/*
 * Copyright 2002-2022 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.web.server;

import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpStatusCode;
import org.springframework.http.ProblemDetail;
import org.springframework.lang.Nullable;
import org.springframework.web.ErrorResponseException;

/**
 * Subclass of {@link ErrorResponseException} that accepts a "reason", and by
 * default maps that to the {@link ErrorResponseException#setDetail(String) "detail"}
 * of the {@code ProblemDetail}.
 *
 * @author Rossen Stoyanchev
 * @author Juergen Hoeller
 * @since 5.0
 */
@SuppressWarnings("serial")
public class ResponseStatusException extends ErrorResponseException {

	@Nullable
	private final String reason;


	/**
	 * Constructor with a response status.
	 * @param status the HTTP status (required)
	 */
	public ResponseStatusException(HttpStatusCode status) {
		this(status, null);
	}

	/**
	 * Constructor with a response status and a reason to add to the exception
	 * message as explanation.
	 * @param status the HTTP status (required)
	 * @param reason the associated reason (optional)
	 */
	public ResponseStatusException(HttpStatusCode status, @Nullable String reason) {
		this(status, reason, null);
	}

	/**
	 * Constructor with a response status and a reason to add to the exception
	 * message as explanation, as well as a nested exception.
	 * @param rawStatusCode the HTTP status code value
	 * @param reason the associated reason (optional)
	 * @param cause a nested exception (optional)
	 * @since 5.3
	 */
	public ResponseStatusException(int rawStatusCode, @Nullable String reason, @Nullable Throwable cause) {
		this(HttpStatusCode.valueOf(rawStatusCode), reason, cause);
	}

	/**
	 * Constructor with a response status and a reason to add to the exception
	 * message as explanation, as well as a nested exception.
	 * @param status the HTTP status (required)
	 * @param reason the associated reason (optional)
	 * @param cause a nested exception (optional)
	 */
	public ResponseStatusException(HttpStatusCode status, @Nullable String reason, @Nullable Throwable cause) {
		this(status, reason, cause, null, null);
	}

	/**
	 * Constructor with a message code and arguments for resolving the error
	 * "detail" via {@link org.springframework.context.MessageSource}.
	 * @param status the HTTP status (required)
	 * @param reason the associated reason (optional)
	 * @param cause a nested exception (optional)
	 * @since 6.0
	 */
	protected ResponseStatusException(
			HttpStatusCode status, @Nullable String reason, @Nullable Throwable cause,
			@Nullable String messageDetailCode, @Nullable Object[] messageDetailArguments) {

		super(status, ProblemDetail.forStatus(status), cause, messageDetailCode, messageDetailArguments);
		this.reason = reason;
		setDetail(reason);
	}


	/**
	 * The reason explaining the exception (potentially {@code null} or empty).
	 */
	@Nullable
	public String getReason() {
		return this.reason;
	}

	/**
	 * Return headers to add to the error response, e.g. "Allow", "Accept", etc.
	 * <p>By default, delegates to {@link #getResponseHeaders()} for backwards
	 * compatibility.
	 */
	@Override
	public HttpHeaders getHeaders() {
		return getResponseHeaders();
	}

	/**
	 * Return headers associated with the exception that should be added to the
	 * error response, e.g. "Allow", "Accept", etc.
	 * <p>The default implementation in this class returns empty headers.
	 * @since 5.1.13
	 * @deprecated as of 6.0 in favor of {@link #getHeaders()}
	 */
	@Deprecated(since = "6.0")
	public HttpHeaders getResponseHeaders() {
		return HttpHeaders.EMPTY;
	}

	@Override
	public String getMessage() {
		return getStatusCode() + (this.reason != null ? " \"" + this.reason + "\"" : "");
	}

}
