/*
 * oauth2-oidc-sdk
 *
 * Copyright 2012-2021, Connect2id Ltd and contributors.
 *
 * 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.oauth2.sdk.dpop.verifiers;


import com.nimbusds.jose.JOSEException;
import com.nimbusds.jose.JWSAlgorithm;
import com.nimbusds.jwt.SignedJWT;
import com.nimbusds.oauth2.sdk.dpop.JWKThumbprintConfirmation;
import com.nimbusds.oauth2.sdk.id.JWTID;
import com.nimbusds.oauth2.sdk.util.Receiver;
import com.nimbusds.oauth2.sdk.util.singleuse.SingleUseChecker;
import com.nimbusds.openid.connect.sdk.Nonce;
import net.jcip.annotations.ThreadSafe;

import java.net.URI;
import java.util.Collections;
import java.util.Map;
import java.util.Objects;
import java.util.Set;


/**
 * DPoP proof JWT verifier for the OAuth 2.0 token endpoint of an authorisation
 * server.
 */
@ThreadSafe
public class DPoPTokenRequestVerifier extends DPoPCommonVerifier {
        
        
        /**
         * The token endpoint URI.
         */
        private final URI endpointURI;
        
        
        /**
         * Creates a new DPoP proof JWT verifier for the OAuth 2.0 token
         * endpoint.
         *
         * @param acceptedJWSAlgs     The accepted JWS algorithms. Must be
         *                            supported and not {@code null}.
         * @param endpointURI         The token endpoint URI. Any query or
         *                            fragment component will be stripped from
         *                            it before performing the comparison. Must
         *                            not be {@code null}.
         * @param maxClockSkewSeconds The maximum permitted DPoP proof "iat"
         *                            clock skew, in seconds. A proof with
         *                            "iat" in the future is accepted if it is
         *                            within this skew tolerance. Intended to
         *                            prevent rejections due to client and
         *                            server system time differences.
         * @param maxAgeSeconds       The maximum accepted DPoP proof "iat" age
         *                            relative to the current system time, in
         *                            seconds. Intended to limit replay by
         *                            bounding how long a proof is valid after
         *                            issue.
         * @param singleUseChecker    The single use checker for the DPoP proof
         *                            "jti" (JWT ID) claims, {@code null} if
         *                            not specified.
         */
        public DPoPTokenRequestVerifier(final Set<JWSAlgorithm> acceptedJWSAlgs,
                                        final URI endpointURI,
                                        final long maxClockSkewSeconds,
                                        final long maxAgeSeconds,
                                        final SingleUseChecker<DPoPProofUse> singleUseChecker) {
                
                super(acceptedJWSAlgs, maxClockSkewSeconds, maxAgeSeconds, singleUseChecker);
                this.endpointURI = Objects.requireNonNull(endpointURI);
        }


        /**
         * Creates a new DPoP proof JWT verifier for the OAuth 2.0 token
         * endpoint.
         *
         * @param acceptedJWSAlgs     The accepted JWS algorithms. Must be
         *                            supported and not {@code null}.
         * @param endpointURI         The token endpoint URI. Any query or
         *                            fragment component will be stripped from
         *                            it before performing the comparison. Must
         *                            not be {@code null}.
         * @param maxClockSkewSeconds The maximum permitted DPoP proof "iat"
         *                            clock skew, in seconds. A proof with
         *                            "iat" in the future is accepted if it is
         *                            within this skew tolerance. Intended to
         *                            prevent rejections due to client and
         *                            server system time differences.
         * @param singleUseChecker    The single use checker for the DPoP proof
         *                            "jti" (JWT ID) claims, {@code null} if
         *                            not specified.
         */
        @Deprecated
        public DPoPTokenRequestVerifier(final Set<JWSAlgorithm> acceptedJWSAlgs,
                                        final URI endpointURI,
                                        final long maxClockSkewSeconds,
                                        final SingleUseChecker<Map.Entry<DPoPIssuer, JWTID>> singleUseChecker) {

                super(acceptedJWSAlgs, maxClockSkewSeconds, singleUseChecker);
                this.endpointURI = Objects.requireNonNull(endpointURI);
        }
        
