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<?php if (!defined('BASEPATH')) exit('No direct script access allowed');

/**
 * Inventory class
 */

class Inventory extends CI_Model
{
    public function insert($inventory_data)
    {
        return $this->db->insert('inventory', $inventory_data);
    }

    public function get_inventory_data_for_item($item_id, $location_id = FALSE)
    {
        $this->db->from('inventory');
        $this->db->where('trans_items', $item_id);
        if($location_id != FALSE)
        {
            $this->db->where('trans_location', $location_id);
        }
        $this->db->order_by('trans_date', 'desc');

        return $this->db->get();
    }

    public function reset_quantity($item_id)
    {
        $inventory_sums = $this->Inventory->get_inventory_sum($item_id);
        foreach($inventory_sums as $inventory_sum)
        {
            if ($inventory_sum['sum'] > 0)
            {
                return $this->Inventory->insert(array(
                    'trans_inventory' => -1 * $inventory_sum['sum'],
                    'trans_items' => $item_id,
                    'trans_location' => $inventory_sum['location_id'],
                    'trans_comment' => $this->lang->line('items_is_deleted'),
                    'trans_user' => $this->Employee->get_logged_in_employee_info()->person_id)
                );
            }
        }
        return TRUE;
    }

    public function get_inventory_sum($item_id)
    {
        $this->db->select('SUM(trans_inventory) AS sum, MAX(trans_location) AS location_id');
        $this->db->from('inventory');
        $this->db->where('trans_items', $item_id);
        $this->db->group_by('trans_location');

        return $this->db->get()->result_array();
    }
}
?>