<?php
// Own namespace
namespace Org\Mxchange\CoreFramework\Iterator;

// Import framework stuff
use Org\Mxchange\CoreFramework\Iterator\BaseIterator;
use Org\Mxchange\CoreFramework\Lists\Listable;
use Org\Mxchange\CoreFramework\Registry\Registerable;

// Import SPL stuff
use \Iterator;

/**
 * A Default iterator
 *
 * @author		Roland Haeder <webmaster@shipsimu.org>
 * @version		0.0.0
 * @copyright	Copyright (c) 2007, 2008 Roland Haeder, 2009 - 2023 Core Developer Team
 * @license		GNU GPL 3.0 or any newer version
 * @link		http://www.shipsimu.org
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
class DefaultIterator extends BaseIterator implements Iterator, Registerable {
	/**
	 * Key for the global list index
	 */
	private $indexKey = 0;

	/**
	 * Protected constructor
	 *
	 * @return	void
	 */
	private function __construct () {
		// Call parent constructor
		parent::__construct(__CLASS__);
	}

	/**
	 * Creates an instance of this class
	 *
	 * @param	$listInstance		A list of a Listable
	 * @return	$iteratorInstance	An instance a Iterator class
	 */
	public static final function createDefaultIterator (Listable $listInstance) {
		// Get new instance
		$iteratorInstance = new DefaultIterator();

		// Set the list
		$iteratorInstance->setListInstance($listInstance);

		// Return the prepared instance
		return $iteratorInstance;
	}

	/**
	 * Getter for current value from group or generic
	 *
	 * @return	$current	Current value in iteration
	 * @throws	IndexOutOfBoundsException	If $indexKey is out of bounds
	 */
	public function current () {
		// Default is null
		$current = NULL;

		// Is the entry valid?
		if (!$this->valid()) {
			// Throw an exception here
			throw new IndexOutOfBoundsException($this->key(), self::EXCEPTION_INDEX_OUT_OF_BOUNDS);
		}

		// Now get the entry
		$current = $this->getListInstance()->getEntryByIndex($this->key());

		// Return it
		return $current;
	}

	/**
	 * Getter for key from group or generic
	 *
	 * @return	$indexKey	Current key in iteration
	 */
	public function key () {
		return $this->indexKey;
	}

	/**
	 * Advances to the next entry
	 *
	 * @return	void
	 */
	public function next () {
		$this->indexKey++;
	}

	/**
	 * Rewinds to the beginning of the iteration
	 *
	 * @return	void
	 */
	public function rewind () {
		$this->indexKey = 0;
	}

	/**
	 * Checks whether the current entry is valid (not at the end of the list)
	 *
	 * @return	$isValid	Whether the current entry is there
	 */
	public function valid () {
		// Check for total active peers and if we are not at the end
		$isValid = ($this->key() < $this->getListInstance()->count());

		// Return result
		return $isValid;
	}

}