<?php
/**
 * @package     VikRentCar
 * @subpackage  com_vikrentcar
 * @author      Alessio Gaggii - E4J srl
 * @copyright   Copyright (C) 2024 E4J srl. All rights reserved.
 * @license     GNU General Public License version 2 or later; see LICENSE
 * @link        https://vikwp.com
 */

defined('ABSPATH') or die('No script kiddies please!');

/**
 * Helper class to render specific param types.
 * 
 * @since   1.15.9 (J) - 1.4.6 (WP)
 */
final class VRCParamsRendering
{
    /**
     * @var  array
     */
    private $params = [];

    /**
     * @var  array
     */
    private $settings = [];

    /**
     * @var  array
     */
    private $scripts = [];

    /**
     * @var  array
     */
    private $assets = [];

    /**
     * @var  string
     */
    private $inputName = 'vrcparams';

    /**
     * @var     int
     */
    private static $instance_counter = -1;

    /**
     * Class constructor is protected.
     * 
     * @param   array    $params   The form params to bind.
     * @param   array    $settings The form settings to bind.
     * 
     * @see     getInstance()
     */
    private function __construct(array $params, array $settings)
    {
        // bind values
        $this->params   = $params;
        $this->settings = $settings;

        // increase instance counter
        static::$instance_counter++;
    }

    /**
     * Proxy for immediately accessing the object and bind data.
     * 
     * @param   array    $params   The form params to bind.
     * @param   array    $settings The form settings to bind.
     * 
     * @return  VRCParamsRendering
     */
    public static function getInstance(array $params = [], array $settings = [])
    {
        return new static($params, $settings);
    }

    /**
     * Sets the name to be used for rendering the param fields.
     * 
     * @param   string  $name   The name to use.
     * 
     * @return  self
     */
    public function setInputName($name)
    {
        $this->inputName = (string) $name;

        return $this;
    }

    /**
     * Renders the injected form params and returns the HTML code.
     * 
     * @param   bool    $load_assets    Whether to load the necessary assets.
     * 
     * @return  string
     */
    public function getHtml($load_assets = true)
    {
        if (!$this->params) {
            return '';
        }

        // build the HTML params string
        $html = '';

        // list of conditional field rules
        $js_conditional_fields = [];

        // scan all field params
        foreach ($this->params as $param_name => $param_config) {
            if (empty($param_name)) {
                continue;
            }

            $labelparts = explode('//', (isset($param_config['label']) ? $param_config['label'] : ''));
            $label = $labelparts[0];
            $labelhelp = isset($labelparts[1]) ? $labelparts[1] : '';
            if (!empty($param_config['help'])) {
                $labelhelp = $param_config['help'];
            }

            $nested_style   = (isset($param_config['nested']) && $param_config['nested']);
            $hidden_wrapper = $param_config['type'] === 'hidden';
            if (!empty($param_config['conditional'])) {
                /**
                 * The conditional property can specify the value to check from the parent field
                 * i.e. "test_mode:1" means that the value should be equal to 1. Alternative,
                 * "test_mode!:1" means that the value should be different than 1.
                 * 
                 * @since   1.18.2 (J) - 1.8.2 (WP)
                 */
                $check_cond_field = $param_config['conditional'];
                $check_cond_oper  = null;
                $check_cond_value = null;
                if (preg_match('/^([a-z0-9_\-]+)(!?:)(.*?)$/i', (string) $check_cond_field, $cond_matches)) {
                    // conditional instruction detected
                    $check_cond_field = $cond_matches[1];
                    $check_cond_oper  = $cond_matches[2];
                    $check_cond_value = $cond_matches[3];
                }

                if (isset($this->params[$check_cond_field])) {
                    // get current value of the conditional parent field
                    $check_cond = $this->params[$check_cond_field]['default'] ?? null;
                    $check_cond = $this->settings[$check_cond_field] ?? $check_cond;
                    if (!is_null($check_cond)) {
                        // legacy syntax "conditional" => "test_mode"
                        if (!$check_cond_oper && (!$check_cond || !strcasecmp((string) $check_cond, 'off'))) {
                            // hide current field because the field to who this is dependant is "off" or disabled (i.e. 0)
                            $hidden_wrapper = true;
                        }
                        // conditional (equal) syntax "conditional" => "test_mode:1"
                        if ($check_cond_oper === ':' && $check_cond != $check_cond_value) {
                            // equal condition not met, hide the field
                            $hidden_wrapper = true;
                        }
                        // conditional (different) syntax "conditional" => "test_mode!:0"
                        if ($check_cond_oper === '!:' && $check_cond == $check_cond_value) {
                            // different condition not met, hide the field
                            $hidden_wrapper = true;
                        }
                    }
                }

