<?php
// Own namespace
namespace Org\Mxchange\CoreFramework\Handler\Filesystem;

// Import framework stuff
use Org\Mxchange\CoreFramework\Factory\Object\ObjectFactory;
use Org\Mxchange\CoreFramework\Generic\FrameworkInterface;
use Org\Mxchange\CoreFramework\Generic\UnsupportedOperationException;
use Org\Mxchange\CoreFramework\Handler\Stream\IoHandler;
use Org\Mxchange\CoreFramework\Middleware\BaseMiddleware;
use Org\Mxchange\CoreFramework\Middleware\Debug\DebugMiddleware;
use Org\Mxchange\CoreFramework\Traits\Streamer\File\Input\FileInputStreamerTrait;
use Org\Mxchange\CoreFramework\Traits\Streamer\File\Output\FileOutputStreamerTrait;

// Import SPL stuff
use \InvalidArgumentException;
use \SplFileInfo;

/**
 * This is a file IO handler. It handles reading from and writing to files.
 * Missing paths in writing process will be automatically created.
 *
 * @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 FileIoHandler extends BaseMiddleware implements IoHandler {
	// Load traits
	use FileInputStreamerTrait;
	use FileOutputStreamerTrait;

	/**
	 * An instance of this class
	 */
	private static $selfInstance = NULL;

	/**
	 * Protected constructor
	 *
	 * @return	void
	 */
	private function __construct () {
		// Call parent constructor
		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->traceMessage('FILE-IO-HANDLER: CONSTRUCTED!');
		parent::__construct(__CLASS__);

		// Set own instance
		self::$selfInstance = $this;

		// Trace message
		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->traceMessage('FILE-IO-HANDLER: EXIT!');
	}

	/**
	 * Creates an instance of this class and prepares the IO system. This is
	 * being done by setting the default file IO class
	 *
	 * @return	$ioHandlerInstance	A prepared instance of FilIoHandler
	 */
	public static final function createFileIoHandler () {
		// Get instance
		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->traceMessage('FILE-IO-HANDLER: CALLED!');
		$ioHandlerInstance = new FileIoHandler();

		// Set the *real* file IO instances (both the same)
		$ioHandlerInstance->setInputStreamerInstance(ObjectFactory::createObjectByConfiguredName('file_input_class'));
		$ioHandlerInstance->setOutputStreamerInstance(ObjectFactory::createObjectByConfiguredName('file_output_class'));

		// Return instance
		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->traceMessage(sprintf('FILE-IO-HANDLER: ioHandlerInstance=%s - EXIT!', $ioHandlerInstance->__toString()));
		return $ioHandlerInstance;
	}

	/**
	 * Getter for an instance of this class
	 *
	 * @return	$selfInstance	An instance of this class
	 */
	public static final function getSelfInstance () {
		// Trace message
		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->traceMessage(sprintf('FILE-IO-HANDLER: Returning self::selfInstance[]=%s - EXIT!', gettype(self::$selfInstance)));
		return self::$selfInstance;
	}

	/**
	 * Saves streamed (that are mostly serialized objects) data to files or
	 * external servers.
	 *
	 * @param	$infoInstance	An instance of a SplFileInfo class
	 * @param	$dataArray	Array containing the compressor's extension and streamed data
	 * @return	void
	 * @throws	UnsupportedOperationException	If this method is called
	 */
	public function saveFile (SplFileInfo $infoInstance, array $dataArray) {
		// Trace message for logging parameters
		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->traceMessage(sprintf('FILE-IO-HANDLER: infoInstance.pathname=%s,dataArray()=%d - CALLED!', $infoInstance->getPathname(), count($dataArray)));
		throw new UnsupportedOperationException([$this, __FUNCTION__], FrameworkInterface::EXCEPTION_UNSPPORTED_OPERATION);
	}

