<?php

if ( ! defined( 'ABSPATH' ) ) {

	die( 'These aren\'t the droids you\'re looking for.' );
}

if ( ! class_exists( 'SuextMinifyCssCompressor' ) ) {

	/**
	 * Compress CSS
	 *
	 * This is a heavy regex-based removal of whitespace, unnecessary
	 * comments and tokens, and some CSS value minimization, where practical.
	 * Many steps have been taken to avoid breaking comment-based hacks,
	 * including the ie5/mac filter (and its inversion), but expect tricky
	 * hacks involving comment tokens in 'content' value strings to break
	 * minimization badly. A test suite is available.
	 *
	 * @package Minify
	 * @author Stephen Clay <steve@mrclay.org>
	 * @author http://code.google.com/u/1stvamp/ (Issue 64 patch)
	 */
	class SuextMinifyCssCompressor {

		/**
		 * Minify a CSS string
		 *
		 * @param string $css
		 *
		 * @param array $options (currently ignored)
		 *
		 * @return string
		 */
		public static function process( $css, $options = array() ) {

			$instance = new SuextMinifyCssCompressor( $options );

			return $instance->_process( $css );
		}

		/**
		 * @var array
		 */
		protected $_options = null;

		/**
		 * Are we "in" a hack? I.e. are some browsers targetted until the next comment?
		 *
		 * @var bool
		 */
		protected $_inHack = false;


		/**
		 * Constructor
		 *
		 * @param array $options (currently ignored)
		 */
		private function __construct($options)
		{
			$this->_options = $options;
		}

		/**
		 * Minify a CSS string
		 *
		 * @param string $css
		 *
		 * @return string
		 */
		protected function _process($css)
		{
			$css = str_replace("\r\n", "\n", $css);

			// preserve empty comment after '>'
			// http://www.webdevout.net/css-hacks#in_css-selectors
			$css = preg_replace('@>/\\*\\s*\\*/@', '>/*keep*/', $css);

			// preserve empty comment between property and value
			// http://css-discuss.incutio.com/?page=BoxModelHack
			$css = preg_replace('@/\\*\\s*\\*/\\s*:@', '/*keep*/:', $css);
			$css = preg_replace('@:\\s*/\\*\\s*\\*/@', ':/*keep*/', $css);

			// apply callback to all valid comments (and strip out surrounding ws
			$css = preg_replace_callback('@\\s*/\\*([\\s\\S]*?)\\*/\\s*@'
				,array($this, '_commentCB'), $css);

			// remove ws around { } and last semicolon in declaration block
			$css = preg_replace('/\\s*{\\s*/', '{', $css);
			$css = preg_replace('/;?\\s*}\\s*/', '}', $css);

			// remove ws surrounding semicolons
			$css = preg_replace('/\\s*;\\s*/', ';', $css);

			// remove ws around urls
			$css = preg_replace('/
					url\\(      # url(
					\\s*
					([^\\)]+?)  # 1 = the URL (really just a bunch of non right parenthesis)
					\\s*
					\\)         # )
				/x', 'url($1)', $css);

			// remove ws between rules and colons
			$css = preg_replace('/
					\\s*
					([{;])              # 1 = beginning of block or rule separator
					\\s*
					([\\*_]?[\\w\\-]+)  # 2 = property (and maybe IE filter)
					\\s*
					:
					\\s*
					(\\b|[#\'"-])        # 3 = first character of a value
				/x', '$1$2:$3', $css);

			// remove ws in selectors
			$css = preg_replace_callback('/
					(?:              # non-capture
					\\s*
					[^~>+,\\s]+  # selector part
					\\s*
					[,>+~]       # combinators
					)+
					\\s*
					[^~>+,\\s]+      # selector part
					{                # open declaration block
				/x'
				,array($this, '_selectorsCB'), $css);

			// minimize hex colors
			$css = preg_replace('/([^=])#([a-f\\d])\\2([a-f\\d])\\3([a-f\\d])\\4([\\s;\\}])/i'
				, '$1#$2$3$4$5', $css);

