const ADMIN_TOKEN_KEY = "admin_token";

function formatMoney(value) {
  const number = Number(value || 0);
  if (!Number.isFinite(number)) {
    return "Rp 0";
  }
  return new Intl.NumberFormat("id-ID", {
    style: "currency",
    currency: "IDR",
    maximumFractionDigits: 0
  }).format(number);
}

function formatDateTime(value) {
  if (!value) {
    return "-";
  }

  const date = new Date(value);
  if (Number.isNaN(date.getTime())) {
    return value;
  }

  return new Intl.DateTimeFormat("en-GB", {
    dateStyle: "medium",
    timeStyle: "short"
  }).format(date);
}

function buildQuery(query) {
  const search = new URLSearchParams();
  Object.entries(query || {}).forEach(([key, val]) => {
    if (val !== undefined && val !== null && val !== "") {
      search.append(key, String(val));
    }
  });
  return search.toString();
}

async function adminFetch(path, options = {}) {
  const token = localStorage.getItem(ADMIN_TOKEN_KEY);
  const {
    method = "GET",
    query,
    body,
    headers: extraHeaders = {},
    auth = true
  } = options;

  const suffix = buildQuery(query || {});
  const url = suffix ? `${path}?${suffix}` : path;
  const headers = {
    ...extraHeaders
  };

  if (auth) {
    if (!token) {
      throw new Error("ADMIN_AUTH_MISSING");
    }
    headers.Authorization = `Bearer ${token}`;
  }

  if (method !== "GET" && body !== undefined) {
    headers["Content-Type"] = "application/json";
  }

  const response = await fetch(url, {
    method,
    headers,
    body: method === "GET" || body === undefined ? undefined : JSON.stringify(body)
  });

  const raw = await response.text();
  let payload;
  try {
    payload = raw ? JSON.parse(raw) : {};
  } catch (error) {
    payload = {};
  }

  if (!response.ok) {
    const message =
      payload?.message ||
      payload?.error ||
      `Request failed with status ${response.status}`;
    throw new Error(message);
  }

  return payload?.data !== undefined ? payload.data : payload;
}

window.AdminUIAPI = {
  ADMIN_TOKEN_KEY,
  setToken: (token) => localStorage.setItem(ADMIN_TOKEN_KEY, token),
  getToken: () => localStorage.getItem(ADMIN_TOKEN_KEY),
  clearToken: () => localStorage.removeItem(ADMIN_TOKEN_KEY),
  requireToken: () => {
    const token = localStorage.getItem(ADMIN_TOKEN_KEY);
    if (!token) {
      window.location.href = "/ui/admin-login";
      throw new Error("ADMIN_AUTH_MISSING");
    }
    return token;
  },
  login: async ({ username, password }) => {
    const data = await adminFetch("/admin/login", {
      method: "POST",
      auth: false,
      body: { username, password }
    });
    if (data?.token) {
      window.AdminUIAPI.setToken(data.token);
    }
    return data;
  },
  listMerchants: () => adminFetch("/admin/merchants"),
  listOutlets: (query) => adminFetch("/admin/outlets", { query }),
  getOutlet: (id) => adminFetch(`/admin/outlets/${id}`),
  getMerchant: (id) => adminFetch(`/admin/merchants/${id}`),
  patchMerchant: (id, payload) =>
    adminFetch(`/admin/merchants/${id}`, {
      method: "PATCH",
      body: payload
    }),
  approveMerchant: (id) => adminFetch(`/admin/merchants/${id}/approve`, { method: "POST" }),
  rejectMerchant: (id, payload) =>
    adminFetch(`/admin/merchants/${id}/reject`, {
      method: "POST",
      body: payload || {}
    }),
  listTerminals: (query) => adminFetch("/admin/terminals", { query }),
  getTerminal: (id) => adminFetch(`/admin/terminals/${id}`),
  listDevices: (query) => adminFetch("/admin/devices", { query }),
  getDevice: (id) => adminFetch(`/admin/devices/${id}`),
  getDeviceHeartbeats: (id, query) =>
    adminFetch(`/admin/devices/${id}/heartbeats`, { query }),
  getDeviceConfig: (id) => adminFetch(`/admin/devices/${id}/config`),
  getDeviceConfigStatus: (id) => adminFetch(`/admin/devices/${id}/config/status`),
  retryDeviceConfigPush: (id, payload) =>
    adminFetch(`/admin/devices/${id}/config/retry-push`, {
      method: "POST",
      body: payload || {}
    }),
  listTransactions: (query) => adminFetch("/admin/transactions", { query }),
  getDashboardSummary: () => adminFetch("/admin/dashboard/summary"),
  formatMoney,
  formatDateTime
};