/*
 * Copyright 2020-2030 码匠君<herodotus@aliyun.com>
 *
 * Dante Engine 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.
 *
 * Dante Engine 是 Dante Cloud 系统核心组件库，采用 APACHE LICENSE 2.0 开源协议，您在使用过程中，需要注意以下几点：
 *
 * 1. 请不要删除和修改根目录下的LICENSE文件。
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package org.dromara.dante.oauth2.authentication.converter;

import org.apache.commons.lang3.ObjectUtils;
import org.apache.commons.lang3.StringUtils;
import org.apache.commons.lang3.Strings;
import org.dromara.dante.core.constant.SymbolConstants;
import org.dromara.dante.core.constant.SystemConstants;
import org.springframework.core.convert.converter.Converter;
import org.springframework.security.oauth2.server.authorization.AbstractOAuth2ClientRegistration;
import org.springframework.security.oauth2.server.authorization.client.RegisteredClient;
import org.springframework.security.oauth2.server.authorization.settings.ClientSettings;
import org.springframework.security.oauth2.server.authorization.settings.OAuth2TokenFormat;
import org.springframework.security.oauth2.server.authorization.settings.TokenSettings;

/**
 * <p>Description: SAS 客户端注册实体转 {@link RegisteredClient} 转换器抽象定义 </p>
 * <p>
 * 客户端动态注册时，增加自定义属性的扩展处理。
 * <p>
 * 自 Spring Authorization Server 合并至 Spring Security 7.0 后，新增了一个 OAuth2 方式的客户端动态注册。至此 SAS 中就包含 OAuth2 和 OIDC 两种方式的客户端动态注册。
 * 因为，扩展方式相同，所以提取一个抽象类处理公共逻辑。
 *
 * @author : gengwei_zheng
 * @date : 2026/4/27 18:09
 */
abstract class AbstractToRegisteredClientConverter<T extends AbstractOAuth2ClientRegistration> implements Converter<T, RegisteredClient> {

    protected abstract RegisteredClient convertToRegisteredClient(T source);

    @Override
    public RegisteredClient convert(T source) {
        // 先使用 Spring Authorization Server 默认的 XXXRegisteredClientConverter 将 XXXClientRegistration 转换为 RegisteredClient
        // 使用默认的 XXXRegisteredClientConverter 减少转换错误
        RegisteredClient registeredClient = this.convertToRegisteredClient(source);

        // 默认的 XXXRegisteredClientConverter 会设置一些默认值，不好进行修改，使用 from 重新生成一份 RegisteredClient.Builder 以便设定参数。
        RegisteredClient.Builder builder = RegisteredClient.from(registeredClient);

        // 如果指定了 ClientId，则用新值覆盖默认生成的值。
        if (StringUtils.isNotBlank(source.getClientId())) {
            builder.clientId(source.getClientId());
        }

        // 自定义动态注册属性。
        ClientSettings.Builder clientSettingsBuilder = ClientSettings.withSettings(registeredClient.getClientSettings().getSettings());
        TokenSettings.Builder tokenSettingsBuilder = TokenSettings.withSettings(registeredClient.getTokenSettings().getSettings());

        // TokenSettings 的 builder() 方法会将 accessTokenFormat 格式默认设置为 OAuth2TokenFormat.SELF_CONTAINED。这里重新修改为 OAuth2TokenFormat.REFERENCE
        tokenSettingsBuilder.accessTokenFormat(OAuth2TokenFormat.REFERENCE);

        source.getClaims().forEach((claim, value) -> {
            if (Strings.CI.equals(claim, SystemConstants.TOKEN_FORMAT)) {
                tokenSettingsBuilder.accessTokenFormat(parseTokenFormat(value));
            }

            if (Strings.CS.equals(claim, SystemConstants.PARAMETER__PRODUCT_KEY)) {
                // 自定义动态注册属性存入到客户端设置中
                clientSettingsBuilder.setting(claim, value);

                // 如果包含 ProductKey 同时 clientId 为空。那么就重新设置 clientId。物联网 clientId 格式为 {ProductKey}.{DeviceName}
                builder.clientId(value + SymbolConstants.PERIOD + source.getClientName());
            }
        });

        builder.clientSettings(clientSettingsBuilder.build());
        builder.tokenSettings(tokenSettingsBuilder.build());

        return builder.build();
    }

    private OAuth2TokenFormat parseTokenFormat(Object value) {
        if (ObjectUtils.isNotEmpty(value)) {
            String tokenFormat = value.toString();
            if (Strings.CI.equals(tokenFormat, OAuth2TokenFormat.SELF_CONTAINED.getValue())) {
                return OAuth2TokenFormat.SELF_CONTAINED;
            }
        }
        return OAuth2TokenFormat.REFERENCE;
    }
}
