<?php
/**
 * FTP wrapper class
 * @author Tjaart Viljoen
 * @copyright 2013 Nirph Online
 */
namespace Utility\Remote;

class Ftp
{
	protected $_serverAddress;
	protected $_connection;
	protected $_username;
	protected $_password;
	protected $_verbose;
	protected $_timeout = 60;

	/**
	 * Class constructor.
	 * Set default parameters.
	 * @param string $serverAddress
	 * @param string $username
	 * @param string $password
	 */
	function __construct($serverAddress, $username, $password, $timeout = 60, $verbose = false)
	{
		$this->_serverAddress = $serverAddress;
		$this->_username	  = $username;
		$this->_password	  = $password;
		$this->_verbose		  = $verbose;
		$this->_timeout		  = $timeout;
	}

	/**
	 * Change remote FTP directory.
	 * @param unknown $directory
	 * @throws \ErrorException
	 * @return boolean
	 */
	public function changeDirectory($directory)
	{
		$this->_secureConnection();
		$this->_output('Changing directory to "' . $directory . '"');
		$result = ftp_chdir($this->_connection, $directory);

		if(false == $result)
		{
			error_log('Couldn\'t change to FTP directory "' . $directory . '"');
			throw new \Exception('Couldn\'t change to FTP directory "' . $directory . '"');
			return false;
		}
		return $result;
	}

	/**
	 * Create a new remote directory.
	 * @param string $directory
	 * @throws \Exception
	 * @return boolean
	 */
	public function createDirectory($directory)
	{
		$this->_secureConnection();
		$this->_output('Creating directory "' . $directory . '"');
		$result = ftp_mkdir($this->_connection, $directory);
		if(false == $result)
		{
			$error = 'Couldn\'t create remote FTP directory "' . $directory . '"' ;
			error_log($error);
			throw new \Exception($error);
			return false;
		}
		return true;
	}

	/**
	 * Connect to the remote server.
	 * @throws \Exception
	 * @return \Utility\Remote\Ftp
	 */
	public function connect()
	{
		$this->_connection = ftp_connect($this->_serverAddress);

		if(false == $this->_connection)
		{
			throw new \Exception("Couldn't connect to FTP server: " . $this->_serverAddress );
		}
		$this->_output('Connected to "' . $this->_serverAddress . '"');
		return $this;
	}

	/**
	 * Close the remote FTP server connection.
	 */
	public function closeConnection()
	{
		$this->_output('Closing FTP connection');
		ftp_close($this->_connection);
		$this->_connection = null;
	}

	/**
	 * Login to the remote FTP server.
	 * @throws \Exception
	 * @return \Utility\Remote\Ftp
	 */
	protected function _login()
	{
		$this->_output('Logging in to "' . $this->_serverAddress . '"');
		$logingResult = ftp_login($this->_connection, $this->_username, $this->_password);

		if(false == $logingResult)
		{
			$this->_output('Login failure');
			$this->closeConnection();
			throw new \Exception("Couldn't log into remote server, please check your credentials and try again");
		}
		$this->_output('Logged in to "' . $this->_serverAddress . '"');
		return $this;
	}

	/**
	 * $return the content of a directory.
	 * Returns an empty array on error.
	 * @param string $directory
	 * @return array
	 */
	public function getDirectoryContents($directory = '.')
	{
		$this->_secureConnection();
		$this->_output('Retrieving direcory contents for "' . $directory . '"');
		$contents = ftp_nlist($this->_connection, '.');

		if(false == $contents)
		{
			error_log('Couldn\'t retrieve directory contents for: ' . $this->_serverAddress . ', directory: "' . $directory . '"');
			return array();
		}
		return $contents;
	}

	/**
	 * Delete a remote Directory
	 * @example deleteRemoteDirectory('./relative-path-directory');
	 * @example deleteRemoteDirectory('/temp/absolute-path-directory');
	 * @param string $directory
	 * @return boolean
	 */
	public function deleteRemoteDirectory($directory)
	{
		$this->_secureConnection();
		$this->_output('Deleting direcory "' . $directory . '"');
		$result = ftp_rmdir($this->_connection, $directory);

		if(false == $result)
		{
			error_log('Couldn\'t delete remote FTP directory "' . $directory . '"');
			return false;
		}

		return true;
	}

	/**
	 * Delete a remote file
	 * @param string $filename
	 * @return boolean
	 */
	public function deleteRemoteFile($filename)
	{
		$this->_secureConnection();
		$this->_output('Deleting file "' . $filename . '"');
		$result = ftp_delete($this->_connection, $filename);

		if(false == $result)
		{
			error_log('Couldn\'t delete remote FTP file "' . $filename . '"');
			return false;
		}

		return true;
	}

	/**
	 * Download a remote file to a specified location.
	 * @param string $localFilename
	 * @param string $remoteFilename
	 * @throws \Exception
	 * @return void|boolean
	 */
	public function downloadFile($localFilename, $remoteFilename)
	{
		set_time_limit(0);
		$this->_secureConnection();
		$this->_output('Downloading file"' . $remoteFilename . '" to "' . $localFilename . '"');
		ftp_pasv($this->_connection, true);
		if(ftp_get($this->_connection, $localFilename, $remoteFilename, FTP_BINARY))
		{
			ftp_pasv($this->_connection, false);
			return true;
		}
		ftp_pasv($this->_connection, false);
		return false;
	}

	/**
	 * Upload a specified file.
	 * @param string $localFilename
	 * @param string $remoteFilename
	 * @throws \Exception
	 * @return void|boolean
	 */
	public function uploadFile($localFilename, $remoteFilename, $mode = FTP_BINARY)
	{
		set_time_limit(0);
		$this->_secureConnection();
		$this->_output('Uploading file"' . $localFilename . '" to "' . $remoteFilename . '"');
		ftp_pasv($this->_connection, true);
		if(ftp_put($this->_connection, $remoteFilename, $localFilename, $mode))
		{
			ftp_pasv($this->_connection, false);
			return true;
		}

		ftp_pasv($this->_connection, false);

		$error = 'Couldn\'t upload "' . $localFilename . '" to remote location "' . $remoteFilename . '"';
		error_log($error);
		throw new \Exception($error);
		return false;
	}

	/**
	 * Checks the connection and reconnects to the remote FTP server if necessary
	 */
	protected function _secureConnection()
	{
		if(null == $this->_connection)
		{
			$this->connect();
			$this->_login();
		}
	}

	/**
	 * Returns the present working directory
	 * @return string
	 */
	public function whereAmI()
	{
		$this->_secureConnection();
		return (string) ftp_pwd($this->_connection);
	}

	protected function _output($string)
	{
		if(false == $this->_verbose)
		{
			return;
		}
		echo $string . PHP_EOL;
	}
}