vbbs/app/Classes/Server.php

<?php

namespace App\Classes;

use Illuminate\Support\Facades\Log;
use Illuminate\Database\Eloquent\ModelNotFoundException;

use Sock\{SocketClient,SocketException};

use App\User;
use App\Classes\Frame as FrameClass;
use App\Models\Frame as FrameModel;
use App\Models\Mode;

abstract class Server {
	// Our Mode object, this determines if we are an ANSI or VIDEOTEX server
	private $mo = NULL;

	// The client connection object of the currently connected client.
	public $co = NULL;

	// The currently rendered Frame to the client of Frame/*
	public $fo = NULL;

	// Size of Bottom Line Pollution
	protected $blp = 0;

	// Whats on the baseline currently
	protected $baseline = '';

	// Client PID
	protected $pid = NULL;

	public function __construct(Mode $o)
	{
		$this->mo = $o;

		define('MODE_BL',           1); // Typing a * command on the baseline
		define('MODE_FIELD',        2);	// typing into an input field
		define('MODE_WARPTO',       3);	// awaiting selection of a timewarp
		define('MODE_COMPLETE',     4);	// Entry of data is complete ..
		define('MODE_SUBMITRF',     5);	// asking if should send or not.
		define('MODE_RFSENT',       6);
		define('MODE_RFERROR',      7);
		define('MODE_RFNOTSENT',    8);
		define('MODE_CONTROL',      9); // Do nothing, a method is controlling input

		define('ACTION_RELOAD',     1);
		define('ACTION_GOTO',       2);
		define('ACTION_BACKUP',     3);
		define('ACTION_NEXT',       4);
		define('ACTION_INFO',       5);
		define('ACTION_TERMINATE',  6);
		define('ACTION_SUBMITRF',   7); // Offer to submit a response frame
		define('ACTION_STAR',       8);
		define('ACTION_EDIT',       9); // Edit current frame

		define('CONTROL_TELNET',    1); // Telnet session control
		define('CONTROL_METHOD',    2); // Send input to an external method
		define('CONTROL_EDIT',      3); // Controller to edit frame

		define('TCP_IAC',       chr(255));
		define('TCP_DONT',      chr(254));
		define('TCP_DO',        chr(253));
		define('TCP_WONT',      chr(252));
		define('TCP_WILL',      chr(251));
		define('TCP_SB',        chr(250));
		define('TCP_AYT',       chr(246));
		define('TCP_SE',        chr(240));

		define('TCP_BINARY',            chr(0));
		define('TCP_OPT_ECHO',          chr(1));
		define('TCP_OPT_SUP_GOAHEAD',   chr(3));
		define('TCP_OPT_TERMTYPE',      chr(24));
		define('TCP_OPT_WINDOWSIZE',    chr(31));
		define('TCP_OPT_LINEMODE',      chr(34));

		// Status messages
		define('MSG_SENDORNOT', GREEN.'KEY 1 TO SEND, 2 NOT TO SEND');
		define('MSG_SENT',      GREEN.'MESSAGE SENT - KEY '.HASH.' TO CONTINUE');
		define('MSG_NOTSENT',   GREEN.'MESSAGE NOT SENT - KEY '.HASH.' TO CONTINUE');

		define('ERR_DATABASE',  RED.'UNAVAILABLE AT PRESENT - PLS TRY LATER');
		define('ERR_NOTSENT',   WHITE.'MESSAGE NOT SENT DUE TO AN ERROR');
		define('ERR_PRIVATE',   WHITE.'PRIVATE PAGE'.GREEN.'- FOR EXPLANATION *37'.HASH.'..');
		define('ERR_ROUTE',     WHITE.'MISTAKE?'.GREEN.'TRY AGAIN OR TELL US ON *08');
		define('ERR_PAGE',ERR_ROUTE);
		define('ERR_USER_ALREADYMEMBER',    RED.'ALREADY MEMBER OF CUG');

		define('MSG_TIMEWARP_ON',   WHITE.'TIMEWARP ON'.GREEN.'VIEW INFO WITH *02');
		define('MSG_TIMEWARP_OFF',  WHITE.'TIMEWARP OFF'.GREEN.'VIEWING DATE IS FIXED');
		define('MSG_TIMEWARP_TO',   GREEN.'TIMEWARP TO %s');
		define('MSG_TIMEWARP',      WHITE.'OTHER VERSIONS EXIST'.GREEN.'KEY *02 TO VIEW');
	}

