import { useEffect, useState } from "react";
import { useTranslation } from "react-i18next";
import { CARWASH_PAY_AT, CARWASH_PROGRAM_ID, CARWASH_VALIDATION_MODES, VEHICLE_CLASSES, type CarWashPayAt, type VehicleClass } from "@parking/shared";
import { fetchValidationPrograms, type ValidationProgramView } from "../../api.js";
import { StationForm, defaultProgram } from "../../ValidationSetup.js";
import { fetchCarwashSettings, saveCarwashSettings, type CarwashSettingsView } from "./api.js";

// Setup → Car wash: the master data (vehicle categories, services, the category ×
// service price matrix) and the parking SPONSORSHIP a wash grants — the latter is a
// validation program (id "carwash"), composed with the same editor the merchant
// programs use. See wiki/decisions/venue-modules.md ("v1 answers").

type Item = { id?: string; name: string; active: boolean; visionClasses?: VehicleClass[] };

const fromMinor = (v: number | undefined): string => (v == null ? "" : (v / 100).toFixed(2).replace(/\.00$/, ""));
const toMinor = (s: string): number | null => {
  const v = s.trim();
  if (v === "") return null;
  const n = Number(v);
  return Number.isFinite(n) && n >= 0 ? Math.round(n * 100) : null;
};

function ListEditor({
  title,
  items,
  onChange,
  addLabel,
  visionMap,
}: {
  title: string;
  items: Item[];
  onChange: (items: Item[]) => void;
  addLabel: string;
  /** Categories only: offer the vision vocabulary as chips under each row — the site's
   *  own "car, sedan → Vetura" mapping (venue-modules.md §Vehicle category). */
  visionMap?: boolean;
}) {
  const { t } = useTranslation();
  const toggleClass = (i: number, cls: VehicleClass) =>
    onChange(
      items.map((x, j) => {
        if (j !== i) return x;
        const cur = new Set(x.visionClasses ?? []);
        cur.has(cls) ? cur.delete(cls) : cur.add(cls);
        return { ...x, visionClasses: VEHICLE_CLASSES.filter((c) => cur.has(c)) };
      }),
    );
  return (
    <div className="grid gap-1.5">
      <div className="text-[0.6875rem] uppercase tracking-wider text-term-muted">{title}</div>
      {items.map((it, i) => (
        <div key={it.id ?? `new-${i}`} className="grid gap-1">
        <div className="flex items-center gap-2">
          <input
            className="input flex-1"
            value={it.name}
            onChange={(e) => onChange(items.map((x, j) => (j === i ? { ...x, name: e.target.value } : x)))}
          />
          <label className="flex items-center gap-1 text-[0.75rem] text-term-muted">
            <input
              type="checkbox"
              className="accent-term-amber"
              checked={it.active}
              onChange={(e) => onChange(items.map((x, j) => (j === i ? { ...x, active: e.target.checked } : x)))}
            />
            {t("wash.active")}
          </label>
          <button type="button" className="btn btn-ghost btn-sm" onClick={() => onChange(items.filter((_, j) => j !== i))}>
            ✕
          </button>
        </div>
        {visionMap && (
          <div className="flex flex-wrap items-center gap-1 pl-1">
            <span className="mr-1 text-[0.625rem] uppercase tracking-wider text-term-muted">{t("wash.visionClasses")}</span>
            {VEHICLE_CLASSES.map((cls) => {
              const on = (it.visionClasses ?? []).includes(cls);
              return (
                <button key={cls} type="button" className={`btn btn-sm ${on ? "btn-primary" : "btn-ghost"}`} onClick={() => toggleClass(i, cls)}>
                  {t(`vehicleClass.${cls}`)}
                </button>
              );
            })}
          </div>
        )}
        </div>
      ))}
      <button type="button" className="btn btn-sm self-start" onClick={() => onChange([...items, { name: "", active: true }])}>
        + {addLabel}
      </button>
    </div>
  );
}

