// Copyright (C) 2013 The Android Open Source Project
//
// Licensed 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 com.google.gerrit.server.restapi.account;

import com.google.common.base.Strings;
import com.google.gerrit.extensions.registration.DynamicItem;
import com.google.gerrit.extensions.restapi.ResourceNotFoundException;
import com.google.gerrit.extensions.restapi.Response;
import com.google.gerrit.extensions.restapi.RestReadView;
import com.google.gerrit.server.account.AccountResource;
import com.google.gerrit.server.avatar.AvatarProvider;
import com.google.inject.Inject;
import com.google.inject.Singleton;

/**
 * REST endpoint to get the URL for changing the avatar image of an account.
 *
 * <p>This REST endpoint handles {@code GET /accounts/<account-identifier>/avatar.change.url}
 * requests.
 *
 * <p>Avatar images are only available if an {@link AvatarProvider} plugin is installed. Not all
 * avatar plugins provide a URL for changing avatar images.
 */
@Singleton
public class GetAvatarChangeUrl implements RestReadView<AccountResource> {
  private final DynamicItem<AvatarProvider> avatarProvider;

  @Inject
  GetAvatarChangeUrl(DynamicItem<AvatarProvider> avatarProvider) {
    this.avatarProvider = avatarProvider;
  }

  @Override
  public Response<String> apply(AccountResource rsrc) throws ResourceNotFoundException {
    AvatarProvider impl = avatarProvider.get();
    if (impl == null) {
      throw new ResourceNotFoundException();
    }

    String url = impl.getChangeAvatarUrl(rsrc.getUser());
    if (Strings.isNullOrEmpty(url)) {
      throw new ResourceNotFoundException();
    }
    return Response.ok(url);
  }
}