	/**
	 * Write something to the system log.
	 *
	 * @param string $mode
	 * @param string $message
	 * @param array $data
	 */
	public function log(string $mode,string $message,array $data=[])
	{
		Log::$mode(sprintf('%s: %s',$this->pid,$message),$data);
	}

	/**
	 * Connection handler
	 *
	 * @param SocketClient $client
	 * @return bool|void
	 * @throws SocketException
	 */
	function onConnect(SocketClient $client) {
		$pid = pcntl_fork();

		if ($pid == -1)
			throw new SocketException(SocketException::CANT_ACCEPT,'Could not fork process');

		// Parent return ready for next connection
		elseif ($pid)
			return;

		// The next page we will load - this should have frame=,index=
		$next_page = NULL;

		$this->co = $client;
		$this->pid = getmypid();
		$this->log('info','Connection from: ',['client'=>$client->getAddress(),'server'=>$this->mo->name]);

		// We are now the child.
		try {
			$session = NULL;            // TCP Session Details

			$client->send(TCP_IAC.TCP_DO.TCP_OPT_SUP_GOAHEAD);     // DO SUPPRES GO AHEAD
			$client->send(TCP_IAC.TCP_WONT.TCP_OPT_LINEMODE);      // WONT LINEMODE
			$client->send(TCP_IAC.TCP_DO.TCP_OPT_ECHO);            // DO ECHO
//		    $client->send(TCP_IAC.TCP_AYT); // AYT
			$client->send(TCP_IAC.TCP_DO.TCP_OPT_TERMTYPE.TCP_IAC.TCP_SB.TCP_OPT_TERMTYPE.TCP_OPT_ECHO.TCP_IAC.TCP_SE); // Request Term Type

			$client->send(CLS.COFF);
			$client->send('Press a key...');

			// Setup VARS
			$timewarp = FALSE;          // Is timewarp active.
			$timewarpalt = FALSE;       // Alternative timewarp frame to get
			$history = collect();       // Page history for going backwards
			$action = ACTION_GOTO;      // Initial action.
			$control = FALSE;           // Logic in control
			$mode = FALSE;              // Current mode.
			$cmd = '';                  // Current *command being typed in
			$user = new User;           // The logged in user
			$method = collect();        // Method in control for CONTROL_METHOD

			$current = [];              // Attributes about the current page
			// field/fieldnum indexes are for fields on the active page
			$current['fieldreset'] = FALSE;          // Flag to reset position (used in fields)
			$current['fieldpos'] = 0;                // For current field, position within.
			$current['prevmode'] = FALSE;            // Previous mode - in case we need to go back to MODE_FIELD

			$fielddata = [];

			// @todo Get the login/start page, and if it is not available, throw the ERR_DATEBASE error.
			if (isset($config['loginpage'])) {
				$next_page = ['frame'=>$config['loginpage']];
			} else if (!empty($service['start_page'])) {
				$next_page = ['frame'=>$service['start_page']];
			} else {
				$next_page = ['frame'=>'980'];            // Default Login Page
			}

			while ($action != ACTION_TERMINATE) {
				// Read a character from the client session
				// @todo Add a timeout to read, and log user off if timeout exceeded.
				$read = $client->read(1);
				echo "\n";
				printf(". Got: %s (%s): Mode: [%s], Action: [%s], Control: [%s]\n",
					(ord($read) < 32 ? '.' : $read),
					ord($read),
					serialize($mode),
					serialize($action),
					$control);

				// It appears that read will return '' instead of false when a disconnect has occurred.
				// We'll set it to NULL so its caught later
				if ($read === '')
					$read = NULL;

				if ($read != '') {
					if ($read == TCP_IAC) {

						// If we are not already in a TELNET LOOP
						if ($control !== CONTROL_TELNET) {
							$control = CONTROL_TELNET;

