'use strict';

// ---------------------------------------------------------------------------
// "Eingang" (docs/library.md): a cloud source marked so brings its new books into the
// library by itself. When the library loads, the server says which files of such sources
// no device has taken yet (and keeps them for this device ten minutes); each is fetched
// through the server, encrypted here like any import, uploaded, and reported done. A book
// already in the library (same title and author) is left out. The folder stays as it is.
// Only where the book key is there; not in diora Reader (e-readers: battery, weak Wi-Fi).
// ---------------------------------------------------------------------------

const CLOUD_INBOX_EVERY_MS = 5 * 60 * 1000;
let _cloudInboxBusy = false;
let _cloudInboxLast = 0;

function _cloudInboxKeyReady() {
  // getOrCreateEncKey() would make a new key when there is none: never import without the real one.
  try { return !!localStorage.getItem(`diora_enc_key_${window.USER_ID || 0}`); } catch (e) { return false; }
}

async function cloudInboxCheck(force) {
  if (typeof IS_AUTHENTICATED === 'undefined' || !IS_AUTHENTICATED) return;
  if (document.documentElement.classList.contains('nui-reader-app')) return;
  if (_cloudInboxBusy || !_cloudInboxKeyReady()) return;
  if (!force && Date.now() - _cloudInboxLast < CLOUD_INBOX_EVERY_MS) return;
  _cloudInboxBusy = true;
  _cloudInboxLast = Date.now();
  const statusEl = $('book-upload-status');
  const taken = [];
  try {
    const r = await fetch('/books/cloud/inbox/', {cache: 'no-store'});
    if (!r.ok) return;
    const files = (await r.json()).files || [];
    for (let i = 0; i < files.length; i++) {
      const f = files[i];
      if (statusEl) statusEl.textContent = `Eingang „${f.label}“: ${i + 1} von ${files.length} – ${f.name} …`;
      let result = 'failed';
      try {
        if (f.size > DIORA_CONFIG.ebookMaxBytes) {
          result = 'too_big';
        } else {
          const res = await fetch(`/books/cloud/${f.source}/fetch/?path=${encodeURIComponent(f.path)}`);
          if (res.ok) {
            const out = await _importEbookBuffer(await res.arrayBuffer(), f.name, null, {reload: false, skipKnown: true});
            result = out === 'dup' ? 'known' : out ? 'imported' : 'failed';
          }
        }
      } catch (e) {
        result = 'failed';
      }
      if (result === 'imported') taken.push(f);
      await fetch(`/books/cloud/${f.source}/done/`, {
        method: 'POST', headers: {'Content-Type': 'application/json'},
        body: JSON.stringify({path: f.path, result}),
      }).catch(() => {});
    }
  } catch (e) {
    // Offline or the source unreachable: next time.
  } finally {
    _cloudInboxBusy = false;
  }
  if (statusEl) {
    const labels = [...new Set(taken.map(f => f.label))].map(l => `„${l}“`).join(', ');
    statusEl.textContent = taken.length
      ? `${taken.length === 1 ? 'Ein neues Buch' : taken.length + ' neue Bücher'} aus ${labels} übernommen.` : '';
  }
  if (taken.length) loadBookList();
}

// After the list has loaded (and the key is known), quietly look into the inboxes.
(function () {
  const orig = window.loadBookList;
  if (typeof orig !== 'function') return;
  window.loadBookList = async function () {
    const out = await orig.apply(this, arguments);
    setTimeout(() => cloudInboxCheck(false), 1500);
    return out;
  };
})();