use item data to detect conflicts

package.json

@@ -18,6 +18,7 @@
     "dataloader": "^2.0.0",
     "emotion-theming": "^10.0.27",
     "graphql": "^15.0.0",
+    "immer": "^6.0.3",
     "mysql2": "^2.1.0",
     "react": "^16.13.1",
     "react-dom": "^16.13.1",

src/ItemList.js

@@ -1,7 +1,7 @@
 import React from "react";
 import { Box, Image, PseudoBox, Stack, Skeleton } from "@chakra-ui/core";
 
-function ItemList({ items, wornItemIds, onWearItem }) {
+function ItemList({ items, wornItemIds, dispatchToOutfit }) {
   return (
     <Stack spacing="3">
       {items.map((item) => (
@@ -9,7 +9,7 @@ function ItemList({ items, wornItemIds, onWearItem }) {
           <Item
             item={item}
             isWorn={wornItemIds.includes(item.id)}
-            onWear={() => onWearItem(item.id)}
+            dispatchToOutfit={dispatchToOutfit}
           />
         </Box>
       ))}
@@ -33,14 +33,14 @@ function ItemListSkeleton() {
   );
 }
 
-function Item({ item, isWorn, onWear }) {
+function Item({ item, isWorn, dispatchToOutfit }) {
   return (
     <PseudoBox
       role="group"
       d="flex"
       alignItems="center"
       cursor="pointer"
-      onClick={onWear}
+      onClick={() => dispatchToOutfit({ type: "wearItem", itemId: item.id })}
     >
       <ItemThumbnail src={item.thumbnailUrl} isWorn={isWorn} />
       <Box width="3" />

src/WardrobePage.js

@@ -27,7 +27,7 @@ import OutfitPreview from "./OutfitPreview";
 import { Delay } from "./util";
 
 function WardrobePage() {
-  const { loading, error, data, wearItem } = useOutfitState();
+  const { loading, error, data, dispatch: dispatchToOutfit } = useOutfitState();
   const [searchQuery, setSearchQuery] = React.useState("");
   const toast = useToast();
 
@@ -69,8 +69,8 @@ function WardrobePage() {
         <Box gridArea="outfit" backgroundColor="gray.900">
           <OutfitPreview
             itemIds={data.wornItemIds}
-            speciesId="54"
-            colorId="75"
+            speciesId={data.speciesId}
+            colorId={data.colorId}
           />
         </Box>
         <Box gridArea="search" boxShadow="sm">
@@ -84,13 +84,13 @@ function WardrobePage() {
               <SearchPanel
                 query={searchQuery}
                 wornItemIds={data.wornItemIds}
-                onWearItem={wearItem}
+                dispatchToOutfit={dispatchToOutfit}
               />
             ) : (
               <ItemsPanel
                 zonesAndItems={data.zonesAndItems}
                 loading={loading}
-                onWearItem={wearItem}
+                dispatchToOutfit={dispatchToOutfit}
               />
             )}
           </Box>
@@ -135,7 +135,7 @@ function SearchToolbar({ query, onChange }) {
   );
 }
 
-function SearchPanel({ query, wornItemIds, onWearItem }) {
+function SearchPanel({ query, wornItemIds, dispatchToOutfit }) {
   const { loading, error, itemsById } = useItemData(ITEMS.map((i) => i.id));
 
   const normalize = (s) => s.toLowerCase();
@@ -152,13 +152,19 @@ function SearchPanel({ query, wornItemIds, onWearItem }) {
         error={error}
         results={results}
         wornItemIds={wornItemIds}
-        onWearItem={onWearItem}
+        dispatchToOutfit={dispatchToOutfit}
       />
     </Box>
   );
 }
 
-function SearchResults({ loading, error, results, wornItemIds, onWearItem }) {
+function SearchResults({
+  loading,
+  error,
+  results,
+  wornItemIds,
+  dispatchToOutfit,
+}) {
   if (loading) {
     return <ItemListSkeleton />;
   }
@@ -191,12 +197,12 @@ function SearchResults({ loading, error, results, wornItemIds, onWearItem }) {
     <ItemList
       items={results}
       wornItemIds={wornItemIds}
-      onWearItem={onWearItem}
+      dispatchToOutfit={dispatchToOutfit}
     />
   );
 }
 