							// Remember our Telnet Session Object
							if (! $session)
								$session = Control::factory('telnet',$this);

							$method->push($session);
						}
					}

					if ($control AND $method->count()) {
						printf("= Start CONTROL: Going to method: %s\n",get_class($method->last()));

						// Capture our state when we enter this method.
						if (! array_key_exists('control',$method->last()->state)) {
							$method->last()->state['control'] = $control;
							$method->last()->state['action'] = $action;
						}

						$method->last()->state['mode'] = $mode;
						$action = FALSE;

						// Pass Control to Method
						$read = $method->last()->handle($read,$current);
						$mode = $method->last()->state['mode'];

						if ($method->last()->complete()) {
							printf("- Complete CONTROL: %s\n",get_class($method->last()));
							$save = $method->pop();

							if ($method->count()) {
								$control = $method->last()->state['control'];

							} else {
								$mode = $save->state['mode'];
								$action = $save->state['action'];
								$control = FALSE;
							}

							dump(sprintf('End: Control is now: %s: Method Count: %s',is_object($control) ? get_class($control) : serialize($control),$method->count()));
						}

						printf("- End CONTROL: Read %s (%s): Mode: [%s], Action: [%s], Control: [%s]\n",
							(ord($read) < 32 ? '.' : $read),
							ord($read),
							serialize($mode),
							serialize($action),
							$control);
					}

					printf("= Start MODE: %s\n",serialize($mode));
					switch ($mode) {
						// Key presses during field input.
						case MODE_FIELD:
							$cmd = '';
							$action = FALSE;

							switch ($this->fo->type()) {
								// Login frame.
								case Frame::FRAMETYPE_LOGIN:
									switch ($read) {
										case HASH:
											// If we are the main login screen, see if it is a new user
											if ($this->fo->isCUG(0))
											{
												if ($current['field']->type == 't' AND array_get($fielddata,$current['fieldnum']) == 'NEW')
												{
													$action = ACTION_GOTO;
													$next_page = ['frame'=>'981']; // @todo This should be in the DB.

													break 2;
												}
											}

											break;
									}

								// Response frame.
								case Frame::FRAMETYPE_ACTION:
									switch ($read) {
										// End of field entry.
										case LF:
										case HASH:
											// Next Field
											$current['fieldnum']++;
											$current['fieldpos'] = 0;

											if ($current['fieldnum'] < $this->fo->fields()->count()) {
												$current['fieldnum'] = $this->fo->getFieldId('edit',$current['fieldnum']);

												if ($current['fieldnum'] !== FALSE) {
													$current['field'] = $this->fo->getField($current['fieldnum']);

													$client->send($this->moveCursor($current['field']->x,$current['field']->y).CON);
													$mode = MODE_FIELD;

												// There were no (more) editable fields.
												} else {
													$action = ACTION_SUBMITRF;
												}

											} else {
												// Finished all editable fields.
												$action = ACTION_SUBMITRF;
											}

											break;

										case STAR:
											$current['prevmode'] = MODE_FIELD;
											$action = ACTION_STAR;
											$current['fieldpos'] = 0;
											$fielddata[$current['fieldnum']] = '';
											$current['fielddata'][$current['fieldnum']] = '';

											break;

										case KEY_DELETE:
											if ($current['fieldpos'])
											{
												$current['fieldpos']--;
												$client->send(LEFT.$this->fo::$if_filler.LEFT);
												$fielddata[$current['fieldnum']] = substr($fielddata[$current['fieldnum']],0,-1);
												$current['fielddata'][$current['fieldnum']] = substr($current['fielddata'][$current['fieldnum']],0,-1);
											}

											break;

										case KEY_LEFT:
											if ($current['fieldpos']) {
												$current['fieldpos']--;
												$client->send(LEFT);
											}

											break;

										case KEY_RIGHT:
											if ($current['fieldpos']++ < $current['field']->length)
												$client->send(RIGHT);

											break;

										case KEY_DOWN:
											if ($current['fieldpos'] + 40 < $current['field']->length) {
												$client->send(DOWN);
												$current['fieldpos'] = $current['fieldpos'] + 40;
											};

											break;

										case KEY_UP:
											if ($current['fieldpos'] - 40 >= 0) {
												$client->send($read);
												$current['fieldpos'] = $current['fieldpos'] - 40;
											};

											break;

										case CR:
											// On second or later line of a field
											if ($current['fieldpos'] + $current['field']->x > 40) {
												$client->send($read);
												$current['fieldpos'] = (($current['fieldpos'] + $current['field']->x) % 40) * 40;

