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<?php
// This file is part of Moodle - http://moodle.org/
//
// Moodle is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// Moodle is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with Moodle. If not, see <http://www.gnu.org/licenses/>.
/**
* This file contains CSS related class, and function for the CSS optimiser.
*
* Please see the {@link css_optimiser} class for greater detail.
*
* NOTE: these functions are not expected to be used from any addons.
*
* @package core
* @subpackage cssoptimiser
* @copyright 2012 Sam Hemelryk
* @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
*/
defined('MOODLE_INTERNAL') || die();
if (!defined('THEME_DESIGNER_CACHE_LIFETIME')) {
// This can be also set in config.php file,
// it needs to be higher than the time it takes to generate all CSS content.
define('THEME_DESIGNER_CACHE_LIFETIME', 10);
}
/**
* Stores CSS in a file at the given path.
*
* This function either succeeds or throws an exception.
*
* @param theme_config $theme The theme that the CSS belongs to.
* @param string $csspath The path to store the CSS at.
* @param string $csscontent the complete CSS in one string
* @param bool $chunk If set to true these files will be chunked to ensure
* that no one file contains more than 4095 selectors.
* @param string $chunkurl If the CSS is be chunked then we need to know the URL
* to use for the chunked files.
*/
function css_store_css(theme_config $theme, $csspath, $csscontent, $chunk = false, $chunkurl = null) {
global $CFG;
clearstatcache();
if (!file_exists(dirname($csspath))) {
@mkdir(dirname($csspath), $CFG->directorypermissions, true);
}
// Prevent serving of incomplete file from concurrent request,
// the rename() should be more atomic than fwrite().
ignore_user_abort(true);
// First up write out the single file for all those using decent browsers.
css_write_file($csspath, $csscontent);
if ($chunk) {
// If we need to chunk the CSS for browsers that are sub-par.
$css = css_chunk_by_selector_count($csscontent, $chunkurl);
$files = count($css);
$count = 1;
foreach ($css as $content) {
if ($count === $files) {
// If there is more than one file and this IS the last file.
$filename = preg_replace('#\.css$#', '.0.css', $csspath);
} else {
// If there is more than one file and this is not the last file.
$filename = preg_replace('#\.css$#', '.'.$count.'.css', $csspath);
}
$count++;
css_write_file($filename, $content);
}
}
ignore_user_abort(false);
if (connection_aborted()) {
die;
}
}
/**
* Writes a CSS file.
*
* @param string $filename
* @param string $content
*/
function css_write_file($filename, $content) {
global $CFG;
if ($fp = fopen($filename.'.tmp', 'xb')) {
fwrite($fp, $content);
fclose($fp);
rename($filename.'.tmp', $filename);
@chmod($filename, $CFG->filepermissions);
@unlink($filename.'.tmp'); // Just in case anything fails.
}
}
/**
* Takes CSS and chunks it if the number of selectors within it exceeds $maxselectors.
*
* The chunking will not split a group of selectors, or a media query. That means that
* if n > $maxselectors and there are n selectors grouped together,
* they will not be chunked and you could end up with more selectors than desired.
* The same applies for a media query that has more than n selectors.
*
* Also, as we do not split group of selectors or media queries, the chunking might
* not be as optimal as it could be, having files with less selectors than it could
* potentially contain.
*
* String functions used here are not compliant with unicode characters. But that is
* not an issue as the syntax of CSS is using ASCII codes. Even if we have unicode
* characters in comments, or in the property 'content: ""', it will behave correcly.
*
* Please note that this strips out the comments if chunking happens.
*
* @param string $css The CSS to chunk.
* @param string $importurl The URL to use for import statements.
* @param int $maxselectors The number of selectors to limit a chunk to.
* @param int $buffer Not used any more.
* @return array An array of CSS chunks.
*/
function css_chunk_by_selector_count($css, $importurl, $maxselectors = 4095, $buffer = 50) {
// Check if we need to chunk this CSS file.
