From 8a432b45a48d1112b2bd8a05c9776cca51db542b Mon Sep 17 00:00:00 2001
From: Carina Wollendorfer <30310907+CarinaWolli@users.noreply.github.com>
Date: Wed, 19 Jul 2023 14:44:41 -0400
Subject: [PATCH] fix: issue with date overrides in some timezones (#10254)

* fix date overrides

* add test

---------

Co-authored-by: CarinaWolli <wollencarina@gmail.com>
---
 packages/lib/date-ranges.test.ts | 29 +++++++++++++++++++++++++++++
 packages/lib/date-ranges.ts      |  8 +++++---
 2 files changed, 34 insertions(+), 3 deletions(-)

diff --git a/packages/lib/date-ranges.test.ts b/packages/lib/date-ranges.test.ts
index 1973f8e883..237de2dfde 100644
--- a/packages/lib/date-ranges.test.ts
+++ b/packages/lib/date-ranges.test.ts
@@ -112,6 +112,35 @@ describe("buildDateRanges", () => {
       end: dayjs("2023-06-14T16:00:00Z").tz(timeZone),
     });
   });
+  it("should return correct date ranges if date override would already already be the next day in utc timezone", () => {
+    const items = [
+      {
+        date: new Date(Date.UTC(2023, 5, 13)),
+        startTime: new Date(Date.UTC(0, 0, 0, 22, 0)),
+        endTime: new Date(Date.UTC(0, 0, 0, 23, 0)),
+      },
+      {
+        days: [1, 2, 3, 4, 5],
+        startTime: new Date(Date.UTC(2023, 5, 12, 8, 0)),
+        endTime: new Date(Date.UTC(2023, 5, 12, 17, 0)),
+      },
+    ];
+    const timeZone = "America/New_York";
+
+    const dateFrom = dayjs("2023-06-13T00:00:00Z");
+    const dateTo = dayjs("2023-06-15T00:00:00Z");
+
+    const results = buildDateRanges({ availability: items, timeZone, dateFrom, dateTo });
+
+    expect(results[0]).toEqual({
+      start: dayjs("2023-06-14T02:00:00Z").tz(timeZone),
+      end: dayjs("2023-06-14T03:00:00Z").tz(timeZone),
+    });
+    expect(results[1]).toEqual({
+      start: dayjs("2023-06-14T12:00:00Z").tz(timeZone),
+      end: dayjs("2023-06-14T21:00:00Z").tz(timeZone),
+    });
+  });
 });
 
 describe("subtract", () => {
diff --git a/packages/lib/date-ranges.ts b/packages/lib/date-ranges.ts
index 5580a6e2fb..878ba8963e 100644
--- a/packages/lib/date-ranges.ts
+++ b/packages/lib/date-ranges.ts
@@ -52,9 +52,11 @@ export function processDateOverride({ item, timeZone }: { item: DateOverride; ti
   const startTime = dayjs(item.startTime).utc().subtract(dayjs().tz(timeZone).utcOffset(), "minute");
   const endTime = dayjs(item.endTime).utc().subtract(dayjs().tz(timeZone).utcOffset(), "minute");
 
+  const diffDays = startTime.startOf("day").diff(dayjs.utc(item.startTime).startOf("day"), "day");
+
   return {
-    start: date.hour(startTime.hour()).minute(startTime.minute()).second(0).tz(timeZone),
-    end: date.hour(endTime.hour()).minute(endTime.minute()).second(0).tz(timeZone),
+    start: date.add(diffDays, "day").hour(startTime.hour()).minute(startTime.minute()).second(0).tz(timeZone),
+    end: date.add(diffDays, "day").hour(endTime.hour()).minute(endTime.minute()).second(0).tz(timeZone),
   };
 }
 
@@ -105,7 +107,7 @@ export function groupByDate(ranges: DateRange[]): { [x: string]: DateRange[] } {
       },
       currentValue
     ) => {
-      const dateString = dayjs.utc(currentValue.start).format("YYYY-MM-DD");
+      const dateString = dayjs(currentValue.start).format("YYYY-MM-DD");
 
       previousValue[dateString] =
         typeof previousValue[dateString] === "undefined"