-function ItemsPanel({ zonesAndItems, loading, onWearItem }) {
+function ItemsPanel({ zonesAndItems, loading, dispatchToOutfit }) {
   return (
     <Box color="green.800">
       <OutfitHeading />
@@ -217,7 +223,7 @@ function ItemsPanel({ zonesAndItems, loading, onWearItem }) {
               <ItemList
                 items={items}
                 wornItemIds={[wornItemId]}
-                onWearItem={onWearItem}
+                dispatchToOutfit={dispatchToOutfit}
               />
             </Box>
           ))}

src/useItemData.js

@@ -3,18 +3,28 @@ import { useQuery } from "@apollo/react-hooks";
 
 import { ITEMS } from "./data";
 
-function useItemData(itemIds) {
+function useItemData(itemIds, speciesId, colorId) {
   const { loading, error, data } = useQuery(
     gql`
-      query($itemIds: [ID!]!) {
+      query($itemIds: [ID!]!, $speciesId: ID!, $colorId: ID!) {
         items(ids: $itemIds) {
           id
           name
           thumbnailUrl
+
+          # This is used for wearItem actions, to resolve conflicts. We don't
+          # use it directly; we just expect it to be in the cache!
+          appearanceOn(speciesId: $speciesId, colorId: $colorId) {
+            layers {
+              zone {
+                id
+              }
+            }
+          }
         }
       }
     `,
-    { variables: { itemIds } }
+    { variables: { itemIds, speciesId, colorId } }
   );
 
   const items = (data && data.items) || [];

src/useOutfitState.js

@@ -1,9 +1,16 @@
 import React from "react";
+import gql from "graphql-tag";
+import produce, { enableMapSet } from "immer";
+import { useApolloClient } from "@apollo/react-hooks";
 
 import useItemData from "./useItemData";
 
+enableMapSet();
+
 function useOutfitState() {
-  const [wornItemIds, setWornItemIds] = React.useState([
+  const apolloClient = useApolloClient();
+  const [state, dispatch] = React.useReducer(outfitStateReducer(apolloClient), {
+    wornItemIds: new Set([
       "38913",
       "38911",
       "38912",
@@ -12,46 +19,24 @@ function useOutfitState() {
       "37229",
       "43014",
       "43397",
-  ]);
-  const [closetedItemIds, setClosetedItemIds] = React.useState(["74166"]);
-
-  const allItemIds = [...wornItemIds, ...closetedItemIds];
-
-  const { loading, error, itemsById } = useItemData(allItemIds);
-
-  const wearItem = React.useCallback(
-    (itemIdToAdd) => {
-      if (wornItemIds.includes(itemIdToAdd)) {
-        return;
-      }
-
-      let newWornItemIds = wornItemIds;
-      let newClosetedItemIds = closetedItemIds;
-
-      const itemToAdd = itemsById[itemIdToAdd];
-
-      // Move the item out of the closet.
-      newClosetedItemIds = newClosetedItemIds.filter(
-        (id) => id !== itemIdToAdd
-      );
-
-      // Move conflicting items to the closet.
-      const conflictingItemIds = newWornItemIds.filter((wornItemId) => {
-        const wornItem = itemsById[wornItemId];
-        return wornItem.zoneName === itemToAdd.zoneName;
+    ]),
+    closetedItemIds: new Set(["74166"]),
+    speciesId: "54", // Starry
+    colorId: "75", // Zafara
   });
-      newWornItemIds = newWornItemIds.filter(
-        (id) => !conflictingItemIds.includes(id)
-      );
-      newClosetedItemIds = [...newClosetedItemIds, ...conflictingItemIds];
 
-      // Add this item to the worn set.
-      newWornItemIds = [...newWornItemIds, itemIdToAdd];
+  const { speciesId, colorId } = state;
 
-      setWornItemIds(newWornItemIds);
-      setClosetedItemIds(newClosetedItemIds);
-    },
-    [wornItemIds, closetedItemIds, itemsById]
+  // It's more convenient to manage these as a Set in state, but most callers
+  // will find it more convenient to access them as arrays! e.g. for `.map()`
+  const wornItemIds = Array.from(state.wornItemIds);
+  const closetedItemIds = Array.from(state.closetedItemIds);
+
+  const allItemIds = [...state.wornItemIds, ...state.closetedItemIds];
+  const { loading, error, itemsById } = useItemData(
+    allItemIds,
+    speciesId,
+    colorId
   );
 
   const zonesAndItems = getZonesAndItems(
@@ -60,9 +45,90 @@ function useOutfitState() {
     closetedItemIds
   );
 
