nextcloud-server/lib/private/AppFramework/Utility/ControllerMethodReflector.php

<?php

declare(strict_types=1);
/**
 * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
 * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
 * SPDX-License-Identifier: AGPL-3.0-only
 */

namespace OC\AppFramework\Utility;

use OCP\AppFramework\Utility\IControllerMethodReflector;
use Psr\Log\LoggerInterface;

/**
 * Reads and parses annotations from doc comments
 */
class ControllerMethodReflector implements IControllerMethodReflector {
	public array $annotations = [];
	private array $types = [];
	private array $parameters = [];
	private array $ranges = [];
	private array $stringConstraints = [];
	private int $startLine = 0;
	private string $file = '';
	private ?\ReflectionMethod $reflectionMethod = null;

	public function __construct(
		private readonly LoggerInterface $logger,
	) {
	}

	/**
	 * @param object $object an object or classname
	 * @param string $method the method which we want to inspect
	 */
	public function reflect($object, string $method) {
		$this->annotations = [];
		$this->types = [];
		$this->parameters = [];
		$this->ranges = [];
		$this->stringConstraints = [];
		$this->reflectionMethod = new \ReflectionMethod($object, $method);
		$this->startLine = $this->reflectionMethod->getStartLine();
		$this->file = $this->reflectionMethod->getFileName();

		$docs = $this->reflectionMethod->getDocComment();

		if ($docs !== false) {
			// extract everything prefixed by @ and first letter uppercase
			preg_match_all('/^\h+\*\h+@(?P<annotation>[A-Z]\w+)((?P<parameter>.*))?$/m', $docs, $matches);
			foreach ($matches['annotation'] as $key => $annotation) {
				$annotation = strtolower($annotation);
				$annotationValue = $matches['parameter'][$key];
				if (str_starts_with($annotationValue, '(') && str_ends_with($annotationValue, ')')) {
					$cutString = substr($annotationValue, 1, -1);
					$cutString = str_replace(' ', '', $cutString);
					$splitArray = explode(',', $cutString);
					foreach ($splitArray as $annotationValues) {
						[$key, $value] = explode('=', $annotationValues);
						$this->annotations[$annotation][$key] = $value;
					}
					continue;
				}

				$this->annotations[$annotation] = [$annotationValue];
			}

			// extract type parameter information
			preg_match_all('/@param\h+(?P<type>\w+)\h+\$(?P<var>\w+)/', $docs, $matches);
			$this->types = array_combine($matches['var'], $matches['type']);
			preg_match_all('/@(?:psalm-)?param\h+(\?)?(?P<type>\w+)<(?P<rangeMin>(-?\d+|min)),\h*(?P<rangeMax>(-?\d+|max))>(\|null)?\h+\$(?P<var>\w+)/', $docs, $matches);
			foreach ($matches['var'] as $index => $varName) {
				if ($matches['type'][$index] !== 'int') {
					// only int ranges are possible at the moment
					// @see https://psalm.dev/docs/annotating_code/type_syntax/scalar_types
					continue;
				}
				$this->ranges[$varName] = [
					'min' => $matches['rangeMin'][$index] === 'min' ? PHP_INT_MIN : (int)$matches['rangeMin'][$index],
					'max' => $matches['rangeMax'][$index] === 'max' ? PHP_INT_MAX : (int)$matches['rangeMax'][$index],
				];
			}

			// extract psalm int aliases that imply a fixed range
			preg_match_all('/@(?:psalm-)?param\h+(\?)?(?P<type>positive-int|non-negative-int|negative-int|non-positive-int)(\|null)?\h+\$(?P<var>\w+)/', $docs, $matches);
			foreach ($matches['var'] as $index => $varName) {
				$this->ranges[$varName] = match ($matches['type'][$index]) {
					'positive-int' => ['min' => 1, 'max' => PHP_INT_MAX],
					'non-negative-int' => ['min' => 0, 'max' => PHP_INT_MAX],
					'negative-int' => ['min' => PHP_INT_MIN, 'max' => -1],
					'non-positive-int' => ['min' => PHP_INT_MIN, 'max' => 0],
				};
			}