export function CarWashSetup({ canEdit }: { canEdit: boolean }) {
  const { t } = useTranslation();
  const [settings, setSettings] = useState<CarwashSettingsView | null>(null);
  const [categories, setCategories] = useState<Item[]>([]);
  const [services, setServices] = useState<Item[]>([]);
  /** Price inputs keyed "categoryId|serviceId" (major units as typed). New rows have no
   *  id yet, so the matrix keys use the row INDEX until saved. */
  const [prices, setPrices] = useState<Record<string, string>>({});
  /** Where the money is taken — a SITE policy (user, 2026-09-05), not a per-order radio. */
  const [payAt, setPayAt] = useState<CarWashPayAt>("booth");
  /** Confidence floor for a vision read to flag a downgrade (percent, as typed). */
  const [threshold, setThreshold] = useState("80");
  const [msg, setMsg] = useState<string | null>(null);
  const [program, setProgram] = useState<ValidationProgramView | null>(null);

  function load() {
    fetchCarwashSettings()
      .then((s) => {
        setSettings(s);
        setCategories(s.categories.map((c) => ({ id: c.id, name: c.name, active: c.active, visionClasses: c.visionClasses })));
        setServices(s.services.map((x) => ({ id: x.id, name: x.name, active: x.active })));
        const p: Record<string, string> = {};
        for (const r of s.prices) p[`${r.categoryId}|${r.serviceId}`] = fromMinor(r.priceMinor);
        setPrices(p);
        setPayAt(s.payAt);
        setThreshold(String(Math.round(s.visionThreshold * 100)));
      })
      .catch((e) => setMsg((e as Error).message));
    fetchValidationPrograms()
      .then((r) => {
        const existing = r.programs.find((p) => p.id === CARWASH_PROGRAM_ID);
        setProgram(existing ?? { id: CARWASH_PROGRAM_ID, ...defaultProgram(CARWASH_PROGRAM_ID, t("wash.sponsorshipLabel")) });
      })
      .catch(() => {});
  }
  useEffect(load, []); // eslint-disable-line react-hooks/exhaustive-deps

  const keyOf = (c: Item, ci: number, s: Item, si: number) => `${c.id ?? `#${ci}`}|${s.id ?? `#${si}`}`;

  async function save() {
    setMsg(null);
    try {
      const listBody = {
        categories: categories.map((c) => ({ ...(c.id ? { id: c.id } : {}), name: c.name.trim(), active: c.active, visionClasses: c.visionClasses ?? [] })),
        services: services.map((s) => ({ ...(s.id ? { id: s.id } : {}), name: s.name.trim(), active: s.active })),
      };
      // New rows have no id until the server assigns one, and the price matrix is keyed
      // by ids — so save the lists first, map each new row to the id that came back (the
      // server returns rows in the order sent), then save the prices in a second call.
      // One button, two requests; the user just sees "Saved."
      let cats = categories;
      let svcs = services;
      if (categories.some((c) => !c.id) || services.some((s) => !s.id)) {
        // Keep only the prices whose rows survive this save (a removed row's prices
        // would be refused as unknown ids).
        const keepC = new Set(categories.map((c) => c.id).filter(Boolean));
        const keepS = new Set(services.map((s) => s.id).filter(Boolean));
        const first = await saveCarwashSettings({
          ...listBody,
          prices: (settings?.prices ?? []).filter((p) => keepC.has(p.categoryId) && keepS.has(p.serviceId)),
        });
        cats = categories.map((c, i) => ({ ...c, id: c.id ?? first.categories[i]?.id }));
        svcs = services.map((s, i) => ({ ...s, id: s.id ?? first.services[i]?.id }));
      }
      const priceRows: { categoryId: string; serviceId: string; priceMinor: number }[] = [];
      categories.forEach((c, ci) =>
        services.forEach((s, si) => {
          const v = toMinor(prices[keyOf(c, ci, s, si)] ?? "");
          const cid = cats[ci]?.id;
          const sid = svcs[si]?.id;
          if (v != null && cid && sid) priceRows.push({ categoryId: cid, serviceId: sid, priceMinor: v });
        }),
      );
      const thr = Number(threshold);
      const saved = await saveCarwashSettings({
        categories: cats.map((c) => ({ ...(c.id ? { id: c.id } : {}), name: c.name.trim(), active: c.active, visionClasses: c.visionClasses ?? [] })),
        services: svcs.map((s) => ({ ...(s.id ? { id: s.id } : {}), name: s.name.trim(), active: s.active })),
        prices: priceRows,
        payAt,
        ...(Number.isFinite(thr) && thr >= 0 && thr <= 100 ? { visionThreshold: thr / 100 } : {}),
      });
      setSettings(saved);
      setPayAt(saved.payAt);
      setThreshold(String(Math.round(saved.visionThreshold * 100)));
      setCategories(saved.categories.map((c) => ({ id: c.id, name: c.name, active: c.active, visionClasses: c.visionClasses })));
      setServices(saved.services.map((x) => ({ id: x.id, name: x.name, active: x.active })));
      const p: Record<string, string> = {};
      for (const r of saved.prices) p[`${r.categoryId}|${r.serviceId}`] = fromMinor(r.priceMinor);
      setPrices(p);
      setMsg(t("wash.saved"));
    } catch (e) {
      setMsg((e as Error).message);
    }
  }

