/**
* WordPress inline HTML embed
*
* @since 4.4.0
* @output wp-includes/js/wp-embed.js
*
* Single line comments should not be used since they will break
* the script when inlined in get_post_embed_html(), specifically
* when the comments are not stripped out due to SCRIPT_DEBUG
* being turned on.
*/
(function ( window, document ) {
'use strict';

/* Abort for ancient browsers. */
if ( ! document.querySelector || ! window.addEventListener || typeof URL === 'undefined' ) {
return;
}

/** @namespace wp */
window.wp = window.wp || {};

/* Abort if script was already executed. */
if ( !! window.wp.receiveEmbedMessage ) {
return;
}

/**
* Receive embed message.
*
* @param {MessageEvent} e
*/
window.wp.receiveEmbedMessage = function( e ) {
var data = e.data;

/* Verify shape of message. */
if (
! ( data || data.secret || data.message || data.value ) ||
/[^a-zA-Z0-9]/.test( data.secret )
) {
return;
}

var iframes = document.querySelectorAll( 'iframe[data-secret="' + data.secret + '"]' ),
blockquotes = document.querySelectorAll( 'blockquote[data-secret="' + data.secret + '"]' ),
allowedProtocols = new RegExp( '^https?:$', 'i' ),
i, source, height, sourceURL, targetURL;

for ( i = 0; i < blockquotes.length; i++ ) {
blockquotes[ i ].style.display = 'none';
}

for ( i = 0; i < iframes.length; i++ ) {
source = iframes[ i ];

if ( e.source !== source.contentWindow ) {
continue;
}

source.removeAttribute( 'style' );

if ( 'height' === data.message ) {
/* Resize the iframe on request. */
height = parseInt( data.value, 10 );
if ( height > 1000 ) {
height = 1000;
} else if ( ~~height < 200 ) {
height = 200;
}

source.height = height;
} else if ( 'link' === data.message ) {
/* Link to a specific URL on request. */
sourceURL = new URL( source.getAttribute( 'src' ) );
targetURL = new URL( data.value );

if (
allowedProtocols.test( targetURL.protocol ) &&
targetURL.host === sourceURL.host &&
document.activeElement === source
) {
window.top.location.href = data.value;
}
}
}
};

function onLoad() {
var iframes = document.querySelectorAll( 'iframe.wp-embedded-content' ),
i, source, secret;

for ( i = 0; i < iframes.length; i++ ) {
/** @var {IframeElement} */
source = iframes[ i ];

secret = source.getAttribute( 'data-secret' );
if ( ! secret ) {
/* Add secret to iframe */
secret = Math.random().toString( 36 ).substring( 2, 12 );
source.src += '#?secret=' + secret;
source.setAttribute( 'data-secret', secret );
}

/*
* Let post embed window know that the parent is ready for receiving the height message, in case the iframe
* loaded before wp-embed.js was loaded. When the ready message is received by the post embed window, the
* window will then (re-)send the height message right away.
*/
source.contentWindow.postMessage( {
message: 'ready',
secret: secret
}, '*' );
}
}

window.addEventListener( 'message', window.wp.receiveEmbedMessage, false );
document.addEventListener( 'DOMContentLoaded', onLoad, false );
})( window, document );