											} else {
												$client->send($this->moveCursor($current['field']->x,$current['field']->y).CON);
												$current['fieldpos'] = 0;
											}

											break;

										case ESC:
											break;

										// Record Data Entry
										default:
											if (ord($read) > 31 && $current['fieldpos'] < $current['field']->length) {
												if (! array_key_exists($current['fieldnum'],$current['fielddata'])) {
													$current['fielddata'][$current['fieldnum']] = '';
													$fielddata[$current['fieldnum']] = '';
												}

												$fielddata[$current['fieldnum']]{$current['fieldpos']} = $read; // @todo delete
												$current['fielddata'][$current['fieldnum']]{$current['fieldpos']} = $read;

												$current['fieldpos']++;

												$client->send($this->fo->isFieldMasked($current['field']->type) ?: $read);
											}
									}

									break;

								// Other Frame Types - Shouldnt get here.
								default:
									$client->close();

									throw new \Exception('Shouldnt get here',500);
							}

							break;

						// Form submission: 1 to send, 2 not to send.
						case MODE_SUBMITRF:
							switch ($read) {
								case '1':
									// If we are in a control method, complete it
									if ($control AND $method->count()) {
										$method->last()->process();

									} elseif ($this->fo->route(1) == '*' OR is_numeric($this->fo->route(1))) {
										$this->sendBaseline($client,RED.'NO ACTION PERFORMED');
										$mode = MODE_RFSENT;

									} elseif ($ao = FrameClass\Action::factory($this->fo->route(1),$this,$user,$action,$mode)) {
										$ao->handle($fielddata);
										$mode = $ao->mode;
										$action = $ao->action;

										// Is this a user logging in?
										if ($ao->uo->exists AND $ao instanceof FrameClass\Action\Login)
										{
											$user = $ao->uo;
											$history = collect();
										}

										if ($ao->page)
											$next_page = $ao->page;

									} else {
										$this->sendBaseline($client,RED.'NO method exists...');

										$mode = MODE_RFSENT;
									}

									break;

								case '2':
									$this->sendBaseline($client,MSG_NOTSENT);
									$mode = MODE_RFNOTSENT;

									// If a Control method was rejected, we can clear it
									if ($control AND $method->count()) {
										$save = $method->pop();

										if ($method->count()) {
											$control = $method->last()->state['control'];

										} else {
											$mode = $save->state['mode'];
											$action = $save->state['action'];
											$control = FALSE;
										}
									}

									break;

								case STAR:
									$action = ACTION_STAR;

									break;
							}

							break;

						// Response form after Sent processing
						case MODE_RFSENT:
							$client->send(COFF);

							if ($read == HASH) {
								if ($x = $this->fo->route(2) AND $x !== '*' AND is_numeric($x)) {
									$next_page = ['frame'=>$x];

								} elseif (FrameModel::where('frame',$this->fo->frame())->where('index',$this->fo->index_next())->exists()) {
									$next_page = ['frame'=>$this->fo->frame(),'index'=>$this->fo->index_next()];

								} elseif ($x = $this->fo->route(0) AND $x !== '*' AND is_numeric($x)) {
									$next_page = ['frame'=>$x];

								// No further routes defined, go home.
								} else {
									$next_page = ['frame'=>0];
								}

								$action = ACTION_GOTO;

							} elseif ($read == STAR) {
								$action = ACTION_STAR;

								break;
							}

							break;

						// Response form after NOT sending
						case MODE_RFNOTSENT:

						// Response form ERROR
						case MODE_RFERROR:
							$client->send(COFF);

							if ($read == HASH) {
								if ($x = $this->fo->route(2) AND $x !== '*' AND is_numeric($x)) {
									$next_page = ['frame'=>$x];

