/*
 * Copyright 2025 Hirokazu Kobayashi
 *
 * 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 org.idp.server.control_plane.management.oidc.client.handler;

import java.util.HashMap;
import java.util.Map;
import java.util.UUID;
import org.idp.server.control_plane.management.oidc.client.ClientManagementContextBuilder;
import org.idp.server.control_plane.management.oidc.client.io.ClientManagementResponse;
import org.idp.server.control_plane.management.oidc.client.io.ClientManagementStatus;
import org.idp.server.control_plane.management.oidc.client.io.ClientRegistrationRequest;
import org.idp.server.control_plane.management.oidc.client.validator.ClientRegistrationRequestValidator;
import org.idp.server.core.openid.identity.User;
import org.idp.server.core.openid.oauth.configuration.client.ClientConfiguration;
import org.idp.server.core.openid.oauth.configuration.client.ClientConfigurationCommandRepository;
import org.idp.server.core.openid.token.OAuthToken;
import org.idp.server.platform.date.SystemDateTime;
import org.idp.server.platform.json.JsonConverter;
import org.idp.server.platform.multi_tenancy.tenant.Tenant;
import org.idp.server.platform.type.RequestAttributes;

/**
 * Service for client creation operations.
 *
 * <p>Handles business logic for creating client configurations. Part of Handler/Service pattern.
 */
public class ClientCreationService implements ClientManagementService<ClientRegistrationRequest> {

  private final ClientConfigurationCommandRepository commandRepository;
  private final JsonConverter jsonConverter;

  public ClientCreationService(ClientConfigurationCommandRepository commandRepository) {
    this.commandRepository = commandRepository;
    this.jsonConverter = JsonConverter.snakeCaseInstance();
  }

  @Override
  public ClientManagementResponse execute(
      ClientManagementContextBuilder contextBuilder,
      Tenant tenant,
      User operator,
      OAuthToken oAuthToken,
      ClientRegistrationRequest request,
      RequestAttributes requestAttributes,
      boolean dryRun) {

    // Validation
    ClientRegistrationRequestValidator validator =
        new ClientRegistrationRequestValidator(request, dryRun);
    validator.validate(); // throws InvalidRequestException if invalid

    ClientConfiguration clientConfiguration = createClientConfiguration(request);

    // Update context builder with after state
    contextBuilder.withAfter(clientConfiguration);

    Map<String, Object> response = Map.of("result", clientConfiguration.toMap(), "dry_run", dryRun);
    if (dryRun) {

      return new ClientManagementResponse(ClientManagementStatus.CREATED, response);
    }

    // Register client
    commandRepository.register(tenant, clientConfiguration);

    return new ClientManagementResponse(ClientManagementStatus.CREATED, response);
  }

  private ClientConfiguration createClientConfiguration(ClientRegistrationRequest request) {
    // Build ClientConfiguration (add client_id if missing)
    Map<String, Object> map = new HashMap<>(request.toMap());
    if (!request.hasClientId()) {
      map.put("client_id", UUID.randomUUID().toString());
    }
    ClientConfiguration clientConfiguration = jsonConverter.read(map, ClientConfiguration.class);
    clientConfiguration.setCreatedAt(SystemDateTime.now());
    clientConfiguration.setUpdatedAt(SystemDateTime.now());
    return clientConfiguration;
  }
}