$count = substr_count($css, ',') + substr_count($css, '{');
if ($count < $maxselectors) {
// The number of selectors is less then the max - we're fine.
return array($css);
}
$chunks = array(); // The final chunks.
$offsets = array(); // The indexes to chunk at.
$offset = 0; // The current offset.
$selectorcount = 0; // The number of selectors since the last split.
$lastvalidoffset = 0; // The last valid index to split at.
$lastvalidoffsetselectorcount = 0; // The number of selectors used at the time were could split.
$inrule = 0; // The number of rules we are in, should not be greater than 1.
$inmedia = false; // Whether or not we are in a media query.
$mediacoming = false; // Whether or not we are expeting a media query.
$currentoffseterror = null; // Not null when we have recorded an error for the current split.
$offseterrors = array(); // The offsets where we found errors.
// Remove the comments. Because it's easier, safer and probably a lot of other good reasons.
$css = preg_replace('#/\*(.*?)\*/#s', '', $css);
$strlen = strlen($css);
// Walk through the CSS content character by character.
for ($i = 1; $i <= $strlen; $i++) {
$char = $css[$i - 1];
$offset = $i;
// Is that a media query that I see coming towards us?
if ($char === '@') {
if (!$inmedia && substr($css, $offset, 5) === 'media') {
$mediacoming = true;
}
}
// So we are entering a rule or a media query...
if ($char === '{') {
if ($mediacoming) {
$inmedia = true;
$mediacoming = false;
} else {
$inrule++;
$selectorcount++;
}
}
// Let's count the number of selectors, but only if we are not in a rule, or in
// the definition of a media query, as they can contain commas too.
if (!$mediacoming && !$inrule && $char === ',') {
$selectorcount++;
}
// We reached the end of something.
if ($char === '}') {
// Oh, we are in a media query.
if ($inmedia) {
if (!$inrule) {
// This is the end of the media query.
$inmedia = false;
} else {
// We were in a rule, in the media query.
$inrule--;
}
} else {
$inrule--;
// Handle stupid broken CSS where there are too many } brackets,
// as this can cause it to break (with chunking) where it would
// coincidentally have worked otherwise.
if ($inrule < 0) {
$inrule = 0;
}
}
// We are not in a media query, and there is no pending rule, it is safe to split here.
if (!$inmedia && !$inrule) {
$lastvalidoffset = $offset;
$lastvalidoffsetselectorcount = $selectorcount;
}
}
// Alright, this is splitting time...
if ($selectorcount > $maxselectors) {
if (!$lastvalidoffset) {
// We must have reached more selectors into one set than we were allowed. That means that either
// the chunk size value is too small, or that we have a gigantic group of selectors, or that a media
// query contains more selectors than the chunk size. We have to ignore this because we do not
// support split inside a group of selectors or media query.
if ($currentoffseterror === null) {
$currentoffseterror = $offset;
$offseterrors[] = $currentoffseterror;
}
} else {
// We identify the offset to split at and reset the number of selectors found from there.
$offsets[] = $lastvalidoffset;
$selectorcount = $selectorcount - $lastvalidoffsetselectorcount;
$lastvalidoffset = 0;
$currentoffseterror = null;
}
}
}
// Report offset errors.
if (!empty($offseterrors)) {
debugging('Could not find a safe place to split at offset(s): ' . implode(', ', $offseterrors) . '. Those were ignored.',
DEBUG_DEVELOPER);
}
// Now that we have got the offets, we can chunk the CSS.
$offsetcount = count($offsets);
foreach ($offsets as $key => $index) {
$start = 0;
if ($key > 0) {
$start = $offsets[$key - 1];
}
// From somewhere up to the offset.
$chunks[] = substr($css, $start, $index - $start);
}
// Add the last chunk (if there is one), from the last offset to the end of the string.
if (end($offsets) != $strlen) {
$chunks[] = substr($css, end($offsets));
}
// The array $chunks now contains CSS split into perfect sized chunks.