								} elseif (FrameModel::where('frame',$this->fo->frame())->where('index',$this->fo->index_next())->exists()) {
									$next_page = ['frame'=>$this->fo->frame(),'index'=>$this->fo->index_next()];

								} elseif ($x = $this->fo->route(0) AND $x !== '*' AND is_numeric($x)) {
									$next_page = ['frame'=>$x];

								// No further routes defined, go home.
								} else {
									$next_page = ['frame'=>0];
								}

								$action = ACTION_GOTO;

							} elseif ($read == STAR) {
								$action = ACTION_STAR;

								break;
							}

							break;

						// List of alternate frames has been presented
						case MODE_WARPTO:
							if (is_numeric($read) AND $read) {
								$timewarpalt = $alts->get($read-1)->id;
								$action = ACTION_GOTO;

							} elseif ($read === '0') {
								$action = ACTION_RELOAD;
							}

							break;

						// Not doing anything in particular.
						case MODE_COMPLETE:
						case FALSE:
							$this->log('debug','Idle');
							$cmd = '';

							switch ($read) {
								case HASH:
									$action = ACTION_NEXT;
									break;

								case STAR:
									$action = ACTION_STAR;
									break;

								// Frame Routing
								case '0':
								case '1':
								case '2':
								case '3':
								case '4':
								case '5':
								case '6':
								case '7':
								case '8':
								case '9':
									if (is_numeric($this->fo->route($read))) {
										$next_page = ['frame'=>$this->fo->route($read)];

										$action = ACTION_GOTO;

									} else {
										$this->sendBaseline($client,ERR_ROUTE);
										$mode = $action = FALSE;
									}

									break;
							}

							break;

						// Currently accepting baseline input after a * was received
						case MODE_BL:
							echo "- Waiting for Page Number\n";

							// if it's a number, continue entry
							if (strpos('0123456789',$read) !== FALSE) {
								$client->send($read);
								$this->blp++;
								$cmd .= $read;
							}

							// If its a backspace, delete last input
							if ($read === KEY_DELETE AND strlen($cmd))
							{
								$client->send(BS.' '.BS);
								$this->blp--;
								$cmd = substr($cmd,0,-1);
							}

							// if we hit a special numeric command, deal with it.
							// Refresh page
							if ($cmd === '00') {
								$client->send(COFF);
								$action = ACTION_RELOAD;
								$cmd = '';

								break;
							}

							// Toggle Timewarp Mode
							// @todo in forms, the cursor is in the wrong location for ANSI
							if ($cmd === '01') {
								$client->send(COFF);
								$timewarp = !$timewarp;
								$this->sendBaseline($client,($timewarp ? MSG_TIMEWARP_ON : MSG_TIMEWARP_OFF));
								$cmd = '';
								$action = $mode = FALSE;

								break;
							}

							// Present Timewarp Frames
							// @todo in forms, the cursor is in the wrong location for ANSI
							if ($cmd === '02') {
								$client->send(COFF);
								$action = ACTION_INFO;
								$cmd = '';

								break;
							}

							// Edit frame
							// Catch if we are going to edit a child frame
							if (preg_match('/^04/',$cmd) AND preg_match('/^[a-z]$/',$read))
							{
								$client->send(COFF);
								$next_page = ['frame'=>substr($cmd,2),'index'=>$read];
								$cmd = '';

								$action = ACTION_EDIT;

								break;
							}

							// Bookmark page
							if ($cmd === '05') {
								$this->sendBaseline($client,RED.'NOT IMPLEMENTED YET?');
								$mode = FALSE;

								break;
							}

							// Report a problem
							if ($cmd === '08') {
								$this->sendBaseline($client,RED.'NOT IMPLEMENTED YET?');
								$mode = FALSE;

								break;
							}

							// Reload page
							if ($cmd === '09') {
								$client->send(COFF);
								$action = ACTION_GOTO;
								$cmd = '';
								$next_page = $this->fo->page(TRUE);

								break;
							}

							// Another star aborts the command.
							if ($read === STAR) {
								$action = FALSE;
								$this->sendBaseline($client,array_get($current,'baseline',''));
								$cmd = '';

								if ($current['prevmode'] == MODE_FIELD) {
									$mode = $current['prevmode'];
									$current['prevmode'] = FALSE;

