<?php
/**
 * PHPCompatibility, an external standard for PHP_CodeSniffer.
 *
 * @package   PHPCompatibility
 * @copyright 2012-2019 PHPCompatibility Contributors
 * @license   https://opensource.org/licenses/LGPL-3.0 LGPL3
 * @link      https://github.com/PHPCompatibility/PHPCompatibility
 */

namespace PHPCompatibility\Sniffs\FunctionDeclarations;

use PHPCompatibility\AbstractNewFeatureSniff;
use PHP_CodeSniffer_File as File;

/**
 * Detect and verify the use of return type declarations in function declarations.
 *
 * Return type declarations are available since PHP 7.0.
 * - Since PHP 7.1, the `iterable` and `void` pseudo-types are available.
 * - Since PHP 7.2, the generic `object` type is available.
 *
 * PHP version 7.0+
 *
 * @link https://www.php.net/manual/en/migration70.new-features.php#migration70.new-features.return-type-declarations
 * @link https://www.php.net/manual/en/functions.returning-values.php#functions.returning-values.type-declaration
 * @link https://wiki.php.net/rfc/return_types
 * @link https://wiki.php.net/rfc/iterable
 * @link https://wiki.php.net/rfc/void_return_type
 * @link https://wiki.php.net/rfc/object-typehint
 *
 * @since 7.0.0
 * @since 7.1.0 Now extends the `AbstractNewFeatureSniff` instead of the base `Sniff` class.
 * @since 7.1.2 Renamed from `NewScalarReturnTypeDeclarationsSniff` to `NewReturnTypeDeclarationsSniff`.
 */
class NewReturnTypeDeclarationsSniff extends AbstractNewFeatureSniff {


	/**
	 * A list of new types
	 *
	 * The array lists : version number with false (not present) or true (present).
	 * If's sufficient to list the first version where the keyword appears.
	 *
	 * @since 7.0.0
	 *
	 * @var array(string => array(string => bool))
	 */
	protected $newTypes = array(
		'int'        => array(
			'5.6' => false,
			'7.0' => true,
		),
		'float'      => array(
			'5.6' => false,
			'7.0' => true,
		),
		'bool'       => array(
			'5.6' => false,
			'7.0' => true,
		),
		'string'     => array(
			'5.6' => false,
			'7.0' => true,
		),
		'array'      => array(
			'5.6' => false,
			'7.0' => true,
		),
		'callable'   => array(
			'5.6' => false,
			'7.0' => true,
		),
		'parent'     => array(
			'5.6' => false,
			'7.0' => true,
		),
		'self'       => array(
			'5.6' => false,
			'7.0' => true,
		),
		'Class name' => array(
			'5.6' => false,
			'7.0' => true,
		),

		'iterable'   => array(
			'7.0' => false,
			'7.1' => true,
		),
		'void'       => array(
			'7.0' => false,
			'7.1' => true,
		),

		'object'     => array(
			'7.1' => false,
			'7.2' => true,
		),
	);


	/**
	 * Returns an array of tokens this test wants to listen for.
	 *
	 * @since 7.0.0
	 * @since 7.1.2 Now also checks based on the function and closure keywords.
	 *
	 * @return array
	 */
	public function register() {
		$tokens = array(
			\T_FUNCTION,
			\T_CLOSURE,
		);

		if ( \defined( 'T_RETURN_TYPE' ) ) {
			$tokens[] = \T_RETURN_TYPE;
		}

		return $tokens;
	}


	/**
	 * Processes this test, when one of its tokens is encountered.
	 *
	 * @since 7.0.0
	 *
	 * @param \PHP_CodeSniffer_File $phpcsFile The file being scanned.
	 * @param int                   $stackPtr  The position of the current token in
	 *                                         the stack passed in $tokens.
	 *
	 * @return void
	 */
	public function process( File $phpcsFile, $stackPtr ) {
		$tokens = $phpcsFile->getTokens();

		// Deal with older PHPCS version which don't recognize return type hints
		// as well as newer PHPCS versions (3.3.0+) where the tokenization has changed.
		if ( $tokens[ $stackPtr ]['code'] === \T_FUNCTION || $tokens[ $stackPtr ]['code'] === \T_CLOSURE ) {
			$returnTypeHint = $this->getReturnTypeHintToken( $phpcsFile, $stackPtr );
			if ( $returnTypeHint !== false ) {
				$stackPtr = $returnTypeHint;
			}
		}

		if ( isset( $this->newTypes[ $tokens[ $stackPtr ]['content'] ] ) === true ) {
			$itemInfo = array(
				'name' => $tokens[ $stackPtr ]['content'],
			);
			$this->handleFeature( $phpcsFile, $stackPtr, $itemInfo );
		}
		// Handle class name based return types.
		elseif ( $tokens[ $stackPtr ]['code'] === \T_STRING
			|| ( \defined( 'T_RETURN_TYPE' ) && $tokens[ $stackPtr ]['code'] === \T_RETURN_TYPE )
		) {
			$itemInfo = array(
				'name' => 'Class name',
			);
			$this->handleFeature( $phpcsFile, $stackPtr, $itemInfo );
		}
	}


	/**
	 * Get the relevant sub-array for a specific item from a multi-dimensional array.
	 *
	 * @since 7.1.0
	 *
	 * @param array $itemInfo Base information about the item.
	 *
	 * @return array Version and other information about the item.
	 */
	public function getItemArray( array $itemInfo ) {
		return $this->newTypes[ $itemInfo['name'] ];
	}


	/**
	 * Get the error message template for this sniff.
	 *
	 * @since 7.1.0
	 *
	 * @return string
	 */
	protected function getErrorMsgTemplate() {
		return '%s return type is not present in PHP version %s or earlier';
	}
}
