From cea2c055a7183a29ddf0b700b2753474973de2d3 Mon Sep 17 00:00:00 2001
From: Jason Rasmussen <jason@rasm.me>
Date: Tue, 8 Oct 2024 10:40:48 -0400
Subject: [PATCH] fix(server): timezones

---
 server/src/services/metadata.service.spec.ts | 23 ++++++++++++++++++++
 server/src/services/metadata.service.ts      | 21 +++++++-----------
 2 files changed, 31 insertions(+), 13 deletions(-)

diff --git a/server/src/services/metadata.service.spec.ts b/server/src/services/metadata.service.spec.ts
index 761521346aba8..cd7f68ab1dd8c 100644
--- a/server/src/services/metadata.service.spec.ts
+++ b/server/src/services/metadata.service.spec.ts
@@ -61,6 +61,8 @@ describe(MetadataService.name, () => {
       tagMock,
       userMock,
     } = newTestService(MetadataService));
+
+    delete process.env.TZ;
   });
 
   afterEach(async () => {
@@ -275,6 +277,27 @@ describe(MetadataService.name, () => {
       });
     });
 
+    it('should account for the server being in a non-UTC timezone', async () => {
+      process.env.TZ = 'America/Los_Angeles';
+      assetMock.getByIds.mockResolvedValue([assetStub.sidecar]);
+      metadataMock.readTags.mockResolvedValueOnce({
+        DateTimeOriginal: '2022:01:01 00:00:00',
+      });
+
+      await sut.handleMetadataExtraction({ id: assetStub.image.id });
+      expect(assetMock.upsertExif).toHaveBeenCalledWith(
+        expect.objectContaining({
+          dateTimeOriginal: new Date('2022-01-01T08:00:00.000Z'),
+        }),
+      );
+
+      expect(assetMock.update).toHaveBeenCalledWith(
+        expect.objectContaining({
+          localDateTime: new Date('2022-01-01T00:00:00.000Z'),
+        }),
+      );
+    });
+
     it('should handle lists of numbers', async () => {
       assetMock.getByIds.mockResolvedValue([assetStub.image]);
       metadataMock.readTags.mockResolvedValue({ ISO: [160] });
diff --git a/server/src/services/metadata.service.ts b/server/src/services/metadata.service.ts
index 57668355df636..a81d1b4904c27 100644
--- a/server/src/services/metadata.service.ts
+++ b/server/src/services/metadata.service.ts
@@ -577,13 +577,6 @@ export class MetadataService extends BaseService {
     const dateTime = firstDateTime(exifTags as Maybe<Tags>, EXIF_DATE_TAGS);
     this.logger.debug(`Asset ${asset.id} date time is ${dateTime}`);
 
-    // created
-    let dateTimeOriginal = dateTime?.toDate();
-    if (!dateTimeOriginal) {
-      this.logger.warn(`Asset ${asset.id} has no valid date (${dateTime}), falling back to asset.fileCreatedAt`);
-      dateTimeOriginal = asset.fileCreatedAt;
-    }
-
     // timezone
     let timeZone = exifTags.tz ?? null;
     if (timeZone == null && dateTime?.rawValue?.endsWith('+00:00')) {
@@ -598,14 +591,16 @@ export class MetadataService extends BaseService {
       this.logger.warn(`Asset ${asset.id} has no time zone information`);
     }
 
-    // offset minutes
-    const offsetMinutes = dateTime?.tzoffsetMinutes || 0;
-    let localDateTime = dateTimeOriginal;
-    if (offsetMinutes) {
-      localDateTime = new Date(dateTimeOriginal.getTime() + offsetMinutes * 60_000);
-      this.logger.debug(`Asset ${asset.id} local time is offset by ${offsetMinutes} minutes`);
+    let dateTimeOriginal = dateTime?.toDate();
+    let localDateTime = dateTime?.toDateTime().setZone('UTC', { keepLocalTime: true }).toJSDate();
+    if (!localDateTime || !dateTimeOriginal) {
+      this.logger.warn(`Asset ${asset.id} has no valid date, falling back to asset.fileCreatedAt`);
+      dateTimeOriginal = asset.fileCreatedAt;
+      localDateTime = asset.fileCreatedAt;
     }
 
+    this.logger.debug(`Asset ${asset.id} has a local time of ${localDateTime.toISOString()}`);
+
     let modifyDate = asset.fileModifiedAt;
     try {
       modifyDate = (exifTags.ModifyDate as ExifDateTime)?.toDate() ?? modifyDate;