/**

* Copyright (C) 2013 Tyler Romeo, Krzysztof Jordan, Nicholas Bevaqua

*

* 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 2 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, write to the Free Software Foundation, Inc.,

* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.

* http://www.gnu.org/copyleft/gpl.html

*/

/**

* Controller class to handle execution of commands

* @constructor

*/

function WebBash( username ) {

'use strict';

/**

* Terminal environment variables

* @private

* @type {Object.<string>}

*/

this.environment = { '?': '0' };

/**

* Terminal alias commands

* @private

* @type {Object.<string, string>}

*/

this.aliasCommands = {};

/**

* Regular expression for validating environment variable names

* @private

* @const

* @type {RegExp}

*/

this.varPatt = /[\w\?\-\!]+/i;

/**

* The username of the current user

* @private

* @const

* @type {string}

*/

this.username = username;

/**

* Marker for where the API loaded the history from

* @private

* @type {number}

*/

this.historyMarker = 0;

/**

* API object for making API calls

* @type {WebBashApi}

* @private

* @cosnt

*/

this.api = new WebBashApi();

/**

* Startup function

* @param {Terminal} terminal

*/

this.startup = function( terminal ) {

// @TODO: Make this and the shutdown function asynchronous

var info = this.api.request( 'GET', '/users/' + this.username, {}, {}, false );

var history = this.api.request( 'GET', '/users/' + this.username + '/history', {}, {}, false );

var homedir = info['responseJSON']['homedir'];

if ( !homedir ) {

homedir = '/';

}

this.environment['USER'] = this.username;

this.environment['HOME'] = homedir;

this.environment['PWD'] = homedir;

terminal.prompt = this.username + '@ubuntu ' + homedir + ' $ ';

if ( history['status'] === 200 ) {

terminal.cmdHistory = history['responseJSON'];

terminal.currHistoryPos = history['responseJSON'].length;

this.historyMarker = history['responseJSON'].length;

}

};

/**

* Shutdown function

* @param {Terminal} terminal

*/

this.shutdown = function( terminal ) {

if ( this.historyMarker < terminal.cmdHistory.length ) {

this.api.request( 'PATCH', '/users/' + this.username + '/history',

{ 'history': terminal.cmdHistory.slice( this.historyMarker ) }

);

this.historyMarker = terminal.cmdHistory.length;

}

};

/**

* Execute a command given an array of arguments

* @param {string} text Arguments typed

* @param {Terminal} terminal

*/

this.execute = function( text, terminal ) {

var deferred = $.Deferred();

deferred.stdin = new IoStream();

setTimeout( $.proxy( function() {

var argv = text;

if ( typeof argv === 'string' ) {

argv = this.replaceVariables( $.splitArgs( text ) );

}

this.executeCommand( argv, terminal, deferred );

}, this ), 0 );

var promise = deferred.promise();

promise.stdin = deferred.stdin;

return promise;

};

/**

* Actually execute the command (this should be called asynchronously)

* @param {string} argv The command

* @param {Terminal} terminal

* @param {jQuery.Deferred} deferred

*/

this.executeCommand = function( argv, terminal, deferred ) {

// Check for aliases

if ( argv[0] in this.aliasCommands ) {

argv = $.merge( $.splitArgs( this.aliasCommands[argv[0]] ), argv.slice( 1 ) );

}

// Setup the file descriptors

var retval = '0',

fds = [ deferred.stdin, new IoStream(), new IoStream() ],

foundStdout = false;

foundStderr = false,

nextCmd = null,

pipeIndex = argv.indexOf( '|' );

if ( pipeIndex !== -1 ) {

foundStdout = true;

var nextArgv = argv.splice( pipeIndex, argv.length - pipeIndex );

nextArgv.shift();

if ( nextArgv.length > 0 ) {

nextCmd = this.execute( nextArgv, terminal );

fds[1].getPromise().progress( function( stream ) {

nextCmd.stdin.write( stream.read() );

} );

fds[1].getPromise().done( function( stream ) {

nextCmd.stdin.write( stream.read() );

nextCmd.stdin.close();

} );

nextCmd.progress( function( text ) {

deferred.notify( text );

} );

}

}

// Look for file description redirection

for ( var i = argv.indexOf( '>' ); i !== -1; i = argv.indexOf( '>', i + 1 ) ) {

foundStdout = true;

var path = $.realpath( argv[i + 1], this.environment['PWD'], this.environment['HOME'] );

fds[1].getPromise().done( $.proxy( function( stream ) {

var txt = stream.read();

this.api.request( 'POST', '/files' + path, '', {} ).done( $.proxy( function () {

this.api.request( 'PATCH', '/files' + path, txt, { 'Content-Type': 'text/plain' } );

