feat(acars): add message translator and ADS-B datalink integration

Add ACARS label translation, message classification, and field parsers
so decoded messages show human-readable descriptions instead of raw
label codes (H1, DF, _d, 5Z, etc.). Integrate translated ACARS
messages into the ADS-B aircraft detail panel and add a live message
feed to the standalone ACARS mode.

- New utils/acars_translator.py with ~50 label codes, type classifier,
  and parsers for position reports, engine data, weather, and OOOI
- Enrich messages at ingest in routes/acars.py with translation fields
- Backfill translation in /adsb/aircraft/<icao>/messages endpoint
- ADS-B dashboard: DATALINK MESSAGES section in aircraft detail panel
  with auto-refresh, color-coded type badges, and parsed field display
- Standalone ACARS mode: scrollable live message feed (max 30 cards)
- Fix default N. America ACARS frequencies to 131.550/130.025/129.125
- Unit tests covering all translator functions

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

.env.example

@@ -1,2 +1,32 @@
-# Uncomment and set to use external storage for ADS-B history
+# =============================================================================
-# PGDATA_PATH=/mnt/external/intercept/pgdata
+# INTERCEPT CONTROLLER (.env)
+# =============================================================================
+# Copy to .env and edit for your setup
+
+# Container timezone (e.g. America/New_York, Europe/London, Australia/Sydney)
+TZ=UTC
+
+# Postgres password (default: intercept)
+INTERCEPT_ADSB_DB_PASSWORD=intercept
+
+# Auto-start ADS-B when dashboard loads
+INTERCEPT_ADSB_AUTO_START=false
+
+# Share observer location across all modules
+INTERCEPT_SHARED_OBSERVER_LOCATION=true
+
+# Observer coordinates (uncomment and set to skip GPS prompt)
+# INTERCEPT_DEFAULT_LAT=40.7128
+# INTERCEPT_DEFAULT_LON=-74.0060
+
+# =============================================================================
+# AGENT SETTINGS (for docker-compose.agent.yml on remote Pis)
+# =============================================================================
+
+# Agent identity
+AGENT_NAME=sdr-agent-1
+AGENT_PORT=8020
+
+# Controller connection (IP of the machine running docker-compose.yml)
+CONTROLLER_URL=http://192.168.1.100:5050
+AGENT_API_KEY=changeme

docker-compose.yml

@@ -29,6 +29,7 @@ services:
       # Optional: mount logs directory
       # - ./logs:/app/logs
     environment:
+      - TZ=${TZ:-UTC}
       - INTERCEPT_HOST=0.0.0.0
       - INTERCEPT_PORT=5050
       - INTERCEPT_LOG_LEVEL=INFO
@@ -78,6 +79,7 @@ services:
     volumes:
       - ./data:/app/data
     environment:
+      - TZ=${TZ:-UTC}
       - INTERCEPT_HOST=0.0.0.0
       - INTERCEPT_PORT=5050
       - INTERCEPT_LOG_LEVEL=INFO
@@ -108,6 +110,7 @@ services:
     profiles:
       - history
     environment:
+      - TZ=${TZ:-UTC}
       - POSTGRES_DB=intercept_adsb
       - POSTGRES_USER=intercept
       - POSTGRES_PASSWORD=intercept

routes/acars.py

@@ -33,10 +33,11 @@ from utils.process import register_process, unregister_process
 
 acars_bp = Blueprint('acars', __name__, url_prefix='/acars')
 
-# Default VHF ACARS frequencies (MHz) - common worldwide
+# Default VHF ACARS frequencies (MHz) - North America primary
 DEFAULT_ACARS_FREQUENCIES = [
-    '131.725',  # North America
+    '131.550',  # North America primary
-    '131.825',  # North America
+    '130.025',  # North America secondary
+    '129.125',  # North America tertiary
 ]
 
 # Message counter for statistics
@@ -120,6 +121,16 @@ def stream_acars_output(process: subprocess.Popen, is_text_mode: bool = False) -
                 data['type'] = 'acars'
                 data['timestamp'] = datetime.utcnow().isoformat() + 'Z'
 
+                # Enrich with translated label and parsed fields
+                try:
+                    from utils.acars_translator import translate_message
+                    translation = translate_message(data)
+                    data['label_description'] = translation['label_description']
+                    data['message_type'] = translation['message_type']
+                    data['parsed'] = translation['parsed']
+                except Exception:
+                    pass
+
                 # Update stats
                 acars_message_count += 1
                 acars_last_message_time = time.time()
@@ -438,7 +449,7 @@ def get_frequencies() -> Response:
     return jsonify({
         'default': DEFAULT_ACARS_FREQUENCIES,
         'regions': {
-            'north_america': ['131.725', '131.825'],
+            'north_america': ['131.550', '130.025', '129.125'],
             'europe': ['131.525', '131.725', '131.550'],
             'asia_pacific': ['131.550', '131.450'],
         }

routes/adsb.py

@@ -1189,4 +1189,17 @@ def get_aircraft_messages(icao: str):
 
     from utils.flight_correlator import get_flight_correlator
     messages = get_flight_correlator().get_messages_for_aircraft(icao=icao.upper(), callsign=callsign)
+
+    # Backfill translation on messages missing label_description
+    try:
+        from utils.acars_translator import translate_message
+        for msg in messages.get('acars', []):
+            if not msg.get('label_description'):
+                translation = translate_message(msg)
+                msg['label_description'] = translation['label_description']
+                msg['message_type'] = translation['message_type']
+                msg['parsed'] = translation['parsed']
+    except Exception:
+        pass
+
     return jsonify({'status': 'success', 'icao': icao.upper(), **messages})

