/*
 * Copyright 2004-present 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.security.web.webauthn.api;

import java.util.Arrays;
import java.util.List;

import org.jspecify.annotations.Nullable;

/**
 * <a href=
 * "https://www.w3.org/TR/webauthn-3/#authenticatorattestationresponse">AuthenticatorAttestationResponse</a>
 * represents the
 * <a href="https://www.w3.org/TR/webauthn-3/#authenticator">authenticator</a>'s response
 * to a client's request for the creation of a new
 * <a href="https://www.w3.org/TR/webauthn-3/#public-key-credential">public key
 * credential</a>.
 *
 * @author Rob Winch
 * @since 6.4
 * @see PublicKeyCredential#getResponse()
 */
public final class AuthenticatorAttestationResponse extends AuthenticatorResponse {

	private final Bytes attestationObject;

	private final @Nullable List<AuthenticatorTransport> transports;

	private AuthenticatorAttestationResponse(Bytes clientDataJSON, Bytes attestationObject,
			@Nullable List<AuthenticatorTransport> transports) {
		super(clientDataJSON);
		this.attestationObject = attestationObject;
		this.transports = transports;
	}

	/**
	 * The <a href=
	 * "https://www.w3.org/TR/webauthn-3/#dom-authenticatorattestationresponse-attestationobject">attestationObject</a>
	 * attribute contains an attestation object, which is opaque to, and cryptographically
	 * protected against tampering by, the client.
	 * @return the attestationObject
	 */
	public Bytes getAttestationObject() {
		return this.attestationObject;
	}

	/**
	 * The <a href=
	 * "https://www.w3.org/TR/webauthn-3/#dom-authenticatorattestationresponse-gettransports">transports</a>
	 * returns the <a href=
	 * "https://www.w3.org/TR/webauthn-3/#dom-authenticatorattestationresponse-transports-slot">transports</a>
	 * @return the transports
	 */
	public @Nullable List<AuthenticatorTransport> getTransports() {
		return this.transports;
	}

	/**
	 * Creates a new instance.
	 * @return the {@link AuthenticatorAttestationResponseBuilder}
	 */
	public static AuthenticatorAttestationResponseBuilder builder() {
		return new AuthenticatorAttestationResponseBuilder();
	}

	/**
	 * Builds {@link AuthenticatorAssertionResponse}.
	 *
	 * @author Rob Winch
	 * @since 6.4
	 */
	public static final class AuthenticatorAttestationResponseBuilder {

		@SuppressWarnings("NullAway.Init")
		private Bytes attestationObject;

		private @Nullable List<AuthenticatorTransport> transports;

		@SuppressWarnings("NullAway.Init")
		private Bytes clientDataJSON;

		private AuthenticatorAttestationResponseBuilder() {
		}

		/**
		 * Sets the {@link #getAttestationObject()} property.
		 * @param attestationObject the attestation object.
		 * @return the {@link AuthenticatorAttestationResponseBuilder}
		 */
		public AuthenticatorAttestationResponseBuilder attestationObject(Bytes attestationObject) {
			this.attestationObject = attestationObject;
			return this;
		}

		/**
		 * Sets the {@link #getTransports()} property.
		 * @param transports the transports
		 * @return the {@link AuthenticatorAttestationResponseBuilder}
		 */
		public AuthenticatorAttestationResponseBuilder transports(AuthenticatorTransport... transports) {
			return transports(Arrays.asList(transports));
		}

		/**
		 * Sets the {@link #getTransports()} property.
		 * @param transports the transports
		 * @return the {@link AuthenticatorAttestationResponseBuilder}
		 */
		public AuthenticatorAttestationResponseBuilder transports(List<AuthenticatorTransport> transports) {
			this.transports = transports;
			return this;
		}

		/**
		 * Sets the {@link #getClientDataJSON()} property.
		 * @param clientDataJSON the client data JSON.
		 * @return the {@link AuthenticatorAttestationResponseBuilder}
		 */
		public AuthenticatorAttestationResponseBuilder clientDataJSON(Bytes clientDataJSON) {
			this.clientDataJSON = clientDataJSON;
			return this;
		}

		/**
		 * Builds a {@link AuthenticatorAssertionResponse}.
		 * @return the {@link AuthenticatorAttestationResponseBuilder}
		 */
		public AuthenticatorAttestationResponse build() {
			return new AuthenticatorAttestationResponse(this.clientDataJSON, this.attestationObject, this.transports);
		}

	}

}
