// Licensed to the Software Freedom Conservancy (SFC) under one
// or more contributor license agreements.  See the NOTICE file
// distributed with this work for additional information
// regarding copyright ownership.  The SFC licenses this file
// to you under the Apache License, Version 2.0 (the
// "License"); you may not use this file except in compliance
// with the License.  You may obtain a copy of the License at
//
//   http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing,
// software distributed under the License is distributed on an
// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
// KIND, either express or implied.  See the License for the
// specific language governing permissions and limitations
// under the License.

package org.openqa.selenium.grid.security;

import org.openqa.selenium.internal.Require;
import org.openqa.selenium.remote.http.Filter;
import org.openqa.selenium.remote.http.HttpHandler;

public class AddSecretFilter implements Filter {

  static final String HEADER_NAME = "X-REGISTRATION-SECRET";
  private final Secret secret;

  public AddSecretFilter(Secret secret) {
    this.secret = Require.nonNull("Secret", secret);
  }

  @Override
  public HttpHandler apply(HttpHandler httpHandler) {
    return req -> {
      if (req.getHeader(HEADER_NAME) == null) {
        req.addHeader(HEADER_NAME, secret.encode());
      }

      return httpHandler.execute(req);
    };
  }
}