        
        /**
         * Verifies the specified DPoP proof and returns the DPoP JWK SHA-256
         * thumbprint confirmation.
         *
         * @param issuer Unique identifier for the DPoP proof issuer, typically
         *               as its client ID. Must not be {@code null}.
         * @param proof  The DPoP proof JWT. Must not be {@code null}.
         *
         * @return The DPoP JWK SHA-256 thumbprint confirmation.
         *
         * @throws InvalidDPoPProofException If the DPoP proof is invalid.
         * @throws JOSEException             If an internal JOSE exception is
         *                                   encountered.
         */
        @Deprecated
        public JWKThumbprintConfirmation verify(final DPoPIssuer issuer, final SignedJWT proof)
                throws InvalidDPoPProofException, JOSEException {
                
                return verify(issuer, proof, (Set<Nonce>) null);
        }
        
        
        /**
         * Verifies the specified DPoP proof and returns the DPoP JWK SHA-256
         * thumbprint confirmation.
         *
         * @param issuer Unique identifier for the DPoP proof issuer, typically
         *               as its client ID. Must not be {@code null}.
         * @param proof  The DPoP proof JWT. Must not be {@code null}.
         * @param nonce  The accepted DPoP proof JWT nonce, {@code null} if
         *               none is expected.
         *
         * @return The DPoP JWK SHA-256 thumbprint confirmation.
         *
         * @throws InvalidDPoPProofException If the DPoP proof is invalid.
         * @throws JOSEException             If an internal JOSE exception is
         *                                   encountered.
         */
        public JWKThumbprintConfirmation verify(final DPoPIssuer issuer, final SignedJWT proof, final Nonce nonce)
                throws InvalidDPoPProofException, JOSEException {
                
                return verify(issuer, proof, nonce != null ? Collections.singleton(nonce) : null);
        }


        /**
         * Verifies the specified DPoP proof and returns the DPoP JWK SHA-256
         * thumbprint confirmation.
         *
         * @param issuer Unique identifier for the DPoP proof issuer, typically
         *               a client ID. Must not be {@code null}.
         * @param proof  The DPoP proof JWT. Must not be {@code null}.
         * @param nonces The accepted DPoP proof JWT nonce values, {@code null}
         *               if none are expected.
         *
         * @return The DPoP JWK SHA-256 thumbprint confirmation.
         *
         * @throws InvalidDPoPProofException If the DPoP proof is invalid.
         * @throws JOSEException             If an internal JOSE exception is
         *                                   encountered.
         */
        public JWKThumbprintConfirmation verify(final DPoPIssuer issuer, final SignedJWT proof, final Set<Nonce> nonces)
                throws InvalidDPoPProofException, JOSEException {

                return verify(issuer, proof, nonces, null);
        }


        /**
         * Verifies the specified DPoP proof and returns the DPoP JWK SHA-256
         * thumbprint confirmation.
         *
         * @param issuer      Unique identifier for the DPoP proof issuer,
         *                    typically a client ID. Must not be {@code null}.
         * @param proof       The DPoP proof JWT. Must not be {@code null}.
         * @param nonces      The accepted DPoP proof JWT nonce values,
         *                    {@code null} if none are expected.
         * @param ctxReceiver To access the DPoP proof JWT claims set,
         *                    {@code null} if not required.
         *
         * @return The DPoP JWK SHA-256 thumbprint confirmation.
         *
         * @throws InvalidDPoPProofException If the DPoP proof is invalid.
         * @throws JOSEException             If an internal JOSE exception is
         *                                   encountered.
         */
        public JWKThumbprintConfirmation verify(final DPoPIssuer issuer,
                                                final SignedJWT proof,
                                                final Set<Nonce> nonces,
                                                final Receiver<DPoPProofContext> ctxReceiver)
                throws InvalidDPoPProofException, JOSEException {

                try {
                        super.verify("POST", endpointURI, issuer, proof, null, null, nonces, ctxReceiver);
                } catch (AccessTokenValidationException e) {
                        throw new RuntimeException("Unexpected exception", e);
                }

                return new JWKThumbprintConfirmation(proof.getHeader().getJWK().computeThumbprint());
        }
}