/*
 * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
 * or more contributor license agreements. Licensed under the "Elastic License
 * 2.0", the "GNU Affero General Public License v3.0 only", and the "Server Side
 * Public License v 1"; you may not use this file except in compliance with, at
 * your election, the "Elastic License 2.0", the "GNU Affero General Public
 * License v3.0 only", or the "Server Side Public License, v 1".
 */

package org.elasticsearch.logstashbridge.geoip;

import org.elasticsearch.cluster.metadata.ProjectId;
import org.elasticsearch.ingest.geoip.IpDatabase;
import org.elasticsearch.ingest.geoip.IpDatabaseProvider;
import org.elasticsearch.logstashbridge.StableBridgeAPI;

/**
 * The {@link AbstractExternalIpDatabaseProviderBridge} is an abstract base class for implementing
 * the {@link IpDatabaseProviderBridge} externally to the Elasticsearch code-base. It takes care of
 * the details of maintaining a singular internal-form implementation of {@link IpDatabaseProvider}
 * that proxies calls to the external implementation.
 */
public abstract class AbstractExternalIpDatabaseProviderBridge implements IpDatabaseProviderBridge {
    private ProxyExternal internalProcessor;

    @Override
    public IpDatabaseProvider toInternal() {
        if (internalProcessor == null) {
            internalProcessor = new ProxyExternal();
        }
        return internalProcessor;
    }

    /**
     * An implementation of {@link IpDatabaseProvider} that proxies calls to
     * a bridged {@link AbstractExternalIpDatabaseProviderBridge} instance.
     */
    private final class ProxyExternal implements IpDatabaseProvider {

        private AbstractExternalIpDatabaseProviderBridge getIpDatabaseProviderBridge() {
            return AbstractExternalIpDatabaseProviderBridge.this;
        }

        @Override
        public Boolean isValid(ProjectId projectId, String name) {
            return AbstractExternalIpDatabaseProviderBridge.this.isValid(name);
        }

        @Override
        public IpDatabase getDatabase(ProjectId projectId, String name) {
            return StableBridgeAPI.toInternalNullable(AbstractExternalIpDatabaseProviderBridge.this.getDatabase(name));
        }
    }
}