/**
 * ─────────────────────────────────────────────
 *  SPB Drive — Personal Cloud Drive
 * ─────────────────────────────────────────────
 *  Author  : Simon-Pierre Boucher
 *  Contact : contact@spboucher.ai
 *  File    : src/web/assets/js/request-page.js
 *  Purpose : Public file-request page — chunked uploads from strangers
 *  License : MIT © Simon-Pierre Boucher
 * ─────────────────────────────────────────────
 */

import { h, fmtSize, toast } from './ui.js';

const page = document.querySelector('.share-page');
const token = page.dataset.token;
const maxFiles = page.dataset.maxFiles ? Number(page.dataset.maxFiles) : null;
let uploadedCount = Number(page.dataset.received || 0);

const drop = document.getElementById('requestDrop');
const list = document.getElementById('requestList');
const pick = document.getElementById('requestPick');

const base = `/r/${encodeURIComponent(token)}`;

async function jsonOrThrow(res) {
  const data = res.headers.get('content-type')?.includes('json') ? await res.json() : null;
  if (!res.ok) throw new Error(data?.error?.message ?? `HTTP ${res.status}`);
  return data;
}

async function uploadFile(file) {
  if (maxFiles !== null && uploadedCount >= maxFiles) {
    toast('This link has reached its file limit', { error: true });
    return;
  }
  const row = h('div.upload-item', {},
    h('div.fname', {},
      h('span.n', {}, file.name),
      h('span.s', {}, 'Starting…'),
      h('div.prog', {}, h('i'))));
  list.append(row);
  const setStatus = (text) => { row.querySelector('.s').textContent = text; };
  const setPct = (pct) => { row.querySelector('.prog i').style.width = `${pct}%`; };

  try {
    const init = await jsonOrThrow(await fetch(`${base}/upload/init`, {
      method: 'POST',
      headers: { 'content-type': 'application/json' },
      body: JSON.stringify({ name: file.name, size: file.size }),
    }));
    const { uploadId, chunkSize, nChunks } = init;
    for (let n = 0; n < nChunks; n += 1) {
      const slice = file.slice(n * chunkSize, Math.min((n + 1) * chunkSize, file.size));
      let attempt = 0;
      for (;;) {
        try {
          const res = await fetch(`${base}/upload/${uploadId}/chunk/${n}`, {
            method: 'PUT',
            headers: { 'content-type': 'application/octet-stream' },
            body: slice,
          });
          if (!res.ok) throw new Error(`HTTP ${res.status}`);
          break;
        } catch (err) {
          attempt += 1;
          if (attempt > 3) throw err;
          await new Promise((r) => setTimeout(r, 1000 * attempt));
        }
      }
      const sent = Math.min((n + 1) * chunkSize, file.size);
      setPct(file.size ? (sent / file.size) * 100 : 100);
      setStatus(`${fmtSize(sent)} / ${fmtSize(file.size)}`);
    }
    const done = await jsonOrThrow(await fetch(`${base}/upload/${uploadId}/complete`, {
      method: 'POST',
      headers: { 'content-type': 'application/json' },
      body: JSON.stringify({ mime: file.type || undefined }),
    }));
    uploadedCount += 1;
    row.classList.add('done');
    setPct(100);
    setStatus(`Sent · ${done.name}`);
  } catch (err) {
    row.classList.add('err');
    setStatus(`Failed — ${err.message}`);
  }
}

async function handleFiles(files) {
  const queue = [...files];
  if (!queue.length) return;
  if (maxFiles !== null && uploadedCount + queue.length > maxFiles) {
    toast(`Only ${Math.max(0, maxFiles - uploadedCount)} more file(s) allowed on this link`, { error: true });
    queue.length = Math.max(0, maxFiles - uploadedCount);
  }
  for (const file of queue) await uploadFile(file);
}

drop.addEventListener('click', () => pick.click());
drop.addEventListener('keydown', (e) => { if (e.key === 'Enter' || e.key === ' ') { e.preventDefault(); pick.click(); } });
pick.addEventListener('change', (e) => { handleFiles(e.target.files); e.target.value = ''; });

for (const ev of ['dragenter', 'dragover']) {
  drop.addEventListener(ev, (e) => { e.preventDefault(); drop.classList.add('active'); });
}
for (const ev of ['dragleave', 'drop']) {
  drop.addEventListener(ev, (e) => { e.preventDefault(); drop.classList.remove('active'); });
}
drop.addEventListener('drop', (e) => handleFiles(e.dataTransfer?.files ?? []));