/* app.js - Lagomare Gates frontend */

// ── Token helpers ─────────────────────────────────────────────────────────────
const TOKEN_KEY = "lg_keypass_token";

function saveToken(t) { localStorage.setItem(TOKEN_KEY, t); }
function clearToken() { localStorage.removeItem(TOKEN_KEY); }
function getToken()   { return localStorage.getItem(TOKEN_KEY); }

function tokenValid(t) {
  if (!t) return false;
  try {
    const payload = JSON.parse(atob(t.split(".")[1].replace(/-/g, "+").replace(/_/g, "/")));
    return payload.exp * 1000 > Date.now();
  } catch { return false; }
}

// ── API helper ────────────────────────────────────────────────────────────────
async function apiFetch(method, path, body) {
  const token = getToken();
  const headers = { "Content-Type": "application/json" };
  if (token) headers["Authorization"] = `Bearer ${token}`;
  const res = await fetch(path, {
    method,
    headers,
    body: body !== undefined ? JSON.stringify(body) : undefined,
  });
  if (res.status === 401) {
    clearToken();
    showLogin();
    throw new Error("Session expired or invalid keypass");
  }
  if (!res.ok) {
    const json = await res.json().catch(() => null);
    throw new Error((json && json.detail) || `Error ${res.status}`);
  }
  if (res.status === 204) return null;
  return res.json();
}

// ── Views ─────────────────────────────────────────────────────────────────────
function showLogin() {
  document.getElementById("login-view").classList.remove("hidden");
  document.getElementById("gates-view").classList.add("hidden");
}

function showGatesView() {
  document.getElementById("login-view").classList.add("hidden");
  document.getElementById("gates-view").classList.remove("hidden");
}

// ── Gate rendering ────────────────────────────────────────────────────────────
function renderGates(gates) {
  const grid = document.getElementById("gates-grid");
  const loading = document.getElementById("loading-gates");
  grid.innerHTML = "";

  if (!gates.length) {
    loading.textContent = "No gates configured.";
    loading.classList.remove("hidden");
    grid.classList.add("hidden");
    return;
  }
  loading.classList.add("hidden");
  grid.classList.remove("hidden");

  // Group gates by group_name; null/empty = ungrouped (rendered last, no heading)
  const groups = new Map();
  for (const gate of gates) {
    const key = gate.group_name || "";
    if (!groups.has(key)) groups.set(key, []);
    groups.get(key).push(gate);
  }
  const hasNamedGroups = [...groups.keys()].some(k => k !== "");
  const sortedKeys = [...groups.keys()].sort((a, b) => {
    if (a === "" && b !== "") return 1;
    if (a !== "" && b === "") return -1;
    return a.localeCompare(b);
  });

  for (const key of sortedKeys) {
    const section = document.createElement("div");
    section.className = "gate-group";

    if (hasNamedGroups && key) {
      const title = document.createElement("div");
      title.className = "gate-group-title";
      title.textContent = key;
      section.appendChild(title);
    }

    const groupGrid = document.createElement("div");
    groupGrid.className = "gate-group-grid";

    for (const gate of groups.get(key)) {
      const icon = gate.gate_type === "car" ? "🚘" : "🚶";
      const btn = document.createElement("button");
      btn.className = `gate-btn ${gate.gate_type}`;
      btn.dataset.gateId = gate.id;
      btn.innerHTML = `<span class="icon">${icon}</span><span>${gate.name}</span>`;
      btn.addEventListener("click", () => handleOpenGate(btn, gate));
      groupGrid.appendChild(btn);
    }

    section.appendChild(groupGrid);
    grid.appendChild(section);
  }
}

async function loadGates() {
  try {
    const gates = await apiFetch("GET", "/api/gates");
    renderGates(gates);
  } catch (e) {
    document.getElementById("loading-gates").textContent = e.message;
    document.getElementById("loading-gates").classList.remove("hidden");
  }
}