                if (!is_null($check_cond_value)) {
                    // the field is dependant on another through a syntax, memorize the condition for JS
                    $js_conditional_fields[$check_cond_field][] = [
                        'field'    => $param_name,
                        'oper'     => $check_cond_oper,
                        'value'    => $check_cond_value,
                        'multiple' => !empty($param_config['multiple']),
                        'custom'   => $param_config['type'] === 'custom',
                    ];
                }
            }

            $html .= '<div class="vrc-param-container' . (in_array($param_config['type'], ['textarea', 'visual_html']) ? ' vrc-param-container-full' : '') . ($nested_style ? ' vrc-param-nested' : '') . '"' . ($hidden_wrapper ? ' style="display: none;"' : '') . '>';
            if (strlen($label) && (!isset($param_config['hidden']) || $param_config['hidden'] != true)) {
                $html .= '<div class="vrc-param-label">' . $label . '</div>';
            }
            $html .= '<div class="vrc-param-setting"' . ($param_config['type'] === 'custom' ? ' data-custom="' . $this->inputName . '[' . $param_name . ']' . '"' : '') . '>';

            // render field
            $html .= $this->getField($param_name, $param_config);

            // check for assets to be loaded, only once to obtain individual setups
            if ($load_assets) {
                if ((VRCPlatformDetection::isWordPress() && wp_doing_ajax()) || (!VRCPlatformDetection::isWordPress() && !strcasecmp((string) JFactory::getApplication()->input->server->get('HTTP_X_REQUESTED_WITH', ''), 'xmlhttprequest'))) {
                    // concatenate script(s) to HTML string when doing an AJAX request
                    $html .= "\n" . '<script>' . implode("\n", $this->buildScriptAssets($load_once = true)) . '</script>';
                } else {
                    // add script declaration(s) to document
                    $this->loadAssets($load_once = true);
                }
            }

            if ($labelhelp) {
                $html .= '<span class="vrc-param-setting-comment">' . $labelhelp . '</span>';
            }

            $html .= '</div>';
            $html .= '</div>';
        }

        if ($js_conditional_fields) {
            // build the JS script for handling contional field changes
            $js_conditional_fields_json = json_encode($js_conditional_fields);
            $base_input_name = $this->inputName;
            $html .= 
<<<HTML
<script>
    VRCCore.DOMLoaded(() => {
        let js_conditional_fields = $js_conditional_fields_json;
        let base_input_name = "$base_input_name";

        // scan all parent fields
        Object.keys(js_conditional_fields).forEach((field_name) => {
            let parent_fields = Array.from(document.querySelectorAll('[name="' + base_input_name + '[' + field_name + ']"]')).filter((field_input) => {
                // get only valid input fields
                return (field_input.matches('input') || field_input.matches('select') || field_input.matches('textarea')) && !field_input.matches('input[type="hidden"]');
            });

            let parent_field = parent_fields[0] || null;
            if (!parent_field) {
                // invalid input field selected
                return;
            }

            if (!Array.isArray(js_conditional_fields[field_name])) {
                // invalid parent conditions
                return;
            }

            // add change event listener
            parent_field.addEventListener('change', (e) => {
                // get the parent field current value
                let parent_value = e.target.value;
                if (e.target.matches('input[type="checkbox"]')) {
                    // checkbox fields should rely on their checked status
                    parent_value = e.target.checked ? '1' : '0';
                }

                // scan all dependant fields
                js_conditional_fields[field_name].forEach((condition) => {
                    let field_selector = condition?.multiple ? '[name="' + base_input_name + '[' + condition.field + '][]"]' : '[name="' + base_input_name + '[' + condition.field + ']"]';
                    if (condition.custom === true) {
                        field_selector = '[data-custom="' + base_input_name + '[' + condition.field + ']"]';
                    }
                    let cond_fields = Array.from(document.querySelectorAll(field_selector)).filter((input_field) => {
                        // get only valid input fields or custom containers
                        if (input_field.matches('input[type="hidden"][data-type="file_upload"]')) {
                            return true;
                        }
                        if (condition.custom === true && input_field.matches('.vrc-param-setting[data-custom]')) {
                            return true;
                        }
                        return (input_field.matches('input') || input_field.matches('select') || input_field.matches('textarea')) && !input_field.matches('input[type="hidden"]');
                    });

                    let cond_field = cond_fields[0] || null;
                    if (!cond_field) {
                        // invalid conditional field selected
                        return;
                    }

