fix(regimes): keep ETH timeline consistent with updated prices

api/ml_crypto_endpoints.py

@@ -13,6 +13,8 @@
 from datetime import datetime
 import logging
 import time
+import hashlib
+import json
 
 from api.utils import success_response, error_response
 from services.ml.models.btc_regime_detector import BTCRegimeDetector
@@ -139,22 +141,21 @@ async def get_crypto_regime_history(
     try:
         logger.info(f"GET /api/ml/crypto/regime-history - symbol={symbol}, lookback_days={lookback_days}")
 
-        # Check cache first
+        # A refresh may revise today's close without changing the final date.
+        history = price_history.get_cached_history(symbol, days=lookback_days)
+        if history is None or len(history) == 0:
+            return error_response(f"No historical data available for {symbol}", code=404)
+        history_revision = hashlib.sha256(json.dumps(history, separators=(',', ':')).encode()).hexdigest()
         cache_key = f"{symbol}_{lookback_days}"
         if cache_key in _regime_history_cache:
             cached_data, cache_time = _regime_history_cache[cache_key]
-            if time.time() - cache_time < _CACHE_TTL:
+            if time.time() - cache_time < _CACHE_TTL and cached_data.get('source_history_revision') == history_revision:
                 logger.debug(f"[Cache HIT] Returning cached regime history for {cache_key}")
                 return success_response(cached_data)
             else:
                 logger.debug(f"[Cache EXPIRED] Removing stale cache for {cache_key}")
                 del _regime_history_cache[cache_key]
 
-        # Get data
-        history = price_history.get_cached_history(symbol, days=lookback_days)
-        if history is None or len(history) == 0:
-            return error_response(f"No historical data available for {symbol}", code=404)
-
         data = pd.DataFrame(history, columns=['timestamp', 'close'])
         data['timestamp'] = pd.to_datetime(data['timestamp'], unit='s')
         data.set_index('timestamp', inplace=True)
@@ -228,6 +229,7 @@ async def get_crypto_regime_history(
             'regime_ids': regime_ids,
             'symbol': symbol,
             'lookback_days': lookback_days,
+            'source_history_revision': history_revision,
             'regime_id_mapping': label_mapping,
             'economic_mapping_verified': False,
             'id_encoding': 'Rule diagnostics 0-3; unmapped HMM states 4-7',

services/ml/models/btc_regime_detector.py

@@ -49,7 +49,7 @@ def __init__(self, num_regimes: int = 4):
             0: 'Sustained bear market with significant drawdown (>30%)',
             1: 'Market pullback or high volatility period (10-30% drawdown)',
             2: 'Stable uptrend with low drawdown and moderate volatility',
-            3: 'Strong post-crash recovery at +30%/month or higher'
+            3: 'Recovery of at least +15% over 30 days after a deep drawdown'
         }
 
         # HMM model (trained on features)

static/market-regimes.html

@@ -190,7 +190,7 @@ <h1>Market Regimes</h1>
                         </td>
                         <td style="padding: 0.75rem; border: 1px solid var(--theme-border);" id="comparison-btc-confidence">--</td>
                         <td style="padding: 0.75rem; border: 1px solid var(--theme-border);" id="comparison-btc-method">--</td>
-                        <td style="padding: 0.75rem; border: 1px solid var(--theme-border);">DD ≤ -30%, 20d</td>
+                        <td id="comparison-btc-trigger" style="padding: 0.75rem; border: 1px solid var(--theme-border);">Loading...</td>
                       </tr>
                       <tr>
                         <td style="padding: 0.75rem; border: 1px solid var(--theme-border); font-weight: 600;">⟠ Ethereum</td>
@@ -199,7 +199,7 @@ <h1>Market Regimes</h1>
                         </td>
                         <td style="padding: 0.75rem; border: 1px solid var(--theme-border);" id="comparison-eth-confidence">--</td>
                         <td style="padding: 0.75rem; border: 1px solid var(--theme-border);" id="comparison-eth-method">--</td>
-                        <td style="padding: 0.75rem; border: 1px solid var(--theme-border);">DD ≤ -30%, 20d</td>
+                        <td id="comparison-eth-trigger" style="padding: 0.75rem; border: 1px solid var(--theme-border);">Loading...</td>
                       </tr>
                     </tbody>
                   </table>
@@ -608,6 +608,7 @@ <h4 style="margin: 0;">Historical Regime Timeline</h4>
         if (btcData) {
           const btc = btcData.data || btcData;
           if (btc.current_regime) {
+            document.getElementById('comparison-btc-trigger').textContent = btc.rule_diagnostic?.reason || btc.rule_reason || 'No economic rule matched';
             const btcEl = document.getElementById('comparison-btc-regime');
             btcEl.textContent = btc.current_regime;
             btcEl.className = 'regime-chip ' + getRegimeClass(btc.current_regime);
@@ -619,6 +620,7 @@ <h4 style="margin: 0;">Historical Regime Timeline</h4>
         if (ethData) {
           const eth = ethData.data || ethData;
           if (eth.current_regime) {
+            document.getElementById('comparison-eth-trigger').textContent = eth.rule_diagnostic?.reason || eth.rule_reason || 'No economic rule matched';
             const ethEl = document.getElementById('comparison-eth-regime');
             ethEl.textContent = eth.current_regime;
             ethEl.className = 'regime-chip ' + getRegimeClass(eth.current_regime);

static/modules/eth-regime-chart.js

@@ -94,7 +94,8 @@ async function loadETHRegimeData(lookbackDays) {
         }
         if (note) {
             note.textContent = [historyResult.data.note, historyResult.data.history_limitation,
-                `${historyResult.data.dates?.length || 0} observed days; ${historyResult.data.unknown_days || 0} Unknown days.`].filter(Boolean).join(' ');
+                `${historyResult.data.dates?.length || 0} observed days; ${historyResult.data.unknown_days || 0} Unknown days.`,
+                historyResult.data.dates?.length ? `Latest observation: ${historyResult.data.dates.at(-1)} — ${historyResult.data.regimes?.at(-1) || 'Unknown'}.` : ''].filter(Boolean).join(' ');
         }
 
