private function _prefix_keyframe(css_group $keyframe, $apply_list)
{
$prefixes = array(3 => "@-ms-keyframes", 2 => "@-o-keyframes", 0 => "@-moz-keyframes", 1 => "@-webkit-keyframes");
foreach ($prefixes as $id => $value) {
if (isset($apply_list[$id]) && $apply_list[$id]) {
$new_name = str_replace('@keyframes', $prefixes[$id], $keyframe->name);
//Check if keyframe with prefix exists
$found = false;
foreach ($keyframe->siblings('css_group') as $sibling) {
if ($sibling->name == $new_name) {
$found = true;
}
}
if (!$found) {
//Create new keyframe only with prefix for the current vendor
$new_keyframe = $keyframe->make_clone();
$new_keyframe->name = $new_name;
$keyframe->insert_after($new_keyframe);
$this->_add_prefixes($new_keyframe, array($id => true), true, true);
}
}
}
}
/**
* Clean a CSS file
*
* @param css_group $css_doc CSS file to clean
*
* @return css_group
*/
public function clean(css_group $css_doc)
{
//Find tokens
$project_tokens = $this->_find_tokens();
//Clean selectors
$removed = 0;
$selector_usage = array();
foreach ($css_doc->find_all('css_group') as $group) {
/* @var $group css_group */
if (!$group->name || stripos($group->name, '@') !== false) {
continue;
//Ignore @media, @keyframes and future especial groups
}
$current_selectors = $group->selectors();
$valid_selectors = array();
foreach ($current_selectors as $selector) {
$include = true;
//Remove pseudo-class
$clean_selector = preg_replace('/\\:.*/', '', $selector);
//Look for selector tokens in the token list
foreach ($this->_get_tokens($clean_selector) as $token) {
if (!isset($project_tokens[$token])) {
//Remove current selector
$include = false;
}
}
if ($include) {
$valid_selectors[] = $selector;
if ($this->report_path) {
$count = 0;
foreach ($this->_get_tokens($clean_selector) as $token) {
$count += $project_tokens[$token];
}
$selector_usage[$clean_selector] = isset($selector_usage[$clean_selector]) ? $selector_usage[$clean_selector] + $count : $count;
}
}
}
//Set cleaned selectors, or remove entire group if empty
if (empty($valid_selectors)) {
$group->remove();
} else {
$group->selectors($valid_selectors);
}
if ($this->verbose) {
$dif = array_diff($current_selectors, $valid_selectors);
if (!empty($dif)) {
$removed += count($dif);
$dif = implode(', ', $dif);
echo "Removed {$dif}\n";
}
}
}
//Create report
if ($this->report_path) {
asort($selector_usage);
$lines = array('Selector usage report. Generated on ' . date('r'), '');
foreach ($selector_usage as $selector => $freq) {
$lines[] = "{$selector} found {$freq} references";
}
file_put_contents($this->report_path, implode(PHP_EOL, $lines));
}
if ($this->verbose) {
echo "\nClean done, removed {$removed} unused selectors\n";
}
return $css_doc;
}
/**
* @see http://net.tutsplus.com/tutorials/html-css-techniques/quick-tip-how-to-target-ie6-ie7-and-ie8-uniquely-with-4-characters/
*/
protected function _remove_ie_hacks(css_group $document)
{
foreach ($document->find_all('css_property') as $property) {
$is_hack = in_array($property->name, array('filter', '-ms-filter')) || in_array($property->name[0], array('*', '_')) || stripos($property->value, 'expression') === 0 || substr($property->value, -2) === '\\9';
//IE8 Hack
if ($is_hack) {
$property->remove();
}
}
}