Expose ViewportGridService API methods to extensions

platform/ui/src/contextProviders/ViewportGridProvider.jsx

@@ -1,20 +1,141 @@
-import React, { createContext, useContext, useReducer } from 'react';
-
-// export const VIEWPORT_GRID_DEFAULT_VALUE = {
-//   numCols: 1,
-//   numRows: 1,
-//   activeViewportIndex: 0,
-//   viewports: [],
-// };
+import React, {
+  createContext,
+  useCallback,
+  useContext,
+  useEffect,
+  useReducer,
+} from 'react';
+import PropTypes from 'prop-types';
 
 export const ViewportGridContext = createContext();
 
-export function ViewportGridProvider({ reducer, initialState, children }) {
+// export function ViewportGridProvider({ reducer, initialState, children }) {
+//   return (
+//     <ViewportGridContext.Provider value={useReducer(reducer, initialState)}>
+//       {children}
+//     </ViewportGridContext.Provider>
+//   );
+// }
+
+export function ViewportGridProvider({ children, service }) {
+  const DEFAULT_STATE = {
+    numRows: 1,
+    numCols: 1,
+    viewports: [],
+    activeViewportIndex: 0,
+  };
+
+  const viewportGridReducer = (state, action) => {
+    switch (action.type) {
+      case 'SET_ACTIVE_VIEWPORT_INDEX':
+        return { ...state, ...{ activeViewportIndex: action.payload } };
+      case 'SET_DISPLAYSET_FOR_VIEWPORT': {
+        const { viewportIndex, displaySetInstanceUID } = action.payload;
+        const viewports = state.viewports.slice();
+
+        viewports[viewportIndex] = { displaySetInstanceUID };
+
+        return { ...state, ...{ viewports } };
+      }
+      case 'SET_LAYOUT': {
+        const { numCols, numRows } = action.payload;
+        const numPanes = numCols * numRows;
+        const viewports = state.viewports.slice();
+        const activeViewportIndex =
+          state.activeViewportIndex >= numPanes ? 0 : state.activeViewportIndex;
+
+        while (viewports.length < numPanes) {
+          viewports.push({});
+        }
+        while (viewports.length > numPanes) {
+          viewports.pop();
+        }
+
+        return {
+          ...state,
+          ...{ activeViewportIndex, numCols, numRows, viewports },
+        };
+      }
+      default:
+        return action.payload;
+    }
+  };
+
+  const [viewportGridState, dispatch] = useReducer(
+    DEFAULT_STATE,
+    viewportGridReducer
+  );
+
+  const getState = useCallback(() => viewportGridState, [viewportGridState]);
+  const setActiveViewportIndex = useCallback(
+    index => dispatch({ type: 'SET_ACTIVE_VIEWPORT_INDEX', payload: index }),
+    [dispatch]
+  );
+  const setDisplaysetForViewport = useCallback(
+    ({ viewportIndex, displaySetInstanceUID }) =>
+      dispatch({
+        type: 'SET_DISPLAYSET_FOR_VIEWPORT',
+        payload: {
+          viewportIndex,
+          displaySetInstanceUID,
+        },
+      }),
+    [dispatch]
+  );
+
+  const setLayout = useCallback(
+    ({ numCols, numRows }) =>
+      dispatch({
+        type: 'SET_LAYOUT',
+        payload: {
+          numCols,
+          numRows,
+        },
+      }),
+    [dispatch]
+  );
+
+  /**
+   * Sets the implementation of a modal service that can be used by extensions.
+   *
+   * @returns void
+   */
+  useEffect(() => {
+    if (service) {
+      service.setServiceImplementation({
+        getState,
+        setActiveViewportIndex,
+        setDisplaysetForViewport,
+        setLayout,
+      });
+    }
+  }, [
+    getState,
+    service,
+    setActiveViewportIndex,
+    setDisplaysetForViewport,
+    setLayout,
+  ]);
+
+  const api = {
+    // getState,
+    setActiveViewportIndex,
+    setDisplaysetForViewport,
+    setLayout,
+  };
+
   return (
-    <ViewportGridContext.Provider value={useReducer(reducer, initialState)}>
+    <ViewportGridContext.Provider value={[viewportGridState, api]}>
       {children}
     </ViewportGridContext.Provider>
   );
 }
 
+ViewportGridProvider.propTypes = {
+  children: PropTypes.any,
+  service: PropTypes.shape({
+    setServiceImplementation: PropTypes.func,
+  }).isRequired,
+};
+
 export const useViewportGrid = () => useContext(ViewportGridContext);