-  const data = { zonesAndItems, wornItemIds };
+  const data = { zonesAndItems, wornItemIds, speciesId, colorId };
 
-  return { loading, error, data, wearItem };
+  return { loading, error, data, dispatch };
+}
+
+const outfitStateReducer = (apolloClient) => (baseState, action) => {
+  switch (action.type) {
+    case "wearItem":
+      return produce(baseState, (state) => {
+        const { wornItemIds, closetedItemIds, speciesId, colorId } = state;
+        const { itemId } = action;
+
+        // Move the item out of the closet.
+        closetedItemIds.delete(itemId);
+
+        // Move conflicting items to the closet.
+        //
+        // We do this by looking them up in the Apollo Cache, which is going to
+        // include the relevant item data because the `useOutfitState` hook
+        // queries for it!
+        //
+        // (It could be possible to mess up the timing by taking an action
+        // while worn items are still partially loading, but I think it would
+        // require a pretty weird action sequence to make that happen... like,
+        // doing a search and it loads before the worn item data does? Anyway,
+        // Apollo will throw in that case, which should just essentially reject
+        // the action.)
+        const conflictingIds = findItemConflicts(itemId, state, apolloClient);
+        for (const conflictingId of conflictingIds) {
+          wornItemIds.delete(conflictingId);
+          closetedItemIds.add(conflictingId);
+        }
+
+        // Add this item to the worn set.
+        wornItemIds.add(itemId);
+      });
+    default:
+      throw new Error(`unexpected action ${action}`);
+  }
+};
+
+function findItemConflicts(itemIdToAdd, state, apolloClient) {
+  const { wornItemIds, speciesId, colorId } = state;
+
+  const { items } = apolloClient.readQuery({
+    query: gql`
+      query($itemIds: [ID!]!, $speciesId: ID!, $colorId: ID!) {
+        items(ids: $itemIds) {
+          id
+          appearanceOn(speciesId: $speciesId, colorId: $colorId) {
+            layers {
+              zone {
+                id
+              }
+            }
+          }
+        }
+      }
+    `,
+    variables: {
+      itemIds: [itemIdToAdd, ...wornItemIds],
+      speciesId,
+      colorId,
+    },
+  });
+  const itemToAdd = items.find((i) => i.id === itemIdToAdd);
+  const itemToAddZoneIds = itemToAdd.appearanceOn.layers.map((l) => l.zone.id);
+  const wornItems = Array.from(wornItemIds).map((id) =>
+    items.find((i) => i.id === id)
+  );
+
+  const conflictingIds = [];
+  for (const wornItem of wornItems) {
+    const wornItemZoneIds = wornItem.appearanceOn.layers.map((l) => l.zone.id);
+
+    const hasConflict = wornItemZoneIds.some((zid) =>
+      itemToAddZoneIds.includes(zid)
+    );
+    if (hasConflict) {
+      conflictingIds.push(wornItem.id);
+    }
+  }
+
+  return conflictingIds;
 }
 
 function getZonesAndItems(itemsById, wornItemIds, closetedItemIds) {

yarn.lock

@@ -6109,6 +6109,11 @@ immer@1.10.0:
   resolved "https://registry.yarnpkg.com/immer/-/immer-1.10.0.tgz#bad67605ba9c810275d91e1c2a47d4582e98286d"
   integrity sha512-O3sR1/opvCDGLEVcvrGTMtLac8GJ5IwZC4puPrLuRj3l7ICKvkmA0vGuU9OW8mV9WIBRnaxp5GJh9IEAaNOoYg==
 
+immer@^6.0.3:
+  version "6.0.3"
+  resolved "https://registry.yarnpkg.com/immer/-/immer-6.0.3.tgz#94d5051cd724668160a900d66d85ec02816f29bd"
+  integrity sha512-12VvNrfSrXZdm/BJgi/KDW2soq5freVSf3I1+4CLunUM8mAGx2/0Njy0xBVzi5zewQZiwM7z1/1T+8VaI7NkmQ==
+
 import-cwd@^2.0.0:
   version "2.1.0"
   resolved "https://registry.yarnpkg.com/import-cwd/-/import-cwd-2.1.0.tgz#aa6cf36e722761285cb371ec6519f53e2435b0a9"