<?php declare(strict_types=1);
/**
* @package s9e\TextFormatter
* @copyright Copyright (c) 2010-2021 The s9e authors
* @license http://www.opensource.org/licenses/mit-license.php The MIT License
*/
namespace s9e\TextFormatter\Configurator;
use RuntimeException;
use s9e\TextFormatter\Configurator\RecursiveParser\MatcherInterface;
class RecursiveParser
{
/**
* @var array Callback associated with each match name
*/
protected $callbacks = [];
/**
* @var array Match names associated with each group
*/
protected $groupMatches = [];
/**
* @var array Groups associated with each match name
*/
protected $matchGroups = [];
/**
* @var string Regexp used to match input
*/
protected $regexp;
/**
* Parse given string
*
* @param string $str
* @param string $name Allowed match, either match name or group name (default: allow all)
* @return mixed
*/
public function parse(string $str, string $name = '')
{
$regexp = $this->regexp;
if ($name !== '')
{
$restrict = (isset($this->groupMatches[$name])) ? implode('|', $this->groupMatches[$name]) : $name;
$regexp = preg_replace('(\\(\\?<(?!(?:' . $restrict . '|\\w+\\d+)>))', '(*F)$0', $regexp);
}
preg_match($regexp, $str, $m);
if (!isset($m['MARK']))
{
throw new RuntimeException('Cannot parse ' . var_export($str, true));
}
$name = $m['MARK'];
$args = $this->getArguments($m, $name);
return [
'groups' => $this->matchGroups[$name] ?? [],
'match' => $name,
'value' => call_user_func_array($this->callbacks[$name], $args)
];
}
/**
* Set the list of matchers used by this parser
*
* @param MatcherInterface[]
* @return void
*/
public function setMatchers(array $matchers): void
{
$matchRegexps = [];
$this->groupMatches = [];
$this->matchGroups = [];
foreach ($this->getMatchersConfig($matchers) as $matchName => $matchConfig)
{
foreach ($matchConfig['groups'] as $group)
{
$this->groupMatches[$group][] = $matchName;
}
$regexp = $matchConfig['regexp'];
$regexp = $this->insertCaptureNames($matchName , $regexp);
$regexp = str_replace(' ', '\\s*+', $regexp);
$regexp = '(?<' . $matchName . '>' . $regexp . ')(*:' . $matchName . ')';
$matchRegexps[] = $regexp;
$this->callbacks[$matchName] = $matchConfig['callback'];
$this->matchGroups[$matchName] = $matchConfig['groups'];
}
$groupRegexps = [];
foreach ($this->groupMatches as $group => $names)
{
$groupRegexps[] = '(?<' . $group . '>(?&' . implode(')|(?&', $names) . '))';
}
$this->regexp = '((?(DEFINE)' . implode('', $groupRegexps). ')'
. '^(?:' . implode('|', $matchRegexps) . ')$)s';
}
/**
* Get the list of arguments produced by a regexp's match
*
* @param string[] $matches Regexp matches
* @param string $name Regexp name
* @return string[]
*/
protected function getArguments(array $matches, string $name): array
{
$args = [];
$i = 0;
while (isset($matches[$name . $i]))
{
$args[] = $matches[$name . $i];
++$i;
}
return $args;
}
/**
* Collect, normalize, sort and return the config for all matchers
*
* @param MatcherInterface[] $matchers
* @return array
*/
protected function getMatchersConfig(array $matchers): array
{
$matchersConfig = [];
foreach ($matchers as $matcher)
{
foreach ($matcher->getMatchers() as $matchName => $matchConfig)
{
if (is_string($matchConfig))
{
$matchConfig = ['regexp' => $matchConfig];
}
$parts = explode(':', $matchName);
$matchName = array_pop($parts);
$matchConfig += [
'callback' => [$matcher, 'parse' . $matchName],
'groups' => [],
'order' => 0
];
$matchConfig['name'] = $matchName;
$matchConfig['groups'] = array_unique(array_merge($matchConfig['groups'], $parts));
sort($matchConfig['groups']);
$matchersConfig[$matchName] = $matchConfig;
}
}
uasort($matchersConfig, 'static::sortMatcherConfig');
return $matchersConfig;
}
/**
* Insert capture names into given regexp
*
* @param string $name Name of the regexp, used to name captures
* @param string $regexp Original regexp
* @return string Modified regexp
*/
protected function insertCaptureNames(string $name, string $regexp): string
{
$i = 0;
return preg_replace_callback(
'((?<!\\\\)\\((?!\\?))',
function ($m) use (&$i, $name)
{
return '(?<' . $name . $i++ . '>';
},
$regexp
);
}
/**
* Compare two matchers' config
*
* @param array $a
* @param array $b
* @return integer
*/
protected static function sortMatcherConfig(array $a, array $b): int
{
if ($a['order'] !== $b['order'])
{
return $a['order'] - $b['order'];
}
return strcmp($a['name'], $b['name']);
}
}