// Import statements can only appear at the very top of a CSS file.
// Imported sheets are applied in the the order they are imported and
// are followed by the contents of the CSS.
// This is terrible for performance.
// It means we must put the import statements at the top of the last chunk
// to ensure that things are always applied in the correct order.
// This way the chunked files are included in the order they were chunked
// followed by the contents of the final chunk in the actual sheet.
$importcss = '';
$slashargs = strpos($importurl, '.php?') === false;
$parts = count($chunks);
for ($i = 1; $i < $parts; $i++) {
if ($slashargs) {
$importcss .= "@import url({$importurl}/chunk{$i});\n";
} else {
$importcss .= "@import url({$importurl}&chunk={$i});\n";
}
}
$importcss .= end($chunks);
$chunks[key($chunks)] = $importcss;
return $chunks;
}
/**
* Sends a cached CSS file
*
* This function sends the cached CSS file. Remember it is generated on the first
* request, then optimised/minified, and finally cached for serving.
*
* @param string $csspath The path to the CSS file we want to serve.
* @param string $etag The revision to make sure we utilise any caches.
*/
function css_send_cached_css($csspath, $etag) {
// 60 days only - the revision may get incremented quite often.
$lifetime = 60*60*24*60;
header('Etag: "'.$etag.'"');
header('Content-Disposition: inline; filename="styles.php"');
header('Last-Modified: '. gmdate('D, d M Y H:i:s', filemtime($csspath)) .' GMT');
header('Expires: '. gmdate('D, d M Y H:i:s', time() + $lifetime) .' GMT');
header('Pragma: ');
header('Cache-Control: public, max-age='.$lifetime);
heade
10BC8
r('Accept-Ranges: none');
header('Content-Type: text/css; charset=utf-8');
if (!min_enable_zlib_compression()) {
header('Content-Length: '.filesize($csspath));
}
readfile($csspath);
die;
}
/**
* Sends a cached CSS content
*
* @param string $csscontent The actual CSS markup.
* @param string $etag The revision to make sure we utilise any caches.
*/
function css_send_cached_css_content($csscontent, $etag) {
// 60 days only - the revision may get incremented quite often.
$lifetime = 60*60*24*60;
header('Etag: "'.$etag.'"');
header('Content-Disposition: inline; filename="styles.php"');
header('Last-Modified: '. gmdate('D, d M Y H:i:s', time()) .' GMT');
header('Expires: '. gmdate('D, d M Y H:i:s', time() + $lifetime) .' GMT');
header('Pragma: ');
header('Cache-Control: public, max-age='.$lifetime);
header('Accept-Ranges: none');
header('Content-Type: text/css; charset=utf-8');
if (!min_enable_zlib_compression()) {
header('Content-Length: '.strlen($csscontent));
}
echo($csscontent);
die;
}
/**
* Sends CSS directly without caching it.
*
* This function takes a raw CSS string, optimises it if required, and then
* serves it.
* Turning both themedesignermode and CSS optimiser on at the same time is awful
* for performance because of the optimiser running here. However it was done so
* that theme designers could utilise the optimised output during development to
* help them optimise their CSS... not that they should write lazy CSS.
*
* @param string $css
*/
function css_send_uncached_css($css) {
header('Content-Disposition: inline; filename="styles_debug.php"');
header('Last-Modified: '. gmdate('D, d M Y H:i:s', time()) .' GMT');
header('Expires: '. gmdate('D, d M Y H:i:s', time() + THEME_DESIGNER_CACHE_LIFETIME) .' GMT');
header('Pragma: ');
header('Accept-Ranges: none');
header('Content-Type: text/css; charset=utf-8');
if (is_array($css)) {
$css = implode("\n\n", $css);
}
echo $css;
die;
}
/**
* Send file not modified headers
*
* @param int $lastmodified
* @param string $etag
*/
function css_send_unmodified($lastmodified, $etag) {
// 60 days only - the revision may get incremented quite often.
