/**
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements. See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership. The ASF licenses this file
 * to you 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 org.apache.cxf.systest.jaxrs.security.oidc;

import java.io.IOException;
import java.net.URL;
import java.security.KeyStore;
import java.security.KeyStoreException;
import java.security.NoSuchAlgorithmException;
import java.security.PrivateKey;
import java.security.cert.Certificate;
import java.security.cert.CertificateException;
import java.security.cert.X509Certificate;

import javax.ws.rs.core.Response;

import org.apache.cxf.common.classloader.ClassLoaderUtils;
import org.apache.cxf.jaxrs.client.WebClient;
import org.apache.cxf.rs.security.jose.jwa.SignatureAlgorithm;
import org.apache.cxf.rs.security.jose.jwe.JweJwtCompactConsumer;
import org.apache.cxf.rs.security.jose.jws.JwsJwtCompactConsumer;
import org.apache.cxf.rs.security.jose.jwt.JwtConstants;
import org.apache.cxf.rs.security.jose.jwt.JwtToken;
import org.apache.cxf.rs.security.oauth2.common.ClientAccessToken;
import org.apache.cxf.rs.security.oidc.common.IdToken;
import org.apache.cxf.rs.security.oidc.common.UserInfo;
import org.apache.cxf.systest.jaxrs.security.oauth2.common.OAuth2TestUtils;
import org.apache.cxf.testutil.common.AbstractBusClientServerTestBase;
import org.apache.cxf.testutil.common.TestUtil;

import org.junit.Assert;
import org.junit.BeforeClass;

/**
 * Some unit tests for the UserInfo Service in OpenId Connect. This can be used to return the User's claims given
 * an access token.
 */
public class UserInfoTest extends AbstractBusClientServerTestBase {

    static final String PORT = TestUtil.getPortNumber("jaxrs-userinfo");

    @BeforeClass
    public static void startServers() throws Exception {
        assertTrue(
                "Server failed to launch",
                // run the server in the same process
                // set this to false to fork
                launchServer(UserInfoServer.class, true)
        );
    }

    @org.junit.Test
    public void testPlainUserInfo() throws Exception {
        URL busFile = UserInfoTest.class.getResource("client.xml");

        String address = "https://localhost:" + PORT + "/services/oidc";
        WebClient client = WebClient.create(address, OAuth2TestUtils.setupProviders(),
                                            "alice", "security", busFile.toString());

        // Save the Cookie for the second request...
        WebClient.getConfig(client).getRequestContext().put(
            org.apache.cxf.message.Message.MAINTAIN_SESSION, Boolean.TRUE);

        // Get Authorization Code
        String code = OAuth2TestUtils.getAuthorizationCode(client, "openid");
        assertNotNull(code);

        // Now get the access token
        client = WebClient.create(address, OAuth2TestUtils.setupProviders(),
                                  "consumer-id", "this-is-a-secret", busFile.toString());
        // Save the Cookie for the second request...
        WebClient.getConfig(client).getRequestContext().put(
            org.apache.cxf.message.Message.MAINTAIN_SESSION, Boolean.TRUE);

        ClientAccessToken accessToken =
            OAuth2TestUtils.getAccessTokenWithAuthorizationCode(client, code);
        assertNotNull(accessToken.getTokenKey());
        assertTrue(accessToken.getApprovedScope().contains("openid"));

        String idToken = accessToken.getParameters().get("id_token");
        assertNotNull(idToken);
        validateIdToken(idToken, null);

        // Now invoke on the UserInfo service with the access token
        String userInfoAddress = "https://localhost:" + PORT + "/services/plain/userinfo";
        WebClient userInfoClient = WebClient.create(userInfoAddress, OAuth2TestUtils.setupProviders(),
                                                    busFile.toString());
        userInfoClient.accept("application/json");
        userInfoClient.header("Authorization", "Bearer " + accessToken.getTokenKey());

        Response serviceResponse = userInfoClient.get();
        assertEquals(serviceResponse.getStatus(), 200);

        UserInfo userInfo = serviceResponse.readEntity(UserInfo.class);
        assertNotNull(userInfo);

        assertEquals("alice", userInfo.getSubject());
        assertEquals("consumer-id", userInfo.getAudience());
    }

    @org.junit.Test
    public void testSignedUserInfo() throws Exception {
        URL busFile = UserInfoTest.class.getResource("client.xml");

        String address = "https://localhost:" + PORT + "/services/oidc";
        WebClient client = WebClient.create(address, OAuth2TestUtils.setupProviders(),
                                            "alice", "security", busFile.toString());

        // Save the Cookie for the second request...
        WebClient.getConfig(client).getRequestContext().put(
            org.apache.cxf.message.Message.MAINTAIN_SESSION, Boolean.TRUE);

        // Get Authorization Code
        String code = OAuth2TestUtils.getAuthorizationCode(client, "openid");
        assertNotNull(code);

        // Now get the access token
        client = WebClient.create(address, OAuth2TestUtils.setupProviders(),
                                  "consumer-id", "this-is-a-secret", busFile.toString());
        // Save the Cookie for the second request...
        WebClient.getConfig(client).getRequestContext().put(
            org.apache.cxf.message.Message.MAINTAIN_SESSION, Boolean.TRUE);

        ClientAccessToken accessToken =
            OAuth2TestUtils.getAccessTokenWithAuthorizationCode(client, code);
        assertNotNull(accessToken.getTokenKey());
        assertTrue(accessToken.getApprovedScope().contains("openid"));

        String idToken = accessToken.getParameters().get("id_token");
        assertNotNull(idToken);
        validateIdToken(idToken, null);

