<?php
/**
 * @package     woobooking.Platform
 * @subpackage  Database
 *
 *  Copyright (C) 2005 - 2016 Open Source Matters, Inc. All rights reserved.
 * @license     GNU General Public License version 2 or later; see LICENSE
 */

namespace WpBookingHotel\Database\query;

use WpBookingHotel\Database\DatabaseQuery;

defined('_WPBOOKINGHOTEL_EXEC') or die;

/**
 * Query Building Class.
 *
 * @since  11.1
 */
class DatabaseQueryMysqli extends DatabaseQuery implements DatabaseQueryLimitable
{
    /**
     * @var    integer  The offset for the result set.
     * @since  12.1
     */
    protected $offset;
    /**
     * @var    integer  The limit for the result set.
     * @since  12.1
     */
    protected $limit;

    /**
     * Method to modify a query already in string format with the needed
     * additions to make the query limited to a particular number of
     * results, or start at a particular offset.
     *
     * @param string $query The query in string format
     * @param integer $limit The limit for the result set
     * @param integer $offset The offset for the result set
     *
     * @return string
     *
     * @since 12.1
     */
    public function processLimit($query, $limit, $offset = 0)
    {
        if ($limit > 0 && $offset > 0) {
            $query .= ' LIMIT ' . $offset . ', ' . $limit;
        } elseif ($limit > 0) {
            $query .= ' LIMIT ' . $limit;
        }
        return $query;
    }

    /**
     * Concatenates an array of column names or values.
     *
     * @param array $values An array of values to concatenate.
     * @param string $separator As separator to place between each value.
     *
     * @return  string  The concatenated values.
     *
     * @since   11.1
     */
    public function concatenate($values, $separator = null)
    {
        if ($separator) {
            $concat_string = 'CONCAT_WS(' . $this->quote($separator);
            foreach ($values as $value) {
                $concat_string .= ', ' . $value;
            }
            return $concat_string . ')';
        } else {
            return 'CONCAT(' . implode(',', $values) . ')';
        }
    }

    /**
     * Sets the offset and limit for the result set, if the database driver supports it.
     *
     * Usage:
     * $query->setLimit(100, 0); (retrieve 100 rows, starting at first record)
     * $query->setLimit(50, 50); (retrieve 50 rows, starting at 50th record)
     *
     * @param integer $limit The limit for the result set
     * @param integer $offset The offset for the result set
     *
     * @return  DatabaseQuery  Returns this object to allow chaining.
     *
     * @since   12.1
     */
    public function setLimit($limit = 0, $offset = 0)
    {
        $this->limit = (int)$limit;
        $this->offset = (int)$offset;
        return $this;
    }

    /**
     * Return correct regexp operator for mysqli.
     *
     * Ensure that the regexp operator is mysqli compatible.
     *
     * Usage:
     * $query->where('field ' . $query->regexp($search));
     *
     * @param string $value The regex pattern.
     *
     * @return  string  Returns the regex operator.
     *
     * @since   11.3
     */
    public function regexp($value)
    {
        return ' REGEXP ' . $value;
    }

    /**
     * Return correct rand() function for Mysql.
     *
     * Ensure that the rand() function is Mysql compatible.
     *
     * Usage:
     * $query->Rand();
     *
     * @return  string  The correct rand function.
     *
     * @since   3.5
     */
    public function Rand()
    {
        return ' RAND() ';
    }
}