         // Create timeline chart
@@ -151,7 +152,8 @@ function createTimelineChart(historyData) {
                     borderWidth: 3,
                     fill: false,
                     tension: 0.1,
-                    pointRadius: 0,
+                    pointRadius: context => context.dataIndex === dates.length - 1 ? 4 : 0,
+                    pointBackgroundColor: context => ETH_REGIME_CONFIG.regimeColors[regimes[context.dataIndex]]?.border || '#627eea',
                     pointHoverRadius: 5,
                     order: 1  // Draw on top of annotations
                 }
@@ -247,8 +249,10 @@ function createRegimeBoxAnnotations(dates, regimes) {
                 // Create box annotation for this regime period
                 annotations[`regime_${startIndex}_${endIndex}`] = {
                     type: 'box',
-                    xMin: dates[startIndex],
-                    xMax: dates[endIndex],
+                    // Daily observations occupy half a day on either side of their timestamp.
+                    // Equal endpoints would make a one-day regime invisible.
+                    xMin: Date.parse(dates[startIndex]) - 12 * 60 * 60 * 1000,
+                    xMax: Date.parse(dates[endIndex]) + 12 * 60 * 60 * 1000,
                     yScaleID: 'y',
                     backgroundColor: regimeConfig.bg,
                     borderColor: 'transparent',

static/tests/eth-regime-chart.test.js

@@ -30,3 +30,17 @@ test('API reason is visible, stale chart is destroyed, and a successful retry cl
     expect(document.getElementById('eth-regime-error-message').style.display).toBe('none');
     expect(document.getElementById('eth-regime-chart-container').classList.contains('loading')).toBe(false);
 });
+
+test('a one-day Expansion has a nonzero zone and a visible latest-observation marker',async()=>{
+    const revised = {...history, regimes:['Bear Market','Bull Market','Expansion']};
+    fetch.mockResolvedValue({ok:true,status:200,json:async()=>({ok:true,data:revised})});
+    await initializeETHRegimeChart();
+    const [,config] = Chart.mock.calls.at(-1);
+    const box = config.options.plugins.annotation.annotations.regime_2_2;
+    expect(box.xMax-box.xMin).toBe(24*60*60*1000);
+    expect(box.backgroundColor).toBe('rgba(59, 130, 246, 0.2)');
+    expect(config.data.datasets[0].pointRadius({dataIndex:2})).toBe(4);
+    expect(config.data.datasets[0].pointBackgroundColor({dataIndex:2})).toBe('#3b82f6');
+    expect(config.data.datasets[0].pointRadius({dataIndex:1})).toBe(0);
+    expect(document.getElementById('eth-regime-history-note').textContent).toContain('Latest observation: 2026-10-01 — Expansion');
+});

tests/unit/test_crypto_regime_without_hmm.py

@@ -77,3 +77,36 @@ async def predict_regime(self, **kwargs):
     assert data['confidence'] is None
     assert data['hmm_availability'] == 'Unavailable'
     assert data['hmm_unavailability_reason'] == 'No compatible ETH artifact'
+
+
+@pytest.mark.asyncio
+async def test_history_cache_invalidates_when_same_day_close_is_revised(monkeypatch):
+    import api.ml_crypto_endpoints as module
+    index = pd.date_range('2026-10-01', periods=2)
+    history = [(int(d.timestamp()), 100.0) for d in index]
+    prepare = AsyncMock()
+    class Detector:
+        async def prepare_regime_features(self, **kwargs):
+            await prepare()
+            return pd.DataFrame({'drawdown_from_peak': [-0.5, -0.4],
+                'days_since_peak': 30, 'trend_30d': [0.08, 0.154 if history[-1][1] > 100 else 0.14],
+                'market_volatility': 0.3}, index=index)
+        def load_model(self, name):
+            return False
+    monkeypatch.setattr(module, 'BTCRegimeDetector', Detector)
+    monkeypatch.setattr(module.price_history, 'get_cached_history', lambda *args, **kwargs: history)
+    monkeypatch.setattr(module, '_regime_history_cache', {})
+    async def get():
+        response = await module.get_crypto_regime_history(symbol='ETH', lookback_days=365)
+        assert response.status_code == 200
+        return json.loads(response.body)['data']
+    first = await get()
+    assert first['regimes'][-1] == 'Bull Market'
+    assert await get() == first
+    assert prepare.await_count == 1
+    history[-1] = (history[-1][0], 101.0)  # Same date, changed close.
+    revised = await get()
+    assert revised['dates'] == first['dates']
+    assert revised['regimes'][-1] == 'Expansion'
+    assert revised['source_history_revision'] != first['source_history_revision']
+    assert prepare.await_count == 2