customfields.php

<?php
/**
 * @version     1.0.0
 * @package     PLG_Content_CustomFields
 * @copyright   Copyright (C) 2024. All rights reserved.
 * @license     http://www.gnu.org/licenses/gpl-2.0.html GNU/GPL
 * @author      Custom Plugin
 */

// No Direct Access
defined('_JEXEC') || die('Restricted access');

use Joomla\CMS\Factory;
use Joomla\CMS\Plugin\CMSPlugin;
use Joomla\CMS\User\User;

/**
 * Custom Fields Shortcode Plugin
 *
 * This plugin processes shortcodes like [CF fieldname] and replaces them
 * with the actual value of the custom user field.
 */
class PlgContentCustomfields extends CMSPlugin
{
    /**
     * Application object.
     *
     * @var    \Joomla\CMS\Application\CMSApplication
     * @since  1.0.0
     */
    protected $app;

    /**
     * Load the language file on instantiation.
     *
     * @var    boolean
     * @since  1.0.0
     */
    protected $autoloadLanguage = true;

    /**
     * Plugin that processes custom field shortcodes
     *
     * @param   string   $context  The context of the content being passed
     * @param   object   &$article The article object
     * @param   object   &$params  The article params
     * @param   integer  $page     The 'page' number
     *
     * @return  void
     *
     * @since   1.0.0
     */
    public function onContentPrepare($context, &$article, &$params, $page = 0)
    {
        // Check if we should process this content
        if (!$this->shouldProcess($context, $article)) {
            return;
        }

        // Get the current user
        $user = $this->app->getIdentity();

        // Only process if user is logged in
        if ($user->guest) {
            // Replace shortcodes with guest text or remove them
            $guestText = $this->params->get('guest_text', '');
            $article->text = preg_replace('/\[CF\s+([^\]]+)\]/i', $guestText, $article->text);
            return;
        }

        // Process shortcodes for logged in users
        $article->text = preg_replace_callback(
            '/\[CF\s+([^\]]+)\]/i',
            [$this, 'processShortcode'],
            $article->text
        );
    }

    /**
     * Check if we should process this content
     *
     * @param   string  $context  The context
     * @param   object  $article  The article object
     *
     * @return  boolean
     *
     * @since   1.0.0
     */
    protected function shouldProcess($context, &$article)
    {
        // Skip if disabled
        if (!$this->params->get('enabled', 1)) {
            return false;
        }

        // Skip if no article or text to process
        if (empty($article) || empty($article->text)) {
            return false;
        }

        // Skip if no shortcodes found
        if (strpos($article->text, '[CF ') === false) {
            return false;
        }

        // Check if context is allowed
        $allowedContexts = $this->getAllowedContexts();
        if (!empty($allowedContexts) && !in_array($context, $allowedContexts)) {
            return false;
        }

        return true;
    }

    /**
     * Get allowed contexts from plugin parameters
     *
     * @return  array
     *
     * @since   1.0.0
     */
    protected function getAllowedContexts()
    {
        $contextsParam = $this->params->get('contexts', '');
        
        if (empty($contextsParam)) {
            // Return default contexts if none specified
            return [
                'com_content.article',
                'com_content.category',
                'com_users.user'
            ];
        }

        // Parse contexts from textarea (one per line)
        $contexts = array_filter(
            array_map('trim', explode("\n", $contextsParam)),
            function($context) {
                return !empty($context);
            }
        );

        return $contexts;
    }

    /**
     * Process individual shortcode
     *
     * @param   array  $matches  The regex matches
     *
     * @return  string  The replacement text
     *
     * @since   1.0.0
     */
    protected function processShortcode($matches)
    {
        $fieldName = trim($matches[1]);
        
        if (empty($fieldName)) {
            return $matches[0]; // Return original shortcode if no field name
        }

        try {
            $user = $this->app->getIdentity();
            $fieldValue = $this->getCustomFieldValue($user->id, $fieldName);
            
            if ($fieldValue !== null && $fieldValue !== '') {
                return $this->formatFieldValue($fieldValue, $fieldName);
            }
            
            // Return default text if field not found or empty
            $defaultText = $this->params->get('default_text', '');
            return !empty($defaultText) ? $defaultText : $matches[0];
            
        } catch (Exception $e) {
            // Log error if debug is enabled
            if ($this->params->get('debug', 0)) {
                Factory::getApplication()->enqueueMessage(
                    'Custom Fields Plugin Error: ' . $e->getMessage(),
                    'error'
                );
            }
            
            return $matches[0]; // Return original shortcode on error
        }
    }

    /**
     * Get custom field value for a user
     *
     * @param   integer  $userId     The user ID
     * @param   string   $fieldName  The field name
     *
     * @return  mixed    The field value or null if not found
     *
     * @since   1.0.0
     */
    protected function getCustomFieldValue($userId, $fieldName)
    {
        try {
            $db = Factory::getDbo();
            
            // Search for field by name or title
            $query = $db->getQuery(true)
                ->select('f.id, f.name, f.title, f.type, fv.value')
                ->from('#__fields AS f')
                ->leftJoin('#__fields_values AS fv ON f.id = fv.field_id AND fv.item_id = ' . (int) $userId)
                ->where('f.context = ' . $db->quote('com_users.user'))
                ->where('f.state = 1')
                ->where('(f.name = ' . $db->quote($fieldName) . ' OR f.title = ' . $db->quote($fieldName) . ')');

            $result = $db->setQuery($query)->loadObject();
            
            if ($result && isset($result->value) && $result->value !== '') {
                return $result->value;
            }
            
        } catch (Exception $e) {
            if ($this->params->get('debug', 0)) {
                Factory::getApplication()->enqueueMessage(
                    'Database Error in Custom Fields Plugin: ' . $e->getMessage(),
                    'error'
                );
            }
        }
        
        return null;
    }

    /**
     * Format field value for display
     *
     * @param   mixed   $value      The field value
     * @param   string  $fieldName  The field name
     *
     * @return  string  The formatted value
     *
     * @since   1.0.0
     */
    protected function formatFieldValue($value, $fieldName)
    {
        // Handle JSON values (for list fields, checkboxes, etc.)
        if (is_string($value) && $this->isJson($value)) {
            $decoded = json_decode($value, true);
            if (is_array($decoded)) {
                // Join array values with commas
                return implode(', ', array_filter($decoded));
            }
        }
        
        // Apply HTML output setting
        $htmlOutput = $this->params->get('html_output', 0);
        
        if ($htmlOutput) {
            return $value; // Allow HTML
        } else {
            return htmlspecialchars($value, ENT_QUOTES, 'UTF-8'); // Escape HTML
        }
    }

    /**
     * Check if string is valid JSON
     *
     * @param   string  $string  The string to check
     *
     * @return  boolean
     *
     * @since   1.0.0
     */
    protected function isJson($string)
    {
        if (!is_string($string) || empty($string)) {
            return false;
        }
        
        json_decode($string);
        return json_last_error() === JSON_ERROR_NONE;
    }
}