fix(dataset): echo back selected datasets not in the first page (#17616)

web/src/components/knowledge-base-item.tsx

@@ -1,5 +1,8 @@
 import { DocumentParserType } from '@/constants/knowledge';
-import { useFetchKnowledgeList } from '@/hooks/use-knowledge-request';
+import {
+  useFetchDatasetsByIds,
+  useFetchKnowledgeList,
+} from '@/hooks/use-knowledge-request';
 import { IDataset } from '@/interfaces/database/dataset';
 import { useBuildQueryVariableOptions } from '@/pages/agent/hooks/use-get-begin-query';
 import { useDebounce } from 'ahooks';
@@ -36,12 +39,31 @@ export function useDisableDifferenceEmbeddingDataset(name: string) {
   } = useFetchKnowledgeList(false, debouncedSearchString);
   const datasetCacheRef = useRef(new Map<string, IDataset>());
 
+  const selectedDatasetIds = useMemo(
+    () => (Array.isArray(datasetId) ? datasetId : []),
+    [datasetId],
+  );
+
+  // Selected dataset IDs that are neither in the currently loaded page nor
+  // already cached. These need to be fetched by ID so their names can be
+  // echoed back in the form field (the paginated list may not contain them).
+  const missingIds = useMemo(() => {
+    const loadedIds = new Set(datasetListOrigin.map((d) => d.id));
+    return selectedDatasetIds.filter(
+      (id) => !loadedIds.has(id) && !datasetCacheRef.current.has(id),
+    );
+  }, [datasetListOrigin, selectedDatasetIds]);
+
+  const { data: missingDatasets } = useFetchDatasetsByIds(missingIds);
+
   const datasetList = useMemo(() => {
     datasetListOrigin.forEach((dataset) => {
       datasetCacheRef.current.set(dataset.id, dataset);
     });
+    missingDatasets?.forEach((dataset) => {
+      datasetCacheRef.current.set(dataset.id, dataset);
+    });
 
-    const selectedDatasetIds = Array.isArray(datasetId) ? datasetId : [];
     const selectedDatasets = selectedDatasetIds
       .map((id) => datasetCacheRef.current.get(id))
       .filter(Boolean) as IDataset[];
@@ -54,7 +76,7 @@ export function useDisableDifferenceEmbeddingDataset(name: string) {
         ]),
       ).values(),
     );
-  }, [datasetId, datasetListOrigin]);
+  }, [datasetListOrigin, selectedDatasetIds, missingDatasets]);
 
   const selectedEmbedId = useMemo(() => {
     const data = datasetList?.find((item) => item.id === datasetId?.[0]);