  const currency = settings?.currency ?? "";

  return (
    <div className="mt-6 flex flex-wrap items-start gap-6">
      <section className="card w-full max-w-2xl p-4">
        <div className="grid gap-4">
          <ListEditor title={t("wash.categories")} items={categories} onChange={setCategories} addLabel={t("wash.addCategory")} visionMap />
          <ListEditor title={t("wash.services")} items={services} onChange={setServices} addLabel={t("wash.addService")} />

          <div>
            <div className="text-[0.6875rem] uppercase tracking-wider text-term-muted">
              {t("wash.prices")} {currency && <span className="normal-case tracking-normal">({currency})</span>}
            </div>
            <span className="hint">{t("wash.pricesHint")}</span>
            {categories.length > 0 && services.length > 0 && (
              <div className="mt-2 overflow-x-auto">
                <table className="text-[0.75rem]">
                  <thead>
                    <tr>
                      <th className="py-1 pr-3 text-left text-term-muted"></th>
                      {services.map((s, si) => (
                        <th key={s.id ?? `#${si}`} className="py-1 pr-3 text-left">{s.name || "…"}</th>
                      ))}
                    </tr>
                  </thead>
                  <tbody>
                    {categories.map((c, ci) => (
                      <tr key={c.id ?? `#${ci}`}>
                        <td className="py-1 pr-3 font-semibold">{c.name || "…"}</td>
                        {services.map((s, si) => {
                          const k = keyOf(c, ci, s, si);
                          return (
                            <td key={k} className="py-1 pr-3">
                              <input
                                className="input w-24 text-right tabular-nums"
                                value={prices[k] ?? ""}
                                disabled={!canEdit}
                                onChange={(e) => setPrices((p) => ({ ...p, [k]: e.target.value }))}
                                placeholder="—"
                              />
                            </td>
                          );
                        })}
                      </tr>
                    ))}
                  </tbody>
                </table>
              </div>
            )}
          </div>

          <div className="field">
            <span className="label">{t("wash.payAt")}</span>
            <div className="flex gap-4 text-[0.75rem]">
              {CARWASH_PAY_AT.map((v) => (
                <label key={v} className="flex items-center gap-1.5">
                  <input type="radio" name="carwash-payAt" className="accent-term-amber" checked={payAt === v} disabled={!canEdit} onChange={() => setPayAt(v)} />
                  {t(v === "booth" ? "wash.payAtBooth" : "wash.payAtBay")}
                </label>
              ))}
            </div>
            <span className="hint">{t(payAt === "booth" ? "wash.payAtBoothHint" : "wash.payAtBayHint")}</span>
          </div>
          <div className="field">
            <span className="label">{t("wash.visionThreshold")}</span>
            <div className="flex items-center gap-2">
              <input className="input w-20 text-right tabular-nums" inputMode="numeric" value={threshold} disabled={!canEdit} onChange={(e) => setThreshold(e.target.value)} />
              <span className="text-[0.75rem] text-term-muted">%</span>
            </div>
            <span className="hint">{t("wash.visionThresholdHint")}</span>
          </div>

          {canEdit && (
            <div className="flex items-center gap-3">
              <button type="button" className="btn btn-primary btn-sm" onClick={save}>{t("wash.save")}</button>
              {msg && <span className="text-[0.75rem] text-term-muted">{msg}</span>}
            </div>
          )}
        </div>
      </section>

      {canEdit && program && (
        <section className="card w-full max-w-md p-4">
          <div className="text-[0.6875rem] uppercase tracking-wider text-term-muted">{t("wash.sponsorship")}</div>
          <span className="hint">{t("wash.sponsorshipHint")}</span>
          <div className="mt-2">
            <StationForm program={program} onSaved={setProgram} hideUsers modes={CARWASH_VALIDATION_MODES} />
          </div>
        </section>
      )}
    </div>
  );
}