/*
 * Copyright 2023-2024 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.cloud.fn.header.filter;

import java.util.HashSet;
import java.util.Set;

import org.jetbrains.annotations.NotNull;

import org.springframework.integration.IntegrationMessageHeaderAccessor;
import org.springframework.messaging.Message;

public final class HeaderUtils {

	private HeaderUtils() {
	}

	@NotNull
	public static Set<String> getNonReadOnlyHeaders(Message<?> message) {
		var headers = new HashSet<>(message.getHeaders().keySet());
		var accessor = new IntegrationMessageHeaderAccessor(message);
		headers.removeIf(accessor::isReadOnly);
		return headers;
	}

}