									// @todo The cursor color could be wrong
									$client->send($this->moveCursor($current['field']->x,$current['field']->y).CON);
									$client->send(str_repeat($this->fo::$if_filler,$current['field']->length));
									$current['fieldreset'] = TRUE;

								} else {
									$mode = FALSE;
								}

								break;
							}

							// Complete request
							if ($read === HASH or $read === LF) {
								$client->send(COFF);
								$timewarpalt = FALSE;

								// If input is in a control, terminate it
								if ($control)
								{
									$method->pop();
									$control = FALSE;

									// Our method count should be zero
									if ($method->count())
										dd($method);
								}

								// Nothing typed between * and #
								// *# means go back
								if ($cmd === '') {
									$action = ACTION_BACKUP;

								} elseif ($cmd === '0') {
									$next_page = ['frame'=>$user->exists ? 1 : 980]; // @todo Get from DB.
									$action = ACTION_GOTO;

								// Edit Frame
								} elseif (preg_match('/^04/',$cmd)) {
									$client->send(COFF);
									$action = ACTION_EDIT;
									$next_page = [
										'frame' => substr($cmd,2) ?: $this->fo->frame(),
									];

								} else {
									$next_page = ['frame'=>$cmd];
									$action = ACTION_GOTO;
								}

								// Clear the command, we are finished processing
								$cmd = '';

								break;
							}

							break;

						// Control is taking input
						case MODE_CONTROL:
							break;

						default:
							$this->log('debug','Not sure what we were doing?');
					}

					printf("- End MODE: Read %s (%s): Mode: [%s], Action: [%s], Control: [%s]\n",
						(ord($read) < 32 ? '.' : $read),
						ord($read),
						serialize($mode),
						serialize($action),
						$control);
				}

				// This section performs some action if it is deemed necessary
				printf("= Start ACTION: %s\n",serialize($action));

				switch ($action) {
					case ACTION_STAR:
						echo "+ Star command...\n";

						// If there is something on the baseline, lets preserve it
						if ($this->blp)
						{
							printf(". Preserving Baseline: %s\n",$this->baseline);
							$current['baseline'] = $this->baseline;
						}

						$this->sendBaseline($client,GREEN.STAR,TRUE);
						$client->send(CON);
						$action = FALSE;
						$mode = MODE_BL;

						break;

					case ACTION_SUBMITRF:
						$action = FALSE;
						$client->send(COFF);
						$this->sendBaseline($client,MSG_SENDORNOT);
						$mode = MODE_SUBMITRF;

						break;

					// Edit Frame
					case ACTION_EDIT:
						$this->log('debug','Editing frame:',[$next_page]);

						$next_fo = NULL;
						// If we are editing a different frame, load it
						try {
							$next_fo = $this->mo->framePage($next_page['frame'],array_get($next_page,'index','a'),$this);

						} catch (ModelNotFoundException $e) {
							$next_fo = $this->mo->frameNew($this,$next_page['frame'],$next_page['index']);
						}

						$control = CONTROL_EDIT;
						$method->push(Control::factory('editframe',$this,$next_fo));
						$next_fo = NULL;
						$method->last()->state['control'] = $control;
						$method->last()->state['action'] = FALSE;
						$method->last()->state['mode'] = MODE_FIELD;
						$mode = MODE_CONTROL;
						$action = FALSE;

						break;

					// GO Backwards
					case ACTION_BACKUP:
						// Do we have anywhere to go, drop the current page from the history.
						if ($history->count() > 1)
							$history->pop();

						if ($control AND $method->count()) {
							$save = $method->pop();

							// Do we still have more nested methods to complete
							if ($method->count()) {
								$control = $method->last()->state['control'];

							} else {
								$mode = $save->state['mode'];
								$action = $save->state['action'];
								$control = FALSE;
							}
						}

						$next_page = $history->last();

						// If there is no next page, we'll refresh the current page.
						if ($next_page)
							$this->log('debug','Backing up to:',$next_page);

