feat: e2e privacy integration

pkg/store/store.go

@@ -380,12 +380,18 @@ func (s *Store) PendingTxnCount() (int, error) {
 }
 
 func (s *Store) LastBlock() (uint64, error) {
-	var lastBlock uint64
+	var lastBlock sql.NullInt64
 	err := s.db.QueryRow("SELECT value FROM integers WHERE key = 'last_block'").Scan(&lastBlock)
 	if err != nil {
+		if err == sql.ErrNoRows {
+			return 0, nil
+		}
 		return 0, err
 	}
-	return lastBlock, nil
+	if !lastBlock.Valid {
+		return 0, nil
+	}
+	return uint64(lastBlock.Int64), nil
 }
 
 func (s *Store) SetLastBlock(blockNum uint64) error {

pkg/store/store_test.go

@@ -313,6 +313,34 @@ func TestStore(t *testing.T) {
 		}
 	})
 
+	t.Run("LastBlock and SetBlockNo", func(t *testing.T) {
+		st, err := store.NewStore(db)
+		if err != nil {
+			t.Fatalf("Failed to create store: %s", err)
+		}
+
+		lastBlock, err := st.LastBlock()
+		if err != nil {
+			t.Fatalf("Failed to get last block: %s", err)
+		}
+		if lastBlock != 0 {
+			t.Fatalf("Expected last block 0, got %d", lastBlock)
+		}
+
+		err = st.SetLastBlock(3)
+		if err != nil {
+			t.Fatalf("Failed to set block number: %s", err)
+		}
+
+		lastBlock, err = st.LastBlock()
+		if err != nil {
+			t.Fatalf("Failed to get last block: %s", err)
+		}
+		if lastBlock != 3 {
+			t.Fatalf("Expected last block 3, got %d", lastBlock)
+		}
+	})
+
 	t.Run("MarkSettlementComplete", func(t *testing.T) {
 		st, err := store.NewStore(db)
 		if err != nil {