Function useColumnView

app/useColumnView/index.ts:80–230

({
  rootNode,
  initialState,
  stateReducer,
}: ColumnViewOptions)

type ColumnDefinitionCache = Map<string, ColumnDefinition>;

export function useColumnView({
  rootNode,
  initialState,
  stateReducer,
}: ColumnViewOptions): ColumnViewInstance {
  const columnCache = React.useRef<ColumnDefinitionCache>(new Map());

  useEffect(() => {
    columnCache.current = new Map();
  }, [rootNode]);

  const nodeTable = useMemo<NodeTable>(
    () => generateNodeTable(rootNode),
    [rootNode]
  );

  const enhancedReducer: Reducer<ColumnViewState, ColumnViewAction> =
    useCallback(
      (state: ColumnViewState, action: ColumnViewAction): ColumnViewState => {
        let changes = columnViewReducer(state, action);

        // Don't allow the client modify history actions
        if (action.type === "GO") {
          return changes;
        }

        if (stateReducer) {
          changes = stateReducer(state, action, changes);
        }

        //we need to get rid of any history items further forward because the user has forked by navigating
        let updatedHistory = changes.history.slice(
          0,
          changes.historyCurrentIndex + 1
        );
        let historyIndex = changes.historyCurrentIndex;

        //add new entry
        const newHistoryEntry = omit(changes, "history", "historyCurrentIndex");
        updatedHistory.push(newHistoryEntry);
        historyIndex = updatedHistory.length - 1;

        return {
          ...changes,
          history: updatedHistory,
          historyCurrentIndex: historyIndex,
        };
      },
      [stateReducer]
    );

  const [state, dispatch] = useReducer<
    Reducer<ColumnViewState, ColumnViewAction>
  >(
    enhancedReducer,
    typeof initialState === "string"
      ? {
          selectedNodeId: initialState,