					// Go to next index frame.
					case ACTION_NEXT:
						// We need this extra test in case we come from ACTION_BACKUP
						if ($action == ACTION_NEXT)
						{
							$current['page']['index'] = $this->fo->index();
							$next_page = ['frame'=>$this->fo->frame(),'index'=>$this->fo->index_next()];
						}

					// Look for requested page - charge for it to be loaded.
					case ACTION_GOTO:
						if ($next_page OR $timewarpalt)
						{
							// If we wanted a "Searching..." message, this is where to put it.
							try {
								// Store our next frame in a temporary var while we determine if it can be displayed
								$fo = $timewarpalt
									? $this->mo->frameID($timewarpalt)
									: $this->mo->framePage($next_page['frame'],array_get($next_page,'index','a'),$this);

								$this->log('debug',sprintf('Fetched frame: %s (%s)',$fo->id(),$fo->page()));

							} catch (ModelNotFoundException $e) {
								// @todo Make sure parent frame exists, or display error
								$this->sendBaseline($client,ERR_PAGE);
								$mode = $action = FALSE;

								if (! $fo)
									$fo = $this->mo->frameTest($this);

								break;
							}

							// Is there a user logged in
							if ($user)
							{
								if ($fo->isFramePublic() AND $fo->isAccessible())
								{
									if ($fo->type() == Frame::FRAMETYPE_LOGIN AND $user->isMemberCUG($fo->getCUG()))
									{
										$this->sendBaseline($client,ERR_USER_ALREADYMEMBER);
										$next_page = $history->last();
										$mode = $action = FALSE;
										$this->log('debug',sprintf('Frame Denied - Already Member: %s (%s)',$fo->id(),$fo->page()));

										break;
									}


								// If this is a login frame and the user is already a member.
								} else {
									if (! $fo->isOwner($user))
									{
										if (! $fo->isAccessible())
										{
											$this->sendBaseline($client,ERR_PAGE);
											$next_page = $history->last();
											$mode = $action = FALSE;
											$this->log('debug',sprintf('Frame Denied - In Accessible: %s (%s)',$fo->id(),$fo->page()));

											break;
										}

										if (! $user->isMemberCUG($fo->getCUG()))
										{
											$this->sendBaseline($client,ERR_PRIVATE);
											$next_page = $history->last();
											$mode = $action = FALSE;
											$this->log('debug',sprintf('Frame Denied - Not in CUG [%s]: %s (%s)',$fo->getCUG()->id,$fo->id(),$fo->page()));

											break;
										}
									}
								}

							} else {
								// Is this a public frame in CUG 0?
								if (! $fo->isCUG(0) OR ! $fo->isFramePublic())
								{
									$this->sendBaseline($client,ERR_PAGE);
									$next_page = $history->last();
									$mode = $action = FALSE;

									break;
								}
							}
						}

						// Only if new location, not going backwards
						if (($history->last() != $next_page) AND ($action == ACTION_GOTO || $action == ACTION_NEXT)) {
							$history->push($next_page);
						}

						$current['fieldpos'] = 0;
						$this->fo = $fo;
						$fo = NULL;
						$next_page = NULL;
						$timewarpalt = NULL;

						printf("+ Mode is: %s\n",$mode);

					// drop into
					case ACTION_RELOAD:
						// Clear the baseline history
						$this->sendBaseline($client,'');
						$current['baseline'] = '';

						$output = (string)$this->fo;

						if ($timewarpalt) {
							$this->sendBaseline($client,sprintf(MSG_TIMEWARP_TO,$this->fo->created() ? $this->fo->created()->format('Y-m-d H:i:s') : 'UNKNOWN'));
						}

						switch ($this->fo->type()) {
							default:
							// Standard Frame
							case Frame::FRAMETYPE_INFO:
								$client->send($output);
								$mode = $action = FALSE;

								break;

							// Login Frame.
							case Frame::FRAMETYPE_LOGIN:
								$client->send($output);
								$action = FALSE;
								$output = '';

								// If this is the registration page
								// @todo Should be evaluated out of the DB
								if ($this->fo->page() == '981a') {
									$control = CONTROL_METHOD;
									$method->push(Control::factory('register',$this));
									$method->last()->state['control'] = $control;
									$method->last()->state['action'] = FALSE;
									$method->last()->state['mode'] = MODE_FIELD;
								}