        // Now invoke on the UserInfo service with the access token
        String userInfoAddress = "https://localhost:" + PORT + "/services/signed/userinfo";
        WebClient userInfoClient = WebClient.create(userInfoAddress, OAuth2TestUtils.setupProviders(),
                                                    busFile.toString());
        userInfoClient.accept("application/jwt");
        userInfoClient.header("Authorization", "Bearer " + accessToken.getTokenKey());

        Response serviceResponse = userInfoClient.get();
        assertEquals(serviceResponse.getStatus(), 200);

        String token = serviceResponse.readEntity(String.class);
        assertNotNull(token);

        JwsJwtCompactConsumer jwtConsumer = new JwsJwtCompactConsumer(token);
        JwtToken jwt = jwtConsumer.getJwtToken();

        assertEquals("alice", jwt.getClaim(JwtConstants.CLAIM_SUBJECT));
        assertEquals("consumer-id", jwt.getClaim(JwtConstants.CLAIM_AUDIENCE));

        KeyStore keystore = KeyStore.getInstance("JKS");
        keystore.load(ClassLoaderUtils.getResourceAsStream("keys/alice.jks", this.getClass()),
                      "password".toCharArray());
        Certificate cert = keystore.getCertificate("alice");
        Assert.assertNotNull(cert);

        Assert.assertTrue(jwtConsumer.verifySignatureWith((X509Certificate)cert,
                                                          SignatureAlgorithm.RS256));
    }

    @org.junit.Test
    public void testEncryptedUserInfo() throws Exception {
        URL busFile = UserInfoTest.class.getResource("client.xml");

        String address = "https://localhost:" + PORT + "/services/oidc";
        WebClient client = WebClient.create(address, OAuth2TestUtils.setupProviders(),
                                            "alice", "security", busFile.toString());

        // Save the Cookie for the second request...
        WebClient.getConfig(client).getRequestContext().put(
            org.apache.cxf.message.Message.MAINTAIN_SESSION, Boolean.TRUE);

        // Get Authorization Code
        String code = OAuth2TestUtils.getAuthorizationCode(client, "openid");
        assertNotNull(code);

        // Now get the access token
        client = WebClient.create(address, OAuth2TestUtils.setupProviders(),
                                  "consumer-id", "this-is-a-secret", busFile.toString());
        // Save the Cookie for the second request...
        WebClient.getConfig(client).getRequestContext().put(
            org.apache.cxf.message.Message.MAINTAIN_SESSION, Boolean.TRUE);

        ClientAccessToken accessToken =
            OAuth2TestUtils.getAccessTokenWithAuthorizationCode(client, code);
        assertNotNull(accessToken.getTokenKey());
        assertTrue(accessToken.getApprovedScope().contains("openid"));

        String idToken = accessToken.getParameters().get("id_token");
        assertNotNull(idToken);
        validateIdToken(idToken, null);

        // Now invoke on the UserInfo service with the access token
        String userInfoAddress = "https://localhost:" + PORT + "/services/encrypted/userinfo";
        WebClient userInfoClient = WebClient.create(userInfoAddress, OAuth2TestUtils.setupProviders(),
                                                    busFile.toString());
        userInfoClient.accept("application/jwt");
        userInfoClient.header("Authorization", "Bearer " + accessToken.getTokenKey());

        Response serviceResponse = userInfoClient.get();
        assertEquals(200, serviceResponse.getStatus());

        String token = serviceResponse.readEntity(String.class);
        assertNotNull(token);

        KeyStore keystore = KeyStore.getInstance("JKS");
        keystore.load(ClassLoaderUtils.getResourceAsStream("keys/bob.jks", this.getClass()),
                      "password".toCharArray());

        JweJwtCompactConsumer jwtConsumer = new JweJwtCompactConsumer(token);
        PrivateKey privateKey = (PrivateKey)keystore.getKey("bob", "password".toCharArray());
        JwtToken jwt = jwtConsumer.decryptWith(privateKey);

        assertEquals("alice", jwt.getClaim(JwtConstants.CLAIM_SUBJECT));
        assertEquals("consumer-id", jwt.getClaim(JwtConstants.CLAIM_AUDIENCE));
    }

    private void validateIdToken(String idToken, String nonce)
        throws KeyStoreException, NoSuchAlgorithmException, CertificateException, IOException {
        JwsJwtCompactConsumer jwtConsumer = new JwsJwtCompactConsumer(idToken);
        JwtToken jwt = jwtConsumer.getJwtToken();

        // Validate claims
        Assert.assertEquals("alice", jwt.getClaim(JwtConstants.CLAIM_SUBJECT));
        Assert.assertEquals("OIDC IdP", jwt.getClaim(JwtConstants.CLAIM_ISSUER));
        Assert.assertEquals("consumer-id", jwt.getClaim(JwtConstants.CLAIM_AUDIENCE));
        Assert.assertNotNull(jwt.getClaim(JwtConstants.CLAIM_EXPIRY));
        Assert.assertNotNull(jwt.getClaim(JwtConstants.CLAIM_ISSUED_AT));
        if (nonce != null) {
            Assert.assertEquals(nonce, jwt.getClaim(IdToken.NONCE_CLAIM));
        }

        KeyStore keystore = KeyStore.getInstance("JKS");
        keystore.load(ClassLoaderUtils.getResourceAsStream("keys/alice.jks", this.getClass()),
                      "password".toCharArray());
        Certificate cert = keystore.getCertificate("alice");
        Assert.assertNotNull(cert);

        Assert.assertTrue(jwtConsumer.verifySignatureWith((X509Certificate)cert,
                                                          SignatureAlgorithm.RS256));
    }
}