$lifetime = 60*60*24*60;
header('HTTP/1.1 304 Not Modified');
header('Expires: '. gmdate('D, d M Y H:i:s', time() + $lifetime) .' GMT');
header('Cache-Control: public, max-age='.$lifetime);
header('Content-Type: text/css; charset=utf-8');
header('Etag: "'.$etag.'"');
if ($lastmodified) {
header('Last-Modified: '. gmdate('D, d M Y H:i:s', $lastmodified) .' GMT');
}
die;
}
/**
* Sends a 404 message about CSS not being found.
*/
function css_send_css_not_found() {
header('HTTP/1.0 404 not found');
die('CSS was not found, sorry.');
}
/**
* Determines if the given value is a valid CSS colour.
*
* A CSS colour can be one of the following:
* - Hex colour: #AA66BB
* - RGB colour: rgb(0-255, 0-255, 0-255)
* - RGBA colour: rgba(0-255, 0-255, 0-255, 0-1)
* - HSL colour: hsl(0-360, 0-100%, 0-100%)
* - HSLA colour: hsla(0-360, 0-100%, 0-100%, 0-1)
*
* Or a recognised browser colour mapping {@link css_optimiser::$htmlcolours}
*
* @param string $value The colour value to check
* @return bool
*/
function css_is_colour($value) {
$value = trim($value);
$hex = '/^#([a-fA-F0-9]{1,3}|[a-fA-F0-9]{6})$/';
$rgb = '#^rgb\s*\(\s*(\d{1,3})\s*,\s*(\d{1,3})\s*,\s*(\d{1,3})\s*\)$#i';
$rgba = '#^rgba\s*\(\s*(\d{1,3})\s*,\s*(\d{1,3})\s*,\s*(\d{1,3})\s*,\s*(\d{1}(\.\d+)?)\s*\)$#i';
$hsl = '#^hsl\s*\(\s*(\d{1,3})\s*,\s*(\d{1,3})\%\s*,\s*(\d{1,3})\%\s*\)$#i';
$hsla = '#^hsla\s*\(\s*(\d{1,3})\s*,\s*(\d{1,3})\%\s*,\s*(\d{1,3})\%\s*,\s*(\d{1}(\.\d+)?)\s*\)$#i';
if (in_array(strtolower($value), array('inherit'))) {
return true;
} else if (preg_match($hex, $value)) {
return true;
} else if (in_array(strtolower($value), array_keys(css_optimiser::$htmlcolours))) {
return true;
} else if (preg_match($rgb, $value, $m) && $m[1] < 256 && $m[2] < 256 && $m[3] < 256) {
// It is an RGB colour.
return true;
} else if (preg_match($rgba, $value, $m) && $m[1] < 256 && $m[2] < 256 && $m[3] < 256) {
// It is an RGBA colour.
return true;
} else if (preg_match($hsl, $value, $m) && $m[1] <= 360 && $m[2] <= 100 && $m[3] <= 100) {
// It is an HSL colour.
return true;
} else if (preg_match($hsla, $value, $m) && $m[1] <= 360 && $m[2] <= 100 && $m[3] <= 100) {
// It is an HSLA colour.
return true;
}
// Doesn't look like a colour.
return false;
}
/**
* Returns true is the passed value looks like a CSS width.
* In order to pass this test the value must be purely numerical or end with a
* valid CSS unit term.
*
* @param string|int $value
* @return boolean
*/
function css_is_width($value) {
$value = trim($value);
if (in_array(strtolower($value), array('auto', 'inherit'))) {
return true;
}
if ((string)$value === '0' || preg_match('#^(\-\s*)?(\d*\.)?(\d+)\s*(em|px|pt|\%|in|cm|mm|ex|pc)$#i', $value)) {
return true;
}
return false;
}
/**
* A simple sorting function to sort two array values on the number of items they contain
*
* @param array $a
* @param array $b
* @return int
*/
function css_sort_by_count(array $a, array $b) {
$a = count($a);
$b = count($b);
if ($a == $b) {
return 0;
}
return ($a > $b) ? -1 : 1;
}
/**
* A basic CSS optimiser that strips out unwanted things and then processes CSS organising and cleaning styles.
