Merge branch 'feature/the-actual-tomato-sauce' into develop

1 files changed, 129 insertions, 0 deletions

diff --git a/lib/tomato_sauce.js b/lib/tomato_sauce.js
new file mode 100644
index 0000000..0ff087a
--- /dev/null
+++ b/lib/tomato_sauce.js
@@ -0,0 +1,129 @@
+'use strict';
+
+const Net = require('net');
+const EventEmitter = require('events');
+
+const Util = require('./util');
+
+// Interpret as Command Sequences.
+const kEscape = new Buffer([0xFF, 0xF4, 0XFF, 0xFD, 0x06]); // IAC IP IAC DO TIMING_MARK
+const kNAWSRequest = new Buffer([0xFF, 0xFD, 0X1F]); // IAC DO NAWS
+const kNAWSResponse = new Buffer([0xFF, 0xFB, 0X1F, 0xFF, 0xFA, 0X1F]); // IAC WILL NAWS IAC SB NAWS
+
+// Main tomato sauce class. Properties:
+// * screens <TomatoSauce.IScreen[]>
+// * renderers <TomatoSauce.IRenderer[]>
+// * port <int>
+// * frequency <int>
+// * modulation <int>
+//
+// The main entry point is the #run() function.
+//
+// It emits a listening event that contains the server information on
+// the `server` key inside the `data` property of the event.
+//
+// It also emits an error event that contains the error information on
+// the `error` key inside the `data` property of the event.
+const TomatoSauce = class TomatoSauce extends EventEmitter {
+
+  constructor (config) {
+    super();
+
+    this.screens = [];
+    this.renderers = [];
+
+    Object.assign(this, config || {});
+  }
+
+  // Here's where things get started.
+  run () {
+    this._startServer();
+    this._bindEvents();
+  }
+
+  // Creates a socket, server based on the configuration. Emits the
+  // listening event when ready.
+  _startServer () {
+    const server = Net.createServer();
+    this.server = server;
+    server.listen(this.port, function () {
+      this.emit('listening', {
+        data: {
+          server: server
+        }
+      });
+    }.bind(this));
+  }
+
+  _bindEvents () {
+    // Send the error event all the way up.
+    this.server.on('error', function (err) {
+      this.emit('error', {
+        data: {
+          error: err
+        }
+      });
+    }.bind(this));
+
+    // Send the error event all the way up.
+    this.server.on('connection', function (socket) {
+      this._renderScreen(socket);
+    }.bind(this));
+  }
+
+  // Obtains viewport size, and initializes a random screen with a random
+  // renderer, setting the required interval to draw.
+  _renderScreen (socket) {
+    let connectionData = {
+      width: null,
+      height: null,
+      modulation: 0,
+      screen: this._getScreen(),
+      renderer: this._getRenderer(),
+      socket: socket
+    };
+    let interval = null;
+
+    socket.write(kNAWSRequest);
+
+    socket.on('data', function (data) {
+      if (data.slice(0, 6).compare(kNAWSResponse) === 0) {
+        connectionData.width = Util.parse16BitBuffer(data.slice(6, 8));
+        connectionData.height = Util.parse16BitBuffer(data.slice(8, 10));
+
+        socket.write('\x1B[2J'); // Clear the Screen (CSI 2 J)
+        interval = setInterval(this._writeMessage.bind(this, connectionData), this.frequency);
+      }
+
+      if (data.compare(kEscape) === 0) {
+        socket.write('\n');
+        clearInterval(interval);
+        socket.end();
+      }
+    }.bind(this));
+  }
+
+  // Resets the cursor, gets a frame and sends it to the socket.
+  _writeMessage (connectionData) {
+    let payload = connectionData.screen(connectionData.modulation, connectionData.width, connectionData.height, connectionData.renderer);
+    let message = `\x1B[1;1H${payload}`; // reset cursor position before payload
+
+    connectionData.modulation = (connectionData.modulation + this.modulation) % 256;
+    connectionData.socket.write(message);
+  }
+
+  _getScreen () {
+    return Util.pickRandom(this.screens);
+  }
+
+  _getRenderer () {
+    return Util.pickRandom(this.renderers);
+  }
+};
+
+// Defaults.
+TomatoSauce.prototype.port = 9999;
+TomatoSauce.prototype.frequency = 333;
+TomatoSauce.prototype.modulation = 5;
+
+module.exports = TomatoSauce;