/**
* Returns the decoded array from $str
* @throws an IllegalArgumentException in the case
* that the string is malformed.
*/
public static function toArray($str)
{
if (substr($str, 0, 1) != "d" || substr($str, -1, 1) != "e") {
throw new IllegalArgumentException("BEncoded dictionary does not start with d or end with e.");
}
// An array is simply two lists encoded in an alternating list
$arrays = BList::toList("l" . substr($str, 1));
$i = 0;
for ($i = 0; $i < sizeof($arrays); $i += 2) {
$array[$arrays[$i]] = $arrays[$i + 1];
}
return $array;
}
/**
* Returns the decoded array from $str
* @throws an IllegalArgumentException in the case
* that the string is malformed.
*/
public static function toList($str)
{
if (substr($str, 0, 1) != "l" || substr($str, -1, 1) != "e") {
throw new IllegalArgumentException("BEncoded list does not start with l or end with e.");
}
$value = substr($str, 1, -1);
// Scan through encoded list and decode everything
$list = array();
$i = 0;
$lastI = 0;
while ($i < strlen($value)) {
$curChar = substr($value, $i, 1);
if ($curChar == "i") {
// We just saw an Integer
$endPos = strpos($value, "e", $i);
// Search for the end of it
if ($endPos === false) {
throw new IllegalArgumentException("BEncoded list contains non-terminated integer");
}
$list[] = BInteger::toInteger(substr($value, $i, $endPos - $i + 1));
$i = $endPos + 1;
} elseif (is_numeric($curChar)) {
// A number means we just saw a string starting
$seperatorPos = strpos($value, ":", $i);
// Search for the seperator
if ($seperatorPos === false) {
throw new IllegalArgumentException("BEncoded list contains malformed string with no length specified");
}
$totalLength = substr($value, $i, $seperatorPos - $i);
$list[] = BString::toString(substr($value, $i, $seperatorPos - $i + $totalLength + 1));
$i = $seperatorPos + $totalLength + 1;
} elseif ($curChar == "d" || $curChar == "l") {
// Found a dictionary or list
// Scan for end of it
$listLength = BList::getListLength(substr($value, $i));
if ($curChar == "d") {
$list[] = BDictionary::toArray(substr($value, $i, $listLength));
} else {
$list[] = BList::toList(substr($value, $i, $listLength));
}
$i += $listLength;
}
if ($i == $lastI) {
throw new IllegalArgumentException("BEncoded list contains malfomed or unrecognized content");
}
$lastI = $i;
}
return $list;
}
