Fix financial taxonomy snapshot normalization

lib/server/financial-taxonomy.ts

@@ -78,6 +78,49 @@ type FilingDocumentRef = {
   primaryDocument: string | null;
 };
 
+function isRecord(value: unknown): value is Record<string, unknown> {
+  return value !== null && typeof value === 'object' && !Array.isArray(value);
+}
+
+function hasRequiredDerivedRowArrays(row: unknown) {
+  return isRecord(row)
+    && Array.isArray(row.sourceConcepts)
+    && Array.isArray(row.sourceRowKeys)
+    && Array.isArray(row.sourceFactIds);
+}
+
+function hasRequiredDetailRowArrays(row: unknown) {
+  return isRecord(row)
+    && Array.isArray(row.sourceFactIds)
+    && Array.isArray(row.dimensionsSummary);
+}
+
+function isValidStatementBundlePayload(value: unknown): value is StandardizedStatementBundlePayload {
+  if (!isRecord(value) || !Array.isArray(value.rows) || !isRecord(value.detailRows)) {
+    return false;
+  }
+
+  if (!value.rows.every((row) => hasRequiredDerivedRowArrays(row))) {
+    return false;
+  }
+
+  return Object.values(value.detailRows).every((rows) => (
+    Array.isArray(rows) && rows.every((row) => hasRequiredDetailRowArrays(row))
+  ));
+}
+
+function isValidRatioBundlePayload(value: unknown): value is Pick<CompanyFinancialStatementsResponse, 'ratioRows' | 'trendSeries' | 'categories'> {
+  return isRecord(value)
+    && Array.isArray(value.ratioRows)
+    && value.ratioRows.every((row) => hasRequiredDerivedRowArrays(row));
+}
+
+function isValidKpiBundlePayload(value: unknown): value is Pick<CompanyFinancialStatementsResponse, 'kpiRows' | 'trendSeries' | 'categories'> {
+  return isRecord(value)
+    && Array.isArray(value.kpiRows)
+    && value.kpiRows.every((row) => isRecord(row) && Array.isArray(row.sourceConcepts) && Array.isArray(row.sourceFactIds));
+}
+
 function safeTicker(input: string) {
   return input.trim().toUpperCase();
 }
@@ -350,7 +393,7 @@ function detailConceptIdentity(row: DetailFinancialRow) {
 }
 
 function detailMergeKey(row: DetailFinancialRow) {
-  const dimensionsKey = [...row.dimensionsSummary]
+  const dimensionsKey = [...(row.dimensionsSummary ?? [])]
     .map((value) => value.trim().toLowerCase())
     .filter((value) => value.length > 0)
     .sort((left, right) => left.localeCompare(right))
@@ -713,10 +756,9 @@ async function buildStatementSurfaceBundle(input: {
 
   if (
     cached
-    && Array.isArray((cached as Partial<StandardizedStatementBundlePayload>).rows)
-    && typeof (cached as Partial<StandardizedStatementBundlePayload>).detailRows === 'object'
+    && isValidStatementBundlePayload(cached)
   ) {
-    return cached as StandardizedStatementBundlePayload;
+    return cached;
   }
 
   const statement = surfaceToStatementKind(input.surfaceKind);
@@ -794,8 +836,8 @@ async function buildRatioSurfaceBundle(input: {
     snapshots: input.snapshots
   });
 
-  if (cached) {
-    return cached as Pick<CompanyFinancialStatementsResponse, 'ratioRows' | 'trendSeries' | 'categories'>;
+  if (cached && isValidRatioBundlePayload(cached)) {
+    return cached;
   }
 
   const pricesByDate = await getHistoricalClosingPrices(input.ticker, input.periods.map((period) => latestPeriodDate(period)));
@@ -846,8 +888,8 @@ async function buildKpiSurfaceBundle(input: {
     snapshots: input.snapshots
   });
 
-  if (cached) {
-    return cached as Pick<CompanyFinancialStatementsResponse, 'kpiRows' | 'trendSeries' | 'categories'>;
+  if (cached && isValidKpiBundlePayload(cached)) {
+    return cached;
   }
 
   const persistedRows = aggregatePersistedKpiRows({