3 files changed, 134 insertions, 0 deletions
diff --git a/frontend/src/store/configure-store.js b/frontend/src/store/configure-store.js
new file mode 100644
index 00000000..29af25ab
--- /dev/null
+++ b/frontend/src/store/configure-store.js
@@ -0,0 +1,41 @@
+import { applyMiddleware, compose, createStore } from "redux";
+import persistState from "redux-localstorage";
+import { createLogger } from "redux-logger";
+import createSagaMiddleware from "redux-saga";
+import thunk from "redux-thunk";
+import { authRedirectMiddleware } from "../auth/index";
+import rootReducer from "../reducers/index";
+import rootSaga from "../sagas/index";
+import { dummyMiddleware } from "./middlewares/dummy-middleware";
+import { viewportAdjustmentMiddleware } from "./middlewares/viewport-adjustment";
+
+const sagaMiddleware = createSagaMiddleware();
+
+let logger;
+if (process.env.NODE_ENV !== "production") {
+  logger = createLogger();
+}
+
+const middlewares = [
+  process.env.NODE_ENV === "production" ? dummyMiddleware : logger,
+  thunk,
+  sagaMiddleware,
+  authRedirectMiddleware,
+  viewportAdjustmentMiddleware
+];
+
+export let store = undefined;
+
+export default function configureStore() {
+  const configuredStore = createStore(
+    rootReducer,
+    compose(
+      persistState("auth"),
+      applyMiddleware(...middlewares)
+    )
+  );
+  sagaMiddleware.run(rootSaga);
+  store = configuredStore;
+
+  return configuredStore;
+}
diff --git a/frontend/src/store/middlewares/dummy-middleware.js b/frontend/src/store/middlewares/dummy-middleware.js
new file mode 100644
index 00000000..468b15d1
--- /dev/null
+++ b/frontend/src/store/middlewares/dummy-middleware.js
@@ -0,0 +1,3 @@
+export const dummyMiddleware = store => next => action => {
+  next(action);
+};
diff --git a/frontend/src/store/middlewares/viewport-adjustment.js b/frontend/src/store/middlewares/viewport-adjustment.js
new file mode 100644
index 00000000..132391f3
--- /dev/null
+++ b/frontend/src/store/middlewares/viewport-adjustment.js
@@ -0,0 +1,90 @@
+import {
+  SET_MAP_DIMENSIONS,
+  setMapPosition,
+  setMapScale
+} from "../../actions/map";
+import { SET_CURRENT_DATACENTER } from "../../actions/topology/building";
+import {
+  MAP_MAX_SCALE,
+  MAP_MIN_SCALE,
+  SIDEBAR_WIDTH,
+  TILE_SIZE_IN_PIXELS,
+  VIEWPORT_PADDING
+} from "../../components/app/map/MapConstants";
+import { calculateRoomListBounds } from "../../util/tile-calculations";
+
+export const viewportAdjustmentMiddleware = store => next => action => {
+  const state = store.getState();
+
+  let datacenterId = -1;
+  let mapDimensions = {};
+  if (action.type === SET_CURRENT_DATACENTER && action.datacenterId !== -1) {
+    datacenterId = action.datacenterId;
+    mapDimensions = state.map.dimensions;
+  } else if (
+    action.type === SET_MAP_DIMENSIONS &&
+    state.currentDatacenterId !== -1
+  ) {
+    datacenterId = state.currentDatacenterId;
+    mapDimensions = { width: action.width, height: action.height };
+  }
+
+  if (datacenterId !== -1) {
+    const roomIds = state.objects.datacenter[datacenterId].roomIds;
+    const rooms = roomIds.map(id => Object.assign({}, state.objects.room[id]));
+    rooms.forEach(
+      room =>
+        (room.tiles = room.tileIds.map(tileId => state.objects.tile[tileId]))
+    );
+
+    let hasNoTiles = true;
+    for (let i in rooms) {
+      if (rooms[i].tiles.length > 0) {
+        hasNoTiles = false;
+        break;
+      }
+    }
+
+    if (!hasNoTiles) {
+      const viewportParams = calculateParametersToZoomInOnRooms(
+        rooms,
+        mapDimensions.width,
+        mapDimensions.height
+      );
+      store.dispatch(setMapPosition(viewportParams.newX, viewportParams.newY));
+      store.dispatch(setMapScale(viewportParams.newScale));
+    }
+  }
+
+  next(action);
+};
+
+function calculateParametersToZoomInOnRooms(rooms, mapWidth, mapHeight) {
+  const bounds = calculateRoomListBounds(rooms);
+  const newScale = calculateNewScale(bounds, mapWidth, mapHeight);
+
+  // Coordinates of the center of the room, relative to the global origin of the map
+  const roomCenterCoordinates = {
+    x: bounds.center.x * TILE_SIZE_IN_PIXELS * newScale,
+    y: bounds.center.y * TILE_SIZE_IN_PIXELS * newScale
+  };
+
+  const newX = -roomCenterCoordinates.x + mapWidth / 2;
+  const newY = -roomCenterCoordinates.y + mapHeight / 2;
+
+  return { newScale, newX, newY };
+}
+
+function calculateNewScale(bounds, mapWidth, mapHeight) {
+  const width = bounds.max.x - bounds.min.x;
+  const height = bounds.max.y - bounds.min.y;
+
+  const scaleX =
+    (mapWidth - 2 * SIDEBAR_WIDTH) /
+    (width * TILE_SIZE_IN_PIXELS + 2 * VIEWPORT_PADDING);
+  const scaleY =
+    mapHeight / (height * TILE_SIZE_IN_PIXELS + 2 * VIEWPORT_PADDING);
+  const newScale = Math.min(scaleX, scaleY);
+
+  return Math.min(Math.max(MAP_MIN_SCALE, newScale), MAP_MAX_SCALE);
+}