	/**
	 * Saves a file with data by using the current output stream
	 *
	 * @param	$infoInstance		An instance of a SplFileInfo class
	 * @param	$dataStream			File data stream
	 * @param	$objectInstance		An instance of a FrameworkInterface class (default: NULL)
	 * @return	void
	 * @throws	InvalidArgumentException	If a parameter has an invalid value
	 */
	public function saveStreamToFile (SplFileInfo $infoInstance, string $dataStream, FrameworkInterface $objectInstance = NULL) {
		// Check parameters
		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->traceMessage(sprintf('FILE-IO-HANDLER: infoInstance=%s,dataStream()=%d,objectInstance[]=%s - CALLED!', $infoInstance->__toString(), strlen($dataStream), gettype($objectInstance)));
		if (empty($dataStream)) {
			// Throw IAE
			throw new InvalidArgumentException('Parameter "dataStream" is empty', FrameworkInterface::EXCEPTION_INVALID_ARGUMENT);
		}

		// Default is this array
		$className = $this->__toString();

		// Is the object instance set?
		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugMessage(sprintf('FILE-IO-HANDLER: className=%s - BEFORE!', $className));
		if ($objectInstance instanceof FrameworkInterface) {
			// Then use this
			$className = $objectInstance->__toString();
		}

		// Send the infoInstance and data array to the output handler
		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugMessage(sprintf('FILE-IO-HANDLER: className=%s - AFTER!', $className));
		$this->getOutputStreamerInstance()->saveFile($infoInstance, [
			0 => $className,
			1 => $dataStream
		]);

		// Trace message
		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->traceMessage('FILE-IO-HANDLER: EXIT!');
	}

	/** Loads data from a file over the input handler
	 *
	 * @param	$infoInstance	An instance of a SplFileInfo class
	 * @return	$array	Array with the file contents
	 */
	public function loadFileContents (SplFileInfo $infoInstance) {
		// Read from the input handler
		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->traceMessage(sprintf('FILE-IO-HANDLER: infoInstance=%s - CALLED!', $infoInstance->__toString()));
		return $this->getInputStreamerInstance()->loadFileContents($infoInstance);
	}

	/**
	 * Determines seek position
	 *
	 * @return	$seekPosition	Current seek position
	 * @todo	0% done
	 */
	public function determineSeekPosition () {
		// Trace message
		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->traceMessage('FILE-IO-HANDLER: CALLED!');
		DebugMiddleware::getSelfInstance()->partialStub();

		// Trace message
		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->traceMessage('FILE-IO-HANDLER: EXIT!');
	}

	/**
	 * Seek to given offset (default) or other possibilities as fseek() gives.
	 *
	 * @param	$offset		Offset to seek to (or used as "base" for other seeks)
	 * @param	$whence		Added to offset (default: only use offset to seek to)
	 * @return	void
	 * @throws	InvalidArgumentException	If a parameter has an invalid value
	 */
	public function seek (int $offset, int $whence = SEEK_SET) {
		// Check parameter
		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->traceMessage(sprintf('FILE-IO-HANDLER: offset=%d,whence=%d - CALLED!', $offset, $whence));
		if ($offset < 0) {
			// Throw IAE
			throw new InvalidArgumentException('Parameter "offset" is empty', FrameworkInterface::EXCEPTION_INVALID_ARGUMENT);
		}

		// @TODO Unfinished work
		DebugMiddleware::getSelfInstance()->partialStub('offset=' . $offset . ',whence=' . $whence);

		// Trace message
		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->traceMessage('FILE-IO-HANDLER: EXIT!');
	}

	/**
	 * Size of file stack
	 *
	 * @return	$size	Size (in bytes) of file
	 * @todo	0% done
	 */
	public function size () {
		// @TODO: Unfinished method:
		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->traceMessage('FILE-IO-HANDLER: CALLED!');
		DebugMiddleware::getSelfInstance()->partialStub();

		// Trace message
		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->traceMessage('FILE-IO-HANDLER: EXIT!');
	}

	/**
	 * "Getter" for seek position
	 *
	 * @return	$seekPosition	Current seek position
	 * @todo	0% done
	 */
	public function getPosition () {
		// @TODO: Unfinished method:
		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->traceMessage('FILE-IO-HANDLER: CALLED!');
		DebugMiddleware::getSelfInstance()->partialStub();

		// Trace message
		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->traceMessage('FILE-IO-HANDLER: EXIT!');
	}

}