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

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

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

	/**
	 * Destructor for cleaning purposes, etc
	 */
	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();
		}

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

	/**
	 * Create a file pointer based on the given file. The file will also
	 * be verified here.
	 *
	 * @param	$fileName	The file name we shall pass to fopen()
	 * @param	$mode		The output mode ('w', 'a' are valid)
	 * @throws	FileIsEmptyException	If the provided file name is empty.
	 * @throws	FilePointerNotOpened	If fopen() returns not a file
	 *									resource
	 * @return	void
	 */
	public final static function createFrameworkFileOutputPointer ($fileName, $mode) {
		// Some pre-sanity checks...
		if (is_null($fileName)) {
			// No filename given
			throw new FileIsEmptyException(null, self::EXCEPTION_UNEXPECTED_EMPTY_STRING);
		}

		// Try to open a handler
		$filePointer = @fopen($fileName, $mode);
		if (($filePointer === null) || ($filePointer === false)) {
			// Something bad happend
			throw new FilePointerNotOpenedException ($fileName, self::EXCEPTION_FILE_POINTER_INVALID);
		}

		// Create new instance
		$pointerInstance = new FrameworkFileOutputPointer();

		// Set file pointer and file name
		$pointerInstance->setPointer($filePointer);
		$pointerInstance->setFileName($fileName);

		// Return the instance
		return $pointerInstance;
	}

	/**
	 * Write data to a file pointer
	 *
	 * @param	$dataStream		The data stream we shall write to the file
	 * @return	mixed			The result of fwrite()
	 * @throws	NullPointerException	If the file pointer instance
	 *									is not set by setPointer()
	 * @throws	InvalidResourceException	If there is being set
	 *											an invalid file resource
	 */
	public function writeToFile ($dataStream) {
		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);
		}

		// Read data from the file pointer and return it
		return fwrite($this->getPointer(), $dataStream);
	}

	/**
	 * 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
	 */
	public function closeFile () {
		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);
		}

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

	/**
	 * Setter for the file pointer
	 *
	 * @param	$filePointer	File resource
	 * @return	void
	 */
	public final function setPointer ($filePointer) {
		// Sanity-check if pointer is a valid file resource
		if (is_resource($filePointer) || is_null($filePointer)) {
			// Is a valid resource
			$this->filePointer = $filePointer;
		} else {
			// Throw exception
			throw new InvalidResourceException($this, self::EXCEPTION_INVALID_RESOURCE);
		}
	}

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

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

// [EOF]
?>