Chris@0: <?php
Chris@0: 
Chris@0: /*
Chris@0:  * This file is part of Psy Shell.
Chris@0:  *
Chris@0:  * (c) 2012-2017 Justin Hileman
Chris@0:  *
Chris@0:  * For the full copyright and license information, please view the LICENSE
Chris@0:  * file that was distributed with this source code.
Chris@0:  */
Chris@0: 
Chris@0: namespace Psy\Readline;
Chris@0: 
Chris@0: use Psy\Util\Str;
Chris@0: 
Chris@0: /**
Chris@0:  * A Libedit-based Readline implementation.
Chris@0:  *
Chris@0:  * This is largely the same as the Readline implementation, but it emulates
Chris@0:  * support for `readline_list_history` since PHP decided it was a good idea to
Chris@0:  * ship a fake Readline implementation that is missing history support.
Chris@0:  */
Chris@0: class Libedit extends GNUReadline
Chris@0: {
Chris@0:     /**
Chris@0:      * Let's emulate GNU Readline by manually reading and parsing the history file!
Chris@0:      *
Chris@0:      * @return bool
Chris@0:      */
Chris@0:     public static function isSupported()
Chris@0:     {
Chris@0:         return function_exists('readline') && !function_exists('readline_list_history');
Chris@0:     }
Chris@0: 
Chris@0:     /**
Chris@0:      * {@inheritdoc}
Chris@0:      */
Chris@0:     public function listHistory()
Chris@0:     {
Chris@0:         $history = file_get_contents($this->historyFile);
Chris@0:         if (!$history) {
Chris@0:             return array();
Chris@0:         }
Chris@0: 
Chris@0:         // libedit doesn't seem to support non-unix line separators.
Chris@0:         $history = explode("\n", $history);
Chris@0: 
Chris@0:         // shift the history signature, ensure it's valid
Chris@0:         if (array_shift($history) !== '_HiStOrY_V2_') {
Chris@0:             return array();
Chris@0:         }
Chris@0: 
Chris@0:         // decode the line
Chris@0:         $history = array_map(array($this, 'parseHistoryLine'), $history);
Chris@0:         // filter empty lines & comments
Chris@0:         return array_values(array_filter($history));
Chris@0:     }
Chris@0: 
Chris@0:     /**
Chris@0:      * From GNUReadline (readline/histfile.c & readline/histexpand.c):
Chris@0:      * lines starting with "\0" are comments or timestamps;
Chris@0:      * if "\0" is found in an entry,
Chris@0:      * everything from it until the next line is a comment.
Chris@0:      *
Chris@0:      * @param string $line The history line to parse
Chris@0:      *
Chris@0:      * @return string | null
Chris@0:      */
Chris@0:     protected function parseHistoryLine($line)
Chris@0:     {
Chris@0:         // empty line, comment or timestamp
Chris@0:         if (!$line || $line[0] === "\0") {
Chris@0:             return;
Chris@0:         }
Chris@0:         // if "\0" is found in an entry, then
Chris@0:         // everything from it until the end of line is a comment.
Chris@0:         if (($pos = strpos($line, "\0")) !== false) {
Chris@0:             $line = substr($line, 0, $pos);
Chris@0:         }
Chris@0: 
Chris@0:         return ($line !== '') ? Str::unvis($line) : null;
Chris@0:     }
Chris@0: }