import { endpoints } from "./config.js";
import { showToast } from "./toast.js";
import {
  getBillState,
  getCachedOpenBills,
  getGuestPendingActions,
  getHashParam,
  getTableParam,
  setCachedOpenBills,
  setGuestPendingAction,
} from "./state.js";

let guestPendingPollTimer = null;
const GUEST_PENDING_POLL_MS = 15000;

export function cacheOpenBills(bills) {
  setCachedOpenBills(bills);
}

function getQueueOperatorFields() {
  const bills = getCachedOpenBills();
  if (!bills.length) {
    return { otwierajacyImie: "", otwierajacyNazwisko: "" };
  }

  let bill = bills[0];
  const billState = getBillState();
  if (billState.selectedBillId) {
    const selected = bills.find((b) => b.id === billState.selectedBillId);
    if (selected) bill = selected;
  }

  const o = bill.otwierajacy || {};
  return {
    otwierajacyImie: String(o.imie || "").trim(),
    otwierajacyNazwisko: String(o.nazwisko || "").trim(),
  };
}

export async function prefetchOpenBills() {
  const hashParam = getHashParam();
  if (!hashParam) return;
  try {
    const res = await fetch(`${endpoints.bills}?h=${encodeURIComponent(hashParam)}`);
    const result = await res.json();
    if (result.status === "success") {
      cacheOpenBills(result.data);
    }
  } catch {
    // best effort
  }
}

/**
 * Komunikat do kolejki KDS — zwykły tekst, wiersze oddzielone \n (w JSON jako entery).
 * @param {string} title
 * @param {{ label?: string, value?: string }[]} lines
 */
export function formatGuestQueueMessage(title, lines = []) {
  const rows = (Array.isArray(lines) ? lines : [])
    .map((line) => {
      const label = String(line?.label ?? "").trim();
      const value = String(line?.value ?? "").trim();
      if (!label && !value) return "";
      if (label && value) return `${label} ${value}`;
      return label || value;
    })
    .filter(Boolean);

  if (!rows.length) {
    return title;
  }

  return `${title}\n${rows.join("\n")}`;
}

export function buildWaiterCallQueueMessage() {
  return "Przywołanie kelnera";
}

export function buildBillRequestQueueMessage(docType) {
  const billState = getBillState();
  const lines = [
    { label: "Forma płatności:", value: billState.payment || "nieznana" },
    { label: "Dokument:", value: docType === "faktura" ? "faktura" : "paragon" },
  ];

  if (docType === "faktura") {
    lines.push({ label: "NIP:", value: billState.nip || "—" });
    lines.push({ label: "Firma:", value: billState.company?.name || "—" });
    const addressParts = [
      billState.company?.street,
      [billState.company?.zip, billState.company?.city].filter(Boolean).join(" "),
    ].filter(Boolean);
    if (addressParts.length) {
      lines.push({ label: "Adres:", value: addressParts.join(", ") });
    }
  }

  return formatGuestQueueMessage("Prośba o rachunek", lines);
}

export function guestActionBlockedMessage(messageType) {
  if (messageType === "waiter_call") {
    return "Kelner został już wezwany. Poczekaj, aż obsługa potwierdzi zgłoszenie na panelu.";
  }
  return "Prośba o rachunek została już wysłana. Poczekaj, aż obsługa ją obsłuży.";
}

export function updateGuestActionNavState() {
  const guestPendingActions = getGuestPendingActions();
  const waiterNav = document.querySelector(".bottom-nav .action-call");
  const billNav = document.querySelector(".bottom-nav .action-bill");
  if (waiterNav) {
    waiterNav.classList.toggle("nav-action-pending", guestPendingActions.waiter_call);
  }
  if (billNav) {
    billNav.classList.toggle("nav-action-pending", guestPendingActions.bill_request);
  }
}

export async function refreshGuestPendingActions() {
  const hashParam = getHashParam();
  const tableParam = getTableParam();
  const guestPendingActions = getGuestPendingActions();

  if (!hashParam && !tableParam) {
    return guestPendingActions;
  }

  const params = new URLSearchParams();
  if (hashParam) params.set("h", hashParam);
  if (tableParam) params.set("tableId", tableParam);

  try {
    const res = await fetch(`${endpoints.guestActionQueue}?${params.toString()}`);
    const result = await res.json();
    if (result.status === "success" && result.pending) {
      setGuestPendingAction("waiter_call", !!result.pending.waiter_call);
      setGuestPendingAction("bill_request", !!result.pending.bill_request);
      updateGuestActionNavState();
    }
  } catch {
    // best effort
  }

  return getGuestPendingActions();
}

export function startGuestPendingPoll() {
  if (guestPendingPollTimer) return;
  guestPendingPollTimer = setInterval(() => {
    if (!getHashParam() && !getTableParam()) return;
    refreshGuestPendingActions();
  }, GUEST_PENDING_POLL_MS);
}

export async function ensureGuestActionAllowed(messageType) {
  await refreshGuestPendingActions();
  if (!getGuestPendingActions()[messageType]) {
    return true;
  }
  showToast(guestActionBlockedMessage(messageType));
  return false;
}

export async function queueGuestAction(messageType, messageText, extra = {}) {
  const operator = getQueueOperatorFields();
  const body = {
    tableId: getTableParam() || null,
    qrHash: getHashParam() || null,
    messageType,
    messageText,
    otwierajacyImie: operator.otwierajacyImie,
    otwierajacyNazwisko: operator.otwierajacyNazwisko,
    extra,
  };

  try {
    const res = await fetch(endpoints.guestActionQueue, {
      method: "POST",
      headers: { "Content-Type": "application/json" },
      body: JSON.stringify(body),
      keepalive: true,
    });
    const result = await res.json().catch(() => ({}));

    if (res.status === 409 || result.code === "pending_on_kds") {
      setGuestPendingAction(messageType, true);
      updateGuestActionNavState();
      return { ok: false, reason: "pending" };
    }

    if (res.status === 429 || result.code === "rate_limited") {
      return { ok: false, reason: "error" };
    }

    if (!res.ok || result.status !== "success") {
      return { ok: false, reason: "error" };
    }

    setGuestPendingAction(messageType, true);
    updateGuestActionNavState();
    return { ok: true };
  } catch {
    return { ok: false, reason: "error" };
  }
}