                    // find the conditional field container
                    let cond_field_target = cond_field.closest('.vrc-param-container');
                    if (!cond_field_target) {
                        // conditional field container not found
                        return;
                    }

                    // validate condition syntax
                    if ((condition.oper == ':' && parent_value != condition.value) || (condition.oper == '!:' && parent_value == condition.value)) {
                        // hide conditional field not matching the condition syntax
                        cond_field_target.style.display = 'none';
                    } else {
                        // show conditional field
                        cond_field_target.style.display = '';
                    }
                });
            });
        });

    });
</script>
HTML;
        }

        // JS helper functions
        $html .= $this->getScripts();

        return $html;
    }

    /**
     * Builds the requested script assets, if any.
     * 
     * @param   bool    $load_once  True to unset the assets after loading.
     * 
     * @return  array
     * 
     * @since   1.18.0 (J) - 1.8.0 (WP)
     */
    public function buildScriptAssets($load_once = false)
    {
        $scripts = [];

        foreach ($this->assets as $asset_type => $asset_elements) {
            if ($asset_type === 'select2') {
                // build list of selectors
                $ids_list = implode(', ', array_map(function($el) {
                    return "#{$el}";
                }, $asset_elements));

                // check for asset options
                $asset_options = $this->assets['select2_options'] ?? null;
                $asset_options_str = $asset_options ? json_encode($asset_options) : '';

                // always attempt to load assets
                VikRentCar::getVrcApplication()->loadSelect2();

                // build and push script
                $scripts[] =
<<<JAVASCRIPT
jQuery(function() {
    jQuery('$ids_list').select2($asset_options_str);
});
JAVASCRIPT;
            }

            if ($load_once) {
                unset($this->assets[$asset_type]);
            }
        }

        return $scripts;
    }

    /**
     * Loads the requested assets, if any.
     * 
     * @param   bool    $load_once  True to unset the assets after loading.
     * 
     * @return  void
     */
    public function loadAssets($load_once = false)
    {
        $doc = JFactory::getDocument();

        foreach ($this->buildScriptAssets($load_once) as $script) {
            $doc->addScriptDeclaration($script);
        }
    }

    /**
     * Gets the necessary script tags.
     * 
     * @return  string
     */
    public function getScripts()
    {
        $html = '';

        if (in_array('password', $this->scripts)) {
            // toggle the password fields
            $html .= "\n" . '<script>' . "\n";
            $html .= 'function vrcParamTogglePwd(elem) {' . "\n";
            $html .= '  var btn = jQuery(elem), inp = btn.parent().find("input").first();' . "\n";
            $html .= '  if (!inp || !inp.length) {return false;}' . "\n";
            $html .= '  var inp_type = inp.attr("type");' . "\n";
            $html .= '  inp.attr("type", (inp_type == "password" ? "text" : "password"));' . "\n";
            $html .= '}' . "\n";
            $html .= "\n" . '</script>' . "\n";
        }

        return $html;
    }

    /**
     * Renders the given param name according to config.
     * Eventually populates the assets and scripts to be loaded.
     * 
     * @param   string  $param_name     The param name.
     * @param   array   $param_config   The param configuration.
     * 
     * @return  string
     */
    public function getField($param_name, $param_config)
    {
        $html = '';

        $inp_attr = '';
        if (isset($param_config['attributes']) && is_array($param_config['attributes'])) {
            foreach ($param_config['attributes'] as $inpk => $inpv) {
                $inp_attr .= $inpk . '="' . $inpv . '" ';
            }
            $inp_attr = ' ' . rtrim($inp_attr);
        }

