Update Match Algorithm

package.json

@@ -16,7 +16,7 @@
   "license": "ISC",
   "dependencies": {
     "@boklisten/bl-email": "^1.8.1",
-    "@boklisten/bl-model": "^0.25.37",
+    "@boklisten/bl-model": "^0.25.41",
     "@boklisten/bl-post-office": "^0.5.56",
     "@napi-rs/image": "^1.8.0",
     "@sendgrid/mail": "^7.7.0",

src/collections/match/helpers/match-finder-2/match-finder.spec.ts

@@ -22,6 +22,7 @@ import {
   groupMatchesByUser,
   seededRandom,
   shuffler,
+  createMatchableUsersWithIdPrefix,
 } from "./match-testing-utils";
 
 chai.use(chaiAsPromised);
@@ -32,6 +33,7 @@ const andrine = createFakeMatchableUser("andrine", "book1", "book2", "book3");
 const beate = createFakeMatchableUser("beate", "book1", "book2", "book3");
 
 const monika = createFakeMatchableUser("monika", "book4");
+const mons = createFakeMatchableUser("mons", "book4");
 
 const mathias = createFakeMatchableUser(
   "mathias",
@@ -40,6 +42,13 @@ const mathias = createFakeMatchableUser(
   "book3",
   "book4",
 );
+const mathea = createFakeMatchableUser(
+  "mathea",
+  "book1",
+  "book2",
+  "book3",
+  "book4",
+);
 
 describe("Full User Match", () => {
   it("should be able to full match with other user", () => {
@@ -87,7 +96,7 @@ describe("Full User Match", () => {
   it("should be able to create multiple full matches with overlapping books", () => {
     const matchFinder = new MatchFinder(
       [monika, mathias],
-      [mathias, monika, mathias],
+      [mathea, mons, mathea],
     );
     matchFinder.generateMatches();
     expect(
@@ -101,6 +110,18 @@ describe("Full User Match", () => {
       ).length,
     ).to.equal(0);
   });
+
+  it("should not be able to match users with themselves", () => {
+    const matchFinder = new MatchFinder([andrine], [andrine]);
+    const matches = matchFinder.generateMatches();
+
+    const andrineXstand = createFakeStandMatch(
+      andrine,
+      andrine.items,
+      andrine.items,
+    );
+    assert.deepEqual(matches, [andrineXstand]);
+  });
 });
 
 describe("Partly User Match", () => {
@@ -290,50 +311,52 @@ describe("Large User Groups", () => {
   it("can sufficiently match realistic user data with itself", () => {
     const shuffle = shuffler(seededRandom(12345));
     const rawData = ullern_test_users;
-    const test_users: MatchableUser[] = rawData.map(({ id, items }) => ({
-      id,
-      items: new Set(items.map((item) => item["$numberLong"])),
-    }));
+    const test_senders = createMatchableUsersWithIdPrefix(rawData, "_sender");
+    const test_receivers = createMatchableUsersWithIdPrefix(
+      rawData,
+      "_receiver",
+    );
 
     const matchFinder = new MatchFinder(
-      shuffle(test_users.slice()),
-      shuffle(test_users.slice()),
+      shuffle(test_senders.slice()),
+      shuffle(test_receivers.slice()),
     );
 
     const matches = Array.from(matchFinder.generateMatches());
 
     const numberOfMatchesPerType = calculateNumberOfMatchesPerType(matches);
 
     expect(numberOfMatchesPerType.userMatches).to.be.lessThan(
-      test_users.length * 1.4,
+      test_senders.length * 1.4,
     );
     expect(numberOfMatchesPerType.standMatches).to.be.lessThanOrEqual(
-      test_users.length * 0.1,
+      test_senders.length * 0.1,
     );
   });
 
   it("can sufficiently match realistic user data with a modified version of itself", () => {
     const shuffle = shuffler(seededRandom(123454332));
     const rawData = ullern_test_users;
-    const test_users: MatchableUser[] = rawData.map(({ id, items }) => ({
-      id,
-      items: new Set(items.map((item) => item["$numberLong"])),
-    }));
+    const test_senders = createMatchableUsersWithIdPrefix(rawData, "_sender");
+    const test_receivers = createMatchableUsersWithIdPrefix(
+      rawData,
+      "_receiver",
+    );
 
     const matchFinder = new MatchFinder(
-      shuffle(test_users.slice()).slice(33),
-      shuffle(test_users.slice()).slice(20),
+      shuffle(test_senders.slice()).slice(33),
+      shuffle(test_receivers.slice()).slice(20),
     );
 
     const matches = Array.from(matchFinder.generateMatches());
 
