<?php

namespace MediaWiki\Extension\Gadgets\Content;

use MediaWiki\Status\Status;

/**
 * Class responsible for validating Gadget definition contents
 *
 * @todo maybe this should use a formal JSON schema validator or something
 */
class GadgetDefinitionValidator {
	/**
	 * @var array Validation metadata.
	 * 'foo.bar.baz' => [ 'type check callback',
	 *   'type name' [, 'member type check callback', 'member type name'] ]
	 */
	protected static $propertyValidation = [
		'settings' => [ 'is_array', 'array' ],
		'settings.actions' => [ 'is_array', 'array', 'is_string', 'string' ],
		'settings.categories' => [ 'is_array', 'array', 'is_string', 'string' ],
		'settings.category' => [ 'is_string', 'string' ],
		'settings.contentModels' => [ 'is_array', 'array', 'is_string', 'string' ],
		'settings.default' => [ 'is_bool', 'boolean' ],
		'settings.hidden' => [ 'is_bool', 'boolean' ],
		'settings.namespaces' => [ 'is_array', 'array', 'is_int', 'integer' ],
		'settings.package' => [ 'is_bool', 'boolean' ],
		'settings.requiresES6' => [ 'is_bool', 'boolean' ],
		'settings.rights' => [ 'is_array', 'array', 'is_string', 'string' ],
		'settings.skins' => [ 'is_array', 'array', 'is_string', 'string' ],
		'settings.supportsUrlLoad' => [ 'is_bool', 'boolean' ],

		'module' => [ 'is_array', 'array' ],
		'module.dependencies' => [ 'is_array', 'array', 'is_string', 'string' ],
		'module.messages' => [ 'is_array', 'array', 'is_string', 'string' ],
		'module.pages' => [ 'is_array', 'array', [ __CLASS__, 'isValidTitleSuffix' ], '.js, .css or .json page' ],
		'module.peers' => [ 'is_array', 'array', 'is_string', 'string' ],
		'module.type' => [ [ __CLASS__, 'isValidType' ], 'general or styles' ],
	];

	public static function isValidTitleSuffix( string $title ): bool {
		return str_ends_with( $title, '.js' ) || str_ends_with( $title, '.css' ) || str_ends_with( $title, '.json' );
	}

	public static function isValidType( string $type ): bool {
		return $type === '' || $type === 'general' || $type === 'styles';
	}

	/**
	 * Check the validity of the given properties array
	 * @param array $properties Return value of FormatJson::decode( $blob, true )
	 * @param bool $tolerateMissing If true, don't complain about missing keys
	 * @return Status object with error message if applicable
	 */
	public function validate( array $properties, $tolerateMissing = false ) {
		foreach ( self::$propertyValidation as $property => $validation ) {
			$path = explode( '.', $property );
			$val = $properties;

			// Walk down and verify that the path from the root to this property exists
			foreach ( $path as $p ) {
				if ( !array_key_exists( $p, $val ) ) {
					if ( $tolerateMissing ) {
						// Skip validation of this property altogether
						continue 2;
					}

					return Status::newFatal( 'gadgets-validate-notset', $property );
				}
				$val = $val[$p];
			}

			// Do the actual validation of this property
			$func = $validation[0];
			if ( !call_user_func( $func, $val ) ) {
				return Status::newFatal(
					'gadgets-validate-wrongtype',
					$property,
					$validation[1],
					gettype( $val )
				);
			}

			if ( isset( $validation[2] ) && isset( $validation[3] ) && is_array( $val ) ) {
				// Descend into the array and check the type of each element
				$func = $validation[2];
				foreach ( $val as $i => $v ) {
					if ( !call_user_func( $func, $v ) ) {
						return Status::newFatal(
							'gadgets-validate-wrongtype',
							"{$property}[{$i}]",
							$validation[3],
							gettype( $v )
						);
					}
				}
			}
		}

		return Status::newGood();
	}
}