        $default_paramv = $param_config['default'] ?? null;

        switch ($param_config['type']) {
            case 'custom':
                $html .= $param_config['html'];
                break;
            case 'select':
                $options    = isset($param_config['options']) && is_array($param_config['options']) ? $param_config['options'] : [];
                $is_assoc   = (array_keys($options) !== range(0, count($options) - 1));
                $element_id = 'vik-select-' . static::$instance_counter . '-' . preg_replace("/[^A-Z0-9]+/i", '', $param_name);
                $set_attr   = true;
                if (isset($param_config['attributes']) && is_array($param_config['attributes']) && isset($param_config['attributes']['id'])) {
                    $element_id = $param_config['attributes']['id'];
                    $set_attr   = false;
                }
                if (isset($param_config['assets']) && $param_config['assets']) {
                    if (!isset($this->assets['select2'])) {
                        $this->assets['select2'] = [];
                    }
                    $this->assets['select2'][] = $element_id;
                    $this->assets['select2_options'] = $param_config['asset_options'] ?? null;
                }
                if (isset($param_config['multiple']) && $param_config['multiple']) {
                    $html .= '<select name="' . $this->inputName . '[' . $param_name . '][]" multiple="multiple"' . $inp_attr . ($set_attr ? ' id="' . $element_id . '"' : '') . '>' . "\n";
                } else {
                    $html .= '<select name="' . $this->inputName . '[' . $param_name . ']"' . $inp_attr . ($set_attr ? ' id="' . $element_id . '"' : '') . '>' . "\n";
                }
                foreach ($options as $optind => $optval) {
                    // support nested array values for the option-group tags
                    $group = null;
                    $sel_opts = [$optind => $optval];
                    if (is_array($optval)) {
                        $group = $optind;
                        $sel_opts = $optval;
                    }
                    if ($group) {
                        $html .= '<optgroup label="' . JHtml::fetch('esc_attr', JText::translate($group)) . '">' . "\n";
                    }
                    foreach ($sel_opts as $optkey => $poption) {
                        $checkval = $is_assoc ? $optkey : $poption;
                        $selected = false;
                        if (isset($this->settings[$param_name])) {
                            if (is_array($this->settings[$param_name])) {
                                $selected = in_array($checkval, $this->settings[$param_name]);
                            } else {
                                $selected = ($checkval == $this->settings[$param_name]);
                            }
                        } elseif (isset($default_paramv)) {
                            if (is_array($default_paramv)) {
                                $selected = in_array($checkval, $default_paramv);
                            } else {
                                $selected = ($checkval == $default_paramv);
                            }
                        }
                        $html .= '<option value="' . ($is_assoc ? $optkey : $poption) . '"'.($selected ? ' selected="selected"' : '').'>'.$poption.'</option>' . "\n";
                    }
                    if ($group) {
                        $html .= '</optgroup>' . "\n";
                    }
                }
                $html .= '</select>' . "\n";
                break;
            case 'tags':
                // build attributes list
                $element_id = 'vik-select-' . static::$instance_counter . '-' . preg_replace("/[^A-Z0-9]+/i", '', $param_name);
                $elements_attr = [
                    'name' => $this->inputName . '[' . $param_name . ']',
                ];
                if ($param_config['multiple'] ?? null) {
                    $elements_attr['multiple'] = 'multiple';
                    $elements_attr['name'] .= '[]';
                }
                $custom_attr = (array) ($param_config['attributes'] ?? []);
                unset($custom_attr['id'], $custom_attr['name']);
                $elements_attr = array_merge($elements_attr, $custom_attr);

                $wrapped = false;
                $style_selection = (bool) ($param_config['style_selection'] ?? null);
                if ($param_config['inline'] ?? true) {
                    // wrap the select within an additional div
                    $html .= '<div class="' . (($param_config['multiple'] ?? null) ? 'vrc-multiselect-inline-elems-wrap' : 'vrc-singleselect-inline-elems-wrap') . '">';
                    $wrapped = true;
                    $style_selection = (bool) ($param_config['multiple'] ?? null);
                } elseif ($param_config['wrapdivcls'] ?? null) {
                    // wrap the select within a custom div
                    $html .= '<div class="' . $param_config['wrapdivcls'] . '">';
                    $wrapped = true;
                }

                // obtain the necessary HTML code for rendering
                $html .= VikRentCar::getVrcApplication()->renderTagsDropDown([
                    'id'                  => $element_id,
                    'placeholder'         => ($param_config['asset_options']['placeholder'] ?? null),
                    'allow_clear'         => ($param_config['asset_options']['allowClear'] ?? $param_config['asset_options']['allow_clear'] ?? null),
                    'attributes'          => $elements_attr,
                    'selected_value'      => (is_scalar($this->settings[$param_name] ?? null) ? $this->settings[$param_name] : (is_scalar($default_paramv ?? null) ? $default_paramv : null)),
                    'selected_values'     => (is_array($this->settings[$param_name] ?? null) ? $this->settings[$param_name] : (is_array($default_paramv ?? null) ? $default_paramv : null)),
                    'style_selection'     => $style_selection,
                ], (array) ($param_config['tags'] ?? []), (array) ($param_config['groups'] ?? []));

