing a mandatory member: " + p);
return false;
}
}
return true;
};
}()),
/**
* retry finding the container
*/
whenContainerReady = function(container, callback, tries) {
var element = getContainer(container);
if (element) {
return callback(element);
}
tries = tries || 0;
if (tries) {
setTimeout(function() {
whenContainerReady(container, callback, tries - 1);
}, 10);
} else {
log("Could not find container: '{container}'".supplant({container: container}));
}
},
// inject content into iframe
writeIntoIframe = function(iframe, text) {
var idoc = iframe.contentDocument || iframe.contentWindow.document;
idoc.write(text);
// remember to close 'idoc' to prevent loading animation from spinning for ever.
setTimeout(function(){
try {
idoc.close();
} catch (e) {
}
}, 0);
};
/**
* general purpose substite template
*
* 'helo {name}'.supplant({name: 'John Christiansen'}) --> hello John Christiansen
*/
String.prototype.supplant = function (o) {
return this.replace(/{([^{}]*)}/g, function (a, b) {
var r = o[b];
return typeof r !== 'undefined' ? r : a;
});
};
startQueue();
}());