static/css/modes/acars.css

@@ -89,3 +89,22 @@
     0%, 100% { opacity: 1; box-shadow: 0 0 0 0 rgba(74, 158, 255, 0.7); }
     50% { opacity: 0.6; box-shadow: 0 0 6px 3px rgba(74, 158, 255, 0.3); }
 }
+
+/* ACARS Standalone Message Feed */
+.acars-message-feed {
+    scrollbar-width: thin;
+    scrollbar-color: var(--border-color) transparent;
+}
+.acars-message-feed::-webkit-scrollbar {
+    width: 4px;
+}
+.acars-message-feed::-webkit-scrollbar-thumb {
+    background: var(--border-color);
+    border-radius: 2px;
+}
+.acars-feed-card {
+    transition: background 0.15s;
+}
+.acars-feed-card:hover {
+    background: rgba(74, 158, 255, 0.05);
+}

templates/adsb_dashboard.html

@@ -2891,12 +2891,130 @@ sudo make install</code>
                         <div class="telemetry-label">Range</div>
                         <div class="telemetry-value">${ac.lat ? calculateDistanceNm(observerLocation.lat, observerLocation.lon, ac.lat, ac.lon).toFixed(1) + ' nm' : 'N/A'}</div>
                     </div>
+                </div>
+                <div id="aircraftAcarsSection" style="margin-top:12px;">
+                    <div style="font-size:10px;font-weight:600;color:var(--accent-cyan);text-transform:uppercase;letter-spacing:1px;margin-bottom:6px;border-top:1px solid var(--border-color);padding-top:8px;">Datalink Messages</div>
+                    <div id="aircraftAcarsMessages" style="font-size:10px;color:var(--text-dim);">Loading...</div>
                 </div>`;
 
             // Fetch aircraft photo if registration is available
             if (registration) {
                 fetchAircraftPhoto(registration);
             }
+
+            // Fetch ACARS messages for this aircraft
+            fetchAircraftMessages(icao);
+        }
+
+        // ACARS message refresh timer for selected aircraft
+        let acarsMessageTimer = null;
+
+        function fetchAircraftMessages(icao) {
+            // Clear previous timer
+            if (acarsMessageTimer) {
+                clearInterval(acarsMessageTimer);
+                acarsMessageTimer = null;
+            }
+
+            function doFetch() {
+                fetch('/adsb/aircraft/' + icao + '/messages')
+                    .then(r => r.json())
+                    .then(data => {
+                        const container = document.getElementById('aircraftAcarsMessages');
+                        if (!container) return;
+                        const msgs = (data.acars || []).concat(data.vdl2 || []);
+                        if (msgs.length === 0) {
+                            container.innerHTML = '<span style="color:var(--text-muted);font-style:italic;">No messages yet</span>';
+                            return;
+                        }
+                        // Sort newest first
+                        msgs.sort((a, b) => (b.timestamp || '').localeCompare(a.timestamp || ''));
+                        container.innerHTML = msgs.slice(0, 20).map(renderAcarsCard).join('');
+                    })
+                    .catch(() => {
+                        const container = document.getElementById('aircraftAcarsMessages');
+                        if (container) container.innerHTML = '<span style="color:var(--text-muted);">—</span>';
+                    });
+            }
+
+            doFetch();
+            acarsMessageTimer = setInterval(doFetch, 10000);
+        }
+
+        function getAcarsTypeBadge(type) {
+            const colors = {
+                position: '#00ff88',
+                engine_data: '#ff9500',
+                weather: '#00d4ff',
+                ats: '#ffdd00',
+                cpdlc: '#b388ff',
+                oooi: '#4fc3f7',
+                squawk: '#ff6b6b',
+                link_test: '#666',
+                handshake: '#555',
+                other: '#888',
+            };
+            const labels = {
+                position: 'POS',
+                engine_data: 'ENG',
+                weather: 'WX',
+                ats: 'ATS',
+                cpdlc: 'CPDLC',
+                oooi: 'OOOI',
+                squawk: 'SQK',
+                link_test: 'LINK',
+                handshake: 'HSHK',
+                other: 'MSG',
+            };
+            const color = colors[type] || '#888';
+            const lbl = labels[type] || 'MSG';
+            return '<span style="display:inline-block;padding:1px 5px;border-radius:3px;font-size:8px;font-weight:700;color:#000;background:' + color + ';">' + lbl + '</span>';
+        }
+
+        function renderAcarsCard(msg) {
+            const type = msg.message_type || 'other';
+            const badge = getAcarsTypeBadge(type);
+            const desc = msg.label_description || ('Label ' + (msg.label || '?'));
+            const text = msg.text || msg.msg || '';
+            const truncText = text.length > 120 ? text.substring(0, 120) + '...' : text;
+            const time = msg.timestamp ? new Date(msg.timestamp).toLocaleTimeString() : '';
+            const flight = msg.flight || '';
+
+            let parsedHtml = '';
+            if (msg.parsed) {
+                const p = msg.parsed;
+                if (type === 'position' && p.lat !== undefined) {
+                    parsedHtml = '<div style="color:var(--accent-green);margin-top:2px;">' +
+                        p.lat.toFixed(4) + ', ' + p.lon.toFixed(4) +
+                        (p.flight_level ? ' • ' + p.flight_level : '') +
+                        (p.destination ? ' → ' + p.destination : '') + '</div>';
+                } else if (type === 'engine_data') {
+                    const parts = [];
+                    Object.keys(p).forEach(k => {
+                        parts.push(k + ': ' + p[k].value);
+                    });
+                    if (parts.length) {
+                        parsedHtml = '<div style="color:var(--accent-orange,#ff9500);margin-top:2px;">' + parts.slice(0, 4).join(' | ') + '</div>';
+                    }
+                } else if (type === 'oooi' && p.origin) {
+                    parsedHtml = '<div style="color:var(--accent-cyan);margin-top:2px;">' +
+                        p.origin + ' → ' + p.destination +
+                        (p.out ? ' | OUT ' + p.out : '') +
+                        (p.off ? ' OFF ' + p.off : '') +
+                        (p.on ? ' ON ' + p.on : '') +
+                        (p['in'] ? ' IN ' + p['in'] : '') + '</div>';
+                }
+            }
+
+            return '<div style="padding:5px 0;border-bottom:1px solid rgba(255,255,255,0.05);">' +
+                '<div style="display:flex;justify-content:space-between;align-items:center;margin-bottom:2px;">' +
+                '<span>' + badge + ' <span style="color:var(--text-primary);">' + desc + '</span></span>' +
+                '<span style="color:var(--text-muted);font-size:9px;">' + time + '</span></div>' +
+                (flight ? '<div style="color:var(--accent-cyan);font-size:9px;">' + flight + '</div>' : '') +
+                parsedHtml +
+                (truncText && type !== 'link_test' && type !== 'handshake' ?
+                    '<div style="color:var(--text-dim);font-family:var(--font-mono);font-size:9px;margin-top:2px;word-break:break-all;">' + truncText + '</div>' : '') +
+                '</div>';
         }
 
