import { useState } from "react";
import { useTranslation } from "react-i18next";
import { useQuery } from "@tanstack/react-query";
import { fetchShifts, type ShiftSummary, type SessionUser } from "./api.js";
import { formatMoney, formatDuration, formatRelativeDateTime } from "./lib/format.js";

// Completed shift history. Scope is enforced SERVER-SIDE by permission: an operator
// gets only their own shifts; an admin (shift:cash) gets all + a date/operator
// filter. The screen mirrors that — it shows the filter only when the server
// reports scope:"all". Each row is one signed shift_z_report; expanding it shows the
// drawer reconciliation. See wiki/concepts/shift.md.

function money(minor: number, currency: string | null): string {
  return currency ? formatMoney(minor, currency) : (minor / 100).toFixed(2);
}

export function ShiftsHistory({ user }: { user: SessionUser | null }) {
  const { t } = useTranslation();
  // Admin filter inputs (only sent when the server grants the "all" scope; for an
  // operator the server ignores them anyway).
  const [operator, setOperator] = useState("");
  const [from, setFrom] = useState("");
  const [to, setTo] = useState("");
  // The applied filter (separate from the inputs, so typing doesn't refetch).
  const [applied, setApplied] = useState<{ operator?: string; from?: string; to?: string }>({});

  const q = useQuery({
    queryKey: ["shifts", applied],
    queryFn: () => fetchShifts(applied),
  });

  const isAdmin = q.data?.scope === "all";
  const shifts = q.data?.shifts ?? [];

  function apply() {
    setApplied({
      operator: operator.trim() || undefined,
      // A date input gives yyyy-mm-dd; widen `to` to the end of that day.
      from: from ? new Date(`${from}T00:00:00`).toISOString() : undefined,
      to: to ? new Date(`${to}T23:59:59`).toISOString() : undefined,
    });
  }
  function clear() {
    setOperator("");
    setFrom("");
    setTo("");
    setApplied({});
  }

  return (
    <div className="mx-auto max-w-4xl">
      <div className="mb-3 flex items-center justify-between">
        <h1 className="text-sm font-bold uppercase tracking-widest text-term-amber">
          {isAdmin ? t("shifts.title") : t("shifts.myTitle")}
        </h1>
      </div>

      {/* Admin-only filter: by operator + a date window over the shift start. */}
      {isAdmin && (
        <div className="card mb-3 flex flex-wrap items-end gap-3 p-3">
          <div className="field">
            <span className="label">{t("shifts.operator")}</span>
            <input
              className="input w-44"
              value={operator}
              onChange={(e) => setOperator(e.target.value)}
              placeholder={t("shifts.allOperators")}
            />
          </div>
          <div className="field">
            <span className="label">{t("shifts.filterFrom")}</span>
            <input type="date" className="input w-44" value={from} onChange={(e) => setFrom(e.target.value)} />
          </div>
          <div className="field">
            <span className="label">{t("shifts.filterTo")}</span>
            <input type="date" className="input w-44" value={to} onChange={(e) => setTo(e.target.value)} />
          </div>
          <button type="button" className="btn btn-primary btn-sm" onClick={apply}>
            {t("shifts.apply")}
          </button>
          <button type="button" className="btn btn-sm" onClick={clear}>
            {t("shifts.clear")}
          </button>
        </div>
      )}

      {q.isError && (
        <div className="mb-2 rounded-term border border-term-red px-3 py-2 text-[12px] text-term-red">
          {t("shifts.loadFailed")}
        </div>
      )}

      <div className="overflow-hidden rounded-term border border-term-border">
        <table className="w-full text-[12px] tabular-nums">
          <thead className="bg-term-panel-2 text-[11px] uppercase tracking-wider text-term-muted">
            <tr>
              {isAdmin && <th className="px-3 py-1.5 text-left">{t("shifts.operator")}</th>}
              <th className="px-3 py-1.5 text-left">{t("shifts.started")}</th>
              <th className="px-3 py-1.5 text-left">{t("shifts.ended")}</th>
              <th className="px-3 py-1.5 text-right">{t("shifts.payments")}</th>
              <th className="px-3 py-1.5 text-right">{t("shifts.cash")}</th>
              <th className="px-3 py-1.5 text-right">{t("shifts.card")}</th>
              <th className="px-3 py-1.5 text-right">{t("shifts.expectedDrawer")}</th>
            </tr>
          </thead>
          <tbody>
            {shifts.map((s) => (
              <ShiftRow key={s.id} s={s} showOperator={isAdmin} colSpan={isAdmin ? 7 : 6} />
            ))}
            {!q.isLoading && shifts.length === 0 && (
              <tr>
                <td colSpan={isAdmin ? 7 : 6} className="px-3 py-3 text-term-muted">
                  {t("shifts.none")}
                </td>
              </tr>
            )}
          </tbody>
        </table>
      </div>
    </div>
  );
}

function ShiftRow({ s, showOperator, colSpan }: { s: ShiftSummary; showOperator: boolean; colSpan: number }) {
  const { t } = useTranslation();
  const [open, setOpen] = useState(false);
  const cur = s.currency;
  const when = (iso: string) => formatRelativeDateTime(iso, t);

  return (
    <>
      <tr
        className="cursor-pointer border-t border-term-border hover:bg-term-panel-2"
        onClick={() => setOpen((o) => !o)}
      >
        {showOperator && <td className="px-3 py-1.5 text-term-text">{s.operator}</td>}
        <td className="px-3 py-1.5">{when(s.startedAt)}</td>
        <td className="px-3 py-1.5">
          {when(s.endedAt)}
          <span className="ml-2 text-term-muted">{formatDuration(s.startedAt, s.endedAt)}</span>
        </td>
        <td className="px-3 py-1.5 text-right">{s.paymentCount}</td>
        <td className="px-3 py-1.5 text-right text-term-green">{money(s.cashTotalMinor, cur)}</td>
        <td className="px-3 py-1.5 text-right text-term-cyan">{money(s.cardTotalMinor, cur)}</td>
        <td className="px-3 py-1.5 text-right font-semibold">{money(s.expectedDrawerMinor, cur)}</td>
      </tr>
      {open && (
        <tr className="border-t border-term-border/50 bg-term-bg">
          <td colSpan={colSpan} className="px-3 py-2">
            <div className="text-[11px] uppercase tracking-wider text-term-muted">{t("shifts.drawerSection")}</div>
            <div className="mt-1 grid grid-cols-2 gap-x-8 gap-y-0.5 sm:grid-cols-4">
              <Figure label={t("shifts.openingFloat")} value={money(s.openingFloatMinor, cur)} />
              <Figure label={t("shifts.cashTaken")} value={money(s.cashTotalMinor, cur)} />
              <Figure label={t("shifts.cashAdded")} value={money(s.cashAddedMinor, cur)} />
              <Figure label={t("shifts.cashRemoved")} value={money(s.cashRemovedMinor, cur)} />
            </div>
          </td>
        </tr>
      )}
    </>
  );
}

function Figure({ label, value }: { label: string; value: string }) {
  return (
    <div className="flex justify-between gap-2">
      <span className="text-term-muted">{label}</span>
      <span className="text-term-text">{value}</span>
    </div>
  );
}