*
* This CSS optimiser works by reading through a CSS string one character at a
* time and building an object structure of the CSS.
* As part of that processing styles are expanded out as much as they can be to
* ensure we collect all mappings, at the end of the processing those styles are
* then combined into an optimised form to keep them as short as possible.
*
* @package core
* @subpackage cssoptimiser
* @copyright 2012 Sam Hemelryk
* @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
*/
class css_optimiser {
/**
* Used when the processor is about to start processing.
* Processing states. Used internally.
*/
const PROCESSING_START = 0;
/**
* Used when the processor is currently processing a selector.
* Processing states. Used internally.
*/
const PROCESSING_SELECTORS = 0;
/**
* Used when the processor is currently processing a style.
* Processing states. Used internally.
*/
const PROCESSING_STYLES = 1;
/**
* Used when the processor is currently processing a comment.
* Processing states. Used internally.
*/
const PROCESSING_COMMENT = 2;
/**
* Used when the processor is currently processing an @ rule.
* Processing states. Used internally.
*/
const PROCESSING_ATRULE = 3;
/**
* The raw string length before optimisation.
* Stats variables set during and after processing
* @var int
*/
protected $rawstrlen = 0;
/**
* The number of comments that were removed during optimisation.
* Stats variables set during and after processing
* @var int
*/
protected $commentsincss = 0;
/**
* The number of rules in the CSS before optimisation.
* Stats variables set during and after processing
* @var int
*/
protected $rawrules = 0;
/**
* The number of selectors using in CSS rules before optimisation.
* Stats variables set during and after processing
* @var int
*/
protected $rawselectors = 0;
/**
* The string length after optimisation.
* Stats variables set during and after processing
* @var int
*/
protected $optimisedstrlen = 0;
/**
* The number of rules after optimisation.
* Stats variables set during and after processing
* @var int
*/
protected $optimisedrules = 0;
/**
* The number of selectors used in rules after optimisation.
* Stats variables set during and after processing
* @var int
*/
protected $optimisedselectors = 0;
10BC8
/**
* The start time of the optimisation.
* Stats variables set during and after processing
* @var int
*/
protected $timestart = 0;
/**
* The end time of the optimisation.
* Stats variables set during and after processing
* @var int
*/
protected $timecomplete = 0;
/**
* Will be set to any errors that may have occured during processing.
* This is updated only at the end of processing NOT during.
*
* @var array
*/
protected $errors = array();
/**
* Processes incoming CSS optimising it and then returning it.
*
* @param string $css The raw CSS to optimise
* @return string The optimised CSS
*/
public function process($css) {
// Easiest win there is.
$css = trim($css);
$this->reset_stats();
$this->timestart = microtime(true);
$this->rawstrlen = strlen($css);
// Don't try to process files with no content... it just doesn't make sense.
// But we should produce an error for them, an empty CSS file will lead to a
// useless request for those running theme designer mode.
if ($this->rawstrlen === 0) {
$this->errors[] = 'Skipping file as it has no content.';
return '';
}
// First up we need to remove all line breaks - this allows us to instantly
// reduce our processing requirements and as we will process everything
// into a new structure there's really nothing lost.
$css = preg_replace('#\r?\n#', ' ', $css);
// Next remove the comments... no need to them in an optimised world and
// knowing they're all gone allows us to REALLY make our processing simpler.
$css = preg_replace('#/\*(.*?)\*/#m', '', $css, -1, $this->commentsincss);
$medias = array(
'all' => new css_media()
);
$imports = array();
$charset = false;
// Keyframes are used for CSS animation they will be processed right at the very end.