         // Cache for aircraft photos to avoid repeated API calls
@@ -3647,17 +3765,21 @@ sudo make install</code>
             const flight = data.flight || 'UNKNOWN';
             const reg = data.reg || '';
             const label = data.label || '';
+            const labelDesc = data.label_description || '';
+            const msgType = data.message_type || 'other';
             const text = data.text || data.msg || '';
             const time = new Date().toLocaleTimeString();
 
+            const typeBadge = typeof getAcarsTypeBadge === 'function' ? getAcarsTypeBadge(msgType) : '';
+
             msg.innerHTML = `
                 <div style="display: flex; justify-content: space-between; margin-bottom: 2px;">
                     <span style="color: var(--accent-cyan); font-weight: bold;">${flight}</span>
                     <span style="color: var(--text-muted);">${time}</span>
                 </div>
                 ${reg ? `<div style="color: var(--text-muted); font-size: 9px;">Reg: ${reg}</div>` : ''}
-                ${label ? `<div style="color: var(--accent-green);">Label: ${label}</div>` : ''}
+                <div style="margin-top: 2px;">${typeBadge} <span style="color: var(--text-primary);">${labelDesc || (label ? 'Label: ' + label : '')}</span></div>
-                ${text ? `<div style="color: var(--text-primary); margin-top: 3px; word-break: break-word;">${text}</div>` : ''}
+                ${text && msgType !== 'link_test' && msgType !== 'handshake' ? `<div style="color: var(--text-dim); margin-top: 3px; word-break: break-word; font-size: 9px;">${text.length > 80 ? text.substring(0, 80) + '...' : text}</div>` : ''}
             `;
 
             container.insertBefore(msg, container.firstChild);

templates/partials/modes/acars.html

@@ -57,7 +57,7 @@
                 <table style="width: 100%; margin-top: 6px; font-size: 10px; border-collapse: collapse;">
                     <tr style="border-bottom: 1px solid var(--border-color);">
                         <td style="padding: 3px 4px; color: var(--text-dim);">Primary (N. America)</td>
-                        <td style="padding: 3px 4px; color: var(--text-primary); text-align: right;">131.725 / 131.825 MHz</td>
+                        <td style="padding: 3px 4px; color: var(--text-primary); text-align: right;">131.550 / 130.025 MHz</td>
                     </tr>
                     <tr style="border-bottom: 1px solid var(--border-color);">
                         <td style="padding: 3px 4px; color: var(--text-dim);">Quarter-wave length</td>
@@ -82,6 +82,14 @@
     <button class="stop-btn" id="stopAcarsBtn" onclick="stopAcarsMode()" style="display: none;">
         Stop ACARS
     </button>
+
+    <!-- Live Message Feed -->
+    <div class="section" id="acarsMessageFeedSection" style="margin-top: 15px;">
+        <h3>Message Feed</h3>
+        <div id="acarsMessageFeed" class="acars-message-feed" style="max-height: 400px; overflow-y: auto; font-size: 11px;">
+            <div style="color: var(--text-muted); font-style: italic; padding: 10px 0;">Start ACARS to see live messages</div>
+        </div>
+    </div>
 </div>
 
 <script>
@@ -89,7 +97,7 @@
     let acarsMainMsgCount = 0;
 
     const acarsMainFrequencies = {
-        'na': ['131.725', '131.825'],
+        'na': ['131.550', '130.025', '129.125'],
         'eu': ['131.525', '131.725', '131.550'],
         'ap': ['131.550', '131.450']
     };
@@ -164,9 +172,64 @@
         });
     }
 