                if ($wrapped) {
                    // close the select div wrapper
                    $html .= '</div>';
                }
                break;
            case 'datetime':
                // build attributes list
                $element_id = 'vik-dtp-' . static::$instance_counter . '-' . preg_replace("/[^A-Z0-9]+/i", '', $param_name);
                $elements_attr = [
                    'name'  => $this->inputName . '[' . $param_name . ']',
                    'value' => $this->settings[$param_name] ?? $default_paramv ?: '',
                ];
                $custom_attr = (array) ($param_config['attributes'] ?? []);
                unset($custom_attr['id'], $custom_attr['name'], $custom_attr['value']);
                $elements_attr = array_merge($elements_attr, $custom_attr);

                // obtain the necessary HTML code for rendering
                $html .= VikRentCar::getVrcApplication()->renderDateTimePicker([
                    'id'         => $element_id,
                    'attributes' => $elements_attr,
                ]);
                break;
            case 'time':
                // build attributes list
                $element_id = 'vik-tp-' . static::$instance_counter . '-' . preg_replace("/[^A-Z0-9]+/i", '', $param_name);
                $elements_attr = [
                    'name'  => $this->inputName . '[' . $param_name . ']',
                    'value' => $this->settings[$param_name] ?? $default_paramv ?: '',
                ];
                $custom_attr = (array) ($param_config['attributes'] ?? []);
                unset($custom_attr['id'], $custom_attr['name'], $custom_attr['value']);
                $elements_attr = array_merge($elements_attr, $custom_attr);

