feat: dashboard - add sorting and scope

src/dashboard/sortTasks.ts

@@ -0,0 +1,41 @@
+import { Task } from "@/model/task";
+
+export const TaskSortDirection = {
+	/** Oldest first (by created). */
+	ASC: "asc",
+	/** Newest first (by created). */
+	DESC: "desc",
+} as const;
+
+export type TaskSortDirection =
+	(typeof TaskSortDirection)[keyof typeof TaskSortDirection];
+
+export const TASK_SORT_DIRECTION_ORDER: TaskSortDirection[] = [
+	TaskSortDirection.ASC,
+	TaskSortDirection.DESC,
+];
+
+export function isTaskSortDirection(
+	value: unknown,
+): value is TaskSortDirection {
+	return (
+		typeof value === "string" &&
+		(TASK_SORT_DIRECTION_ORDER as string[]).includes(value)
+	);
+}
+
+const SORT_ASC_SIGN = 1;
+const SORT_DESC_SIGN = -1;
+
+/** Sort by `created`. Default: oldest first. Does not mutate input. */
+export function sortTasks(
+	tasks: Task[],
+	direction: TaskSortDirection = TaskSortDirection.ASC,
+): Task[] {
+	const sign =
+		direction === TaskSortDirection.ASC ? SORT_ASC_SIGN : SORT_DESC_SIGN;
+	return [...tasks].sort(
+		(a, b) =>
+			sign * (new Date(a.created).getTime() - new Date(b.created).getTime()),
+	);
+}