From b6f18cbe81120a8a4dded96e0d83967caf0de20f Mon Sep 17 00:00:00 2001
From: Michael Manganiello <adamantike@users.noreply.github.com>
Date: Tue, 31 Oct 2023 06:08:34 -0400
Subject: [PATCH] fix(server): Correctly set album start and end dates (#4698)

* fix(server): Correctly set album start and end dates

Currently, the query that retrieves album assets uses
`ORDER BY assets.fileCreatedAt DESC`, which makes the existing logic
return the start/end dates reversed (with `startDate` being taken from
the first asset in the array).

Instead of using the index-based approach, this change iterates through
assets to get the min/max `fileCreatedAt`. This will avoid any future
issues, if the query ordering changes, or becomes customizable (e.g. in
case the user prefers to visualize older assets first).

* fix: Maintain constant cost and only swap variables if needed
---
 .../src/domain/album/album-response.dto.spec.ts  | 16 ++++++++++++++++
 server/src/domain/album/album-response.dto.ts    | 13 +++++++++++--
 .../src/domain/metadata/metadata.service.spec.ts |  2 +-
 server/test/fixtures/asset.stub.ts               | 10 +++++-----
 4 files changed, 33 insertions(+), 8 deletions(-)
 create mode 100644 server/src/domain/album/album-response.dto.spec.ts

diff --git a/server/src/domain/album/album-response.dto.spec.ts b/server/src/domain/album/album-response.dto.spec.ts
new file mode 100644
index 000000000..c8485af65
--- /dev/null
+++ b/server/src/domain/album/album-response.dto.spec.ts
@@ -0,0 +1,16 @@
+import { albumStub } from '@test';
+import { mapAlbum } from './album-response.dto';
+
+describe('mapAlbum', () => {
+  it('should set start and end dates', () => {
+    const dto = mapAlbum(albumStub.twoAssets, false);
+    expect(dto.startDate).toEqual(new Date('2023-02-22T05:06:29.716Z'));
+    expect(dto.endDate).toEqual(new Date('2023-02-23T05:06:29.716Z'));
+  });
+
+  it('should not set start and end dates for empty assets', () => {
+    const dto = mapAlbum(albumStub.empty, false);
+    expect(dto.startDate).toBeUndefined();
+    expect(dto.endDate).toBeUndefined();
+  });
+});
diff --git a/server/src/domain/album/album-response.dto.ts b/server/src/domain/album/album-response.dto.ts
index 9f0e134c7..b426bc37d 100644
--- a/server/src/domain/album/album-response.dto.ts
+++ b/server/src/domain/album/album-response.dto.ts
@@ -36,6 +36,15 @@ export const mapAlbum = (entity: AlbumEntity, withAssets: boolean): AlbumRespons
   const hasSharedLink = entity.sharedLinks?.length > 0;
   const hasSharedUser = sharedUsers.length > 0;
 
+  let startDate = assets.at(0)?.fileCreatedAt || undefined;
+  let endDate = assets.at(-1)?.fileCreatedAt || undefined;
+  // Swap dates if start date is greater than end date.
+  if (startDate && endDate && startDate > endDate) {
+    const temp = startDate;
+    startDate = endDate;
+    endDate = temp;
+  }
+
   return {
     albumName: entity.albumName,
     description: entity.description,
@@ -48,8 +57,8 @@ export const mapAlbum = (entity: AlbumEntity, withAssets: boolean): AlbumRespons
     sharedUsers,
     shared: hasSharedUser || hasSharedLink,
     hasSharedLink,
-    startDate: assets.at(0)?.fileCreatedAt || undefined,
-    endDate: assets.at(-1)?.fileCreatedAt || undefined,
+    startDate,
+    endDate,
     assets: (withAssets ? assets : []).map((asset) => mapAsset(asset)),
     assetCount: entity.assets?.length || 0,
   };
diff --git a/server/src/domain/metadata/metadata.service.spec.ts b/server/src/domain/metadata/metadata.service.spec.ts
index 86befcee8..e6ca7f199 100644
--- a/server/src/domain/metadata/metadata.service.spec.ts
+++ b/server/src/domain/metadata/metadata.service.spec.ts
@@ -277,7 +277,7 @@ describe(MetadataService.name, () => {
         id: assetStub.withLocation.id,
         duration: null,
         fileCreatedAt: assetStub.withLocation.createdAt,
-        localDateTime: new Date('2023-02-23T05:06:29.716Z'),
+        localDateTime: new Date('2023-02-22T05:06:29.716Z'),
       });
     });
 
diff --git a/server/test/fixtures/asset.stub.ts b/server/test/fixtures/asset.stub.ts
index 345481843..4c6288c40 100644
--- a/server/test/fixtures/asset.stub.ts
+++ b/server/test/fixtures/asset.stub.ts
@@ -434,8 +434,8 @@ export const assetStub = {
   withLocation: Object.freeze<AssetEntity>({
     id: 'asset-with-favorite-id',
     deviceAssetId: 'device-asset-id',
-    fileModifiedAt: new Date('2023-02-23T05:06:29.716Z'),
-    fileCreatedAt: new Date('2023-02-23T05:06:29.716Z'),
+    fileModifiedAt: new Date('2023-02-22T05:06:29.716Z'),
+    fileCreatedAt: new Date('2023-02-22T05:06:29.716Z'),
     owner: userStub.user1,
     ownerId: 'user-id',
     deviceId: 'device-id',
@@ -447,9 +447,9 @@ export const assetStub = {
     webpPath: null,
     thumbhash: null,
     encodedVideoPath: null,
-    createdAt: new Date('2023-02-23T05:06:29.716Z'),
-    updatedAt: new Date('2023-02-23T05:06:29.716Z'),
-    localDateTime: new Date('2023-02-23T05:06:29.716Z'),
+    createdAt: new Date('2023-02-22T05:06:29.716Z'),
+    updatedAt: new Date('2023-02-22T05:06:29.716Z'),
+    localDateTime: new Date('2023-02-22T05:06:29.716Z'),
     isFavorite: false,
     isArchived: false,
     isReadOnly: false,