                // obtain the necessary HTML code for rendering
                $html .= VikRentCar::getVrcApplication()->renderTimePicker([
                    'id'         => $element_id,
                    'attributes' => $elements_attr,
                ]);
                break;
            case 'password':
                $html .= '<div class="btn-wrapper input-append">';
                $html .= '<input type="password" name="' . $this->inputName . '[' . $param_name . ']" value="'.(isset($this->settings[$param_name]) ? JHtml::fetch('esc_attr', $this->settings[$param_name]) : JHtml::fetch('esc_attr', $default_paramv)).'" autocomplete="new-password" size="20"' . $inp_attr . '/>';
                $html .= '<button type="button" class="btn btn-primary" onclick="vrcParamTogglePwd(this);"><i class="' . VikRentCarIcons::i('eye') . '"></i></button>';
                $html .= '</div>';
                // set flag for JS helper
                $this->scripts[] = $param_config['type'];
                break;
            case 'number':
                $number_attr = [];
                if (isset($param_config['min'])) {
                    $number_attr[] = 'min="' . JHtml::fetch('esc_attr', $param_config['min']) . '"';
                }
                if (isset($param_config['max'])) {
                    $number_attr[] = 'max="' . JHtml::fetch('esc_attr', $param_config['max']) . '"';
                }
                if (isset($param_config['step'])) {
                    $number_attr[] = 'step="' . JHtml::fetch('esc_attr', $param_config['step']) . '"';
                }
                $html .= '<input type="number" name="' . $this->inputName . '[' . $param_name . ']" value="'.(isset($this->settings[$param_name]) ? JHtml::fetch('esc_attr', $this->settings[$param_name]) : JHtml::fetch('esc_attr', $default_paramv)).'" ' . implode(' ', $number_attr) . $inp_attr . '/>';
                break;
            case 'textarea':
                $html .= '<textarea name="' . $this->inputName . '[' . $param_name . ']"' . $inp_attr . '>'.(isset($this->settings[$param_name]) ? JHtml::fetch('esc_textarea', $this->settings[$param_name]) : JHtml::fetch('esc_textarea', $default_paramv)).'</textarea>';
                break;
            case 'visual_html':
                $tarea_cont = isset($this->settings[$param_name]) ? JHtml::fetch('esc_textarea', $this->settings[$param_name]) : JHtml::fetch('esc_textarea', $default_paramv);
                $tarea_attr = isset($param_config['attributes']) && is_array($param_config['attributes']) ? $param_config['attributes'] : [];
                $editor_opts = isset($param_config['editor_opts']) && is_array($param_config['editor_opts']) ? $param_config['editor_opts'] : [];
                $editor_btns = isset($param_config['editor_btns']) && is_array($param_config['editor_btns']) ? $param_config['editor_btns'] : [];
                $html .= VikRentCar::getVrcApplication()->renderVisualEditor($this->inputName . '[' . $param_name . ']', $tarea_cont, $tarea_attr, $editor_opts, $editor_btns);
                break;
            case 'codemirror':
                $editor = JEditor::getInstance('codemirror');
                $e_options = isset($param_config['options']) && is_array($param_config['options']) ? $param_config['options'] : [];
                $e_name = $this->inputName . '[' . $param_name . ']';
                $e_value = isset($this->settings[$param_name]) ? $this->settings[$param_name] : $default_paramv;
                $e_width = isset($e_options['width']) ? $e_options['width'] : '100%';
                $e_height = isset($e_options['height']) ? $e_options['height'] : 300;
                $e_col = isset($e_options['col']) ? $e_options['col'] : 70;
                $e_row = isset($e_options['row']) ? $e_options['row'] : 20;
                $e_buttons = isset($e_options['buttons']) ? (bool)$e_options['buttons'] : true;
                $e_id = isset($e_options['id']) ? $e_options['id'] : $this->inputName . '_' . $param_name;
                $e_params = isset($e_options['params']) && is_array($e_options['params']) ? $e_options['params'] : [];
                if (interface_exists('Throwable')) {
                    /**
                     * With PHP >= 7 supporting throwable exceptions for Fatal Errors
                     * we try to avoid issues with third party plugins that make use
                     * of the WP native function get_current_screen().
                     * 
                     * @wponly
                     */
                    try {
                        $html .= $editor->display($e_name, $e_value, $e_width, $e_height, $e_col, $e_row, $e_buttons, $e_id, $e_asset = null, $e_autor = null, $e_params);
                    } catch (Throwable $t) {
                        $html .= $t->getMessage() . ' in ' . $t->getFile() . ':' . $t->getLine() . '<br/>';
                        $html .= '<textarea name="' . $this->inputName . '[' . $param_name . ']"' . $inp_attr . '>' . (isset($this->settings[$param_name]) ? JHtml::fetch('esc_textarea', $this->settings[$param_name]) : JHtml::fetch('esc_textarea', $default_paramv)) . '</textarea>';
                    }
                } else {
                    $html .= $editor->display($e_name, $e_value, $e_width, $e_height, $e_col, $e_row, $e_buttons, $e_id, $e_asset = null, $e_autor = null, $e_params);
                }
                break;
            case 'hidden':
                $html .= '<input type="hidden" name="' . $this->inputName . '[' . $param_name . ']" value="'.(isset($this->settings[$param_name]) ? JHtml::fetch('esc_attr', $this->settings[$param_name]) : JHtml::fetch('esc_attr', $default_paramv)).'"' . $inp_attr . '/>';
                break;
            case 'checkbox':
                // always display a hidden input value turned off before the actual checkbox to support the "off" (0) status
                $html .= '<input type="hidden" name="' . $this->inputName . '[' . $param_name . ']" value="0" />';
                $html .= VikRentCar::getVrcApplication()->printYesNoButtons($this->inputName . '['.$param_name.']', JText::translate('VRYES'), JText::translate('VRNO'), (isset($this->settings[$param_name]) ? (int)$this->settings[$param_name] : (int)$default_paramv), 1, 0);
                break;
            case 'calendar':
                $e_options = isset($param_config['options']) && is_array($param_config['options']) ? $param_config['options'] : [];
                $e_id = isset($e_options['id']) ? $e_options['id'] : $this->inputName . '_' . $param_name;
                $html .= VikRentCar::getVrcApplication()->getCalendar($this->settings[$param_name] ?? $default_paramv, $this->inputName . '['.$param_name.']', $e_id, $e_options['df'] ?? null, $e_options['attributes'] ?? []);
                break;
            case 'file_upload':
                /**
                 * File upload (AJAX) field, for single or multiple files uploading.
                 * 
                 * @since   1.15.9 (J) - 1.4.6 (WP)
                 */
                $element_id = 'vik-fileupload-' . static::$instance_counter . '-' . preg_replace("/[^A-Z0-9]+/i", '', $param_name);
                $element_nm = $this->inputName . '[' . $param_name . ']';
                $multiple   = '';
                if ($param_config['multiple'] ?? null) {
                    $multiple = 'multiple';
                    $element_nm .= '[]';
                }

                // site root URI
                $site_uri = JUri::root();

