<?php

/**
 * Class WPML_Backend_Request
 *
 * @package    wpml-core
 * @subpackage wpml-requests
 */
class WPML_Backend_Request extends WPML_Request {

	public function __construct( $active_languages, $default_language ) {
		parent::__construct( $active_languages, $default_language );
		global $wpml_url_filters;

		if ( strpos( (string) filter_var( $_SERVER[ 'REQUEST_URI' ] ), 'wpml_root_page=1' ) !== false
			 || $wpml_url_filters->frontend_uses_root() !== false
		) {
			require_once ICL_PLUGIN_PATH . '/inc/url-handling/wpml-root-page.class.php';
		}
	}

	public function check_if_admin_action_from_referer() {
		$referer = isset( $_SERVER[ 'HTTP_REFERER' ] ) ? $_SERVER[ 'HTTP_REFERER' ] : '';

		return strpos( $referer, strtolower( '/wp-admin/' ) ) !== false;
	}

	private function force_default() {
		return isset( $_GET[ 'page' ] )
			   && ( ( defined( 'WPML_ST_FOLDER' )
					  && $_GET[ 'page' ] === WPML_ST_FOLDER . '/menu/string-translation.php' )
					|| ( defined( 'WPML_TM_FOLDER' )
						 && $_GET[ 'page' ] === WPML_TM_FOLDER . '/menu/translations-queue.php' ) );
	}

	/**
	 * Gets the source_language $_GET parameter from the HTTP_REFERER
	 *
	 * @return string|bool
	 */
	public function get_source_language_from_referer() {
		$referer = isset( $_SERVER[ 'HTTP_REFERER' ] ) ? $_SERVER[ 'HTTP_REFERER' ] : '';
		$query   = parse_url( $referer, PHP_URL_QUERY );
		parse_str( $query, $query_parts );
		$source_lang = isset( $query_parts[ 'source_lang' ] ) ? $query_parts[ 'source_lang' ] : false;

		return $source_lang;
	}

	private function get_ajax_request_lang() {
		global $wpml_url_converter;

		$al   = $this->active_languages;
		$lang = isset( $_POST[ 'lang' ] ) && isset( $al[ $_POST[ 'lang' ] ] ) ? $_POST[ 'lang' ] : null;
		$lang = $lang === null ? ( $cookie_lang = $this->get_cookie_lang() ) : $lang;
		$lang = $lang === null && isset( $_SERVER[ 'HTTP_REFERER' ] )
			? $wpml_url_converter->get_language_from_url( $_SERVER[ 'HTTP_REFERER' ] ) : $lang;
		$lang = $lang ? $lang : ( isset( $cookie_lang ) ? $cookie_lang : $this->get_cookie_lang() );
		$lang = $lang ? $lang : $this->default_language;

		return $lang;
	}

	/**
	 * Determines the requested language in the WP Admin backend from URI, $_POST, $_GET and cookies.
	 *
	 * @return string requested language code
	 */
	public function get_requested_lang() {
		/**
		 * @var WPML_Language_Resolution $wpml_language_resolution
		 * @var WPML_Post_Translation    $wpml_post_translations
		 */
		global $wpml_language_resolution, $wpml_post_translations;

		if ( $this->force_default() === true ) {
			$lang = $this->default_language;
		} elseif ( isset( $_GET[ 'lang' ] )
				   && $wpml_language_resolution->is_language_active( $_GET[ 'lang' ], true )
		) {
			$lang = $_GET[ 'lang' ];
		} elseif ( wpml_is_ajax() ) {
			$lang = $this->get_ajax_request_lang();
		} elseif ( isset( $_POST[ 'icl_post_language' ] )
				   && $wpml_language_resolution->is_language_active( $_POST[ 'icl_post_language' ] )
		) {
			$lang = $_POST[ 'icl_post_language' ];
		} elseif ( isset( $_GET[ 'p' ] )
				   && ( $p = (int) $_GET[ 'p' ] ) > 0
				   && (bool) ( $posts_lang = $wpml_post_translations->get_element_lang_code( $p ) ) === true
		) {
			$lang = $posts_lang;
		} else {
			$lang = $this->get_cookie_lang();
		}

		return $lang;
	}

	protected function get_cookie_name() {

		return wpml_is_ajax() && $this->check_if_admin_action_from_referer() === false
			? '_icl_current_language' : '_icl_current_admin_language';
	}
}