+    function acarsMainTypeBadge(type) {
+        const colors = {
+            position: '#00ff88', engine_data: '#ff9500', weather: '#00d4ff',
+            ats: '#ffdd00', cpdlc: '#b388ff', oooi: '#4fc3f7', squawk: '#ff6b6b',
+            link_test: '#666', handshake: '#555', other: '#888'
+        };
+        const labels = {
+            position: 'POS', engine_data: 'ENG', weather: 'WX', ats: 'ATS',
+            cpdlc: 'CPDLC', oooi: 'OOOI', squawk: 'SQK', link_test: 'LINK',
+            handshake: 'HSHK', other: 'MSG'
+        };
+        const color = colors[type] || '#888';
+        const lbl = labels[type] || 'MSG';
+        return `<span style="display:inline-block;padding:1px 5px;border-radius:3px;font-size:8px;font-weight:700;color:#000;background:${color};">${lbl}</span>`;
+    }
+
+    function renderAcarsMainCard(data) {
+        const flight = data.flight || 'UNKNOWN';
+        const type = data.message_type || 'other';
+        const badge = acarsMainTypeBadge(type);
+        const desc = data.label_description || (data.label ? 'Label: ' + data.label : '');
+        const text = data.text || data.msg || '';
+        const truncText = text.length > 150 ? text.substring(0, 150) + '...' : text;
+        const time = new Date().toLocaleTimeString();
+
+        let parsedHtml = '';
+        if (data.parsed) {
+            const p = data.parsed;
+            if (type === 'position' && p.lat !== undefined) {
+                parsedHtml = `<div style="color:var(--accent-green);margin-top:2px;font-size:10px;">${p.lat.toFixed(4)}, ${p.lon.toFixed(4)}${p.flight_level ? ' &bull; ' + p.flight_level : ''}${p.destination ? ' &rarr; ' + p.destination : ''}</div>`;
+            } else if (type === 'engine_data') {
+                const parts = [];
+                Object.keys(p).forEach(k => parts.push(k + ': ' + p[k].value));
+                if (parts.length) parsedHtml = `<div style="color:#ff9500;margin-top:2px;font-size:10px;">${parts.slice(0, 4).join(' | ')}</div>`;
+            } else if (type === 'oooi' && p.origin) {
+                parsedHtml = `<div style="color:var(--accent-cyan);margin-top:2px;font-size:10px;">${p.origin} &rarr; ${p.destination}${p.out ? ' | OUT ' + p.out : ''}${p.off ? ' OFF ' + p.off : ''}${p.on ? ' ON ' + p.on : ''}${p['in'] ? ' IN ' + p['in'] : ''}</div>`;
+            }
+        }
+
+        return `<div class="acars-feed-card" style="padding:6px 8px;border-bottom:1px solid var(--border-color);animation:fadeInMsg 0.3s ease;">
+            <div style="display:flex;justify-content:space-between;align-items:center;margin-bottom:2px;">
+                <span style="color:var(--accent-cyan);font-weight:bold;">${flight}</span>
+                <span style="color:var(--text-muted);font-size:9px;">${time}</span>
+            </div>
+            <div style="margin-top:2px;">${badge} <span style="color:var(--text-primary);">${desc}</span></div>
+            ${parsedHtml}
+            ${truncText && type !== 'link_test' && type !== 'handshake' ? `<div style="color:var(--text-dim);font-family:var(--font-mono);font-size:9px;margin-top:3px;word-break:break-all;">${truncText}</div>` : ''}
+        </div>`;
+    }
+
     function startAcarsMainSSE() {
         if (acarsMainEventSource) acarsMainEventSource.close();
 
+        const feed = document.getElementById('acarsMessageFeed');
+        if (feed && feed.querySelector('[style*="font-style: italic"]')) {
+            feed.innerHTML = '';
+        }
+
         acarsMainEventSource = new EventSource('/acars/stream');
         acarsMainEventSource.onmessage = function(e) {
             try {
@@ -174,6 +237,16 @@
                 if (data.type === 'acars') {
                     acarsMainMsgCount++;
                     document.getElementById('acarsMessageCount').textContent = acarsMainMsgCount;
+
+                    // Add to message feed
+                    const feed = document.getElementById('acarsMessageFeed');
+                    if (feed) {
+                        feed.insertAdjacentHTML('afterbegin', renderAcarsMainCard(data));
+                        // Keep max 30 messages for RPi performance
+                        while (feed.children.length > 30) {
+                            feed.removeChild(feed.lastChild);
+                        }
+                    }
                 }
             } catch (err) {}
         };

