import { decodeJwtPayload, getAuthToken } from "./auth";

export type ThemeModePref = "system" | "light" | "dark";

export function getUserKeyFromToken(): string {
  const token = getAuthToken();
  if (!token) return "anon";

  const payload = decodeJwtPayload(token) ?? {};

  const candidates = [
    payload.sub,
    payload.nameid,
    payload["nameid"],
    payload["http://schemas.xmlsoap.org/ws/2005/05/identity/claims/nameidentifier"],
    payload["http://schemas.microsoft.com/ws/2008/06/identity/claims/primarysid"],
  ];

  for (const c of candidates) {
    if (typeof c === "string" && c.trim().length > 0) return c.trim();
  }

  return "anon";
}

function k(base: string) {
  return `${base}:${getUserKeyFromToken()}`;
}

export function getThemeModePref(): ThemeModePref {
  const raw = window.localStorage.getItem(k("themeMode"));
  if (raw === "light" || raw === "dark" || raw === "system") return raw;
  return "system";
}

export function setThemeModePref(v: ThemeModePref) {
  window.localStorage.setItem(k("themeMode"), v);
}

export function getAccentColor(): string {
  const raw = window.localStorage.getItem(k("accentColor"));
  if (raw && /^#[0-9a-fA-F]{6}$/.test(raw)) return raw;
  return "#15803d";
}

export function setAccentColor(v: string) {
  if (v && /^#[0-9a-fA-F]{6}$/.test(v)) window.localStorage.setItem(k("accentColor"), v);
}

export function clearAccentColor() {
  window.localStorage.removeItem(k("accentColor"));
}