			// extract psalm scalar string types
			preg_match_all('/@(?:psalm-)?param\h+(\?)?(?P<type>non-empty-lowercase-string|non-falsy-string|non-empty-string|lowercase-string|numeric-string)(\|null)?\h+\$(?P<var>\w+)/', $docs, $matches);
			foreach ($matches['var'] as $index => $varName) {
				$this->stringConstraints[$varName] = $matches['type'][$index];
			}
		}

		foreach ($this->reflectionMethod->getParameters() as $param) {
			// extract type information from PHP 7 scalar types and prefer them over phpdoc annotations
			$type = $param->getType();
			if ($type instanceof \ReflectionNamedType) {
				$this->types[$param->getName()] = $type->getName();
			}

			$default = null;
			if ($param->isOptional()) {
				$default = $param->getDefaultValue();
			}
			$this->parameters[$param->name] = $default;
		}
	}

	/**
	 * Inspects the PHPDoc parameters for types
	 * @param string $parameter the parameter whose type comments should be
	 *                          parsed
	 * @return string|null type in the type parameters (@param int $something)
	 *                     would return int or null if not existing
	 */
	#[\Override]
	public function getType(string $parameter) {
		if (array_key_exists($parameter, $this->types)) {
			return $this->types[$parameter];
		}

		return null;
	}

	public function getRange(string $parameter): ?array {
		if (array_key_exists($parameter, $this->ranges)) {
			return $this->ranges[$parameter];
		}

		return null;
	}

	public function getStringConstraint(string $parameter): ?string {
		return $this->stringConstraints[$parameter] ?? null;
	}

	/**
	 * Whether $value satisfies the psalm string type annotated for $parameter,
	 * or true if none was annotated
	 */
	public function satisfiesStringConstraint(string $parameter, string $value): bool {
		return match ($this->getStringConstraint($parameter)) {
			'non-empty-string' => $value !== '',
			'non-empty-lowercase-string' => $value !== '' && $value === strtolower($value),
			'lowercase-string' => $value === strtolower($value),
			'non-falsy-string' => $value !== '' && $value !== '0',
			'numeric-string' => is_numeric($value),
			default => true,
		};
	}

	/**
	 * @return array the arguments of the method with key => default value
	 */
	#[\Override]
	public function getParameters(): array {
		return $this->parameters;
	}

	/**
	 * @template T
	 *
	 * @param class-string<T> $attributeClass
	 */
	#[\Override]
	public function hasAnnotationOrAttribute(?string $annotationName, string $attributeClass): bool {
		if (!empty($this->reflectionMethod->getAttributes($attributeClass))) {
			return true;
		}

		if ($annotationName && $this->hasAnnotation($annotationName)) {
			$this->logger->debug($this->reflectionMethod->getDeclaringClass()->getName() . '::' . $this->reflectionMethod->getName() . ' uses the @' . $annotationName . ' annotation and should use the #[' . $attributeClass . '] attribute instead');
			return true;
		}

		return false;
	}

	/**
	 * @template T
	 * @param class-string<T> $attributeClass
	 * @return ?\ReflectionAttribute<T>
	 */
	public function getAttribute(string $attributeClass): ?\ReflectionAttribute {
		$attributes = $this->reflectionMethod->getAttributes($attributeClass);
		if (!empty($attributes)) {
			return $attributes[0];
		}
		return null;
	}

	/**
	 * Check if a method contains an annotation
	 * @param string $name the name of the annotation
	 * @return bool true if the annotation is found
	 */
	#[\Override]
	public function hasAnnotation(string $name): bool {
		$name = strtolower($name);
		return array_key_exists($name, $this->annotations);
	}

	/**
	 * Get optional annotation parameter by key
	 *
	 * @param string $name the name of the annotation
	 * @param string $key the string of the annotation
	 * @return string
	 */
	public function getAnnotationParameter(string $name, string $key): string {
		$name = strtolower($name);
		if (isset($this->annotations[$name][$key])) {
			return $this->annotations[$name][$key];
		}

		return '';
	}

	public function getStartLine(): int {
		return $this->startLine;
	}

	public function getFile(): string {
		return $this->file;
	}
}