/* VMIS Admin Portal - API utilities */

const API = 'http://localhost:10281/api/v1';

/* ── Auth state ── */
let _sysSettings = null;
let _kcInstance  = null;
let _accessToken = null;

/* ── Keycloak SSO guard ── */
async function _loadKcScript(src) {
  return new Promise((resolve) => {
    const s = document.createElement('script');
    s.src = src;
    s.onload = () => resolve(true);
    s.onerror = () => resolve(false);
    document.head.appendChild(s);
  });
}

async function _initKcAuth(settings) {
  // 嘗試路徑順序：新版(Quarkus) → 舊版(WildFly /auth) → CDN
  const candidates = [
    `${settings.keycloak_url}/js/keycloak.js`,
    `${settings.keycloak_url}/auth/js/keycloak.js`,
    'https://cdn.jsdelivr.net/npm/keycloak-js/dist/keycloak.min.js',
  ];
  let loaded = false;
  for (const src of candidates) {
    loaded = await _loadKcScript(src);
    if (loaded) { console.info('KC JS 載入成功：', src); break; }
  }
  if (!loaded) { console.warn('KC JS 全部來源載入失敗，跳過 SSO 守衛'); return; }

  try {
    const kc = new Keycloak({
      url:      settings.keycloak_url,
      realm:    settings.keycloak_realm,
      clientId: settings.keycloak_client || 'vmis-portal',
    });
    const authenticated = await kc.init({
      onLoad:           'login-required',
      pkceMethod:       'S256',
      checkLoginIframe: false,
    });
    if (authenticated) {
      _kcInstance  = kc;
      _accessToken = kc.token;
      setInterval(() => {
        kc.updateToken(60)
          .then(refreshed => { if (refreshed) _accessToken = kc.token; })
          .catch(() => kc.login());
      }, 30000);
      // 在 topbar 插入使用者資訊與登出按鈕
      const topbar = document.getElementById('topbar');
      if (topbar) {
        const username = kc.tokenParsed?.preferred_username || kc.tokenParsed?.name || '';
        const btn = document.createElement('div');
        btn.className = 'ms-3 d-flex align-items-center gap-2';
        btn.innerHTML = `
          <span class="text-muted small"><i class="bi bi-person-circle me-1"></i>${username}</span>
          <button class="btn btn-outline-secondary btn-sm" onclick="_kcInstance.logout()">
            <i class="bi bi-box-arrow-right me-1"></i>登出
          </button>`;
        topbar.appendChild(btn);
      }
    }
  } catch (e) {
    console.error('KC 初始化失敗：', e);
  }
}

/* ── Global settings (loaded on every page) ── */
async function loadSysSettings() {
  try {
    _sysSettings = await apiFetch('/settings');
    // Apply site title: prepend page name if title contains " — "
    if (_sysSettings.site_title) {
      const cur = document.title;
      const sep = cur.indexOf(' — ');
      const pageName = sep >= 0 ? cur.substring(0, sep) : cur;
      document.title = `${pageName} — ${_sysSettings.site_title}`;
    }
    // Inject version badge into topbar if element exists
    const topbar = document.getElementById('topbar');
    if (topbar && _sysSettings.version) {
      const badge = document.createElement('span');
      badge.className = 'badge bg-secondary-subtle text-secondary ms-2';
      badge.textContent = `v${_sysSettings.version}`;
      topbar.querySelector('.fw-semibold')?.after(badge);
    }
    // SSO guard：若已啟用，觸發 Keycloak 認證
    if (_sysSettings.sso_enabled && _sysSettings.keycloak_url && _sysSettings.keycloak_realm) {
      await _initKcAuth(_sysSettings);
    }
  } catch (e) {
    // Silently ignore if settings not yet available
  }
}

// Auto-load on every page
document.addEventListener('DOMContentLoaded', loadSysSettings);

async function apiFetch(path, options = {}) {
  const headers = { 'Content-Type': 'application/json', ...options.headers };
  if (_accessToken) headers['Authorization'] = `Bearer ${_accessToken}`;
  const resp = await fetch(API + path, { headers, ...options });
  if (!resp.ok) {
    // Token 過期 → 重新登入
    if (resp.status === 401 && _kcInstance) { _kcInstance.login(); return; }
    const err = await resp.json().catch(() => ({ detail: resp.statusText }));
    throw Object.assign(new Error(err.detail || resp.statusText), { status: resp.status });
  }
  if (resp.status === 204) return null;
  return resp.json();
}

/* ── light helper ── */
function lightHtml(val) {
  if (val === null || val === undefined) return '<span class="light light-grey" title="無紀錄"></span>';
  return val
    ? '<span class="light light-green" title="正常"></span>'
    : '<span class="light light-red"   title="異常"></span>';
}

/* ── availability color ── */
function availClass(pct) {
  if (pct === null || pct === undefined) return '';
  if (pct >= 99) return '';
  if (pct >= 95) return 'warn';
  return 'danger';
}

function availBar(pct) {
  if (pct === null || pct === undefined) return '<span class="text-muted">—</span>';
  const cls = availClass(pct);
  return `
    <div class="d-flex align-items-center gap-2">
      <div class="avail-bar flex-grow-1">
        <div class="avail-fill ${cls}" style="width:${pct}%"></div>
      </div>
      <small class="${cls === 'danger' ? 'text-danger' : cls === 'warn' ? 'text-warning' : 'text-success'}">${pct}%</small>
    </div>`;
}

/* ── toast ── */
function toast(msg, type = 'success') {
  const container = document.getElementById('toast-container');
  if (!container) return;
  const id = 'toast-' + Date.now();
  const icon = type === 'success' ? '✓' : '✗';
  const bg   = type === 'success' ? 'text-bg-success' : 'text-bg-danger';
  container.insertAdjacentHTML('beforeend', `
    <div id="${id}" class="toast align-items-center ${bg} border-0 show" role="alert">
      <div class="d-flex">
        <div class="toast-body">${icon} ${msg}</div>
        <button type="button" class="btn-close btn-close-white me-2 m-auto" data-bs-dismiss="toast"></button>
      </div>
    </div>`);
  setTimeout(() => document.getElementById(id)?.remove(), 3500);
}

/* ── confirm modal ── */
function confirm(msg) {
  return new Promise(resolve => {
    document.getElementById('confirm-body').textContent = msg;
    const modal = bootstrap.Modal.getOrCreateInstance(document.getElementById('confirmModal'));
    document.getElementById('confirm-ok').onclick = () => { modal.hide(); resolve(true); };
    document.getElementById('confirm-cancel').onclick = () => { modal.hide(); resolve(false); };
    modal.show();
  });
}

/* ── format datetime ── */
// 後端已依設定時區儲存，直接顯示資料庫原始時間，不做轉換
function fmtDt(iso) {
  if (!iso) return '—';
  return iso.replace('T', ' ').substring(0, 19);
}

function fmtDate(iso) {
  if (!iso) return '—';
  return iso.substring(0, 10);
}