                // CSRF token for safe AJAX requests
                $csrf = addslashes(JSession::getFormToken());

                // default file icon class
                $file_icon_class = VikRentCarIcons::i('file');

                // JSON upload options
                $upload_options = [
                    'element_id' => $element_id,
                    'csrf_token' => $csrf,
                    'field_name' => 'vrc_files',
                    'param_name' => $element_nm,
                    'upload_url' => VikRentCar::ajaxUrl('index.php?option=com_vikrentcar&task=service.upload'),
                    'allowed_types'  => (string) ($param_config['allowed_types'] ?? ''),
                    'safe_file_name' => (int) ($param_config['safe_file_name'] ?? 0),
                    'return_type'    => (string) ($param_config['return_type'] ?? 'path'),
                    'file_icon_class' => $file_icon_class,
                    'loading_icon_class' => VikRentCarIcons::i('circle-notch', 'fa-spin fa-fw'),
                ];
                $json_upload_options = json_encode($upload_options);

                // upload or drag & drop text
                $help_text = sprintf('<a href="JavaScript: void(0);">%s</a> %s', JText::translate('VRCMANUALUPLOAD'), JText::translate('VRCDROPFILES'));

                // uploaded files
                $uploaded_files = array_values(array_filter((array) ($this->settings[$param_name] ?? null)));
                $uploaded_html = '';
                foreach ($uploaded_files as $uploaded_file) {
                    if (strpos($uploaded_file, VRC_ADMIN_PATH) !== false && !is_file($uploaded_file)) {
                        // file value is an internal path, but it no longer exists
                        continue;
                    }
                    $uploaded_file_val  = htmlspecialchars((string) $uploaded_file, ENT_QUOTES, 'UTF-8');
                    $uploaded_file_name = basename((string) $uploaded_file);
                    $uploaded_file_cont = $uploaded_file_name;
                    if (strpos($uploaded_file, $site_uri) !== false) {
                        // make it a link
                        $uploaded_file_cont = '<a href="' . $uploaded_file . '" target="_blank">' . $uploaded_file_name . '</a>';
                    }
                    // render current file
                    $uploaded_html .= <<<HTML
<div class="file-elem">
    <div class="file-elem-inner">
        <div class="file-summary">
            <i class="{$file_icon_class}"></i>
            <div class="filename">{$uploaded_file_cont}</div>
            <input type="hidden" name="{$element_nm}" value="{$uploaded_file_val}" data-type="file_upload" />
        </div>
    </div>
</div>
HTML;
                }

                if (!$uploaded_files) {
                    // display an empty input hidden element to let any conditional rule work
                    $uploaded_html = <<<HTML
<input type="hidden" name="{$element_nm}" value="" data-type="file_upload" data-empty="1" />
HTML;
                }

                // visible element
                $html .= <<<HTML
<div class="vrc-param-file-upload-wrap vrc-dropfiles-target">
    <div class="vrc-uploaded-files">{$uploaded_html}</div>
    <div class="vrc-param-file-upload-loading"></div>
    <div class="lead">{$help_text}</div>
    <input type="file" id="{$element_id}" data-upload="{$multiple}" hidden {$multiple}/>
</div>
<script>
    function vrcParamFieldRenderUploads(result, options) {
        if (!options?.inputElement) {
            throw new Error('Missing target');
        }

        if (!result?.processed) {
            throw new Error('No files were processed');
        }

        if (!result?.paths || !result.paths.length) {
            alert('No valid files were uploaded');
            return;
        }

        // define the default file-uploaded icon element class list
        let fileIconClassList = [];
        if (options?.file_icon_class) {
            fileIconClassList = options.file_icon_class.split(' ');
        }

        // target the current list of files uploaded and make it empty
        const filesPool = options.inputElement.closest('.vrc-param-file-upload-wrap').querySelector('.vrc-uploaded-files');
        filesPool.innerHTML = '';

