fix: Update preview test with correct endpoints and enhance formula reference documentation

Author: darshild1024-cpu

src/taskpane/App.tsx

@@ -813,14 +813,61 @@ const App: React.FC = () => {
       )}
 
       <section className="card">
-        <div className="card-title">Usage</div>
-        <ul className="muted">
-          <li>Array: =DSIQ("FRED-GDP", [frequency], [start_date])</li>
-          <li>Latest: =DSIQ_LATEST("FRED-GDP")</li>
-          <li>Value: =DSIQ_VALUE("FRED-GDP", "2024-01-01")</li>
-          <li>YoY: =DSIQ_YOY("FRED-GDP")</li>
-          <li>Meta: =DSIQ_META("FRED-GDP", "title")</li>
-        </ul>
+        <div className="card-title">📖 Formula Reference</div>
+        <div style={{fontSize: '13px', lineHeight: '1.6'}}>
+          
+          <div style={{marginBottom: '16px'}}>
+            <strong style={{color: '#1f2937'}}>DSIQ(series_id, [frequency], [start_date])</strong>
+            <div className="muted" style={{marginTop: '4px'}}>Returns time series data as array (spills into cells below)</div>
+            <code style={{display: 'block', marginTop: '6px', padding: '6px', background: '#f3f4f6', borderRadius: '4px', fontSize: '12px'}}>
+              =DSIQ("wb/NE.EXP.GNFS.ZS/USA")<br/>
+              =DSIQ("fred/GDP", "Q", "2020-01-01")
+            </code>
+          </div>
+          
+          <div style={{marginBottom: '16px'}}>
+            <strong style={{color: '#1f2937'}}>DSIQ_LATEST(series_id)</strong>
+            <div className="muted" style={{marginTop: '4px'}}>Returns most recent value (single cell)</div>
+            <code style={{display: 'block', marginTop: '6px', padding: '6px', background: '#f3f4f6', borderRadius: '4px', fontSize: '12px'}}>
+              =DSIQ_LATEST("wb/NE.EXP.GNFS.ZS/USA")
+            </code>
+          </div>
+          
+          <div style={{marginBottom: '16px'}}>
+            <strong style={{color: '#1f2937'}}>DSIQ_VALUE(series_id, date)</strong>
+            <div className="muted" style={{marginTop: '4px'}}>Returns value at specific date</div>
+            <code style={{display: 'block', marginTop: '6px', padding: '6px', background: '#f3f4f6', borderRadius: '4px', fontSize: '12px'}}>
+              =DSIQ_VALUE("fred/GDP", "2024-01-01")<br/>
+              =DSIQ_VALUE("bls/CUUR0000SA0", A2)
+            </code>
+          </div>
+          
+          <div style={{marginBottom: '16px'}}>
+            <strong style={{color: '#1f2937'}}>DSIQ_YOY(series_id)</strong>
+            <div className="muted" style={{marginTop: '4px'}}>Returns year-over-year % change</div>
+            <code style={{display: 'block', marginTop: '6px', padding: '6px', background: '#f3f4f6', borderRadius: '4px', fontSize: '12px'}}>
+              =DSIQ_YOY("fred/GDP")
+            </code>
+          </div>
+          
+          <div style={{marginBottom: '16px'}}>
+            <strong style={{color: '#1f2937'}}>DSIQ_META(series_id, field)</strong>
+            <div className="muted" style={{marginTop: '4px'}}>Returns metadata field (title, frequency, units, etc.)</div>
+            <code style={{display: 'block', marginTop: '6px', padding: '6px', background: '#f3f4f6', borderRadius: '4px', fontSize: '12px'}}>
+              =DSIQ_META("wb/NE.EXP.GNFS.ZS/USA", "title")<br/>
+              =DSIQ_META("fred/GDP", "frequency")<br/>
+              =DSIQ_META("bls/CUUR0000SA0", "units")
+            </code>
+          </div>
+          
+          <div className="muted" style={{marginTop: '12px', padding: '8px', background: '#eff6ff', borderRadius: '6px', fontSize: '12px'}}>
+            <strong>💡 Tips:</strong><br/>
+            • Use Search tab to find series IDs<br/>
+            • Browse by Source for data discovery<br/>
+            • Favorites/Recent for quick access<br/>
+            • DSIQ() spills automatically in Excel 365
+          </div>
+        </div>
       </section>
 
       {previewSeries && (

test.html

@@ -455,23 +455,25 @@ <h3>Tests Passed: ${passed}/${total} (${percentage}%)</h3>
             resultDiv.textContent = 'Testing preview data fetch...';
 
             try {
-                // Fetch both latest value and metadata
-                const [latestRes, metaRes] = await Promise.all([
-                    fetch(`${API_URL}/FRED-GDP?mode=latest`),
-                    fetch(`${API_URL}/FRED-GDP?mode=meta`)
+                // Fetch both latest value and metadata using real series
+                const seriesId = 'wb%2FNE.EXP.GNFS.ZS%2FUSA';
+                const [dataRes, metaRes] = await Promise.all([
+                    fetch(`${API_URL}/${seriesId}/data?limit=1`),
+                    fetch(`${API_URL}/${seriesId}`)
                 ]);
 
-                const latestData = await latestRes.json();
+                const dataData = await dataRes.json();
                 const metaData = await metaRes.json();
 
-                testResults['preview'] = latestRes.status === 200 && metaRes.status === 200;
+                testResults['preview'] = dataRes.status === 200 && metaRes.status === 200;
 
                 if (testResults['preview']) {
+                    const latestValue = dataData.data && dataData.data.length > 0 ? dataData.data[0].value : 'N/A';
                     resultDiv.className = 'result success';
-                    resultDiv.textContent = `✅ Preview data working!\n\nLatest Value: ${latestData.scalar || 'N/A'}\n\nMetadata:\n${JSON.stringify(metaData.meta, null, 2)}`;
+                    resultDiv.textContent = `✅ Preview data working!\n\nSeries: ${metaData.dataset.title}\nLatest Value: ${latestValue}\nProvider: ${metaData.dataset.provider}\nFrequency: ${metaData.dataset.frequency}\nObservations: ${metaData.dataset.observationCount}`;
                 } else {
                     resultDiv.className = 'result error';
-                    resultDiv.textContent = `❌ Preview failed\nLatest status: ${latestRes.status}\nMeta status: ${metaRes.status}`;
+                    resultDiv.textContent = `❌ Preview failed\nData status: ${dataRes.status}\nMeta status: ${metaRes.status}`;
                 }
             } catch (error) {
                 testResults['preview'] = false;