importScripts("zip-no-worker.min.js");

async function writeFile(path, data) {
  const root = await navigator.storage.getDirectory();
  const dir_end = path.lastIndexOf("/");
  const parent = path.substr(0, dir_end);
  const child = path.substr(dir_end+1);
  const parent_dir = await mkdirTree(parent);
  const file = await parent_dir.getFileHandle(child,{create:true});
  const stream = await file.createSyncAccessHandle();
  const written = stream.write(data);
  stream.close();
}

async function mkdirTree(path) {
  const root = await navigator.storage.getDirectory();
  const parts = path.split("/");
  let here = root;
  for (const part of parts) {
    if (part == "") { continue; }
    here = await here.getDirectoryHandle(part, {create:true});
  }
  return here;
}

async function setupZipFS(zipBuf) {
  const root = await navigator.storage.getDirectory();
  const zipReader = new zip.ZipReader(new zip.Uint8ArrayReader(zipBuf), {useWebWorkers:false});
  const entries = await zipReader.getEntries();
  for(const file of entries) {
    if (file.getData && !file.directory) {
      const writer = new zip.Uint8ArrayWriter();
      const data = await file.getData(writer);
      await writeFile(file.filename, data);
    } else if (file.directory) {
      await mkdirTree(file.filename);
    }
  }
  await zipReader.close();
}

onmessage = async (msg) => {
  if(msg.data.command == "load_bundle") {
    let old_timestamp = msg.data.time;
    try {
      const root = await navigator.storage.getDirectory();
      const _bundle = await root.getDirectoryHandle("bundle");
    } catch (_e) {
      old_timestamp = "";
    }
    let resp = await fetch("assets/frontend/bundle-minimal.zip", {
      headers: {
        "If-Modified-Since": old_timestamp
      }
    });
    if (resp.status == 200) {
      await setupZipFS(new Uint8Array(await resp.arrayBuffer()));
    } else {
      await resp.text();
    }
    postMessage({command:"loaded_bundle", time:resp.headers.get("last-modified")});
  } else if(msg.data.command == "upload_file") {
    await writeFile("userdata/content/"+msg.data.name, new Uint8Array(msg.data.data));
    postMessage({command:"uploaded_file",name:msg.data.name});
  }
}