			// remove spaces between font families
			$css = preg_replace_callback('/font-family:([^;}]+)([;}])/'
				,array($this, '_fontFamilyCB'), $css);

			$css = preg_replace('/@import\\s+url/', '@import url', $css);

			// replace any ws involving newlines with a single newline
			$css = preg_replace('/[ \\t]*\\n+\\s*/', "\n", $css);

			// separate common descendent selectors w/ newlines (to limit line lengths)
			$css = preg_replace('/([\\w#\\.\\*]+)\\s+([\\w#\\.\\*]+){/', "$1\n$2{", $css);

			// Use newline after 1st numeric value (to limit line lengths).
			$css = preg_replace('/
				((?:padding|margin|border|outline):\\d+(?:px|em)?) # 1 = prop : 1st numeric value
				\\s+
				/x'
				,"$1\n", $css);

			// prevent triggering IE6 bug: http://www.crankygeek.com/ie6pebug/
			$css = preg_replace('/:first-l(etter|ine)\\{/', ':first-l$1 {', $css);

			return trim($css);
		}

		/**
		 * Replace what looks like a set of selectors
		 *
		 * @param array $m regex matches
		 *
		 * @return string
		 */
		protected function _selectorsCB($m)
		{
			// remove ws around the combinators
			return preg_replace('/\\s*([,>+~])\\s*/', '$1', $m[0]);
		}

		/**
		 * Process a comment and return a replacement
		 *
		 * @param array $m regex matches
		 *
		 * @return string
		 */
		protected function _commentCB($m)
		{
			$hasSurroundingWs = (trim($m[0]) !== $m[1]);
			$m = $m[1];
			// $m is the comment content w/o the surrounding tokens,
			// but the return value will replace the entire comment.
			if ($m === 'keep') {
				return '/**/';
			}
			if ($m === '" "') {
				// component of http://tantek.com/CSS/Examples/midpass.html
				return '/*" "*/';
			}
			if (preg_match('@";\\}\\s*\\}/\\*\\s+@', $m)) {
				// component of http://tantek.com/CSS/Examples/midpass.html
				return '/*";}}/* */';
			}
			if ($this->_inHack) {
				// inversion: feeding only to one browser
				if (preg_match('@
						^/               # comment started like /*/
						\\s*
						(\\S[\\s\\S]+?)  # has at least some non-ws content
						\\s*
						/\\*             # ends like /*/ or /**/
					@x', $m, $n)) {
					// end hack mode after this comment, but preserve the hack and comment content
					$this->_inHack = false;
					return "/*/{$n[1]}/**/";
				}
			}
			if (substr($m, -1) === '\\') { // comment ends like \*/
				// begin hack mode and preserve hack
				$this->_inHack = true;
				return '/*\\*/';
			}
			if ($m !== '' && $m[0] === '/') { // comment looks like /*/ foo */
				// begin hack mode and preserve hack
				$this->_inHack = true;
				return '/*/*/';
			}
			if ($this->_inHack) {
				// a regular comment ends hack mode but should be preserved
				$this->_inHack = false;
				return '/**/';
			}
			// Issue 107: if there's any surrounding whitespace, it may be important, so
			// replace the comment with a single space
			return $hasSurroundingWs // remove all other comments
				? ' '
				: '';
		}

		/**
		 * Process a font-family listing and return a replacement
		 *
		 * @param array $m regex matches
		 *
		 * @return string
		 */
		protected function _fontFamilyCB($m)
		{
			/*
			 * Update on 2023/11/07 by jsmoriss: Changed null to $limit = -1.
			 */
			$pieces = preg_split( '/(\'[^\']+\'|"[^"]+")/', $m[ 1 ], $limit = -1, PREG_SPLIT_DELIM_CAPTURE | PREG_SPLIT_NO_EMPTY );

			$out = 'font-family:';

			while (null !== ($piece = array_shift($pieces))) {

				if ($piece[0] !== '"' && $piece[0] !== "'") {

					$piece = preg_replace('/\\s+/', ' ', $piece);

					$piece = preg_replace('/\\s?,\\s?/', ',', $piece);
				}

				$out .= $piece;
			}

			return $out . $m[2];
		}
	}
}