const num = (v) => (v == null ? null : Number(v));
const pct = (v) => (num(v) == null ? "—" : `${Math.round(num(v))}%`);
const money = (v, cur) => (num(v) == null ? "—" : `${num(v).toFixed(2)}${cur ? " " + cur : ""}`);
const clock = (sec) => (sec ? new Date(sec * 1000).toLocaleTimeString([], { hour: "2-digit", minute: "2-digit" }) : "");

function line(label, value, percent) {
  const row = document.createElement("div");
  row.className = "row";
  const name = document.createElement("span");
  name.textContent = label;
  const val = document.createElement("span");
  val.className = "num";
  val.textContent = value;
  row.append(name, val);
  const wrap = document.createElement("div");
  wrap.append(row);
  if (percent != null) {
    const meter = document.createElement("div");
    meter.className = "meter";
    const fill = document.createElement("i");
    fill.style.width = `${Math.max(0, Math.min(100, Number(percent)))}%`;
    meter.append(fill);
    wrap.append(meter);
  }
  return wrap;
}

export default {
  title: "LLM usage",
  interval: 5,

  mount(el) {
    const box = document.createElement("div");
    box.className = "llm";
    el.append(box);
  },

  update(state, el) {
    const box = el.querySelector(".llm");
    box.textContent = "";
    if (state.offline) {
      box.textContent = "llm-cost-dashboard offline";
      return;
    }
    const c = state.claude ?? {};
    const o = state.opencode ?? {};
    box.append(
      line("Context", pct(c.context_pct), c.context_pct),
      line(`5h window ${clock(c.five_hour_resets_at)}`, pct(c.five_hour_pct), c.five_hour_pct),
      line(`7d window ${clock(c.seven_day_resets_at)}`, pct(c.seven_day_pct), c.seven_day_pct),
      line("Month", money(c.extra_used, c.extra_currency)),
      line("opencode spend", money(o.total_cost)),
    );
  },
};