Add player leaderboard and homepage preview

shared/leaderboard.ts

@@ -0,0 +1,54 @@
+export const leaderboardDifficulties = [
+  "all",
+  "easy",
+  "normal",
+  "hard",
+] as const;
+export type LeaderboardDifficulty = (typeof leaderboardDifficulties)[number];
+export type LeaderboardEntry = {
+  rank: number;
+  player_id: string;
+  display_name: string;
+  best_score: number;
+  average_score: number;
+  games_played: number;
+};
+export type LeaderboardData = {
+  entries: LeaderboardEntry[];
+  leaders: LeaderboardEntry[];
+  total_players: number;
+  total_games: number;
+  matching_players: number;
+  page: number;
+  pages: number;
+};
+
+export function leaderboardFilters(
+  params: Record<string, string | string[] | undefined>,
+) {
+  const difficulty =
+    leaderboardDifficulties.find((value) => value === params.difficulty) ??
+    "all";
+  const search =
+    typeof params.q === "string" ? params.q.trim().slice(0, 64) : "";
+  const rawPage = typeof params.page === "string" ? Number(params.page) : 1;
+  const page =
+    Number.isSafeInteger(rawPage) && rawPage > 0
+      ? Math.min(rawPage, 1_000_000)
+      : 1;
+  return { difficulty, search, page };
+}
+
+export function leaderboardHref(
+  difficulty: LeaderboardDifficulty,
+  search = "",
+  page = 1,
+) {
+  const params = new URLSearchParams();
+  if (difficulty !== "all") params.set("difficulty", difficulty);
+  if (search) params.set("q", search);
+  if (page > 1) params.set("page", String(page));
+  return `/leaderboard${params.size ? `?${params}` : ""}`;
+}
+
+export const formatScore = (score: number) => score.toLocaleString("en-US");