$keyframes = array();
$currentprocess = self::PROCESSING_START;
$currentrule = css_rule::init();
$currentselector = css_selector::init();
$inquotes = false; // ' or "
$inbraces = false; // {
$inbrackets = false; // [
$inparenthesis = false; // (
/* @var css_media $currentmedia */
$currentmedia = $medias['all'];
$currentatrule = null;
$suspectatrule = false;
$buffer = '';
$char = null;
// Next we are going to iterate over every single character in $css.
// This is why we removed line breaks and comments!
for ($i = 0; $i < $this->rawstrlen; $i++) {
$lastchar = $char;
$char = substr($css, $i, 1);
if ($char == '@' && $buffer == '') {
$suspectatrule = true;
}
switch ($currentprocess) {
// Start processing an @ rule e.g. @media, @page, @keyframes.
case self::PROCESSING_ATRULE:
switch ($char) {
case ';':
if (!$inbraces) {
$buffer .= $char;
if ($currentatrule == 'import') {
$imports[] = $buffer;
$currentprocess = self::PROCESSING_SELECTORS;
} else if ($currentatrule == 'charset') {
$charset = $buffer;
$currentprocess = self::PROCESSING_SELECTORS;
}
}
if ($currentatrule !== 'media') {
$buffer = '';
$currentatrule = false;
}
// Continue 1: The switch processing chars
// Continue 2: The switch processing the state
// Continue 3: The for loop.
continue 3;
case '{':
$regexmediabasic = '#\s*@media\s*([a-zA-Z0-9]+(\s*,\s*[a-zA-Z0-9]+)*)\s*{#';
$regexadvmedia = '#\s*@media\s*([^{]+)#';
$regexkeyframes = '#@((\-moz\-|\-webkit\-|\-ms\-|\-o\-)?keyframes)\s*([^\s]+)#';
if ($currentatrule == 'media' && preg_match($regexmediabasic, $buffer, $matches)) {
// Basic media declaration.
$mediatypes = str_replace(' ', '', $matches[1]);
if (!array_key_exists($mediatypes, $medias)) {
$medias[$mediatypes] = new css_media($mediatypes);
}
$currentmedia = $medias[$mediatypes];
$currentprocess = self::PROCESSING_SELECTORS;
$buffer = '';
} else if ($currentatrule == 'media' && preg_match($regexadvmedia, $buffer, $matches)) {
// Advanced media query declaration http://www.w3.org/TR/css3-mediaqueries/.
$mediatypes = $matches[1];
$hash = md5($mediatypes);
$medias[$hash] = new css_media($mediatypes);
$currentmedia = $medias[$hash];
$currentprocess = self::PROCESSING_SELECTORS;
$buffer = '';
} else if ($currentatrule == 'keyframes' && preg_match($regexkeyframes, $buffer, $matches)) {
// Keyframes declaration, we treat it exactly like a @media declaration except we don't allow
// them to be overridden to ensure we don't mess anything up. (means we keep everything in order).
$keyframefor = $matches[1];
$keyframename = $matches[3];
$keyframe = new css_keyframe($keyframefor, $keyframename);
$keyframes[] = $keyframe;
$currentmedia = $keyframe;
$currentprocess = self::PROCESSING_SELECTORS;
$buffer = '';
}
// Continue 1: The switch processing chars
// Continue 2: The switch processing the state
// Continue 3: The for loop.
continue 3;
}
break;
// Start processing selectors.
case self::PROCESSING_START:
case self::PROCESSING_SELECTORS:
$regexatrule = '#@(media|import|charset|(\-moz\-|\-webkit\-|\-ms\-|\-o\-)?(keyframes))\s*#';
switch ($char) {
case '[':
$inbrackets ++;
$buffer .= $char;
// Continue 1: The switch processing chars
// Continue 2: The switch processing the state
// Continue 3: The for loop.
continue 3;
case ']':
$inbrackets --;
$buffer .= $char;
// Continue 1: The switch processing chars
// Continue 2: The switch processing the state
// Continue 3: The for loop.
