Refactoring

lib/data/database/daos/knowledge_chunk_dao.dart

@@ -0,0 +1,35 @@
+import 'package:drift/drift.dart';
+import 'package:trainhub_flutter/data/database/app_database.dart';
+
+part 'knowledge_chunk_dao.g.dart';
+
+@DriftAccessor(tables: [KnowledgeChunks])
+class KnowledgeChunkDao extends DatabaseAccessor<AppDatabase>
+    with _$KnowledgeChunkDaoMixin {
+  KnowledgeChunkDao(super.db);
+
+  Future<void> insertChunk(KnowledgeChunksCompanion entry) =>
+      into(knowledgeChunks).insert(entry);
+
+  /// Returns every stored chunk, including its JSON-encoded embedding.
+  /// Loaded into memory for in-process cosine similarity scoring.
+  Future<List<KnowledgeChunk>> getAllChunks() =>
+      (select(knowledgeChunks)
+            ..orderBy([
+              (t) =>
+                  OrderingTerm(expression: t.createdAt, mode: OrderingMode.asc)
+            ]))
+          .get();
+
+  Future<int> getCount() async {
+    final rows = await select(knowledgeChunks).get();
+    return rows.length;
+  }
+
+  Future<void> deleteAll() => delete(knowledgeChunks).go();
+
+  Future<void> deleteBySourceId(String sourceId) =>
+      (delete(knowledgeChunks)
+            ..where((t) => t.sourceId.equals(sourceId)))
+          .go();
+}