<?php
/**
* @see https://github.com/laminas/laminas-mail for the canonical source repository
* @copyright https://github.com/laminas/laminas-mail/blob/master/COPYRIGHT.md
* @license https://github.com/laminas/laminas-mail/blob/master/LICENSE.md New BSD License
*/
namespace Laminas\Mail\Header;
use function in_array;
/**
* @internal
*/
class ListParser
{
const CHAR_QUOTES = ['\'', '"'];
const CHAR_DELIMS = [',', ';'];
const CHAR_ESCAPE = '\\';
/**
* @param string $value
* @param array $delims Delimiters allowed between values; parser will
* split on these, as long as they are not within quotes. Defaults
* to ListParser::CHAR_DELIMS.
* @return array
*/
public static function parse($value, array $delims = self::CHAR_DELIMS)
{
$values = [];
$length = strlen($value);
$currentValue = '';
$inEscape = false;
$inQuote = false;
$currentQuoteDelim = null;
for ($i = 0; $i < $length; $i += 1) {
$char = $value[$i];
// If we are in an escape sequence, append the character and continue.
if ($inEscape) {
$currentValue .= $char;
$inEscape = false;
continue;
}
// If we are not in a quoted string, and have a delimiter, append
// the current value to the list, and reset the current value.
if (in_array($char, $delims, true) && ! $inQuote) {
$values [] = $currentValue;
$currentValue = '';
continue;
}
// Append the character to the current value
$currentValue .= $char;
// Escape sequence discovered.
if (self::CHAR_ESCAPE === $char) {
$inEscape = true;
continue;
}
// If the character is not a quote character, we are done
// processing it.
if (! in_array($char, self::CHAR_QUOTES)) {
continue;
}
// If the character matches a previously matched quote delimiter,
// we reset our quote status and the currently opened quote
// delimiter.
if ($char === $currentQuoteDelim) {
$inQuote = false;
$currentQuoteDelim = null;
continue;
}
// If already in quote and the character does not match the previously
// matched quote delimiter, we're done here.
if ($inQuote) {
continue;
}
// Otherwise, we're starting a quoted string.
$inQuote = true;
$currentQuoteDelim = $char;
}
// If we reached the end of the string and still have a current value,
// append it to the list (no delimiter was reached).
if ('' !== $currentValue) {
$values [] = $currentValue;
}
return $values;
}
}