continue 3;
case ' ':
if ($inbrackets) {
// Continue 1: The switch processing chars
// Continue 2: The switch processing the state
// Continue 3: The for loop.
continue 3;
}
if (!empty($buffer)) {
// Check for known @ rules.
if ($suspectatrule && preg_match($regexatrule, $buffer, $matches)) {
$currentatrule = (!empty($matches[3]))?$matches[3]:$matches[1];
$currentprocess = self::PROCESSING_ATRULE;
$buffer .= $char;
} else {
$currentselector->add($buffer);
$buffer = '';
}
}
$suspectatrule = false;
// Continue 1: The switch processing chars
// Continue 2: The switch processing the state
// Continue 3: The for loop.
continue 3;
case '{':
if ($inbrackets) {
// Continue 1: The switch processing chars
// Continue 2: The switch processing the state
// Continue 3: The for loop.
continue 3;
}
// Check for known @ rules.
if ($suspectatrule && preg_match($regexatrule, $buffer, $matches)) {
// Ahh we've been in an @rule, lets rewind one and have the @rule case process this.
$currentatrule = (!empty($matches[3]))?$matches[3]:$matches[1];
$currentprocess = self::PROCESSING_ATRULE;
$i--;
$suspectatrule = false;
// Continue 1: The switch processing chars
// Continue 2: The switch processing the state
// Continue 3: The for loop.
continue 3;
}
if ($buffer !== '') {
$currentselector->add($buffer);
}
$currentrule->add_selector($currentselector);
$currentselector = css_selector::init();
$currentprocess = self::PROCESSING_STYLES;
$buffer = '';
// Continue 1: The switch processing chars
// Continue 2: The switch processing the state
// Continue 3: The for loop.
continue 3;
case '}':
if ($inbrackets) {
// Continue 1: The switch processing chars
// Continue 2: The switch processing the state
// Continue 3: The for loop.
continue 3;
}
if ($currentatrule == 'media') {
$currentmedia = $medias['all'];
$currentatrule = false;
$buffer = '';
} else if (strpos($currentatrule, 'keyframes') !== false) {
$currentmedia = $medias['all'];
$currentatrule = false;
$buffer = '';
}
// Continue 1: The switch processing chars
// Continue 2: The switch processing the state
// Continue 3: The for loop.
continue 3;
case ',':
if ($inbrackets) {
// Continue 1: The switch processing chars
// Continue 2: The switch processing the state
// Continue 3: The for loop.
continue 3;
}
$currentselector->add($buffer);
$currentrule->add_selector($currentselector);
$currentselector = css_selector::init();
$buffer = '';
// Continue 1: The switch processing chars
// Continue 2: The switch processing the state
// Continue 3: The for loop.
continue 3;
}
break;
// Start processing styles.
case self::PROCESSING_STYLES:
if ($char == '"' || $char == "'") {
if ($inquotes === false) {
$inquotes = $char;
}
if ($inquotes === $char && $lastchar !== '\\') {
$inquotes = false;
}
}
if ($inquotes) {
$buffer .= $char;
continue 2;
}
switch ($char) {
case ';':
if ($inparenthesis) {
$buffer .= $char;
// Continue 1: The switch processing chars
// Continue 2: The switch processing the state
// Continue 3: The for loop.
continue 3;
}
$currentrule->add_style($buffer);
$buffer = '';
$inquotes = false;
// Continue 1: The switch processing chars
// Continue 2: The switch processing the state
// Continue 3: The for loop.
continue 3;
case '}':
$currentrule->add_style($buffer);
$this->rawselectors += $currentrule->get_selector_count();
$currentmedia->add_rule($currentrule);
$currentrule = css_rule::init();
$currentprocess = self::PROCESSING_SELECTORS;
$this->rawrules++;
$buffer = '';
$inquotes = false;
$inparenthesis = false;
// Continue 1: The switch processing chars
// Continue 2: The switch processing the state
// Continue 3: The for loop.