tests/test_acars_translator.py

@@ -0,0 +1,265 @@
+"""Tests for ACARS message translator."""
+
+import pytest
+
+from utils.acars_translator import (
+    ACARS_LABELS,
+    translate_label,
+    classify_message_type,
+    parse_position_report,
+    parse_engine_data,
+    parse_weather_data,
+    parse_oooi,
+    translate_message,
+)
+
+
+# --- translate_label ---
+
+class TestTranslateLabel:
+    def test_known_labels(self):
+        assert translate_label('H1') == 'Position report (HF data link)'
+        assert translate_label('DF') == 'Engine data / DFDR'
+        assert translate_label('_d') == 'Demand mode (link test)'
+        assert translate_label('5Z') == 'OOOI (gate times)'
+        assert translate_label('B9') == 'ATC message'
+        assert translate_label('SQ') == 'Squawk assignment'
+
+    def test_unknown_label(self):
+        assert translate_label('ZZ') == 'Label ZZ'
+
+    def test_empty_label(self):
+        assert translate_label('') == 'Unknown label'
+
+    def test_none_label(self):
+        assert translate_label(None) == 'Unknown label'
+
+    def test_q_prefix_unknown(self):
+        """Q-prefix labels not in table should get generic link management desc."""
+        assert 'Link management' in translate_label('QZ')
+
+    def test_whitespace_stripped(self):
+        assert translate_label(' H1 ') == 'Position report (HF data link)'
+
+
+# --- classify_message_type ---
+
+class TestClassifyMessageType:
+    def test_h1_is_position(self):
+        assert classify_message_type('H1') == 'position'
+
+    def test_df_is_engine_data(self):
+        assert classify_message_type('DF') == 'engine_data'
+
+    def test_h2_is_weather(self):
+        assert classify_message_type('H2') == 'weather'
+
+    def test_b9_is_ats(self):
+        assert classify_message_type('B9') == 'ats'
+
+    def test_5z_is_oooi(self):
+        assert classify_message_type('5Z') == 'oooi'
+
+    def test_sq_is_squawk(self):
+        assert classify_message_type('SQ') == 'squawk'
+
+    def test_underscore_d_is_link_test(self):
+        assert classify_message_type('_d') == 'link_test'
+
+    def test_q0_is_link_test(self):
+        assert classify_message_type('Q0') == 'link_test'
+
+    def test_aa_is_cpdlc(self):
+        assert classify_message_type('AA') == 'cpdlc'
+
+    def test_unknown_is_other(self):
+        assert classify_message_type('ZZ') == 'other'
+
+    def test_none_is_other(self):
+        assert classify_message_type(None) == 'other'
+
+    def test_text_with_bpos_override(self):
+        """H1 with #M1BPOS text should be position."""
+        assert classify_message_type('H1', '#M1BPOSN42411W086034') == 'position'
+
+
+# --- parse_position_report ---
+
+class TestParsePositionReport:
+    def test_real_h1_bpos(self):
+        text = '#M1BPOSN42411W086034,CSG,070852,340,N42441W087074,DTW,0757,224A8C'
+        result = parse_position_report(text)
+        assert result is not None
+        assert result['lat'] > 42
+        assert result['lon'] < -86
+        assert result['waypoint'] == 'CSG'
+        assert result['flight_level'] == 'FL340'
+        assert result['destination'] == 'DTW'
+
+    def test_none_text(self):
+        assert parse_position_report(None) is None
+
+    def test_empty_text(self):
+        assert parse_position_report('') is None
+
+    def test_no_bpos_data(self):
+        assert parse_position_report('SOME RANDOM TEXT') is None
+
+    def test_temperature_field(self):
+        text = '#M1BPOSN42411W086034,CSG,070852,340,N42441W087074,DTW,0757/TSM045'
+        result = parse_position_report(text)
+        assert result is not None
+        assert result.get('temperature') == '-045 C'
+
+    def test_southern_hemisphere(self):
+        text = '#M1BPOSS33500E018200,CPT,120000,350,S33500E018200,CPT,1230,ABC123'
+        result = parse_position_report(text)
+        assert result is not None
+        assert result['lat'] < 0  # South
+
+
+# --- parse_engine_data ---
+
+class TestParseEngineData:
+    def test_real_dfdr_message(self):
+        text = '#DFB SM/0 AC0/85.2 AC1/84.9 FL/350 FU/12450 ES/15'
+        result = parse_engine_data(text)
+        assert result is not None
+        assert 'AC0' in result
+        assert result['AC0']['value'] == '85.2'
+        assert 'FL' in result
+        assert result['FL']['value'] == '350'
+
+    def test_none_text(self):
