<?php
/* $Id$ */
namespace Mammut\DB\Sql\Expression;

(defined('MAMMUT') && (basename(__FILE__) != basename($_SERVER['PHP_SELF']))) or die('ACCESS DENIED');

use Mammut\DB\Sql\Dialect\iDialect;

/**
 * Compare operator
 *
 * @author Stefan Daurer <s.daurer@q-spot.org>
 * @package Mammut\DB\Sql
 */
class Compare extends \Mammut\StrictObject implements iExprBool {
	protected $left;
	protected $comparator;
	protected $right;

	public function __construct($left = null, $comparator = null, $right = null, $lefttype = iExprValue::TYPE_IDENTIFIER, $righttype = iExprValue::TYPE_VALUE) {
		if (!is_null($left))
			$this->setLeft($left, $lefttype);
		if (!is_null($right))
			$this->setRight($right, $righttype);
		if (!is_null($comparator))
			$this->setComparator($comparator);
	}

	public function setLeft($value, $type = iExprValue::TYPE_IDENTIFIER) {
		if($value instanceof Parameter)
			$type = iExprValue::TYPE_PARAMETER;
		$this->left = new Literal($value, $type);
		return $this;
	}

	public function getLeft() {
		return $this->left;
	}

	public function setRight($value, $type = iExprValue::TYPE_VALUE) {
		if($value instanceof Parameter)
			$type = iExprValue::TYPE_PARAMETER;
		$this->right = new Literal($value, $type);
		return $this;
	}

	public function getRight() {
		return $this->right;
	}

	public function setComparator($comparator) {
		$allowed = [self::OP_EQ,self::OP_NE,self::OP_GT,self::OP_GTE,self::OP_LT,self::OP_LTE];
		if(!in_array($comparator, $allowed))
			throw new \InvalidArgumentException('type:' . $comparator);
		$this->comparator = $comparator;
		return $this;
	}

	public function getComparator() {
		return $this->comparator;
	}
}