Refactor G-code sender

src/app/lib/gcode-sender.js

@@ -2,20 +2,45 @@ import _ from 'lodash';
 import events from 'events';
 import * as parser from 'gcode-parser';
 
+export const STREAMING_PROTOCOL_SEND_RESPONSE = 0;
+export const STREAMING_PROTOCOL_CHAR_COUNTING = 1;
+
+const DEFAULT_STREAMING_BUFFER_SIZE = 127;
+
 class GCodeSender extends events.EventEmitter {
     name = '';
     gcode = '';
     remain = [];
     sent = [];
+    streamingBufferSize = DEFAULT_STREAMING_BUFFER_SIZE;
+    streamingProtocol = STREAMING_PROTOCOL_SEND_RESPONSE;
+    streamingQueue = []; // used in char-counting streaming protocol
     total = 0;
     createdTime = 0;
     startedTime = 0;
     finishedTime = 0;
     changed = false;
 
-    constructor() {
+    // @param {number} streamingProtocol The streaming protocol. 0 for send-response (default), 1 for character-counting.
+    // @param {number} streamingBufferSize The buffer size used in character-counting streaming protocol. Defaults to 127.
+    constructor(options) {
         super();
 
+        const {
+            streamingProtocol = STREAMING_PROTOCOL_SEND_RESPONSE,
+            streamingBufferSize = DEFAULT_STREAMING_BUFFER_SIZE
+        } = { ...options };
+
+        if (_.includes([
+            STREAMING_PROTOCOL_SEND_RESPONSE,
+            STREAMING_PROTOCOL_CHAR_COUNTING
+        ], streamingProtocol)) {
+            this.streamingProtocol = streamingProtocol;
+        }
+        if (_.isNumber(streamingBufferSize) && streamingBufferSize > 0) {
+            this.streamingBufferSize = streamingBufferSize;
+        }
+
         this.on('change', () => {
             this.changed = true;
         });
@@ -27,6 +52,10 @@ class GCodeSender extends events.EventEmitter {
             remain: this.remain.length,
             sent: this.sent.length,
             total: this.total,
+            streaming: {
+                proto: this.streamingProtocol,
+                queue: this.streamingQueue.join('').length
+            },
             createdTime: this.createdTime,
             startedTime: this.startedTime,
             finishedTime: this.finishedTime
@@ -44,10 +73,11 @@ class GCodeSender extends events.EventEmitter {
             this.remain = _(results)
                 .map('words')
                 .map((words) => {
-                    return _.map(words, (word) => word[0] + word[1]).join(' ');
+                    return _.map(words, (word) => word[0] + word[1]).join(' ') + '\n';
                 })
                 .value();
             this.sent = [];
+            this.streamingQueue = [];
             this.total = this.remain.length;
             this.createdTime = new Date().getTime();
             this.startedTime = 0;
@@ -64,6 +94,7 @@ class GCodeSender extends events.EventEmitter {
         this.gcode = '';
         this.remain = [];
         this.sent = [];
+        this.streamingQueue = [];
         this.total = 0;
         this.createdTime = 0;
         this.startedTime = 0;
@@ -73,39 +104,67 @@ class GCodeSender extends events.EventEmitter {
         this.emit('change');
     }
     next() {
-        let remainLength = this.remain.length;
-        let sentLength = this.sent.length;
-
-        if (remainLength === 0 && sentLength === 0) {
-            return false;
+        if (this.remain.length === 0 && this.sent.length === 0) {
+            return;
         }
-        if (remainLength === 0) {
-            this.finishedTime = new Date().getTime();
-            this.emit('done', { time: this.finishedTime });
-            this.emit('change');
-            return false;
-        }
-        if (sentLength === 0) {
+        if (this.remain.length > 0 && this.sent.length === 0) {
             this.startedTime = new Date().getTime();
             this.emit('start', { time: this.startedTime });
             this.emit('change');
         }
 
-        let gcode = this.remain.shift();
-        this.sent.push(gcode);
-        this.emit('change');
-        this.emit('progress', { gcode: gcode });
+        const streamingMethod = {
+            [STREAMING_PROTOCOL_SEND_RESPONSE]: () => {
+                while (this.remain.length > 0) {
+                    const gcode = this.remain.shift();
+                    this.sent.push(gcode);
+                    this.emit('change');
 
-        // Continue to the next line if empty
-        if (!gcode) {
-            return this.next();
-        }
+                    if (gcode.trim().length > 0) {
+                        this.emit('gcode', gcode);
+                        break;
+                    }
 
-        return gcode;
+                    // Continue to the next line if empty
+                }
+            },
+            [STREAMING_PROTOCOL_CHAR_COUNTING]: () => {
+                this.streamingQueue.shift();
+
+                while (this.remain.length > 0) {
+                    const gcode = this.remain.shift();
+                    const streamingQueueLength = this.streamingQueue.join('').length;
+
+                    if (gcode.length + streamingQueueLength >= this.streamingBufferSize) {
+                        this.remain.unshift(gcode);
+                        break;
+                    }
+
+                    this.sent.push(gcode);
+                    this.emit('change');
+
+                    if (gcode.trim().length > 0) {
+                        this.streamingQueue.push(gcode);
+                        this.emit('gcode', gcode);
+                    }
+
+                    // Continue to the next line if empty
+                }
+            }
+        }[this.streamingProtocol];
+
+        streamingMethod && streamingMethod();
+
+        if (this.remain.length === 0) {
+            this.finishedTime = new Date().getTime();
+            this.emit('done', { time: this.finishedTime });
+            this.emit('change');
+        }
     }
     rewind() {
         this.remain = this.sent.concat(this.remain);
         this.sent = [];
+        this.streamingQueue = [];
         this.startedTime = 0;
         this.finishedTime = 0;
         this.emit('change');