Filtering helper useful for grids (or dynamic building of conditions)

Example.php

<?php

// $selection instanceof DibiFluent

$filter = FilterHelper::start($selection, $filter)
	->add('start_date')->setRule('[b.start_date] >= %d')
	->add('end_date')->setRule('[b.end_date] <= %d')
	->end();

FilterHelper.php

<?php

use DibiFluent;
use Nette\ArrayHash;


class FilterHelper
{

	/** @var DibiFluent */
	private $selection;

	/** @var ArrayHash */
	private $filter;

	/** @var string */
	private $currentColumn;


	public function __construct(DibiFluent $selection, array $filter)
	{
		$this->selection = $selection;
		$this->filter = ArrayHash::from($filter);
	}


	/**
	 * Sets column of new rule.
	 *
	 * @param  string
	 *
	 * @return FilterHelper provides a fluent interface
	 */
	public function add($column)
	{
		$this->currentColumn = $column;
		return $this;
	}


	/**
	 * Sets arguments of new rule.
	 *
	 * @param  mixed ...
	 *
	 * @return FilterHelper provides a fluent interface
	 */
	public function setRule()
	{
		if (isset($this->filter[$this->currentColumn])) {
			$args = func_get_args();
			$args[] = $this->filter[$this->currentColumn];
			call_user_func_array([$this->selection, 'where'], $args);
			unset($this->filter[$this->currentColumn]);
		}
		$this->currentColumn = NULL;
		return $this;
	}


	/**
	 * Adds rule %LIKE%
	 *
	 * @param  string
	 * @param  string|NULL
	 */
	public function like($value, $column = NULL)
	{
		return $this->setRule('%n LIKE %~like~', $column ? : $this->currentColumn);
	}


	/**
	 * @return array
	 */
	public function end()
	{
		return iterator_to_array($this->filter);
	}


	public static function start(DibiFluent $selection, array $filter)
	{
		return new self($selection, $filter);
	}

}