// ================================================
// SGE — B2 Client
// Proxy: /b2proxy (Flask pe HuggingFace)
// ================================================

const PROXY = '/b2proxy';

async function proxyCall(action, path, extraHeaders = {}, body = null) {
  const opts = {
    method: 'POST',
    headers: {
      'X-Action': action,
      'X-Path':   path,
      ...extraHeaders
    }
  };
  if (body) opts.body = body;

  const res = await fetch(PROXY, opts);
  if (!res.ok) {
    const txt = await res.text();
    throw new Error(txt || `err-027 — HTTP ${res.status}`);
  }
  return res.json();
}

// ── UPLOAD (prin proxy Flask — fara CORS issues) ──
async function b2Upload(file, path, onProgress) {
  // Citeste fisierul
  const buf  = await file.arrayBuffer();

  // SHA1 pentru integritate
  const hash = await crypto.subtle.digest('SHA-1', buf);
  const sha1 = Array.from(new Uint8Array(hash))
    .map(b => b.toString(16).padStart(2, '0')).join('');

  // Upload prin proxy (Flask il trimite mai departe la B2)
  // Folosim XMLHttpRequest pentru progress
  return new Promise((resolve, reject) => {
    const xhr = new XMLHttpRequest();
    xhr.open('POST', PROXY);
    xhr.setRequestHeader('X-Action',       'upload');
    xhr.setRequestHeader('X-Path',         path);
    xhr.setRequestHeader('X-Content-Type', file.type || 'application/octet-stream');
    xhr.setRequestHeader('X-Sha1',         sha1);
    xhr.setRequestHeader('Content-Type',   'application/octet-stream');

    xhr.upload.onprogress = e => {
      if (e.lengthComputable && onProgress)
        onProgress(Math.round(e.loaded / e.total * 100));
    };

    xhr.onload = () => {
      if (xhr.status === 200) {
        resolve(path);
      } else {
        reject(new Error(`err-009 — Upload esuat: ${xhr.status}`));
      }
    };
    xhr.onerror = () => reject(new Error('err-027 — Eroare retea la upload'));
    xhr.send(buf);
  });
}

// ── LIST ──
async function b2List(prefix) {
  try {
    const data = await proxyCall('list', prefix);
    return data.files || [];
  } catch(e) {
    console.error('b2List:', e.message);
    return [];
  }
}

// ── DELETE ──
async function b2Delete(key) {
  try {
    await proxyCall('delete', key);
  } catch(e) {
    console.error('b2Delete:', e.message);
  }
}