+        assert parse_engine_data(None) is None
+
+    def test_empty_text(self):
+        assert parse_engine_data('') is None
+
+    def test_no_engine_keys(self):
+        assert parse_engine_data('HELLO WORLD') is None
+
+    def test_n1_n2_values(self):
+        text = 'N1/92.3 N2/88.1 EGT/425'
+        result = parse_engine_data(text)
+        assert result is not None
+        assert result['N1']['value'] == '92.3'
+        assert result['N2']['value'] == '88.1'
+        assert result['EGT']['value'] == '425'
+
+
+# --- parse_weather_data ---
+
+class TestParseWeatherData:
+    def test_wind_data(self):
+        text = 'WND270015 KJFK VIS10'
+        result = parse_weather_data(text)
+        assert result is not None
+        assert result['wind_dir'] == '270 deg'
+        assert result['wind_speed'] == '015 kts'
+
+    def test_airports(self):
+        text = '/WX KJFK KLAX TMP24'
+        result = parse_weather_data(text)
+        assert result is not None
+        assert 'KJFK' in result['airports']
+        assert 'KLAX' in result['airports']
+
+    def test_none_text(self):
+        assert parse_weather_data(None) is None
+
+    def test_empty_text(self):
+        assert parse_weather_data('') is None
+
+
+# --- parse_oooi ---
+
+class TestParseOooi:
+    def test_full_oooi(self):
+        text = 'KJFK KLAX 1423 1435 1812 1824'
+        result = parse_oooi(text)
+        assert result is not None
+        assert result['origin'] == 'KJFK'
+        assert result['destination'] == 'KLAX'
+        assert result['out'] == '1423'
+        assert result['off'] == '1435'
+        assert result['on'] == '1812'
+        assert result['in'] == '1824'
+
+    def test_partial_oooi(self):
+        text = 'KJFK KLAX 1423 1435'
+        result = parse_oooi(text)
+        assert result is not None
+        assert result['origin'] == 'KJFK'
+        assert result['destination'] == 'KLAX'
+
+    def test_none_text(self):
+        assert parse_oooi(None) is None
+
+    def test_empty_text(self):
+        assert parse_oooi('') is None
+
+
+# --- translate_message (integration) ---
+
+class TestTranslateMessage:
+    def test_h1_position(self):
+        msg = {
+            'label': 'H1',
+            'text': '#M1BPOSN42411W086034,CSG,070852,340,N42441W087074,DTW,0757,224A8C',
+        }
+        result = translate_message(msg)
+        assert result['label_description'] == 'Position report (HF data link)'
+        assert result['message_type'] == 'position'
+        assert result['parsed'] is not None
+        assert 'lat' in result['parsed']
+
+    def test_df_engine(self):
+        msg = {
+            'label': 'DF',
+            'text': '#DFB SM/0 AC0/85.2 AC1/84.9 FL/350',
+        }
+        result = translate_message(msg)
+        assert result['message_type'] == 'engine_data'
+        assert result['parsed'] is not None
+        assert 'AC0' in result['parsed']
+
+    def test_underscore_d_handshake(self):
+        msg = {'label': '_d', 'text': ''}
+        result = translate_message(msg)
+        assert result['label_description'] == 'Demand mode (link test)'
+        assert result['message_type'] in ('link_test', 'handshake')
+
+    def test_unknown_label(self):
+        msg = {'label': 'ZZ', 'text': 'SOME DATA'}
+        result = translate_message(msg)
+        assert result['label_description'] == 'Label ZZ'
+        assert result['message_type'] == 'other'
+        assert result['parsed'] is None
+
+    def test_missing_fields(self):
+        """Handles messages with no label or text gracefully."""
+        result = translate_message({})
+        assert result['label_description'] == 'Unknown label'
+        assert result['message_type'] == 'other'
+        assert result['parsed'] is None
+
+    def test_msg_field_fallback(self):
+        """Uses 'msg' field when 'text' is missing."""
+        msg = {
+            'label': 'DF',
+            'msg': '#DFB N1/92.3 N2/88.1',
+        }
+        result = translate_message(msg)
+        assert result['parsed'] is not None
+        assert 'N1' in result['parsed']
+
+    def test_5z_oooi(self):
+        msg = {
+            'label': '5Z',
+            'text': 'KJFK KLAX 1423 1435 1812 1824',
+        }
+        result = translate_message(msg)
+        assert result['message_type'] == 'oooi'
+        assert result['parsed'] is not None
+        assert result['parsed']['origin'] == 'KJFK'