							// Active Frame. Prestel uses this for a Response Frame.
							case Frame::FRAMETYPE_ACTION:
								$client->send($output);
								// holds data entered by user.
								$fielddata = [];
								$current['fielddata'] = [];

								if ($this->fo->fields()->count()) {
									// Get our first editable field.
									$current['fieldnum'] = $this->fo->getFieldId('edit',0);
									$current['field'] = $this->fo->getField($current['fieldnum']);
									$current['fieldreset'] = TRUE;

									if ($current['fieldnum'] !== FALSE) {
										$mode = MODE_FIELD;

										// There were no editable fields.
									} else {
										$mode = MODE_COMPLETE;
										$client->send(COFF);
									}

									$current['fieldpos'] = 0;

								} else {
									$mode = FALSE;
								}

								break;

							// Terminate Frame
							case Frame::FRAMETYPE_TERMINATE:
								$client->send($output);
								$action = ACTION_TERMINATE;

								break;
						}

						break;

					// Timewarp Mode
					case ACTION_INFO:
						$mode = $action = FALSE;
						$cmd = '';
						$y = 0;

						$output = $this->moveCursor(0,$y++).WHITE.NEWBG.RED.'TIMEWARP INFO FOR Pg.'.BLUE.$this->fo->page().WHITE;
						//$output .= $this->moveCursor(0,$y++).WHITE.NEWBG.BLUE.'Service : '.substr($service['service_name'].str_repeat(' ',27),0,27);
						//$output .= $this->moveCursor(0,$y++).WHITE.NEWBG.BLUE.'Varient : '.substr($varient['varient_name'].str_repeat(' ',27),0,27);
						$output .= $this->moveCursor(0,$y++).WHITE.NEWBG.BLUE.'Dated   : ' .substr(($this->fo->created() ? $this->fo->created()->format('j F Y') : 'Unknown').str_repeat(' ',27),0,27);

						$alts = $this->fo->alts($this->mo)->get();

						if (count($alts)) {
							$n = 1;

							$output .= $this->moveCursor(0,$y++).WHITE.NEWBG.RED.'ALTERNATIVE VERSIONS:'.str_repeat(' ',16);

							foreach ($alts as $o) {
								$date = $o->created_at->format('d M Y');

								$line = WHITE.NEWBG;

								if ($timewarp) {
									$line .= RED.$n++;
								}

								$line .= BLUE.$date.' '.$o->note;

								$output .= $this->moveCursor(0,$y++).$line.str_repeat(' ',40-$this->fo->strlenv($line)); // @todo should use frame::page_length
							}

							if ($timewarp) {
								$mode = MODE_WARPTO;
							}

						}

						$client->send($output);

						break;
				}

				printf("- End ACTION: Read %s (%s): Mode: [%s], Action: [%s], Control: [%s]\n",
					(ord($read) < 32 ? '.' : $read),
					ord($read),
					serialize($mode),
					serialize($action),
					$control);

				// We need to reposition the cursor to the current field.
				if ($current['fieldreset'] !== FALSE) {
					$client->send($this->moveCursor($current['field']->x,$current['field']->y).CON);
					$current['fieldreset'] = FALSE;
				}

				// Did the client disconnect
				if ($read === NULL || socket_last_error()) {
					$client->close();
					$this->log('debug',sprintf('Client Disconnected: %s',$client->getaddress()));

					return;
				}
			}

			// Something bad happened. We'll log it and then disconnect.
		} catch (\Exception $e) {
			Log::emergency($e->getMessage(),['line'=>$e->getLine(),'file'=>$e->getFile()]);
		}

		$client->close();
		$this->log('debug',sprintf('Disconnected: %s',$client->getaddress()));
	}

	/**
	 * Move the cursor via the shortest path.
	 */
	abstract function moveCursor($x,$y);

	/**
	 * Send a message to the base line
	 *
	 * @note "$this->blp" remembers how many chars are there, so that they can be replace with next call
	 * @param $client
	 * @param $text
	 * @param bool $reposition
	 */
	abstract function sendBaseline($client,$text,$reposition=FALSE);
}