adding label 15 takeoff decoding

lib/plugins/Label_15.test.ts

@@ -19,7 +19,7 @@ describe('Label_15', () => {
         });
     });
 
-    test('decodes short variant missing ???', () => {
+    test('decodes short variant missing unkown', () => {
         const text = '(2N38448W 77216--- 28 20  7(Z'
         const decodeResult = plugin.decode({ text: text });
 
@@ -65,16 +65,48 @@ describe('Label_15', () => {
         expect(decodeResult.remaining.text).toBe('--- 42');
     });
 
-    test('decodes long variant', () => {
+    test('decodes off variant no unkown', () => {
         const text = '(2N39018W 77284OFF11112418101313--------(Z'
         const decodeResult = plugin.decode({ text: text });
 
         expect(decodeResult.decoded).toBe(true);
         expect(decodeResult.decoder.decodeLevel).toBe('partial');
-        expect(decodeResult.formatted.items.length).toBe(1);
+        expect(decodeResult.formatted.items.length).toBe(2);
         expect(decodeResult.formatted.items[0].label).toBe('Aircraft Position');
         expect(decodeResult.formatted.items[0].value).toBe('39.030 N, 77.473 W');
-        expect(decodeResult.remaining.text).toBe('OFF11112418101313--------');
+        expect(decodeResult.formatted.items[1].label).toBe('Takeoff Time');
+        expect(decodeResult.formatted.items[1].value).toBe('2024-11-11T18:10:00Z');
+        expect(decodeResult.remaining.text).toBe('1313--------');
+    });
+
+    test('decodes off variant no date and unknown', () => {
+        // https://app.airframes.io/messages/3593342701
+        const text = '(2N42589W 83520OFF------13280606--------(Z'
+        const decodeResult = plugin.decode({ text: text });
+
+        expect(decodeResult.decoded).toBe(true);
+        expect(decodeResult.decoder.decodeLevel).toBe('partial');
+        expect(decodeResult.formatted.items.length).toBe(2);
+        expect(decodeResult.formatted.items[0].label).toBe('Aircraft Position');
+        expect(decodeResult.formatted.items[0].value).toBe('42.982 N, 83.867 W');
+        expect(decodeResult.formatted.items[1].label).toBe('Takeoff Time');
+        expect(decodeResult.formatted.items[1].value).toBe('13:28:00');
+        expect(decodeResult.remaining.text).toBe('0606--------');
+    });
+
+    test('decodes off variant all fields', () => {
+        // https://app.airframes.io/messages/3603048708
+        const text = '(2N39042W 77308OFF1311240327B1818 015(Z'
+        const decodeResult = plugin.decode({ text: text });
+
+        expect(decodeResult.decoded).toBe(true);
+        expect(decodeResult.decoder.decodeLevel).toBe('partial');
+        expect(decodeResult.formatted.items.length).toBe(2);
+        expect(decodeResult.formatted.items[0].label).toBe('Aircraft Position');
+        expect(decodeResult.formatted.items[0].value).toBe('39.070 N, 77.513 W');
+        expect(decodeResult.formatted.items[1].label).toBe('Takeoff Time');
+        expect(decodeResult.formatted.items[1].value).toBe('2024-11-13T03:27:00Z');
+        expect(decodeResult.remaining.text).toBe('B1818 015');
     });
 
     test('does not decode Label 15 <invalid>', () => {

lib/plugins/Label_15.ts

@@ -1,3 +1,4 @@
+import { DateTimeUtils } from '../DateTimeUtils';
 import { DecoderPlugin } from '../DecoderPlugin';
 import { DecodeResult, Message, Options } from '../DecoderPluginInterface';
 import { CoordinateUtils } from '../utils/coordinate_utils';
@@ -30,8 +31,19 @@ export class Label_15 extends DecoderPlugin {
           ResultFormatter.altitude(decodeResult, 100 * Number(alt));
         }
         ResultFormatter.temperature(decodeResult, between.substring(22).replaceAll(" ", "0"));
-      } else { // long variant
-        ResultFormatter.unknown(decodeResult, between.substring(13));
+      } else if(between.substring(13,16) === 'OFF') { // off variant
+        const ddmmyy = between.substring(16, 22);
+        const hhmm = between.substring(22, 26);
+        if(ddmmyy != '------') {
+          const mmddyy = ddmmyy.substring(2, 4) + ddmmyy.substring(0, 2) + ddmmyy.substring(4);
+          console.log(`Decoder: mmddyy: ${mmddyy}, hhmm: ${hhmm}`);
+          ResultFormatter.off(decodeResult, DateTimeUtils.convertDateTimeToEpoch(hhmm+'00', mmddyy), 'epoch');
+        } else {
+          ResultFormatter.off(decodeResult, DateTimeUtils.convertHHMMSSToTod(hhmm), 'tod');
+        }
+        ResultFormatter.unknown(decodeResult, between.substring(26));
+      } else {
+        ResultFormatter.unknown(decodeResult, between.substring(26));
       }
     } else {
       if (options.debug) {

lib/utils/result_formatter.ts

@@ -284,14 +284,24 @@ export class ResultFormatter {
         });
     }
 
-    static off(decodeResult: DecodeResult, time: number) {
-        decodeResult.raw.off_time = time;
-        decodeResult.formatted.items.push({
-            type: 'time_of_day',
-            code: 'OFF',
-            label: 'Takeoff Time',
-            value: DateTimeUtils.timestampToString(time, 'tod'),
-        });
+    static off(decodeResult: DecodeResult, time: number, type: 'tod' | 'epoch' = 'tod') {
+        if (type === 'tod') {
+            decodeResult.raw.off_time = time;
+            decodeResult.formatted.items.push({
+                type: 'time_of_day',
+                code: 'OFF',
+                label: 'Takeoff Time',
+                value: DateTimeUtils.timestampToString(time, 'tod'),
+            });
+        } else {
+            decodeResult.raw.off_date = time;
+            decodeResult.formatted.items.push({
+                type: 'epoch',
+                code: 'OFF',
+                label: 'Takeoff Time',
+                value: DateTimeUtils.timestampToString(time, 'epoch'),
+            });
+        }
     }
 
     static on(decodeResult: DecodeResult, time: number) {