import { MD5 } from '@pura/harmony-utils';
import { WebdavManager } from '../util/WebdavManager';
import FileManager, { merge2paths } from '../util/FileManager';
import { WebDavAccount } from '../../viewmodel/WebDavAccount';
import nativeBridge from 'libentry.so';

interface SmbDownloadBinding {
  downloadSmbFile(host: string, share: string, username: string, password: string, domain: string | undefined, remotePath: string, localPath: string): void;
}

const smbBinding: SmbDownloadBinding = nativeBridge as SmbDownloadBinding;

async function buildCacheFileName(relativePath: string): Promise<string> {
  const hash = await MD5.digestSync(relativePath ?? '');
  const lastSlash = relativePath.lastIndexOf('/');
  const originalName = lastSlash >= 0 ? relativePath.substring(lastSlash + 1) : relativePath;
  const safeName = originalName ? originalName.replace(/[^a-zA-Z0-9_.-]/g, '_') : 'remote';
  return `${hash}_${safeName}`;
}

export async function ensureSmbFileCached(account: WebDavAccount, relativePath: string): Promise<string> {
  const manager = WebdavManager.getInstance();
  if (!manager.context) {
    throw new Error('App context is not initialized');
  }
  if (!account.smbShare) {
    throw new Error('SMB account missing share name');
  }
  const baseDir = manager.context.filesDir ?? manager.context.cacheDir;
  if (!baseDir) {
    throw new Error('Cache directory unavailable');
  }
  const cacheRoot = merge2paths(baseDir, 'smb_cache');
  await FileManager.createDir(cacheRoot);
  const accountDir = merge2paths(cacheRoot, account.id?.toString() ?? 'default');
  await FileManager.createDir(accountDir);
  const normalizedRelative = relativePath?.startsWith('/') ? relativePath : `/${relativePath}`;
  const cacheFileName = await buildCacheFileName(normalizedRelative);
  const localPath = merge2paths(accountDir, cacheFileName);
  let exists = await FileManager.isExist(localPath);
  if (exists) {
    const currentSize = await FileManager.getFileSize(localPath);
    if (currentSize <= 0) {
      await FileManager.deleteFile(localPath);
      exists = false;
    }
  }
  if (!exists) {
    const host = account.isUseLocalHost && account.localHost ? account.localHost : account.host;
    try {
      smbBinding.downloadSmbFile(
        host,
        account.smbShare,
        account.account,
        account.password,
        account.smbDomain,
        normalizedRelative,
        localPath
      );
    } catch (error) {
      await FileManager.deleteFile(localPath);
      const err = error as Error;
      throw err;
    }
  }
  return localPath;
}