Css.php

<?php

class bdCache_Css
{
	public static function save($parameters, $css)
	{
		$css = utf8_trim($css);
		if (empty($css))
		{
			return false;
		}

		$filePath = self::getCssFilePath($parameters);
		$requestPaths = XenForo_Application::get('requestPaths');
		$requestBeforeBasePath = substr($requestPaths['fullBasePath'], 0, -1 * strlen($requestPaths['basePath']));

		if (!bdCache_File::existsAndNotEmpty($filePath))
		{
			$dirPath = dirname($filePath);
			XenForo_Helper_File::createDirectory($dirPath, true);

			// fix url('...')
			$offset = 0;
			$i = 0;
			while (true)
			{
				$strpos = strpos($css, 'url(', $offset);
				if ($strpos === false)
				{
					break;
					// while(true)
				}
				$offset = $strpos + 1;

				$insertOffset = 4;
				$firstChars = substr($css, $strpos + $insertOffset, 9);
				$veryFirstChar = substr($firstChars, 0, 1);
				if ($veryFirstChar === "'" OR $veryFirstChar === '"')
				{
					$firstChars = substr($firstChars, 1);
					$insertOffset++;
				}

				if (strpos($firstChars, 'http://') === 0)
				{
					// do nothing
				}
				elseif (strpos($firstChars, 'https://') === 0)
				{
					// do nothing
				}
				elseif (substr($firstChars, 0, 2) === '//')
				{
					// do nothing
				}
				elseif (substr($firstChars, 0, 1) === '/')
				{
					// append the host name
					$css = substr_replace($css, $requestBeforeBasePath, $strpos + $insertOffset, 0);
				}
				else
				{
					// adjust url to make it valid
					$css = substr_replace($css, $requestPaths['fullBasePath'], $strpos + $insertOffset, 0);
				}
			}

			$css .= call_user_func_array('sprintf', array(
				'/* CSS saved with [bd] Cache (%s) */',
				$requestPaths['fullUri'],
				$parameters,
			));

			file_put_contents($filePath, $css);
			XenForo_Helper_File::makeWritableByFtpUser($filePath);
		}
	}

	public static function redirect($parameters)
	{
		$filePath = self::getCssFilePath($parameters);

		if (bdCache_File::existsAndNotEmpty($filePath))
		{
			$url = XenForo_Link::convertUriToAbsoluteUri(self::getCssUrl($parameters), true);

			header('HTTP/1.1 301 Moved Permanently');
			header(sprintf('Location: %s', $url));
			exit();
		}
	}

	public static function replaceCssUrls(&$content)
	{
		if (!bdCache_Option::get('cssToFile'))
		{
			return true;
		}

		$offset = 0;
		$begin = '"css.php?';
		$beginLength = strlen($begin);
		$failed = 0;

		while (true)
		{
			$beginStrpos = strpos($content, $begin, $offset);
			if ($beginStrpos === false)
			{
				break;
				// while(true)
			}

			$endStrpos = strpos($content, '"', $beginStrpos + 1);
			if ($endStrpos === false)
			{
				break;
				// while(true)
			}
			//$endStrpos--;

			$parameters = substr($content, $beginStrpos + $beginLength, $endStrpos - $beginStrpos - $beginLength);
			$parameters = html_entity_decode($parameters);
			$offset = $beginStrpos + $beginLength;

			$filePath = self::getCssFilePath($parameters);
			if (bdCache_File::existsAndNotEmpty($filePath))
			{
				// start replacing...
				$oldUrlOffset = $beginStrpos + 1;
				$oldUrlLength = $endStrpos - $oldUrlOffset;
				$oldUrl = substr($content, $oldUrlOffset, $oldUrlLength);

				$newUrl = self::getCssUrl($parameters);
				$newUrlLength = strlen($newUrl);

				$content = substr_replace($content, $newUrl, $oldUrlOffset, $oldUrlLength);
			}
			else
			{
				$failed++;
			}
		}

		return ($failed == 0);
	}

	public static function doHouseKeeping()
	{
		$cssPath = sprintf('%s/bdCache/css', XenForo_Helper_File::getExternalDataPath());

		$dirs = glob(sprintf('%s/*', $cssPath));
		$cssDirs = array();

		foreach ($dirs as $dir)
		{
			$dirName = basename($dir);

			if (is_numeric($dirName))
			{
				$cssDirs[intval($dirName)] = $dir;
			}
		}
		ksort($cssDirs);

		if (empty($cssDirs))
		{
			// nothing?
			// maybe CSS caching is disabled
			return false;
		}

		// leave out the latest directory, it contains current files
		array_pop($cssDirs);

		foreach ($cssDirs as $dir)
		{
			bdCache_File::removeDirectory($dir);
		}

		return true;
	}

	public static function getCssFilePath($parameters)
	{
		list($modifiedDate, $hash) = self::_getModifiedDateAndHash($parameters);

		return sprintf('%s/bdCache/css/%d/%s.css', XenForo_Helper_File::getExternalDataPath(), $modifiedDate, $hash);
	}

	public static function getCssUrl($parameters)
	{
		list($modifiedDate, $hash) = self::_getModifiedDateAndHash($parameters);

		$url = sprintf('%s/bdCache/css/%d/%s.css', XenForo_Application::$externalDataUrl, $modifiedDate, $hash);

		return $url;
	}

	protected static function _getModifiedDateAndHash($parameters)
	{
		parse_str($parameters, $parsed);
		ksort($parsed);

		$modifiedDate = (isset($parsed['d']) ? $parsed['d'] : 0);
		$hash = md5(implode('', $parsed));

		return array(
			$modifiedDate,
			$hash
		);
	}

}