Adding H1 *POS parsing (#183)

Author: makrsmark

lib/MessageDecoder.ts

@@ -49,6 +49,7 @@ export class MessageDecoder {
     this.registerPlugin(new Plugins.Label_H1_OHMA(this));
     this.registerPlugin(new Plugins.Label_H1_WRN(this));
     this.registerPlugin(new Plugins.Label_H1(this));
+    this.registerPlugin(new Plugins.Label_H1_StarPOS(this));
     this.registerPlugin(new Plugins.Label_HX(this));
     this.registerPlugin(new Plugins.Label_80(this));
     this.registerPlugin(new Plugins.Label_83(this));

lib/plugins/Label_H1_StarPOS.test.ts

@@ -0,0 +1,49 @@
+import { MessageDecoder } from '../MessageDecoder';
+import { Label_H1_StarPOS } from './Label_H1_StarPOS';
+
+describe('Label H1 *POS', () => {
+
+  let plugin: Label_H1_StarPOS;
+
+  beforeEach(() => {
+    const decoder = new MessageDecoder();
+    plugin = new Label_H1_StarPOS(decoder);
+  });
+
+  test('decodes variant 1', () => {
+
+    const text = '*POS10300950N3954W07759363312045802M5230175';
+    const decodeResult = plugin.decode({ text: text });
+
+    expect(decodeResult.decoded).toBe(true);
+    expect(decodeResult.decoder.decodeLevel).toBe('partial');
+    expect(decodeResult.message.text).toBe(text);
+    expect(decodeResult.raw.day_of_month).toBe(30);
+    expect(decodeResult.raw.month).toBe(10);
+    expect(decodeResult.raw.time_of_day).toBe(35400);
+    expect(decodeResult.raw.position.latitude).toBe(39.900000);
+    expect(decodeResult.raw.position.longitude).toBe(-77.98333333333333);
+    expect(decodeResult.raw.altitude).toBe(36331);
+    expect(decodeResult.formatted.items.length).toBe(3);
+    expect(decodeResult.formatted.items[0].label).toBe('Message Timestamp');
+    expect(decodeResult.formatted.items[0].value).toBe('09:50:00');
+    expect(decodeResult.formatted.items[1].label).toBe('Aircraft Position');
+    expect(decodeResult.formatted.items[1].value).toBe('39.900 N, 77.983 W');
+    expect(decodeResult.formatted.items[2].label).toBe('Altitude');
+    expect(decodeResult.formatted.items[2].value).toBe('36331 feet');
+    
+    expect(decodeResult.remaining.text).toBe('2045802M5230175');
+  });
+
+
+  test('does not decode <invalid>', () => {
+
+    const text = '*POS Bogus message';
+    const decodeResult = plugin.decode({ text: text });
+
+    expect(decodeResult.decoded).toBe(false);
+    expect(decodeResult.decoder.decodeLevel).toBe('none');
+    expect(decodeResult.formatted.description).toBe('Position Report');
+    expect(decodeResult.formatted.items.length).toBe(0);
+  });
+});

lib/plugins/Label_H1_StarPOS.ts

@@ -0,0 +1,49 @@
+import { DateTimeUtils } from '../DateTimeUtils';
+import { DecoderPlugin } from '../DecoderPlugin';
+import { DecodeResult, Message, Options } from '../DecoderPluginInterface';
+import { CoordinateUtils } from '../utils/coordinate_utils';
+import { ResultFormatter } from '../utils/result_formatter';
+
+export class Label_H1_StarPOS extends DecoderPlugin {
+  name = 'label-h1-star-pos';
+  qualifiers() { // eslint-disable-line class-methods-use-this
+    return {
+      labels: ['H1'],
+      preambles: ['*POS'],
+    };
+  }
+
+  decode(message: Message, options: Options = {}) : DecodeResult {
+    let decodeResult = this.defaultResult();
+    decodeResult.decoder.name = this.name;
+    decodeResult.formatted.description = 'Position Report';
+    decodeResult.message = message;
+
+    const msg = message.text;
+    // assuming fixed length until other variants found
+    if (msg.length !== 43 || !msg.startsWith('*POS')) {
+      if (options.debug) {
+        console.log(`Decoder: Unknown H1 message: ${msg}`);
+      }
+      ResultFormatter.unknown(decodeResult, msg);
+      decodeResult.decoded = false;
+      decodeResult.decoder.decodeLevel = 'none';
+      return decodeResult;
+    }
+
+    decodeResult.raw.month = Number(msg.substring(4, 6));
+    decodeResult.raw.day_of_month = Number(msg.substring(6, 8));
+    ResultFormatter.time_of_day(decodeResult, DateTimeUtils.convertHHMMSSToTod(msg.substring(8, 12) + '00'));
+    ResultFormatter.position(decodeResult, { // Deg Min, no sec
+      latitude: CoordinateUtils.getDirection(msg.substring(12,13)) * (Number(msg.substring(13, 15)) + Number(msg.substring(15, 17))/60), 
+      longitude: CoordinateUtils.getDirection(msg.substring(17,18)) * (Number(msg.substring(18, 21)) + Number(msg.substring(21, 23))/60)
+    });
+    ResultFormatter.altitude(decodeResult, Number(msg.substring(23, 28)));
+    ResultFormatter.unknown(decodeResult, msg.substring(28));
+    decodeResult.decoded = true;
+    decodeResult.decoder.decodeLevel = 'partial';
+    return decodeResult;
+  }
+}
+
+export default {};

lib/plugins/official.ts

@@ -34,10 +34,11 @@ export * from './Label_83';
 export * from './Label_8E';
 export * from './Label_B6';
 export * from './Label_ColonComma';
+export * from './Label_H1';
 export * from './Label_H1_FLR';
 export * from './Label_H1_OHMA';
+export * from './Label_H1_StarPOS';
 export * from './Label_H1_WRN';
-export * from './Label_H1';
 export * from './Label_HX';
 export * from './Label_SQ';
 export * from './Label_QR';