// ── Open gate action ──────────────────────────────────────────────────────────
let _pendingGate = null;

document.getElementById("confirm-cancel").addEventListener("click", () => {
  document.getElementById("confirm-modal").classList.add("hidden");
  _pendingGate = null;
});
document.getElementById("confirm-ok").addEventListener("click", () => {
  document.getElementById("confirm-modal").classList.add("hidden");
  if (_pendingGate) {
    const { btn, gateId } = _pendingGate;
    _pendingGate = null;
    _doOpenGate(btn, gateId);
  }
});

async function handleOpenGate(btn, gate) {
  _pendingGate = { btn, gateId: gate.id };
  document.getElementById("confirm-gate-name").textContent = gate.name;
  document.getElementById("confirm-modal").classList.remove("hidden");
}

async function _doOpenGate(btn, gateId) {
  btn.disabled = true;
  btn.classList.add("loading");
  btn.classList.remove("ok", "fail");

  try {
    await apiFetch("POST", `/api/gates/${encodeURIComponent(gateId)}/open`);
    btn.classList.remove("loading");
    btn.classList.add("ok");
    showToast("Gate opened ✓", false);
    setTimeout(() => btn.classList.remove("ok"), 2000);
  } catch (e) {
    btn.classList.remove("loading");
    btn.classList.add("fail");
    showToast(e.message, true);
    setTimeout(() => btn.classList.remove("fail"), 2000);
  } finally {
    btn.disabled = false;
  }
}

// ── Toast ─────────────────────────────────────────────────────────────────────
let _toastTimer;
function showToast(msg, isError = false) {
  const el = document.getElementById("toast");
  clearTimeout(_toastTimer);
  el.textContent = msg;
  el.className = `toast ${isError ? "error" : "success"}`;
  _toastTimer = setTimeout(() => el.classList.add("fade"), 2600);
  setTimeout(() => { el.className = "toast hidden"; }, 3000);
}

// ── Login form ────────────────────────────────────────────────────────────────
document.getElementById("login-form").addEventListener("submit", async (e) => {
  e.preventDefault();
  const code = document.getElementById("keypass-input").value.trim();
  if (!code) return;

  const btn = document.getElementById("login-btn");
  const errEl = document.getElementById("login-error");
  btn.disabled = true;
  errEl.classList.add("hidden");

  try {
    const data = await apiFetch("POST", "/api/auth/keypass", { code });
    saveToken(data.token);
    document.getElementById("keypass-input").value = "";
    showGatesView();
    loadGates();
  } catch (e) {
    errEl.textContent = e.message;
    errEl.classList.remove("hidden");
  } finally {
    btn.disabled = false;
  }
});

// ── Logout ────────────────────────────────────────────────────────────────────
document.getElementById("logout-btn").addEventListener("click", () => {
  clearToken();
  showLogin();
});

// ── Init ──────────────────────────────────────────────────────────────────────
(function init() {
  const t = getToken();
  if (tokenValid(t)) {
    showGatesView();
    loadGates();
  } else {
    clearToken();
    showLogin();
  }
})();

// ── Service worker registration ───────────────────────────────────────────────
if ("serviceWorker" in navigator) {
  navigator.serviceWorker.register("/sw.js").catch(() => {});
}

// ── PWA install banner ────────────────────────────────────────────────────────
const INSTALL_DISMISSED_KEY = "lg_install_dismissed";
let _deferredInstallPrompt = null;

window.addEventListener("beforeinstallprompt", (e) => {
  e.preventDefault();
  if (sessionStorage.getItem(INSTALL_DISMISSED_KEY)) return;
  _deferredInstallPrompt = e;
  document.getElementById("install-banner").classList.remove("hidden");
});

document.getElementById("install-btn").addEventListener("click", async () => {
  const banner = document.getElementById("install-banner");
  banner.classList.add("hidden");
  if (!_deferredInstallPrompt) return;
  _deferredInstallPrompt.prompt();
  await _deferredInstallPrompt.userChoice;
  _deferredInstallPrompt = null;
});

document.getElementById("install-dismiss").addEventListener("click", () => {
  document.getElementById("install-banner").classList.add("hidden");
  sessionStorage.setItem(INSTALL_DISMISSED_KEY, "1");
  _deferredInstallPrompt = null;
});

window.addEventListener("appinstalled", () => {
  document.getElementById("install-banner").classList.add("hidden");
  _deferredInstallPrompt = null;
});