<?php

namespace wcf\system\template\plugin;

use wcf\system\exception\SystemException;
use wcf\system\request\RequestHandler;
use wcf\system\template\TemplateEngine;
use wcf\system\WCF;
use wcf\util\StringUtil;

/**
 * Template function plugin which generates script tags. File extension is automatically
 * added to the script source and MUST NOT be provided.
 *
 * If ENABLE_DEBUG_MODE=0 then the extension is '.min.js', don't fail to provide it.
 *
 * The option VISITOR_USE_TINY_BUILD enables a specialized build, that is designed to
 * provide smaller builds for visitors in order to decrease the overall payload and
 * reduce page load time. Supporting them is optional and can be supplied by setting
 * `hasTiny=true`, the extension is assumed to be `.tiny.min.js`.
 *
 * Usage:
 *  {js application='wbb' file='WBB'}
 *  http://example.com/js/WBB.js
 *
 *  {js application='wcf' file='WCF.User' bundle='WCF.Combined'}
 *  http://example.com/wcf/js/WCF.User.js (ENABLE_DEBUG_MODE=1)
 *  http://example.com/wcf/js/WCF.Combined.min.js (ENABLE_DEBUG_MODE=0)
 *
 *  {js application='wcf' lib='jquery'}
 *  http://example.com/wcf/js/3rdParty/jquery.js
 *
 *  {js application='wcf' lib='jquery-ui' file='awesomeWidget'}
 *  http://example.com/wcf/js/3rdParty/jquery-ui/awesomeWidget.js
 *
 *      {js application='wcf' file='WCF.User' bundle='WCF.Combined' hasTiny=true}
 *  http://example.com/wcf/js/WCF.User.js (ENABLE_DEBUG_MODE=1)
 *  http://example.com/wcf/js/WCF.Combined.min.js (ENABLE_DEBUG_MODE=0)
 *      http://example.com/wcf/js/WCF.Combined.tiny.min.js (ENABLE_DEBUG_MODE=0 && VISITOR_USE_TINY_BUILD=1)
 *
 * @author  Alexander Ebert
 * @copyright   2001-2019 WoltLab GmbH
 * @license GNU Lesser General Public License <http://opensource.org/licenses/lgpl-license.php>
 * @since   3.0
 */
class JsFunctionTemplatePlugin implements IFunctionTemplatePlugin
{
    /**
     * list of already included JavaScript files
     * @var string[]
     */
    protected $includedFiles = [];

    /**
     * @inheritDoc
     */
    public function execute($tagArgs, TemplateEngine $tplObj)
    {
        // needed arguments: application and lib/file
        if (empty($tagArgs['application'])) {
            throw new SystemException("missing 'application' argument in js tag");
        }
        if (empty($tagArgs['file']) && empty($tagArgs['lib'])) {
            throw new SystemException("missing 'file' or 'lib' argument in js tag");
        }

        $isJquery = false;
        if (
            isset($tagArgs['lib'])
            && ($tagArgs['lib'] === 'jquery' || $tagArgs['lib'] === 'jquery-ui')
            && empty($tagArgs['file'])
        ) {
            $tagArgs['bundle'] = '';
            $isJquery = true;
        }

        $src = WCF::getPath($tagArgs['application']) . (isset($tagArgs['acp']) && $tagArgs['acp'] === 'true' ? 'acp/' : '') . 'js/';
        if (!empty($tagArgs['bundle']) && !ENABLE_DEBUG_MODE) {
            $src .= $tagArgs['bundle'];
        } elseif (!empty($tagArgs['lib'])) {
            if ($isJquery) {
                $src .= ENABLE_DEBUG_MODE ? '3rdParty/' . $tagArgs['lib'] : 'WCF.Combined';
            } else {
                $src .= '3rdParty/' . $tagArgs['lib'];
                if (!empty($tagArgs['file'])) {
                    $src .= '/' . $tagArgs['file'];
                }
            }
        } else {
            $src .= $tagArgs['file'];
        }

        if (isset($this->includedFiles[$src])) {
            return '';
        }

        $this->includedFiles[$src] = true;
        if (!ENABLE_DEBUG_MODE) {
            if (
                \defined('VISITOR_USE_TINY_BUILD')
                && VISITOR_USE_TINY_BUILD
                && !WCF::getUser()->userID
                && !empty($tagArgs['hasTiny'])
            ) {
                $src .= '.tiny';
            }

            $src .= '.min';
        }
        $src .= '.js?v=' . LAST_UPDATE_TIME;

        $relocate = !RequestHandler::getInstance()->isACPRequest() && (!isset($tagArgs['core']) || $tagArgs['core'] !== 'true');
        $html = '<script' . ($relocate ? ' data-relocate="true"' : '') . ' data-cfasync="false" src="' . $src . '"></script>' . "\n";

        if (isset($tagArgs['encodeJs']) && $tagArgs['encodeJs'] === 'true') {
            $html = StringUtil::encodeJS($html);
        }

        return $html;
    }
}