https.php

<?php

if(!defined("IN_MYBB"))
{
	die("Direct initialization of this file is not allowed.<br /><br />Please make sure IN_MYBB is defined.");
}

$plugins->add_hook('pre_output_page', 'https_output_page');

function https_info() {
	return array(
		'name'			=> 'HTTPS Helper',
		'description'	=> 'Provides support for migrating to a HTTPS-enabled domain',
		'author'		=> 'Cameron:D',
		'version'		=> '0.1',
		/* Should still work with 1.8, but I haven't tested, I'm still on 1.6 */
		'compatibility'	=> '16*',
	);
}

function https_output_page($page) {
	// Some image hosts support HTTPS but users still post HTTP URLs, this will change those hosts
	// to use HTTPS, removing some (most, in my case) load from the image proxy
	$find = '~\<img src="http:\/\/(i\.imgur\.com|[a-z0-9]+\.deviantart\.net|\d+\.media\.tumblr\.com|[a-z0-9\.]+\.edgecastcdn\.net|derpicdn\.net|YOURBOARDURL\.com)~si';
	// Simply replaces the HTTP://... with //..... (Protocol-relative URL)
	// This could also be $replace = 'src="https://\\1'; to force HTTPS (When this code was writted I supported both HTTP and HTTPS)
	$replace = 'src="//\\1';
	$page = preg_replace($find, $replace, $page);

	//If the users is accessing over HTTPS...
	if(isset($_SERVER['HTTPS'])) {
		// Find every HTTP image
		$find = '~\<img src="(http:\/\/(.+?))"~si';
		$page = preg_replace_callback($find, function ($matches) {
			global $mybb;

			// Encode the image URL
			$encoded = bin2hex($matches[1]);
			// Sign the URL with the camo secret key (stops people abusing the proxy)
			// This requires you to add a new setting through your ACP named 'hmac_key'
			// And the key in your camo config needs to be the same
			$key = hash_hmac("sha1", $matches[1], $mybb->settings["hmac_key"]);
			// Get the original image filename, makes the URLs a bit more user-friendly
			// (i.e. if people save the image it has a sane name)
			$filename = substr(strrchr($matches[1], "/"), 1);
			// Build the new image URL
			$newurl = "https://YOURCAMOPROXYADDRESS/{$key}/{$encoded}/{$filename}";

			// And output it
			return "<img src=\"{$newurl}\"";
		}, $page);
	}

	// This section replace all links to your forum with the protocol-relative link
	$find = '~href\="https?:\/\/YOURBOARDURL\.com\~si';
	// Get rid of the 's?' above and make it https:// below to just force all old board links to be HTTPS
	$replace = 'href="//YOURBOARDURL.com';
	$page = preg_replace($find, $replace, $page);
	return $page;
}