Chris@13: <?php
Chris@13: 
Chris@13: /*
Chris@13:  * This file is part of Psy Shell.
Chris@13:  *
Chris@13:  * (c) 2012-2018 Justin Hileman
Chris@13:  *
Chris@13:  * For the full copyright and license information, please view the LICENSE
Chris@13:  * file that was distributed with this source code.
Chris@13:  */
Chris@13: 
Chris@13: namespace Psy\Readline;
Chris@13: 
Chris@13: use Psy\Util\Str;
Chris@13: 
Chris@13: /**
Chris@13:  * A Libedit-based Readline implementation.
Chris@13:  *
Chris@13:  * This is largely the same as the Readline implementation, but it emulates
Chris@13:  * support for `readline_list_history` since PHP decided it was a good idea to
Chris@13:  * ship a fake Readline implementation that is missing history support.
Chris@13:  */
Chris@13: class Libedit extends GNUReadline
Chris@13: {
Chris@13:     /**
Chris@13:      * Let's emulate GNU Readline by manually reading and parsing the history file!
Chris@13:      *
Chris@13:      * @return bool
Chris@13:      */
Chris@13:     public static function isSupported()
Chris@13:     {
Chris@17:         return \function_exists('readline') && !\function_exists('readline_list_history');
Chris@13:     }
Chris@13: 
Chris@13:     /**
Chris@13:      * {@inheritdoc}
Chris@13:      */
Chris@13:     public function listHistory()
Chris@13:     {
Chris@17:         $history = \file_get_contents($this->historyFile);
Chris@13:         if (!$history) {
Chris@13:             return [];
Chris@13:         }
Chris@13: 
Chris@13:         // libedit doesn't seem to support non-unix line separators.
Chris@17:         $history = \explode("\n", $history);
Chris@13: 
Chris@13:         // shift the history signature, ensure it's valid
Chris@17:         if (\array_shift($history) !== '_HiStOrY_V2_') {
Chris@13:             return [];
Chris@13:         }
Chris@13: 
Chris@13:         // decode the line
Chris@17:         $history = \array_map([$this, 'parseHistoryLine'], $history);
Chris@13:         // filter empty lines & comments
Chris@17:         return \array_values(\array_filter($history));
Chris@13:     }
Chris@13: 
Chris@13:     /**
Chris@13:      * From GNUReadline (readline/histfile.c & readline/histexpand.c):
Chris@13:      * lines starting with "\0" are comments or timestamps;
Chris@13:      * if "\0" is found in an entry,
Chris@13:      * everything from it until the next line is a comment.
Chris@13:      *
Chris@13:      * @param string $line The history line to parse
Chris@13:      *
Chris@13:      * @return string | null
Chris@13:      */
Chris@13:     protected function parseHistoryLine($line)
Chris@13:     {
Chris@13:         // empty line, comment or timestamp
Chris@13:         if (!$line || $line[0] === "\0") {
Chris@13:             return;
Chris@13:         }
Chris@13:         // if "\0" is found in an entry, then
Chris@13:         // everything from it until the end of line is a comment.
Chris@17:         if (($pos = \strpos($line, "\0")) !== false) {
Chris@17:             $line = \substr($line, 0, $pos);
Chris@13:         }
Chris@13: 
Chris@13:         return ($line !== '') ? Str::unvis($line) : null;
Chris@13:     }
Chris@13: }