/*
 *  Licensed to the Apache Software Foundation (ASF) under one
 *  or more contributor license agreements.  See the NOTICE file
 *  distributed with this work for additional information
 *  regarding copyright ownership.  The ASF 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
 *
 *    https://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.grails.datastore.mapping.core.connections

import groovy.transform.CompileStatic

import org.springframework.core.env.PropertyResolver

/**
 * Models a {@link ConnectionSources} object that only supports a single connection
 *
 * @author Graeme Rocher
 * @since 6.0
 */
@CompileStatic
class SingletonConnectionSources<T, S extends ConnectionSourceSettings> extends AbstractConnectionSources<T, S> {

    SingletonConnectionSources(ConnectionSource<T,S> connectionSource, PropertyResolver configuration) {
        super(connectionSource, new NullConnectionFactory(), configuration)
    }
    @Override
    protected Iterable<String> getConnectionSourceNames(ConnectionSourceFactory<T, S> connectionSourceFactory, PropertyResolver configuration) {
        Arrays.asList(ConnectionSource.DEFAULT)
    }

    @Override
    Iterable<ConnectionSource<T, S>> getAllConnectionSources() {
        return Arrays.asList(defaultConnectionSource)
    }

    @Override
    ConnectionSource<T, S> getConnectionSource(String name) {
        return defaultConnectionSource
    }

    @Override
    ConnectionSource<T, S> addConnectionSource(String name, PropertyResolver configuration) {
        throw new UnsupportedOperationException('Cannot add a connection source it a SingletonConnectionSources')
    }

    static class NullConnectionFactory<T, S extends ConnectionSourceSettings> extends AbstractConnectionSourceFactory<T,S> {

        @Override
        protected <F extends ConnectionSourceSettings> S buildSettings(String name, PropertyResolver configuration, F fallbackSettings, boolean isDefaultDataSource) {
            throw new UnsupportedOperationException('Cannot add a connection source it a SingletonConnectionSources')
        }

        @Override
        ConnectionSource<T, S> create(String name, S settings) {
            throw new UnsupportedOperationException('Cannot add a connection source it a SingletonConnectionSources')
        }

        @Override
        Serializable getConnectionSourcesConfigurationKey() {
            throw new UnsupportedOperationException('Cannot add a connection source it a SingletonConnectionSources')
        }
    }
}
