import { useState } from "react";
import { useTranslation } from "react-i18next";
import * as Dialog from "@radix-ui/react-dialog";
import { useQuery, useQueryClient } from "@tanstack/react-query";
import {
  boothExit,
  fetchSiteConfig,
  lookupSession,
  paySession,
  printVoucher,
  type SessionLookup,
} from "./api.js";
import { qk } from "./lib/query.js";
import { formatDuration, formatMoney, formatTime } from "./lib/format.js";
import { SnapshotStrip } from "./ui/SnapshotStrip.js";

// The booth pay/exit modal. Opened when the operator submits a ticket id. Shows the
// session (entry, exit=now, duration, total owed) + entry/exit snapshots, takes
// payment, then EITHER prints an exit voucher (customer self-exits at a distant
// exit) OR fires the exit immediately (booth at/near the exit) — controlled by a
// checkbox defaulting from site_config.exitVoucherDefault. See booth-exit-flow.md.

type Phase = "review" | "paying" | "finishing" | "done" | "error";

export function BoothPayModal({ identity, onClose }: { identity: string; onClose: () => void }) {
  const { t } = useTranslation();
  const qc = useQueryClient();
  const session = useQuery({ queryKey: ["session", identity], queryFn: () => lookupSession(identity) });
  const config = useQuery({ queryKey: qk.siteConfig, queryFn: fetchSiteConfig });

  const [tender, setTender] = useState<"cash" | "card">("cash");
  const [printVoucherChecked, setPrintVoucherChecked] = useState<boolean | null>(null);
  const [phase, setPhase] = useState<Phase>("review");
  const [error, setError] = useState<string | null>(null);
  const [result, setResult] = useState<string | null>(null);

  const s: SessionLookup | undefined = session.data;
  // Checkbox default comes from config the first time it loads; operator can toggle.
  const voucher = printVoucherChecked ?? config.data?.exitVoucherDefault ?? false;

  const alreadyPaid = s?.paidAt != null;
  const canPay = s?.found && s.open && !alreadyPaid;

  async function handlePayAndExit() {
    if (!s) return;
    setError(null);
    try {
      // 1. Take payment (unless already paid — e.g. paid earlier at a kiosk).
      if (!alreadyPaid) {
        setPhase("paying");
        await paySession(identity, tender);
      }
      // 2. Voucher OR immediate exit.
      setPhase("finishing");
      if (voucher) {
        const r = await printVoucher(identity);
        setResult(t("pay.voucherPrinted", { printer: r.printedBy }));
      } else {
        const r = await boothExit(identity);
        setResult(
          r.opened
            ? t("pay.paidBarrierOpened")
            : t("pay.paidExitRecorded", { reason: r.reason ?? t("booth.openManually") }),
        );
      }
      // Refresh the live views.
      void qc.invalidateQueries({ queryKey: qk.events });
      void qc.invalidateQueries({ queryKey: qk.occupancy });
      setPhase("done");
    } catch (e) {
      setError((e as Error).message);
      setPhase("error");
    }
  }

  return (
    <Dialog.Root open onOpenChange={(o) => !o && onClose()}>
      <Dialog.Portal>
        <Dialog.Overlay className="fixed inset-0 z-40 bg-black/70" />
        <Dialog.Content
          className="fixed left-1/2 top-1/2 z-50 w-[560px] max-w-[95vw] -translate-x-1/2 -translate-y-1/2 rounded-term border border-term-border bg-term-panel font-mono text-term-text shadow-2xl"
          aria-describedby={undefined}
        >
          <div className="flex items-center justify-between border-b border-term-border bg-term-panel-2 px-4 py-2">
            <Dialog.Title className="m-0 text-[12px] font-semibold uppercase tracking-wider text-term-amber">
              {t("pay.ticket")} {identity}
            </Dialog.Title>
            <Dialog.Close className="text-term-muted hover:text-term-text" aria-label={t("common.close")}>
              ✕
            </Dialog.Close>
          </div>

          <div className="flex flex-col gap-3 p-4">
            {session.isLoading && <div className="text-term-muted">{t("pay.lookingUp")}</div>}

            {s && !s.found && (
              <div className="rounded-term border border-term-red px-3 py-2 text-term-red">
                {t("pay.noSessionFound")}
              </div>
            )}

            {s && s.found && !s.open && (
              <div className="rounded-term border border-term-amber px-3 py-2 text-term-amber">
                {t("pay.alreadyClosed", { time: formatTime(s.exitedAt) })}
              </div>
            )}

