moving v2 to top level

src/app/course/[courseName]/context/drag/getNewLockDate.ts

@@ -0,0 +1,25 @@
+"use client";
+import { getDateFromStringOrThrow, dateToMarkdownString } from "@/models/local/utils/timeUtils";
+
+
+export function getNewLockDate(
+  originalDueDate: string,
+  originalLockDate: string | undefined,
+  dayAsDate: Date
+): string | undefined {
+  // todo: preserve previous due date / lock date offset
+  const dueDate = getDateFromStringOrThrow(originalDueDate, "dueAt date");
+  const lockDate = originalLockDate === undefined
+    ? undefined
+    : getDateFromStringOrThrow(originalLockDate, "lockAt date");
+
+  const originalOffset = lockDate === undefined ? undefined : lockDate.getTime() - dueDate.getTime();
+
+  const newLockDate = originalOffset === undefined
+    ? undefined
+    : new Date(dayAsDate.getTime() + originalOffset);
+
+  return newLockDate === undefined
+    ? undefined
+    : dateToMarkdownString(newLockDate);
+}