/*
 * Copyright 2013-2024 the original author or authors.
 *
 * 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
 *
 *      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.springframework.data.redis.connection.convert;

import java.util.HashMap;
import java.util.LinkedHashMap;
import java.util.Map;
import java.util.stream.Collectors;

import org.springframework.core.convert.converter.Converter;

/**
 * Converts a Map of values of one key/value type to a Map of values of another type
 *
 * @author Jennifer Hickey
 * @author Christoph Strobl
 * @param <S> The type of keys and values in the Map to convert
 * @param <T> The type of keys and values in the converted Map
 */
public class MapConverter<S, T> implements Converter<Map<S, S>, Map<T, T>> {

	private Converter<S, T> itemConverter;

	/**
	 * @param itemConverter The {@link Converter} to use for converting individual Map keys and values. Must not be
	 *          {@literal null}.
	 */
	public MapConverter(Converter<S, T> itemConverter) {
		this.itemConverter = itemConverter;
	}

	@Override
	public Map<T, T> convert(Map<S, S> source) {

		return source.entrySet().stream() //
				.collect(Collectors.toMap( //
						e -> itemConverter.convert(e.getKey()), //
						e -> itemConverter.convert(e.getValue()), //
						(a, b) -> a, source instanceof LinkedHashMap ? LinkedHashMap::new : HashMap::new));
	}

}
