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<?php

namespace WPGMZA;

class Categories
{
    public static function createMarkersHasCategoriesTable()
    {
        global $wpdb;
        global $WPGMZA_TABLE_NAME_MARKERS_HAS_CATEGORIES;
        
        $stmt = $wpdb->prepare("SHOW TABLES LIKE %s", array($WPGMZA_TABLE_NAME_MARKERS_HAS_CATEGORIES));
        $table = $wpdb->get_var($stmt);
        
        if($table)
            return;
        
        $wpdb->query("CREATE TABLE `$WPGMZA_TABLE_NAME_MARKERS_HAS_CATEGORIES` (
                marker_id int(11) NOT NULL,
                category_id int(11) NOT NULL,
                PRIMARY KEY  (marker_id, category_id)
            ) ENGINE=InnoDB DEFAULT CHARSET=utf8;
        ");
    }
    
    public static function migrateMarkerCategoryField()
    {
        global $wpdb;
        global $wpgmza_tblname;
        
        Categories::createMarkersHasCategoriesTable();
        
        $markers = $wpdb->get_results("SELECT id, category FROM $wpgmza_tblname");
        
        foreach($markers as $marker)
        {
            if(empty($marker->category))
                continue;
            
            $categories = explode(',', $marker->category);
            
            foreach($categories as $category_id)
                $wpdb->query("INSERT INTO $WPGMZA_TABLE_NAME_MARKERS_HAS_CATEGORIES (marker_id, category_id) VALUES ({$marker->id}, {$category_id})");
        }
    }
}