Initial commit

client/src/selectors/next-position.js

@@ -0,0 +1,80 @@
+import { createSelector } from 'redux-orm';
+import isUndefined from 'lodash/isUndefined';
+
+import orm from '../orm';
+import { dbSelector } from './common';
+import Config from '../constants/Config';
+
+const nextPosition = (items, index, excludedId) => {
+  const filteredItems = isUndefined(excludedId)
+    ? items
+    : items.filter((item) => item.id !== excludedId);
+
+  if (isUndefined(index)) {
+    const lastItem = filteredItems[filteredItems.length - 1];
+
+    return (lastItem ? lastItem.position : 0) + Config.POSITION_GAP;
+  }
+
+  const prevItem = filteredItems[index - 1];
+  const nextItem = filteredItems[index];
+
+  const prevPosition = prevItem ? prevItem.position : 0;
+
+  if (!nextItem) {
+    return prevPosition + Config.POSITION_GAP;
+  }
+
+  return prevPosition + (nextItem.position - prevPosition) / 2;
+};
+
+export const nextBoardPositionSelector = createSelector(
+  orm,
+  dbSelector,
+  (_, projectId) => projectId,
+  (_, __, index) => index,
+  (_, __, ___, excludedId) => excludedId,
+  ({ Project }, projectId, index, excludedId) => {
+    const projectModel = Project.withId(projectId);
+
+    if (!projectModel) {
+      return projectModel;
+    }
+
+    return nextPosition(projectModel.getOrderedBoardsQuerySet().toRefArray(), index, excludedId);
+  },
+);
+
+export const nextListPositionSelector = createSelector(
+  orm,
+  dbSelector,
+  (_, boardId) => boardId,
+  (_, __, index) => index,
+  (_, __, ___, excludedId) => excludedId,
+  ({ Board }, boardId, index, excludedId) => {
+    const boardModel = Board.withId(boardId);
+
+    if (!boardModel) {
+      return boardModel;
+    }
+
+    return nextPosition(boardModel.getOrderedListsQuerySet().toRefArray(), index, excludedId);
+  },
+);
+
+export const nextCardPositionSelector = createSelector(
+  orm,
+  dbSelector,
+  (_, listId) => listId,
+  (_, __, index) => index,
+  (_, __, ___, excludedId) => excludedId,
+  ({ List }, listId, index, excludedId) => {
+    const listModel = List.withId(listId);
+
+    if (!listModel) {
+      return listModel;
+    }
+
+    return nextPosition(listModel.getOrderedFilteredCardsModelArray(), index, excludedId);
+  },
+);