/**
   * If this looks like a POST request (form submission) containing a username and password, give
   * the user the option of saving them. Will either do nothing, or block until the UI interaction
   * is complete.
   *
   * <p>Called by startLoadingResource when using the Apache HTTP stack. Called directly by WebKit
   * when using the Chrome HTTP stack.
   *
   * @param postData The data about to be sent as the body of a POST request.
   * @param username The username entered by the user (sniffed from the DOM).
   * @param password The password entered by the user (sniffed from the DOM).
   */
  private void maybeSavePassword(byte[] postData, String username, String password) {
    if (postData == null
        || username == null
        || username.isEmpty()
        || password == null
        || password.isEmpty()) {
      return; // No password to save.
    }

    if (!mSettings.getSavePassword()) {
      return; // User doesn't want to save passwords.
    }

    try {
      if (DebugFlags.BROWSER_FRAME) {
        Assert.assertNotNull(mCallbackProxy.getBackForwardList().getCurrentItem());
      }
      WebAddress uri =
          new WebAddress(mCallbackProxy.getBackForwardList().getCurrentItem().getUrl());
      String schemePlusHost = uri.getScheme() + uri.getHost();
      // Check to see if the username & password appear in
      // the post data (there could be another form on the
      // page and that was posted instead.
      String postString = new String(postData);
      if (postString.contains(URLEncoder.encode(username))
          && postString.contains(URLEncoder.encode(password))) {
        String[] saved = mDatabase.getUsernamePassword(schemePlusHost);
        if (saved != null) {
          // null username implies that user has chosen not to
          // save password
          if (saved[0] != null) {
            // non-null username implies that user has
            // chosen to save password, so update the
            // recorded password
            mDatabase.setUsernamePassword(schemePlusHost, username, password);
          }
        } else {
          // CallbackProxy will handle creating the resume
          // message
          mCallbackProxy.onSavePassword(schemePlusHost, username, password, null);
        }
      }
    } catch (ParseException ex) {
      // if it is bad uri, don't save its password
    }
  }
  /**
   * Handle messages posted to us.
   *
   * @param msg The message to handle.
   */
  @Override
  public void handleMessage(Message msg) {
    if (mBlockMessages) {
      return;
    }
    switch (msg.what) {
      case FRAME_COMPLETED:
        {
          if (mSettings.getSavePassword() && hasPasswordField()) {
            WebHistoryItem item = mCallbackProxy.getBackForwardList().getCurrentItem();
            if (item != null) {
              WebAddress uri = new WebAddress(item.getUrl());
              String schemePlusHost = uri.getScheme() + uri.getHost();
              String[] up = mDatabase.getUsernamePassword(schemePlusHost);
              if (up != null && up[0] != null) {
                setUsernamePassword(up[0], up[1]);
              }
            }
          }
          if (!JniUtil.useChromiumHttpStack()) {
            WebViewWorker.getHandler().sendEmptyMessage(WebViewWorker.MSG_TRIM_CACHE);
          }
          break;
        }

      case POLICY_FUNCTION:
        {
          nativeCallPolicyFunction(msg.arg1, msg.arg2);
          break;
        }

      case ORIENTATION_CHANGED:
        {
          if (mOrientation != msg.arg1) {
            mOrientation = msg.arg1;
            nativeOrientationChanged(msg.arg1);
          }
          break;
        }

      default:
        break;
    }
  }