utils/acars_translator.py

@@ -0,0 +1,374 @@
+"""ACARS message translator — label lookup, classification, and field parsers."""
+
+from __future__ import annotations
+
+import re
+
+# Common ACARS label codes → human-readable descriptions
+# Sources: ARINC 618, ARINC 620, airline implementations
+ACARS_LABELS: dict[str, str] = {
+    # Position & navigation
+    'H1': 'Position report (HF data link)',
+    'H2': 'Weather report',
+    '5Z': 'OOOI (gate times)',
+    '15': 'Departure report',
+    '16': 'Arrival report',
+    '20': 'Position report',
+    '22': 'Fuel report',
+    '2Z': 'Off-gate report',
+    '30': 'Progress report',
+    '44': 'Weather request',
+    '80': 'Free text (3-char header)',
+    '83': 'Free text',
+    '8E': 'ATIS request',
+
+    # Engine & performance
+    'DF': 'Engine data / DFDR',
+    'D3': 'Engine exceedance',
+    'D6': 'Engine trend data',
+
+    # ATS / air traffic services
+    'B1': 'ATC request',
+    'B2': 'ATC clearance',
+    'B3': 'ATC comm test',
+    'B6': 'ATC departure clearance',
+    'B9': 'ATC message',
+    'BA': 'ATC advisory',
+    'BB': 'ATC response',
+
+    # CPDLC (Controller-Pilot Data Link Communications)
+    'AA': 'CPDLC message',
+    'AB': 'CPDLC response',
+    'A0': 'CPDLC uplink',
+    'A1': 'CPDLC downlink',
+    'A2': 'CPDLC connection request',
+    'A3': 'CPDLC logon/logoff',
+    'A6': 'CPDLC message',
+    'A7': 'CPDLC response',
+    'AT': 'CPDLC transfer',
+
+    # Handshake & link management
+    '_d': 'Demand mode (link test)',
+    'Q0': 'Link test',
+    'QA': 'Link test reply',
+    'QB': 'Acknowledgement',
+    'QC': 'Link request',
+    'QD': 'Link accept',
+    'QE': 'Link reject',
+    'QF': 'Squitter / heartbeat',
+    'QG': 'Abort',
+    'QH': 'Version request',
+    'QK': 'Mode change',
+    'QM': 'Link verification',
+    'QN': 'Media advisory',
+    'QP': 'Polling',
+    'QQ': 'Status',
+    'QR': 'General response',
+    'QS': 'System table request',
+    'QT': 'System table',
+    'QX': 'Frequency change',
+
+    # Squawk & surveillance
+    'SQ': 'Squawk assignment',
+    'SA': 'Surveillance data',
+    'S1': 'ADS-C report',
+
+    # Airline operations
+    'C1': 'Crew scheduling',
+    'C2': 'Crew response',
+    'C3': 'Crew message',
+    'C4': 'Crew query',
+    '10': 'Delay message',
+    '12': 'Clearance request',
+    '17': 'Cargo/load data',
+    '4T': 'TWIP (terminal weather)',
+    '4X': 'Connectivity test',
+    '50': 'Weather observation',
+    '51': 'METAR/TAF request',
+    '52': 'METAR/TAF response',
+    '54': 'SIGMET / AIRMET',
+    '70': 'Maintenance report',
+    '7A': 'Fault message',
+    '7B': 'Fault clear',
+    'F3': 'Flight plan',
+    'F5': 'Flight plan amendment',
+    'F6': 'Route request',
+    'F7': 'Route clearance',
+    'RA': 'ATIS report',
+    'RB': 'ATIS request',
+}
+
+# Message type classification for UI colour coding
+MESSAGE_TYPES = {
+    'position', 'engine_data', 'weather', 'ats', 'handshake',
+    'oooi', 'squawk', 'link_test', 'cpdlc', 'other',
+}
+
+
+def translate_label(label: str | None) -> str:
+    """Return human-readable description for an ACARS label code."""
+    if not label:
+        return 'Unknown label'
+    label = label.strip()
+    if label in ACARS_LABELS:
+        return ACARS_LABELS[label]
+    # Check for Q-prefix group
+    if len(label) == 2 and label.startswith('Q'):
+        return f'Link management ({label})'
+    return f'Label {label}'
+
+
+def classify_message_type(label: str | None, text: str | None = None) -> str:
+    """Classify an ACARS message into a canonical type for UI display."""
+    if not label:
+        return 'other'
+    label = label.strip()
+
+    # Position reports
+    if label in ('H1', '20', '15', '16', '30', 'S1'):
+        return 'position'
+    if label == 'H1' or (text and '#M1BPOS' in text):
+        return 'position'
+
+    # Engine / DFDR data
+    if label in ('DF', 'D3', 'D6'):
+        return 'engine_data'
+
+    # Weather
+    if label in ('H2', '44', '50', '51', '52', '54', '4T'):
+        return 'weather'
+
+    # ATS / ATC
+    if label.startswith('B') and len(label) == 2:
+        return 'ats'
+
+    # CPDLC
+    if label in ('AA', 'AB', 'A0', 'A1', 'A2', 'A3', 'A6', 'A7', 'AT'):
+        return 'cpdlc'
+
+    # OOOI (Out/Off/On/In gate times)
+    if label in ('5Z', '2Z'):
+        return 'oooi'
+
+    # Squawk
+    if label in ('SQ', 'SA'):
+        return 'squawk'
+
+    # Link test / handshake
+    if label in ('_d', 'Q0', 'QA', 'QB', 'QC', 'QD', 'QE', 'QF', 'QG',
+                 'QH', 'QK', 'QM', 'QN', 'QP', 'QQ', 'QR', 'QS', 'QT', 'QX',
+                 '4X'):
+        return 'link_test'
+
+    # Handshake (_d is demand mode)
+    if label == '_d':
+        return 'handshake'
+
+    return 'other'
+
+
+def parse_position_report(text: str | None) -> dict | None:
+    """Parse H1 / #M1BPOS position report fields.
+
+    Example format:
+        #M1BPOSN42411W086034,CSG,070852,340,N42441W087074,DTW,0757,224A8C
+        Lat/Lon: N42411W086034 (N42.411 W086.034)
+        Waypoint: CSG
+        Time: 070852Z
+        FL: 340
+        Next waypoint coords, destination, ETA
+    """
+    if not text:
+        return None
+
+    result: dict = {}
+
+    # Look for BPOS block
+    bpos_match = re.search(
+        r'#M\d[A-Z]*POS'
+        r'([NS])(\d{2,5})([EW])(\d{3,6})'
+        r',([^,]*),(\d{4,6})'
+        r',(\d{2,3})'
+        r'(?:,([NS]\d{2,5}[EW]\d{3,6}))?'
+        r'(?:,([A-Z]{3,4}))?',
+        text
+    )
+    if bpos_match:
+        lat_dir, lat_val, lon_dir, lon_val = bpos_match.group(1, 2, 3, 4)
+        # Convert to decimal degrees
+        if len(lat_val) >= 4:
+            lat_deg = int(lat_val[:2])
