<?php
/**
 * A general FileIo class
 *
 * @author		Roland Haeder <webmaster@ship-simu.org>
 * @version		0.0.0
 * @copyright	Copyright (c) 2007, 2008 Roland Haeder, 2009 - 2015 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 BaseFileIo extends BaseFrameworkSystem {
	/**
	 * The current file we are working in
	 */
	private $fileName = '';

	/**
	 * The file pointer
	 */
	private $filePointer = NULL;

	/**
	 * Protected constructor
	 *
	 * @param	$className	Name of the class
	 * @return	void
	 */
	protected function __construct ($className) {
		// Call parent constructor
		parent::__construct($className);
	}

	/**
	 * Destructor for cleaning purposes, etc
	 *
	 * @return	void
	 */
	public final function __destruct() {
		// Is there a resource pointer? Then we have to close the file here!
		if (is_resource($this->getPointer())) {
			// Try to close a file
			$this->closeFile();
		} // END - if

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

	/**
	 * 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 setPointer()
	 * @throws	InvalidResourceException	If there is being set
	 */
	private function closeFile () {
		// Debug message
		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d]: fileName=%s - CALLED!', __METHOD__, __LINE__, $this->getFileName()));

		if (is_null($this->getPointer())) {
			// Pointer not initialized
			throw new NullPointerException($this, self::EXCEPTION_IS_NULL_POINTER);
		} elseif (!is_resource($this->getPointer())) {
			// Pointer is not a valid resource!
			throw new InvalidResourceException($this, self::EXCEPTION_INVALID_RESOURCE);
		}

		// Debug message
		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d]: Closing file %s ...', __METHOD__, __LINE__, $this->getFileName()));

		// Close the file pointer and reset the instance variable
		@fclose($this->getPointer());
		$this->setPointer(NULL);
		$this->setFileName('');

		// Debug message
		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d]: EXIT!', __METHOD__, __LINE__));
	}

	/**
	 * Setter for the file pointer
	 *
	 * @param	$filePointer	File resource
	 * @return	void
	 */
	protected final function setPointer ($filePointer) {
		$this->filePointer = $filePointer;
	}

	/**
	 * Getter for the file pointer
	 *
	 * @return	$filePointer	The file pointer which shall be a valid file resource
	 */
	public final function getPointer () {
		return $this->filePointer;
	}

	/**
	 * Setter for file name
	 *
	 * @param	$fileName	The new file name
	 * @return	void
	 */
	protected final function setFileName ($fileName) {
		$fileName = (string) $fileName;
		$this->fileName = $fileName;
	}

	/**
	 * Getter for file name
	 *
	 * @return	$fileName	The current file name
	 */
	public final function getFileName () {
		return $this->fileName;
	}

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

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

	/**
	 * 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	$status		Status of file seek: 0 = success, -1 = failed
	 */
	public function seek ($offset, $whence = SEEK_SET) {
		// Seek to position
		$status = fseek($this->getPointer(), $offset, $whence);

		// Return status
		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] status=%d', __METHOD__, __LINE__, $status));
		return $status;
	}

	/**
	 * Size of this file
	 *
	 * @return	$size	Size (in bytes) of file
	 * @todo	Handle seekStatus
	 */
	public function size () {
		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] CALLED!', __METHOD__, __LINE__));

		// Get current seek position
		$seekPosition = $this->determineSeekPosition();

		// Seek to end
		$seekStatus = $this->seek(0, SEEK_END);
		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] seekStatus=%d', __METHOD__, __LINE__, $seekStatus));

		// Get position again  (which is the end of the file)
		$size = $this->determineSeekPosition();

		// Reset seek position to old
		$this->seek($seekPosition);

		// Return size
		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput(sprintf('[%s:%d:] size=%s - EXIT!', __METHOD__, __LINE__, $size));
		return $size;
	}
}

// [EOF]
?>