}, this ) );

}, this ) );;

argv.splice( i, 2 );

}

for ( var i = argv.indexOf( '2>' ); i !== -1; i = argv.indexOf( '2>', i + 1 ) ) {

foundStderr = true;

var path = $.realpath( argv[i + 1], this.environment['PWD'], this.environment['HOME'] );

fds[2].getPromise().done( $.proxy( function( stream ) {

var txt = stream.read();

this.api.request( 'POST', '/files' + path, '', {} ).done( $.proxy( function () {

this.api.request( 'PATCH', '/files' + path, txt, { 'Content-Type': 'text/plain' } );

}, this ) );

}, this ) );;

argv.splice( i, 2 );

}

for ( var i = argv.indexOf( '<' ); i !== -1; i = argv.indexOf( '<', i + 1 ) ) {

var path = $.realpath( argv[i + 1], this.environment['PWD'], this.environment['HOME'] );

fds[0] = new IoStream();

this.api.request( 'GET', '/files' + path ).done( function( txt ) {

fds[0].write( txt );

fds[0].close();

} );

argv.splice( i, 2 );

}

// If there was no redirection, output to the terminal

if ( !foundStdout ) {

fds[1].write = function( txt ) {

deferred.notify( [txt] );

};

}

if ( !foundStderr ) {

fds[2].write = function( txt ) {

deferred.notify( [txt] );

};

}

// Try and execute the command

if ( argv[0] === 'exit' ) {

this.shutdown( terminal );

this.api.logout();

// Hopefully something here will close the window

window.open( '', '_self', '' );

window.close();

self.close();

} else if ( argv[0] === "clear" ) {

terminal.clear();

} else if ( argv[0] === "alias" ) {

for ( var i = 1; i < argv.length; ++i ) {

var splt = argv[i].split( '=', 2 );

if( splt.length != 2 ) {

continue;

}

this.aliasCommands[splt[0]] = splt[1];

}

retval = '0';

} else if ( argv[0] in WebBash['commands'] ) {

var argc = argv.length;

retval = WebBash['commands'][argv[0]]( fds, argc, argv, this.environment, terminal );

} else if ( argv[0] ) {

deferred.notify( ["error: unknown command " + argv[0]] );

retval = '127';

}

var updateFunc = $.proxy( function( retcode ) {

this.environment['?'] = retcode.toString();

terminal.prompt = this.username + '@ubuntu ' + this.environment['PWD'] + ' $ ';

deferred.resolve( retcode );

}, this );

if ( $.type( retval ) === 'object' && retval.then !== undefined ) {

retval.then( function() {

fds[0].close();

fds[1].close();

fds[2].close();

} );

if ( nextCmd === null ) {

retval.then( updateFunc );

} else {

retval.then( function() { nextCmd.then( updateFunc ); } );

}

} else {

fds[0].close();

fds[1].close();

fds[2].close();

if ( nextCmd === null ) {

updateFunc( retval );

} else {

nextCmd.then( function() { updateFunc( retval ); } );

}

}

};

/**

* Replace variables in arguments using the environment

* @private

* @param {Array.<string>} argv Arguments to process

* @return {Array.<string>} Arguments with variables replaced

*/

this.replaceVariables = function( argv ) {

for ( var i = 1; i < argv.length; ++i ) {

for (

var index = argv[i].indexOf( '$' );

index >= 0;

index = argv[i].indexOf( '$', index + 1 )

) {

if ( index !== 0 && argv[i][index - 1] === '\\' ) {

argv[i] = argv[i].substr( 0, index - 1 ) + argv[i].substr( index );

continue;

}

var envName = this.varPatt.exec( argv[i].substr( index + 1 ) )[0];

if ( envName === null ) {

continue;

}

if ( typeof this.environment[envName] === 'undefined' ) {

this.environment[envName] = '';

}

argv[i] = argv[i].substr( 0, index ) +

this.environment[envName] +

argv[i].substr( index + envName.length + 1 );

}

}

return argv;

};

}

/**

* List of commands

* @expose

* @dict

* @type {Object.<string, function(Array.<IoStream>, number, Array.<string>, Array.<string>, Terminal): number>}

*/

WebBash['commands'] = {};

window['WebBash'] = WebBash;