/*
 * nimbus-jose-jwt
 *
 * Copyright 2012-2016, Connect2id Ltd.
 *
 * 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
 *
 *    http://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 com.nimbusds.jose;


import net.jcip.annotations.Immutable;

import com.nimbusds.jose.util.Base64URL;

import java.util.List;


/**
 * The cryptographic parts of a JSON Web Encryption (JWE) object.
 *
 * @author Vladimir Dzhuvinov
 * @version 2021-09-30
 */
@Immutable
public final class JWECryptoParts {


        /**
         * The modified JWE header (optional).
         */
        private final JWEHeader header;


        /**
         * The encrypted key (optional).
         */
        private final Base64URL encryptedKey;


        /**
         * The initialisation vector (optional).
         */
        private final Base64URL iv;


        /**
         * The cipher text.
         */
        private final Base64URL cipherText;


        /**
         * The authentication tag (optional).
         */
        private final Base64URL authenticationTag;


        /**
         * The recipients (optional)
         */
        private final List<JWERecipient> recipients;


        /**
         * Creates a new cryptographic JWE parts instance.
         *
         * @param encryptedKey      The encrypted key, {@code null} if not
         *                          required by the encryption algorithm.
         * @param iv                The initialisation vector (IV), 
         *                          {@code null} if not required by the 
         *                          encryption algorithm.
         * @param cipherText        The cipher text. Must not be {@code null}.
         * @param authenticationTag The authentication tag, {@code null} if the
         *                          JWE algorithm provides built-in integrity 
         *                          check.
         */
        public JWECryptoParts(final Base64URL encryptedKey, 
                              final Base64URL iv,
                              final Base64URL cipherText, 
                              final Base64URL authenticationTag) {

                this(null, encryptedKey, iv, cipherText, authenticationTag);
        }


        /**
         * Creates a new cryptographic JWE parts instance.
         *
         * @param header            The modified JWE header, {@code null} if
         *                          not.
         * @param encryptedKey      The encrypted key, {@code null} if not
         *                          required by the encryption algorithm.
         * @param iv                The initialisation vector (IV),
         *                          {@code null} if not required by the
         *                          encryption algorithm.
         * @param cipherText        The cipher text. Must not be {@code null}.
         * @param authenticationTag The authentication tag, {@code null} if the
         *                          JWE algorithm provides built-in integrity
         *                          check.
         */
        public JWECryptoParts(final JWEHeader header,
                              final Base64URL encryptedKey,
                              final Base64URL iv,
                              final Base64URL cipherText,
                              final Base64URL authenticationTag) {

                this.header = header;

                this.encryptedKey = encryptedKey;

                this.iv = iv;

                if (cipherText == null) {

                        throw new IllegalArgumentException("The cipher text must not be null");
                }

                this.cipherText = cipherText;

                this.authenticationTag = authenticationTag;

                this.recipients = null;
        }


        /**
         * Creates a new cryptographic JWE parts instance.
         *
         * @param header            The modified JWE header, {@code null} if
         *                          not.
         * @param recipients        The JWE recipients, {@code null} if not
         *                          required by the encryption algorithm.
         * @param iv                The initialisation vector (IV),
         *                          {@code null} if not required by the
         *                          encryption algorithm.
         * @param cipherText        The cipher text. Must not be {@code null}.
         * @param authenticationTag The authentication tag, {@code null} if the
         *                          JWE algorithm provides built-in integrity
         *                          check.
         */
        public JWECryptoParts(final JWEHeader header,
                              final List<JWERecipient> recipients,
                              final Base64URL iv,
                              final Base64URL cipherText,
                              final Base64URL authenticationTag) {

                this.header = header;

                this.encryptedKey = null;

                this.iv = iv;

                if (cipherText == null) {

                        throw new IllegalArgumentException("The cipher text must not be null");
                }

                this.cipherText = cipherText;

                this.authenticationTag = authenticationTag;

                this.recipients = recipients;
        }


        /**
         * Gets the modified JWE header.
         *
         * @return The modified JWE header, {@code null} of not.
         */
        public JWEHeader getHeader() {

                return header;
        }


        /**
         * Gets the encrypted key.
         *
         * @return The encrypted key, {@code null} if not required by 
         *         the JWE algorithm or {@code recipients} are specified.
         */
        public Base64URL getEncryptedKey() {

                return encryptedKey;
        }


        /**
         * Gets the initialisation vector (IV).
         *
         * @return The initialisation vector (IV), {@code null} if not required
         *         by the JWE algorithm.
         */
        public Base64URL getInitializationVector() {

                return iv;
        }


        /**
         * Gets the cipher text.
         *
         * @return The cipher text.
         */
        public Base64URL getCipherText() {

                return cipherText;
        }


        /**
         * Gets the authentication tag.
         *
         * @return The authentication tag, {@code null} if the encryption
         *         algorithm provides built-in integrity checking.
         */
        public Base64URL getAuthenticationTag() {

                return authenticationTag;
        }
        

        /**
         * Gets the JWE recipients.
         *
         * @return The JWE recipients, {@code null} if not required by the JWE
         *         algorithm or an {@code encryptedKey} is specified.
         */
        public List<JWERecipient> getRecipients() {
                
                return recipients;
        }
}