<?php declare(strict_types=1);
namespace PhpParser;
class JsonDecoder
{
/** @var \ReflectionClass[] Node type to reflection class map */
private $reflectionClassCache;
public function decode(string $json) {
$value = json_decode($json, true);
if (json_last_error()) {
throw new \RuntimeException('JSON decoding error: ' . json_last_error_msg());
}
return $this->decodeRecursive($value);
}
private function decodeRecursive($value) {
if (\is_array($value)) {
if (isset($value['nodeType'])) {
if ($value['nodeType'] === 'Comment' || $value['nodeType'] === 'Comment_Doc') {
return $this->decodeComment($value);
}
return $this->decodeNode($value);
}
return $this->decodeArray($value);
}
return $value;
}
private function decodeArray(array $array) : array {
$decodedArray = [];
foreach ($array as $key => $value) {
$decodedArray[$key] = $this->decodeRecursive($value);
}
return $decodedArray;
}
private function decodeNode(array $value) : Node {
$nodeType = $value['nodeType'];
if (!\is_string($nodeType)) {
throw new \RuntimeException('Node type must be a string');
}
$reflectionClass = $this->reflectionClassFromNodeType($nodeType);
/** @var Node $node */
$node = $reflectionClass->newInstanceWithoutConstructor();
if (isset($value['attributes'])) {
if (!\is_array($value['attributes'])) {
throw new \RuntimeException('Attributes must be an array');
}
$node->setAttributes($this->decodeArray($value['attributes']));
}
foreach ($value as $name => $subNode) {
if ($name === 'nodeType' || $name === 'attributes') {
continue;
}
$node->$name = $this->decodeRecursive($subNode);
}
return $node;
}
private function decodeComment(array $value) : Comment {
$className = $value['nodeType'] === 'Comment' ? Comment::class : Comment\Doc::class;
if (!isset($value['text'])) {
throw new \RuntimeException('Comment must have text');
}
return new $className(
$value['text'],
$value['line'] ?? -1, $value['filePos'] ?? -1, $value['tokenPos'] ?? -1,
$value['endLine'] ?? -1, $value['endFilePos'] ?? -1, $value['endTokenPos'] ?? -1
);
}
private function reflectionClassFromNodeType(string $nodeType) : \ReflectionClass {
if (!isset($this->reflectionClassCache[$nodeType])) {
$className = $this->classNameFromNodeType($nodeType);
$this->reflectionClassCache[$nodeType] = new \ReflectionClass($className);
}
return $this->reflectionClassCache[$nodeType];
}
private function classNameFromNodeType(string $nodeType) : string {
$className = 'PhpParser\\Node\\' . strtr($nodeType, '_', '\\');
if (class_exists($className)) {
return $className;
}
$className .= '_';
if (class_exists($className)) {
return $className;
}
throw new \RuntimeException("Unknown node type \"$nodeType\"");
}
}