continue 3;
case '(':
$inparenthesis = true;
$buffer .= $char;
// Continue 1: The switch processing chars
// Continue 2: The switch processing the state
// Continue 3: The for loop.
continue 3;
case ')':
$inparenthesis = false;
$buffer .= $char;
// Continue 1: The switch processing chars
// Continue 2: The switch processing the state
// Continue 3: The for loop.
continue 3;
}
break;
}
$buffer .= $char;
}
foreach ($medias as $media) {
$this->optimise($media);
}
$css = $this->produce_css($charset, $imports, $medias, $keyframes);
$this->timecomplete = microtime(true);
return trim($css);
}
/**
* Produces CSS for the given charset, imports, media, and keyframes
* @param string $charset
* @param array $imports
* @param css_media[] $medias
* @param css_keyframe[] $keyframes
* @return string
*/
protected function produce_css($charset, array $imports, array $medias, array $keyframes) {
$css = '';
if (!empty($charset)) {
$imports[] = $charset;
}
if (!empty($imports)) {
$css .= implode("\n", $imports);
$css .= "\n\n";
}
$cssreset = array();
$cssstandard = array();
$csskeyframes = array();
// Process each media declaration individually.
foreach ($medias as $media) {
// If this declaration applies to all media types.
if (in_array('all', $media->get_types())) {
// Collect all rules that represet reset rules and remove them from the media object at the same time.
// We do this because we prioritise reset rules to the top of a CSS output. This ensures that they
// can't end up out of order because of optimisation.
$resetrules = $media->get_reset_rules(true);
if (!empty($resetrules)) {
$cssreset[] = css_writer::media('all', $resetrules);
}
}
// Get the standard cSS.
$cssstandard[] = $media->out();
}
// Finally if there are any keyframe declarations process them now.
if (count($keyframes) > 0) {
foreach ($keyframes as $keyframe) {
$this->optimisedrules += $keyframe->count_rules();
$this->optimisedselectors += $keyframe->count_selectors();
if ($keyframe->has_errors()) {
$this->errors += $keyframe->get_errors();
}
$csskeyframes[] = $keyframe->out();
}
}
// Join it all together.
$css .= join('', $cssreset);
$css .= join('', $cssstandard);
$css .= join('', $csskeyframes);
// Record the strlenght of the now optimised CSS.
$this->optimisedstrlen = strlen($css);
// Return the now produced CSS.
return $css;
}
/**
* Optimises the CSS rules within a rule collection of one form or another
*
* @param css_rule_collection $media
* @return void This function acts in reference
*/
protected function optimise(css_rule_collection $media) {
$media->organise_rules_by_selectors();
$this->optimisedrules += $media->count_rules();
$this->optimisedselectors += $media->count_selectors();
if ($media->has_errors()) {
$this->errors += $media->get_errors();
}
}
/**
* Returns an array of stats from the last processing run
* @return string
*/
public function get_stats() {
$stats = array(
'timestart' => $this->timestart,
'timecomplete' => $this->timecomplete,
'timetaken' => round($this->timecomplete - $this->timestart, 4),
'commentsincss' => $this->commentsincss,
'rawstrlen' => $this->rawstrlen,
'rawselectors' => $this->rawselectors,
'rawrules' => $this->rawrules,
'optimisedstrlen' => $this->optimisedstrlen,
'optimisedrules' => $this->optimisedrules,
'optimisedselectors' => $this->optimisedselectors,
'improvementstrlen' => '-',
'improvementrules' => '-',
'improvementselectors' => '-',
);
// Avoid division by 0 errors by checking we have valid raw values.
if ($this->rawstrlen > 0) {
$stats['improvementstrlen'] = round(100 - ($this->optimisedstrlen / $this->rawstrlen) * 100, 1).'%';
}
if ($this->rawrules > 0) {
$stats['improvementrules'] = round(100 - ($this->optimisedrules / $this->rawrules) * 100, 1).'%';