<?php
/* $Id$ */
namespace Mammut\DB\Model;

(defined('MAMMUT') && (basename(__FILE__) != basename($_SERVER['PHP_SELF']))) or die('ACCESS DENIED');

/**
 * Column reference model.
 *
 * Defines a reference to another table, realized as foreign keys in typical SQL databases. This can be used
 * to prevent invalid values in the data model.
 *
 * @author Stefan Daurer <s.daurer@q-spot.org>
 * @package Mammut\DB\Model
 */
class RefInfo extends \Mammut\StrictObject {
	
	/**
	 * Database behaviour "ON x NO ACTION"
	 */
	const ACT_PREVENT = 'prevent';
	/**
	 * Database behaviour "ON x CASCADE"
	 */
	const ACT_CASCADE = 'cascade';
	/**
	 * Database behaviour "ON x SET NULL"
	 */
	const ACT_NULL = 'null';
	/**
	 * Database behaviour "ON x SET DEFAULT"
	 */
	const ACT_DEFAULT = 'default';
	
	private $name = NULL;
	
	private $base;
	private $refTable;
	private $refColumns;
	
	private $update = self::ACT_PREVENT;
	private $delete = self::ACT_PREVENT;

	/**
	 * Create a new RefInfo model.
	 *
	 * @param mixed $base        	
	 * @param mixed $refTable        	
	 * @param mixed $refColumns        	
	 * @param string $update
	 *        	a ACT_* constant
	 * @param string $delete
	 *        	a ACT_* constant
	 * @param string $name
	 *        	the reference name
	 */
	public function __construct($base, $refTable, $refColumns, $update = self::ACT_PREVENT, $delete = self::ACT_PREVENT, $name = NULL) {
		$this->name = $name;
		
		$this->base = $base;
		$this->refTable = $refTable;
		$this->refColumns = $refColumns;
		$this->setUpdate($update);
		$this->setDelete($delete);
	}

	/**
	 * Checks if an action is a valid name
	 *
	 * @param string $a
	 *        	the action name which should be checked
	 * @return boolean true if known, false otherwise
	 */
	protected function validAction($a) {
		return in_array($a, [
				self::ACT_PREVENT,
				self::ACT_CASCADE,
				self::ACT_NULL,
				self::ACT_DEFAULT
		]);
	}

	public function getName() {
		return $this->name;
	}

	/**
	 *
	 * @return $this
	 */
	public function setName($name) {
		$this->name = $name;
		return $this;
	}

	public function getBase() {
		return $this->base;
	}

	/**
	 *
	 * @return $this
	 */
	public function setBase($base) {
		$this->base = $base;
		return $this;
	}

	public function getRefTable() {
		return $this->refTable;
	}

	/**
	 *
	 * @return $this
	 */
	public function setRefTable($refTable) {
		$this->refTable = $refTable;
		return $this;
	}

	public function getRefColumns() {
		return $this->refColumns;
	}

	/**
	 *
	 * @return $this
	 */
	public function setRefColumns($refColumns) {
		$this->refColumns = $refColumns;
		return $this;
	}

	public function getUpdate() {
		return $this->update;
	}

	/**
	 * Defines the action that should be taken if the parent row is updated
	 *
	 * @param string $update 
	 * 				one of the ACT_* constants
	 * @return $this
	 */
	public function setUpdate($update) {
		if(!$this->validAction($update))
			throw new \InvalidArgumentException($update);
		$this->update = $update;
		return $this;
	}

	public function getDelete() {
		return $this->delete;
	}

	/**
	 * Defines the action that should be taken if the parent row is deleted
	 *
	 * @param $delete string
	 *        	one of the ACT_* constants
	 * @return $this
	 */
	public function setDelete($delete) {
		if(!$this->validAction($delete))
			throw new \InvalidArgumentException($delete);
		$this->delete = $delete;
		return $this;
	}

}