persistance_context = $this->_registry->get(
'cache.strategy.persistence-context',
self::KEY_FOR_PERSISTANCE,
AI1EC_CACHE_PATH
);
$this->lessphp_controller = $this->_registry->get( 'less.lessphp' );
$this->db_adapter = $this->_registry->get( 'model.option' );
$this->preview_mode = $preview_mode;
}
/**
* Renders the css for our frontend.
*
* Sets etags to avoid sending not needed data
*/
public function render_css() {
header( 'HTTP/1.1 200 OK' );
header( 'Content-Type: text/css', true, 200 );
// Aggressive caching to save future requests from the same client.
$etag = '"' . md5( __FILE__ . $_GET[self::QUERY_STRING_PARAM] ) . '"';
header( 'ETag: ' . $etag );
$max_age = 31536000;
$time_sys = $this->_registry->get( 'date.system' );
header(
'Expires: ' .
gmdate(
'D, d M Y H:i:s',
$time_sys->current_time() + $max_age
) .
' GMT'
);
header( 'Cache-Control: public, max-age=' . $max_age );
if (
empty( $_SERVER['HTTP_IF_NONE_MATCH'] ) ||
$etag !== stripslashes( $_SERVER['HTTP_IF_NONE_MATCH'] )
) {
// compress data if possible
$compatibility_ob = $this->_registry->get( 'compatibility.ob' );
if ( $this->_registry->get( 'http.request' )->client_use_gzip() ) {
$compatibility_ob->start( 'ob_gzhandler' );
header( 'Content-Encoding: gzip' );
} else {
$compatibility_ob->start();
}
$content = $this->get_compiled_css();
echo $content;
$compatibility_ob->end_flush();
} else {
// Not modified!
status_header( 304 );
}
// We're done!
Ai1ec_Http_Response_Helper::stop( 0 );
}
/**
*
* @param string $css
* @throws Ai1ec_Cache_Write_Exception
*/
public function update_persistence_layer( $css ) {
$this->persistance_context->write_data_to_persistence( $css );
$this->save_less_parse_time();
}
/**
* Get the url to retrieve the css
*
* @return string
*/
public function get_css_url() {
$time = $this->db_adapter->get( self::QUERY_STRING_PARAM );
$template_helper = $this->_registry->get( 'template.link.helper' );
return $template_helper->get_site_url() . "/?" . self::QUERY_STRING_PARAM .
"=$time";
}
/**
* Create the link that will be added to the frontend
*/
public function add_link_to_html_for_frontend() {
$preview = '';
if( true === $this->preview_mode ) {
// bypass browser caching of the css
$now = strtotime( 'now' );
$preview = "&preview=1&nocache={$now}&ai1ec_stylesheet=" . $_GET['ai1ec_stylesheet'];
}
$url = $this->get_css_url() . $preview;
wp_enqueue_style( 'ai1ec_style', $url );
}
/**
* Invalidate the persistence layer only after a successful compile of the
* LESS files.
*
* @param array $variables LESS variable array to use
* @param boolean $update_persistence Whether the persist successful compile
*
* @return boolean Whether successful
*/
public function invalidate_cache(
array $variables = null,
$update_persistence = false
) {
// Reset the parse time to force a browser reload of the CSS, whether we are
// updating persistence or not.
$this->save_less_parse_time();
$notification = $this->_registry->get( 'notification.admin' );
try {
// Try to parse the css
$css = $this->lessphp_controller->parse_less_files( $variables );
if ( $update_persistence ) {
$this->update_persistence_layer( $css );
} else {
$this->persistance_context->delete_data_from_persistence();
}
} catch ( Ai1ec_Cache_Write_Exception $e ) {
// This means successful during parsing but problems persisting the CSS.
$message = '' . Ai1ec_I18n::__( "The LESS file compiled correctly but there was an error while saving the generated CSS to persistence." ) . '
';
$notification->store( $message, 'error' );
return false;
} catch ( Exception $e ) {
// An error from lessphp.
$message = sprintf(
Ai1ec_I18n::__( 'There was an error while compiling CSS. The message returned was: %s
' ),
$e->getMessage()
);
$notification->store( $message, 'error', 1 );
return false;
}
return true;
}
/**
* Update the less variables on the DB and recompile the CSS
*
* @param array $variables
* @param boolean $resetting are we resetting or updating variables?
*/
public function update_variables_and_compile_css( array $variables, $resetting ) {
$no_parse_errors = $this->invalidate_cache( $variables, true );
$notification = $this->_registry->get( 'notification.admin' );
if ( $no_parse_errors ) {
$this->db_adapter->set(
Ai1ec_Less_Lessphp::DB_KEY_FOR_LESS_VARIABLES,
$variables
);
if ( true === $resetting ) {
$message = sprintf(
'' . Ai1ec_I18n::__(
"Theme options were successfully reset to their default values. Visit site"
) . '
',
get_site_url()
);
} else {
$message = sprintf(
'' .Ai1ec_I18n::__(
"Theme options were updated successfully. Visit site"
) . '
',
get_site_url()
);
}
$notification->store( $message );
}
}
/**
* Try to get the CSS from cache.
* If it's not there re-generate it and save it to cache
* If we are in preview mode, recompile the css using the theme present in the url.
*
*/
private function get_compiled_css() {
try {
// If we want to force a recompile, we throw an exception.
if( $this->preview_mode === true || self::PARSE_LESS_FILES_AT_EVERY_REQUEST === true ) {
throw new Ai1ec_Cache_Not_Set_Exception();
}else {
// This throws an exception if the key is not set
$css = $this->persistance_context->get_data_from_persistence();
return $css;
}
} catch ( Ai1ec_Cache_Not_Set_Exception $e ) {
// If we are in preview mode we force a recompile and we pass the variables.
if( $this->preview_mode ) {
return $this->lessphp_controller->parse_less_files(
$this->lessphp_controller->get_less_variable_data_from_config_file()
);
} else {
$css = $this->lessphp_controller->parse_less_files();
}
try {
$this->update_persistence_layer( $css );
return $css;
} catch ( Ai1ec_Cache_Write_Exception $e ) {
// If something is really broken, still return the css.
// This means we parse it every time. This should never happen.
return $css;
}
}
}
/**
* Save the compile time to the db so that we can use it to build the link
*/
private function save_less_parse_time() {
$this->db_adapter->set(
self::QUERY_STRING_PARAM,
$this->_registry->get( 'date.system' )->current_time()
);
}
}