     const numberOfMatchesPerType = calculateNumberOfMatchesPerType(matches);
 
     expect(numberOfMatchesPerType.userMatches).to.be.lessThan(
-      test_users.flat().length * 1.4,
+      test_senders.flat().length * 1.4,
     );
     expect(numberOfMatchesPerType.standMatches).to.be.lessThanOrEqual(
-      test_users.flat().length * 0.2,
+      test_senders.flat().length * 0.2,
     );
   });
 

src/collections/match/helpers/match-finder-2/match-finder.ts

@@ -123,7 +123,7 @@ export class MatchFinder {
       );
       if (sender) {
         if (hasDifference(intersect(sentItems, sender.items), sentItems)) {
-          throw "Sender cannot give away more books than they have!";
+          throw new Error("Sender cannot give away more books than they have!");
         }
         sender.items = difference(sender.items, sentItems);
         originalSenders = removeFullyMatchedUsers(originalSenders);
@@ -146,11 +146,18 @@ export class MatchFinder {
         if (
           hasDifference(intersect(receivedItems, receiver.items), receivedItems)
         ) {
-          throw "Receiver cannot receive more books than they want!";
+          throw new Error("Receiver cannot receive more books than they want!");
         }
         receiver.items = difference(receiver.items, receivedItems);
         originalReceivers = removeFullyMatchedUsers(originalReceivers);
       }
+
+      if (
+        senderId === receiverId &&
+        match.variant === CandidateMatchVariant.UserMatch
+      ) {
+        throw new Error("Receiver and sender cannot be the same person");
+      }
     }
 
     if (originalSenders.length > 0 || originalReceivers.length > 0) {

src/collections/match/helpers/match-finder-2/match-testing-utils.ts

@@ -115,6 +115,16 @@ export const shuffler =
     return list;
   };
 
+export function createMatchableUsersWithIdPrefix(
+  rawData: { id: string; items: { $numberLong: string }[] }[],
+  idPrefix: string,
+): MatchableUser[] {
+  return rawData.map(({ id, items }) => ({
+    id: id + idPrefix,
+    items: new Set(items.map((item) => item["$numberLong"])),
+  }));
+}
+
 /**
  * Utility method to print some stats about the matching
  * so that one can evaluate the performance of the matcher

src/collections/match/helpers/match-finder-2/match-utils.ts

@@ -114,7 +114,8 @@ export function tryFindOneWayMatch(
   receivers: MatchableUser[],
 ): MatchableUser | null {
   return receivers.reduce((best: MatchableUser | null, next) => {
-    return !hasDifference(sender.items, next.items) &&
+    return sender.id !== next.id &&
+      !hasDifference(sender.items, next.items) &&
       (best === null || next.items.size < best.items.size)
       ? next
       : best;
@@ -135,6 +136,7 @@ export function tryFindTwoWayMatch(
   return (
     receivers.find(
       (receiver) =>
+        sender.id !== receiver.id &&
         !hasDifference(sender.items, receiver.items) &&
         !hasDifference(receiver.items, sender.items),
     ) ?? null
@@ -153,6 +155,9 @@ export function tryFindPartialMatch(
 ): MatchableUser | null {
   let bestReceiver: MatchableUser | null = null;
   for (const receiver of receivers) {
+    if (sender.id === receiver.id) {
+      continue;
+    }
     const matchableItems = intersect(sender.items, receiver.items);
     const bestMatchableItems = intersect(
       sender.items,

src/collections/match/match.schema.ts

@@ -61,24 +61,19 @@ const userMatchSchema = {
     ref: BlCollectionName.Items,
     default: undefined,
   },
-  // customerItems owned by sender which have been given to anyone. May differ from receivedCustomerItems
+  // unique items owned by sender which have been given to anyone. May differ from receivedBlIds
   // when a book is borrowed and handed over to someone other than the technical owner's match
-  deliveredCustomerItems: {
-    type: [ObjectId],
-    ref: BlCollectionName.CustomerItems,
-    default: undefined,
-  },
-  // items which have been received by the receiver from anyone
-  receivedCustomerItems: {
-    type: [ObjectId],
-    ref: BlCollectionName.CustomerItems,
-    default: undefined,
-  },
+  deliveredBlIds: [String],
+  // unique items which have been received by the receiver from anyone
+  receivedBlIds: [String],
   // if true, disallow handing the items out or in at a stand, only allow match exchange
   itemsLockedToMatch: {
     type: Boolean,
     default: undefined,
   },
+  // if receiver items have overrides, the generated customer items will
+  // get the deadline specified in the override instead of using the branch defined deadline
+  deadlineOverrides: [{ item: String, deadline: Date }],
 };
 
 /** @see StandMatch */