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

// Import framework stuff
use Org\Mxchange\CoreFramework\Filesystem\CloseableFile;
use Org\Mxchange\CoreFramework\Filesystem\FilePointer;
use Org\Mxchange\CoreFramework\Generic\FrameworkInterface;
use Org\Mxchange\CoreFramework\Generic\NullPointerException;
use Org\Mxchange\CoreFramework\Object\BaseFrameworkSystem;

// Import SPL stuff
use \OutOfBoundsException;
use \SplFileObject;

/**
 * A general FileIo class
 *
 * @author		Roland Haeder <webmaster@ship-simu.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.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/>.
 */
abstract class BaseFileIo extends BaseFrameworkSystem implements FilePointer, CloseableFile {
	/**
	 * The file object
	 */
	private $fileObject = NULL;

	/**
	 * Protected constructor
	 *
	 * @param	$className	Name of the class
	 * @return	void
	 */
	protected function __construct (string $className) {
		// Call parent constructor
		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->traceMessage(sprintf('BASE-FILE-IO: className=%s - CONSTRUCTED!', $className));
		parent::__construct($className);

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

	/**
	 * Destructor for cleaning purposes, etc
	 *
	 * @return	void
	 */
	public final function __destruct() {
		// Is there a resource pointer? Then we have to close the file here!
		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->traceMessage(sprintf('BASE-FILE-IO: this->fileObject[]=%s - DESTRUCTOR!', gettype($this->getFileObject())));
		if (is_object($this->getFileObject())) {
			// Try to close a file
			/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->traceMessage('BASE-FILE-IO: Invoking this->closeFile() ...');
			$this->closeFile();
		}

		// Call the parent destructor
		parent::__destruct();

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

	/**
	 * Close a file source and set it's instance to null and the file name
	 * to empty.
	 *
	 * @return	void
	 * @throws	NullPointerException	If the file pointer instance is not set by setFileObject()
	 * @throws	LogicException	If there is no object being set
	 */
	public function closeFile () {
		// Validate parameter
		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->traceMessage(sprintf('BASE-FILE-IO: fileName=%s - CALLED!', $this->getFileObject()->getPathname()));
		if (is_null($this->getFileObject())) {
			// Pointer not initialized
			throw new NullPointerException($this, FrameworkInterface::EXCEPTION_IS_NULL_POINTER);
		} elseif (!is_object($this->getFileObject())) {
			// Pointer is not a valid resource!
			throw new LogicException(sprintf('this->fileObject[]=%s is no object', gettype($this->getFileObject())), FrameworkInterface::EXCEPTION_LOGIC_EXCEPTION);
		}

		// Close the file pointer by NULL-ing it
		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugMessage(sprintf('BASE-FILE-IO: Closing file %s ...', $this->getFileObject()->getPathname()));
		$this->resetFileObject();

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

	/**
	 * Resets file object instance to NULL
	 *
	 * @return	void
	 */
	protected final function resetFileObject () {
		// Set it to NULL
		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->traceMessage('BASE-FILE-IO: Setting this->fileObject=NULL - CALLED!');
		$this->fileObject = NULL;

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

	/**
	 * Setter for the file object
	 *
	 * @param	$fileObject		An instance of a SplFileObject class
	 * @return	void
	 */
	protected final function setFileObject (SplFileObject $fileObject) {
		$this->fileObject = $fileObject;
	}

	/**
	 * Getter for the file object
	 *
	 * @return	$fileObject		An instance of a SplFileObject class
	 */
	public final function getFileObject () {
		return $this->fileObject;
	}

	/**
	 * Determines seek position
	 *
	 * @return	$seekPosition	Current seek position
	 */
	public final function determineSeekPosition () {
		return $this->getFileObject()->ftell();
	}

	/**
	 * Determines whether the EOF has been reached
	 *
	 * @return	$isEndOfFileReached		Whether the EOF has been reached
	 */
	public final function isEndOfFileReached () {
		return $this->getFileObject()->eof();
	}

	/**
	 * 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	$status		Status of file seek: 0 = success, -1 = failed
	 */
	public function seek (int $offset, int $whence = SEEK_SET) {
		// Validate parameter
		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->traceMessage(sprintf('BASE-FILE-IO: offset=%d,whence=%d - CALLED!', $offset, $whence));
		if ($offset < 0) {
			// Throw exception
			throw new OutOfBoundsException(sprintf('offset=%d is not valid', $offset));
		}

		// Seek to position
		$status = $this->getFileObject()->fseek($offset, $whence);

		// Return status
		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->traceMessage(sprintf('BASE-FILE-IO: status=%d - EXIT!', $status));
		return $status;
	}

	/**
	 * Size of this file
	 *
	 * @return	$size	Size (in bytes) of file
	 * @todo	Handle seekStatus
	 */
	public function size () {
		// Get current seek position
		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->traceMessage('BASE-FILE-IO: CALLED!');
		$seekPosition = $this->determineSeekPosition();

		// Seek to end
		$seekStatus = $this->seek(0, SEEK_END);

		// Get position again (which is the end of the file)
		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugMessage(sprintf('BASE-FILE-IO: seekStatus[%s]=%d', gettype($seekStatus), $seekStatus));
		$size = $this->determineSeekPosition();

		// Reset seek position to old
		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugMessage(sprintf('BASE-FILE-IO: size[%s]=%d', gettype($size), $size));
		$this->seek($seekPosition);

		// Return size
		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->traceMessage(sprintf('BASE-FILE-IO: size=%d - EXIT!', $size));
		return $size;
	}

}