<?php
/*
* This file is part of Psy Shell.
*
* (c) 2012-2020 Justin Hileman
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/
namespace Psy\Readline;
use Psy\Exception\BreakException;
/**
* An array-based Readline emulation implementation.
*/
class Transient implements Readline
{
private $history;
private $historySize;
private $eraseDups;
private $stdin;
/**
* Transient Readline is always supported.
*
* {@inheritdoc}
*/
public static function isSupported()
{
return true;
}
/**
* Transient Readline constructor.
*/
public function __construct($historyFile = null, $historySize = 0, $eraseDups = false)
{
// don't do anything with the history file...
$this->history = [];
$this->historySize = $historySize;
$this->eraseDups = $eraseDups;
}
/**
* {@inheritdoc}
*/
public function addHistory($line)
{
if ($this->eraseDups) {
if (($key = \array_search($line, $this->history)) !== false) {
unset($this->history[$key]);
}
}
$this->history[] = $line;
if ($this->historySize > 0) {
$histsize = \count($this->history);
if ($histsize > $this->historySize) {
$this->history = \array_slice($this->history, $histsize - $this->historySize);
}
}
$this->history = \array_values($this->history);
return true;
}
/**
* {@inheritdoc}
*/
public function clearHistory()
{
$this->history = [];
return true;
}
/**
* {@inheritdoc}
*/
public function listHistory()
{
return $this->history;
}
/**
* {@inheritdoc}
*/
public function readHistory()
{
return true;
}
/**
* {@inheritdoc}
*
* @throws BreakException if user hits Ctrl+D
*
* @return string
*/
public function readline($prompt = null)
{
echo $prompt;
return \rtrim(\fgets($this->getStdin()), "\n\r");
}
/**
* {@inheritdoc}
*/
public function redisplay()
{
// noop
}
/**
* {@inheritdoc}
*/
public function writeHistory()
{
return true;
}
/**
* Get a STDIN file handle.
*
* @throws BreakException if user hits Ctrl+D
*
* @return resource
*/
private function getStdin()
{
if (!isset($this->stdin)) {
$this->stdin = \fopen('php://stdin', 'r');
}
if (\feof($this->stdin)) {
throw new BreakException('Ctrl+D');
}
return $this->stdin;
}
}