        // iterate over each file uploaded
        result.fileNames.forEach((name, index) => {
            // build uploaded file nodes
            let fileNode = document.createElement('div');
            fileNode.classList.add('file-elem');
            let fileInner = document.createElement('div');
            fileInner.classList.add('file-elem-inner');
            let fileSummary = document.createElement('div');
            fileSummary.classList.add('file-summary');
            let fileIcon = document.createElement('i');
            if (fileIconClassList.length) {
                fileIcon.classList.add(...fileIconClassList);
            }
            let fileName = document.createElement('div');
            fileName.classList.add('filename');
            fileName.innerText = name;
            let fileInput = document.createElement('input');
            fileInput.setAttribute('type', 'hidden');
            fileInput.setAttribute('name', options?.param_name);
            if (options?.return_type == 'url') {
                fileInput.value = result.urls[index] || name;
                // make the file name element a link
                fileName.innerText = '';
                let fileLink = document.createElement('a');
                fileLink.setAttribute('href', fileInput.value);
                fileLink.setAttribute('target', '_blank');
                fileLink.innerText = name;
                fileName.append(fileLink);
            } else if (options?.return_type == 'name') {
                fileInput.value = name;
            } else {
                fileInput.value = result.paths[index] || name;
            }

            // append nodes to files pool
            fileSummary.append(fileIcon, fileName, fileInput);
            fileInner.append(fileSummary);
            fileNode.append(fileInner);
            filesPool.append(fileNode);
        });
    }

    async function vrcParamFieldUploadFiles(files, options) {
        const fieldBaseName = options?.field_name;
        const formData = new FormData();
        for (let i = 0; i < files.length; i++) {
            formData.append(fieldBaseName + '[]', files[i]);
        }

        if (options?.allowed_types) {
            // comma separated string of allowed file extension types
            formData.append('allowed_types', options.allowed_types);
        }

        if (options?.safe_file_name) {
            // whether to keep the original file name or randomize it
            formData.append('safe_file_name', options.safe_file_name);
        }

        // define the default upload-loading icon element class list
        let loadingIconClassList = [];
        let loadingElement = null;
        if (options?.loading_icon_class) {
            loadingIconClassList = options.loading_icon_class.split(' ');
        }

        if (loadingIconClassList.length && options?.inputElement) {
            // build loading icon element
            loadingElement = document.createElement('i');
            loadingElement.classList.add(...loadingIconClassList);
            // append loading element
            options
                .inputElement
                .closest('.vrc-param-file-upload-wrap')
                .querySelector('.vrc-param-file-upload-loading')
                .append(loadingElement);
        }

        try {
            const response = await fetch(options?.upload_url, {
                method: 'POST',
                headers: {
                    'X-CSRF-Token': options?.csrf_token,
                },
                body: formData,
            });

            const result = await response.json().catch(() => null);

            if (response.ok) {
                // render files uploaded
                vrcParamFieldRenderUploads(result, options);
            } else {
                alert('Upload failed: ' + response.statusText);
            }
        } catch (error) {
            console.error('Upload error:', error);
            alert('An error occurred during upload.');
        }

        if (options?.inputElement) {
            // reset file input element value to allow additional uploads
            options.inputElement.value = '';
        }

        if (loadingElement) {
            // remove loading animation
            loadingElement.remove();
        }
    }

    function vrcParamFieldUploadSetup(options) {
        // target elements
        const fileInput = document.getElementById(options?.element_id);
        const dropTarget = fileInput.closest('.vrc-param-file-upload-wrap');

        // open file dialog by simulating the click on hidden file input
        dropTarget.addEventListener('click', () => fileInput.click());

        // drop target drag and drop events
        dropTarget.addEventListener('dragover', e => {
            e.preventDefault();
            dropTarget.classList.add('drag-over', 'drag-enter');
        });
        dropTarget.addEventListener('dragleave', () => {
            dropTarget.classList.remove('drag-over', 'drag-enter');
        });
        dropTarget.addEventListener('drop', async e => {
            e.preventDefault();
            dropTarget.classList.remove('drag-over', 'drag-enter');
            const files = e.dataTransfer.files;
            if (files.length) {
                await vrcParamFieldUploadFiles(files, Object.assign({}, options, {inputElement: fileInput}));
            }
        });

        // input file element change event
        fileInput.addEventListener('change', async e => {
            if (e.target.files.length) {
                await vrcParamFieldUploadFiles(e.target.files, Object.assign({}, options, {inputElement: fileInput}));
            }
        });
    }

    // configure field
    vrcParamFieldUploadSetup({$json_upload_options});
</script>
HTML;
                break;
            default:
                $html .= '<input type="text" name="' . $this->inputName . '[' . $param_name . ']" value="'.(isset($this->settings[$param_name]) ? JHtml::fetch('esc_attr', $this->settings[$param_name]) : JHtml::fetch('esc_attr', $default_paramv)).'" size="20"' . $inp_attr . '/>';
                break;
        }

        return $html;
    }
}
