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

// Import framework stuff
use Org\Mxchange\CoreFramework\Generic\FrameworkInterface;
use Org\Mxchange\CoreFramework\Generic\NullPointerException;
use Org\Mxchange\CoreFramework\Iterator\BaseIterator;
use Org\Mxchange\CoreFramework\Registry\Register;
use Org\Mxchange\CoreFramework\Registry\Registerable;
use Org\Mxchange\CoreFramework\Registry\Sub\SubRegistry;

// Import SPL stuff
use \LogicException;

/**
 * A Registry iterator
 *
 * @author		Roland Haeder <webmaster@ship-simu.org>
 * @version		0.0.0
 * @copyright	Copyright (c) 2007, 2008 Roland Haeder, 2009 - 2017 Core Developer Team
 * @license		GNU GPL 3.0 or any newer version
 * @link		http://www.ship-simu.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 RegistryIterator extends BaseIterator implements IteratableRegistry {
	/**
	 * All found registry keys
	 */
	private $registryKeys = array();

	/**
	 * Current array key
	 */
	private $key = NULL;

	/**
	 * Valid status (default: not valid)
	 */
	private $valid = FALSE;

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

	/**
	 * Creates an instance of this class
	 *
	 * @param	$registryInstance	An instance of a Register class
	 * @return	$iteratorInstance	An instance of a Iterator class
	 */
	public final static function createRegistryIterator (Register $registryInstance) {
		// Get new instance
		$iteratorInstance = new RegistryIterator();

		// Set registry here
		$iteratorInstance->setRegistryInstance($registryInstance);

		// Return the prepared instance
		return $iteratorInstance;
	}

	/**
	 * Initializes this iterator by scanning over the registry for all keys.
	 *
	 * @param	$callbackInstance	An instance of a FrameworkInterface class to call back (optional)
	 * @param	$criteriaKey		Criteria key (optional)
	 * @param	$criteriaMethod		Method to call back (optional)
	 * @return	void
	 * @throws	LogicException	If a registry entry does not implement Registerable
	 * @throws	NullPointerException	If criteriaKey or criteriaMethod is not set but a call-back instance is set
	 */
	public function initIterator (FrameworkInterface $callbackInstance = NULL, $criteriaKey = NULL, $criteriaMethod = NULL) {
		// Is the call-back instance set?
		if ($callbackInstance instanceof FrameworkInterface) {
			// Then also criteria key and method name must be given
			if (is_null($criteriaKey)) {
				// Throw NPE
				throw new NullPointerException($this, self::EXCEPTION_IS_NULL_POINTER);
			} elseif (is_null($criteriaMethod)) {
				// Throw NPE
				throw new NullPointerException($this, self::EXCEPTION_IS_NULL_POINTER);
			}

			// Set all
			$iteratorInstance->setCallbackInstance($callbackInstance);
			$iteratorInstance->setCriteriaKey($criteriaKey);
		} // END - if

		// Get generic registry entries from it
		$entries = $this->getRegistryInstance()->getGenericRegistry();

		// Init registry keys array
		$this->registryKeys['generic'] = array();

		// Anything in there?
		if (count($entries) > 0) {
			// Debugging:
			/* DEBUG-DIE: */ die(sprintf('[%s:%d]: entries=%s', __METHOD__, __LINE__, print_r($entries, TRUE)));
		} // END - if

		// Get instance registry entries from it
		$entries = $this->getRegistryInstance()->getInstanceRegistry();

		// Init registry keys array
		$this->registryKeys['instance'] = array();

		// Anything in there?
		if (count($entries) > 0) {
			// Then run over all
			foreach ($entries as $key => $entry) {
				// Debug message
				//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('REGISTRY-ITERATOR[instance]: key=%s,entry[]=%s', $key, gettype($entry)));

				// Is it 'socket_registry' ?
				if ($key == 'socket_registry') {
					// Skip this entry
					continue;
				} // END - if

				// Is it an instance of a sub-registry?
				if ($entry instanceof SubRegistry) {
					// Get iterator from this instance
					$iteratorInstance = $entry->getIterator();

					// Debugging:
					//* DEBUG-DIE: */ die(sprintf('[%s:%d]: key=%s,iteratorInstance=%s', __METHOD__, __LINE__, $key, print_r($iteratorInstance, TRUE)));

					// Get all keys
					$keys = $iteratorInstance->getRegistryKeys();

					// Should be there
					if (!isset($keys['instance'])) {
						// Should not happen
						throw new LogicException(sprintf('key=%s,keys[instance] is not set.', $key));
					} // END - if

					// Add all sub-registry keys to this registry keys array
					$this->registryKeys['instance'][$key] = $keys['instance'];

					// Debug message
					//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('REGISTRY-ITERATOR[instance]: key=%s,keys=%s', $key, print_r($this->registryKeys['instance'][$key], TRUE)));

					// Skip below code
					continue;
				} elseif (!($entry instanceof Registerable)) {
					// Not registerable?!
					throw new LogicException(sprintf('entry[]=%s does not implement Registerable.', gettype($entry)));
				} elseif (is_null($this->key)) {
					// Debug message
					//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('REGISTRY-ITERATOR[instance]: Setting key=%s ...', $key));

					// Init key/valid
					$this->key = $key;
					$this->valid = TRUE;
				}

				// Debugging:
				//* DEBUG-DIE: */ die(sprintf('[%s:%d]: key=%s,entry=%s', __METHOD__, __LINE__, $key, print_r($entry, TRUE)));
				//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('REGISTRY-ITERATOR[instance]: key=%s,entry[]=%s - Adding ...', $key, gettype($entry)));

				// Add key to array
				$this->registryKeys['instance'][$key] = array();
			} // END - foreach
		} // END - if
	}

	/**
	 * Getter for all registry keys (array)
	 *
	 * @return	$registryKeys	Registry keys
	 */
	public final function getRegistryKeys () {
		// Return it
		return $this->registryKeys;
	}

	/**
	 * Getter for current value from group or generic
	 *
	 * @return	$current	Current value in iteration
	 */
	public function current () {
		// Default is null
		$current = null;

		$this->partialStub('Please implement this method.');

		// Return it
		return $current;
	}

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

	/**
	 * Advances to the next entry
	 *
	 * @return	void
	 */
	public function next () {
		$this->partialStub('Please implement this method.');
	}

	/**
	 * Rewinds to the beginning of the iteration
	 *
	 * @return	void
	 */
	public function rewind () {
		// Debugging:
		/* DEBUG-DIE: */ die(sprintf('[%s:%d]: this->key(%d)[%s]=%s,this->valid=%d,this->registryKeys=%s', __METHOD__, __LINE__, strlen($this->key()), gettype($this->key()), $this->key(), intval($this->valid()), print_r($this->registryKeys, TRUE)));
	}

	/**
	 * Checks wether the current entry is valid (not at the end of the list)
	 *
	 * @return	$valid	Whether the current key is still valid
	 */
	public function valid () {
		// Return flag
		return $this->valid;
	}

}