+            lat_min = int(lat_val[2:]) / (10 ** (len(lat_val) - 2)) * 60
+            lat = lat_deg + lat_min / 60
+        else:
+            lat = float(lat_val)
+        if lat_dir == 'S':
+            lat = -lat
+
+        if len(lon_val) >= 5:
+            lon_deg = int(lon_val[:3])
+            lon_min = int(lon_val[3:]) / (10 ** (len(lon_val) - 3)) * 60
+            lon = lon_deg + lon_min / 60
+        else:
+            lon = float(lon_val)
+        if lon_dir == 'W':
+            lon = -lon
+
+        result['lat'] = round(lat, 4)
+        result['lon'] = round(lon, 4)
+        result['waypoint'] = bpos_match.group(5).strip() if bpos_match.group(5) else None
+        result['time'] = bpos_match.group(6)
+        result['flight_level'] = f"FL{bpos_match.group(7)}"
+        if bpos_match.group(9):
+            result['destination'] = bpos_match.group(9)
+
+    # Look for temperature (e.g., /TS-045 or M045)
+    temp_match = re.search(r'/TS([MP]?)(\d{2,3})', text)
+    if temp_match:
+        sign = '-' if temp_match.group(1) == 'M' else ''
+        result['temperature'] = f"{sign}{temp_match.group(2)} C"
+
+    return result if result else None
+
+
+def parse_engine_data(text: str | None) -> dict | None:
+    """Parse DF (engine/DFDR) messages.
+
+    Common format: #DFB followed by KEY/VALUE pairs.
+    Keys: SM (source mode), AC0/AC1 (engine 1/2 N2), FL (flight level),
+          FU (fuel used), ES (EGT spread), BA (bleed air), CO (config), AO (auto)
+    """
+    if not text:
+        return None
+
+    result: dict = {}
+    engine_keys = {
+        'SM': 'Source mode',
+        'AC0': 'Eng 1 N2 (%)',
+        'AC1': 'Eng 2 N2 (%)',
+        'FL': 'Flight level',
+        'FU': 'Fuel used (lbs)',
+        'ES': 'EGT spread',
+        'BA': 'Bleed air',
+        'CO': 'Config',
+        'AO': 'Auto',
+        'EGT': 'Exhaust gas temp',
+        'OIT': 'Oil temp',
+        'OIP': 'Oil pressure',
+        'N1': 'N1 (%)',
+        'N2': 'N2 (%)',
+        'FF': 'Fuel flow',
+        'VIB': 'Vibration',
+    }
+
+    # Match KEY/VALUE or KEY VALUE patterns
+    for key, desc in engine_keys.items():
+        pattern = rf'\b{re.escape(key)}[/: ]?\s*([+-]?\d+\.?\d*)'
+        m = re.search(pattern, text)
+        if m:
+            result[key] = {'value': m.group(1), 'description': desc}
+
+    return result if result else None
+
+
+def parse_weather_data(text: str | None) -> dict | None:
+    """Parse weather report fields (/WX blocks, METAR-like data)."""
+    if not text:
+        return None
+
+    result: dict = {}
+
+    # Wind: direction/speed (e.g., 270/15 or WND270015)
+    wind_match = re.search(r'(?:WND|WIND)\s*(\d{3})[/ ]?(\d{2,3})', text)
+    if wind_match:
+        result['wind_dir'] = f"{wind_match.group(1)} deg"
+        result['wind_speed'] = f"{wind_match.group(2)} kts"
+
+    # Airport codes (3-4 letter ICAO)
+    airports = re.findall(r'\b([A-Z]{3,4})\b', text)
+    if airports:
+        result['airports'] = list(dict.fromkeys(airports))[:4]
+
+    # Temperature (e.g., T24/D18, TMP24, TEMP -5)
+    temp_match = re.search(r'(?:TMP|TEMP|T)\s*([MP+-]?\d{1,3})', text)
+    if temp_match:
+        val = temp_match.group(1).replace('M', '-').replace('P', '')
+        result['temperature'] = f"{val} C"
+
+    # Visibility
+    vis_match = re.search(r'VIS\s*(\d+(?:\.\d+)?)', text)
+    if vis_match:
+        result['visibility'] = f"{vis_match.group(1)} SM"
+
+    return result if result else None
+
+
+def parse_oooi(text: str | None) -> dict | None:
+    """Parse 5Z OOOI (Out/Off/On/In) gate time messages.
+
+    Typical format: origin destination OUT OFF ON IN
+    e.g., KJFK KLAX 1423 1435 1812 1824
+    """
+    if not text:
+        return None
+
+    result: dict = {}
+
+    # Try to find airport pair + 4 time blocks
+    oooi_match = re.search(
+        r'([A-Z]{3,4})\s+([A-Z]{3,4})\s+(\d{4})\s+(\d{4})\s+(\d{4})\s+(\d{4})',
+        text
+    )
+    if oooi_match:
+        result['origin'] = oooi_match.group(1)
+        result['destination'] = oooi_match.group(2)
+        result['out'] = oooi_match.group(3)
+        result['off'] = oooi_match.group(4)
+        result['on'] = oooi_match.group(5)
+        result['in'] = oooi_match.group(6)
+        return result
+
+    # Try partial (just origin/destination and some times)
+    partial = re.search(r'([A-Z]{3,4})\s+([A-Z]{3,4})', text)
+    if partial:
+        result['origin'] = partial.group(1)
+        result['destination'] = partial.group(2)
+
+    times = re.findall(r'\b(\d{4})\b', text)
+    labels = ['out', 'off', 'on', 'in']
+    for i, t in enumerate(times[:4]):
+        result[labels[i]] = t
+
+    return result if result else None
+
+
+def translate_message(msg: dict) -> dict:
+    """Translate an ACARS message dict, returning enrichment fields.
+
+    Args:
+        msg: Raw ACARS message dict with 'label', 'text'/'msg' fields.
+
+    Returns:
+        Dict with 'label_description', 'message_type', 'parsed'.
+    """
+    label = msg.get('label')
+    text = msg.get('text') or msg.get('msg') or ''
+
+    label_description = translate_label(label)
+    message_type = classify_message_type(label, text)
+
+    parsed: dict | None = None
+    if message_type == 'position' or (label == 'H1' and 'POS' in text.upper()):
+        parsed = parse_position_report(text)
+    elif message_type == 'engine_data':
+        parsed = parse_engine_data(text)
+    elif message_type == 'weather':
+        parsed = parse_weather_data(text)
+    elif message_type == 'oooi':
+        parsed = parse_oooi(text)
+
+    return {
+        'label_description': label_description,
+        'message_type': message_type,
+        'parsed': parsed,
+    }