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<?php

namespace WPGMZA;

class CustomFieldFilterController
{
    public $params;
    
    public function __construct($params)
    {
        $this->params = $params;
    }
    
    protected function getFilterQueries()
    {
        $params = $this->params;
        
        $map_id = $params['map_id'];
        $queries = array();
        
        foreach($params['widgetData'] as $widgetData)
        {
            if(!is_array($widgetData))
                $widgetData = (array)$widgetData;
            
            $field_id = $widgetData['field_id'];
            $filter = apply_filters('wpgmza_get_custom_field_filter', $field_id, $map_id);
            
            if(!empty($widgetData['value']))
                $queries[] = $filter->getFilteringSQL($widgetData['value']);
        }
        
        return $queries;
    }
    
    /**
     * This function combines all the widget queries in a manner
     * that emulates the INTERSECT operator (Not available in MySQL)
     * @return string The query string
     */
    protected function getQuery()
    {
        global $wpdb;
        
        $queries = $this->getFilterQueries();
        
        if(empty($queries))
            return "SELECT id FROM {$wpdb->prefix}wpgmza WHERE map_id=" . (int)$this->params['map_id'];
        
        $numQueries = count($queries);
        
        foreach($queries as $key => $qstr)
            $queries[$key] = "($qstr)";
        
        $body = implode(' UNION ALL ', $queries);
        
        $query = "
            SELECT temp.id FROM (
                $body
            ) AS temp
            GROUP BY id HAVING COUNT(id) >= $numQueries
        ";
        
        return $query;
    }
    
    public function getFilteredMarkerIDs()
    {
        global $wpdb;
        
        $sql = $this->getQuery();
        $ids = $wpdb->get_col($sql);
        
        return $ids;
    }
}

add_filter('wpgmza_get_custom_field_filter_controlller', 'WPGMZA\\get_custom_field_filter_controller');

function get_custom_field_filter_controller($params)
{
    return new CustomFieldFilterController($params);
}

add_action('wp_ajax_nopriv_wpgmza_custom_field_filter_get_filtered_marker_ids', 'WPGMZA\\custom_field_filter_get_filtered_marker_ids');
add_action('wp_ajax_wpgmza_custom_field_filter_get_filtered_marker_ids', 'WPGMZA\\custom_field_filter_get_filtered_marker_ids');

function custom_field_filter_get_filtered_marker_ids() {
    
    $controller = apply_filters('wpgmza_get_custom_field_filter_controlller', $_POST);
    $filtered_marker_ids = $controller->getFilteredMarkerIDs();
    
    $result = (object)array(
        'marker_ids' => $filtered_marker_ids
    );
    
    wp_send_json($result);
    
    exit;
}