            {s && s.found && s.open && (
              <>
                {/* Session figures */}
                <div className="grid grid-cols-2 gap-x-6 gap-y-1 tabular-nums">
                  <Row label={t("pay.entry")} value={formatTime(s.enteredAt)} />
                  <Row label={t("pay.now")} value={formatTime(new Date().toISOString())} />
                  <Row
                    label={t("pay.duration")}
                    value={s.enteredAt ? formatDuration(s.enteredAt, new Date().toISOString()) : "—"}
                  />
                  <Row
                    label={t("pay.statusLabel")}
                    value={alreadyPaid ? t("pay.paid") : t("pay.unpaid")}
                    valueClass={alreadyPaid ? "text-term-green" : "text-term-amber"}
                  />
                </div>

                {/* Total */}
                <div className="flex items-end justify-between rounded-term bg-term-panel-2 px-3 py-2">
                  <span className="text-[11px] uppercase tracking-wider text-term-muted">{t("pay.total")}</span>
                  <span className="text-3xl font-bold text-term-cyan">
                    {s.amountMinor != null && s.currency
                      ? formatMoney(s.amountMinor, s.currency)
                      : alreadyPaid
                        ? t("booth.badgePaid")
                        : t("pay.noTariff")}
                  </span>
                </div>

                {/* Snapshots */}
                <SnapshotStrip identity={identity} />

                {phase !== "done" && (
                  <>
                    {/* Tender */}
                    {canPay && (
                      <div className="flex items-center gap-2">
                        <span className="text-[11px] uppercase tracking-wider text-term-muted">{t("pay.tender")}</span>
                        {(["cash", "card"] as const).map((tn) => (
                          <button
                            key={tn}
                            type="button"
                            onClick={() => setTender(tn)}
                            className={`rounded-term border px-3 py-1 text-[12px] uppercase tracking-wider ${
                              tender === tn
                                ? "border-term-amber text-term-amber"
                                : "border-term-border text-term-muted hover:text-term-text"
                            }`}
                          >
                            {t(`pay.${tn}`)}
                          </button>
                        ))}
                      </div>
                    )}

                    {/* Voucher checkbox (default from site config) */}
                    <label className="flex items-center gap-2 text-[12px]">
                      <input
                        type="checkbox"
                        checked={voucher}
                        onChange={(e) => setPrintVoucherChecked(e.target.checked)}
                      />
                      {t("pay.printExitVoucher")}
                      <span className="text-term-muted">{t("pay.selfExitHint")}</span>
                    </label>
                  </>
                )}

                {error && <div className="rounded-term border border-term-red px-3 py-2 text-term-red">{error}</div>}
                {result && (
                  <div className="rounded-term border border-term-green px-3 py-2 text-term-green">{result}</div>
                )}

                {/* Actions */}
                <div className="flex justify-end gap-2 pt-1">
                  {phase === "done" ? (
                    <button
                      type="button"
                      onClick={onClose}
                      className="rounded-term border border-term-amber px-4 py-1.5 text-[12px] uppercase tracking-wider text-term-amber"
                    >
                      {t("common.close")}
                    </button>
                  ) : (
                    <>
                      <button
                        type="button"
                        onClick={onClose}
                        className="rounded-term border border-term-border px-3 py-1.5 text-[12px] uppercase tracking-wider text-term-muted hover:text-term-text"
                      >
                        {t("common.cancel")}
                      </button>
                      <button
                        type="button"
                        onClick={handlePayAndExit}
                        disabled={phase === "paying" || phase === "finishing"}
                        className="rounded-term border border-term-green bg-term-green/10 px-4 py-1.5 text-[12px] font-semibold uppercase tracking-wider text-term-green disabled:opacity-50"
                      >
                        {phase === "paying"
                          ? t("pay.takingPayment")
                          : phase === "finishing"
                            ? voucher
                              ? t("pay.printingVoucher")
                              : t("pay.opening")
                            : alreadyPaid
                              ? voucher
                                ? t("pay.printVoucher")
                                : t("pay.openBarrier")
                              : voucher
                                ? t("pay.payAndVoucher")
                                : t("pay.payAndOpen")}
                      </button>
                    </>
                  )}
                </div>
              </>
            )}
          </div>
        </Dialog.Content>
      </Dialog.Portal>
    </Dialog.Root>
  );
}

function Row({ label, value, valueClass = "" }: { label: string; value: string; valueClass?: string }) {
  return (
    <div className="flex items-baseline justify-between">
      <span className="text-[11px] uppercase tracking-wider text-term-muted">{label}</span>
      <span className={`text-sm ${valueClass}`}>{value}</span>
    </div>
  );
}