/*
 * 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.fineract.cn.anubis.token;

import io.jsonwebtoken.Claims;
import io.jsonwebtoken.Header;
import io.jsonwebtoken.Jwt;
import io.jsonwebtoken.Jwts;
import org.apache.fineract.cn.anubis.api.v1.TokenConstants;
import org.apache.fineract.cn.anubis.provider.InvalidKeyTimestampException;
import org.apache.fineract.cn.anubis.security.AmitAuthenticationException;
import org.apache.fineract.cn.anubis.token.TenantRefreshTokenSerializer.Specification;
import org.apache.fineract.cn.lang.security.RsaKeyPairFactory;
import org.apache.fineract.cn.test.domain.TimeStampChecker;
import org.junit.Assert;
import org.junit.BeforeClass;
import org.junit.Test;
import org.mockito.Mockito;

import java.time.Duration;
import java.time.LocalDateTime;
import java.time.ZoneOffset;

/**
 * @author Myrle Krantz
 */
public class TenantRefreshTokenSerializerTest {

  private static final String APPLICATION_NAME = "fineract-cn-core";
  private static final int SECONDS_TO_LIVE = 15;
  private static final String USER = "who";
  private static final String ENDPOINT_SET = "what";
  private static RsaKeyPairFactory.KeyPairHolder keyPairHolder;

  @BeforeClass
  public static void initialize()
  {
    keyPairHolder = RsaKeyPairFactory.createKeyPair();
  }

  @Test
  public void shouldCreateValidRefreshToken() throws Exception {
    final Specification specification = getValidSpecification();
    final TenantRefreshTokenSerializer testSubject = new TenantRefreshTokenSerializer();

    final TimeStampChecker timeStampChecker = TimeStampChecker.inTheFuture(Duration.ofSeconds(SECONDS_TO_LIVE));

    final TokenSerializationResult tokenSerializationResult = testSubject.build(specification);

    Assert.assertNotNull(tokenSerializationResult);

    final LocalDateTime expiration = tokenSerializationResult.getExpiration();
    timeStampChecker.assertCorrect(expiration);

    @SuppressWarnings("unchecked") final Jwt<Header, Claims> parsedToken = Jwts
            .parser()
            .setSigningKey(keyPairHolder.publicKey())
            .parse(tokenSerializationResult.getToken().substring("Bearer ".length()).trim());


    Assert.assertNotNull(parsedToken);
    Assert.assertEquals(APPLICATION_NAME, parsedToken.getBody().get("iss"));
    final Integer issued = (Integer) parsedToken.getBody().get("iat");
    Assert.assertNotNull(issued);
    final Integer expires = (Integer) parsedToken.getBody().get("exp");
    Assert.assertNotNull(expires);
    Assert.assertTrue(expires > issued);
    final String signatureTimestamp = parsedToken.getBody().get(TokenConstants.JWT_SIGNATURE_TIMESTAMP_CLAIM, String.class);
    Assert.assertEquals(keyPairHolder.getTimestamp(), signatureTimestamp);
    final String endpointSetClaim = parsedToken.getBody().get(TokenConstants.JWT_ENDPOINT_SET_CLAIM, String.class);
    Assert.assertEquals(null, endpointSetClaim);

    final TokenDeserializationResult tokenDeserializationResult = testSubject.deserialize(getTenantApplicationRsaKeyProvider(), tokenSerializationResult.getToken());
    Assert.assertNotNull(tokenDeserializationResult);
    Assert.assertEquals(APPLICATION_NAME, tokenDeserializationResult.getSourceApplication());
    Assert.assertEquals(USER, tokenDeserializationResult.getUserIdentifier());
    timeStampChecker.assertCorrect(LocalDateTime.ofInstant(tokenDeserializationResult.getExpiration().toInstant(), ZoneOffset.UTC));
    Assert.assertEquals(null, tokenDeserializationResult.getEndpointSet());
  }

  @Test
  public void shouldCreateValidRefreshTokenWithEndpointSet() throws Exception {
    final Specification specification = getValidSpecification();
    specification.setEndpointSet(ENDPOINT_SET);
    final TenantRefreshTokenSerializer testSubject = new TenantRefreshTokenSerializer();

    final TokenSerializationResult tokenSerializationResult = testSubject.build(specification);

    @SuppressWarnings("unchecked") final Jwt<Header, Claims> parsedToken = Jwts
            .parser()
            .setSigningKey(keyPairHolder.publicKey())
            .parse(tokenSerializationResult.getToken().substring("Bearer ".length()).trim());


    final String endpointSetClaim = parsedToken.getBody().get(TokenConstants.JWT_ENDPOINT_SET_CLAIM, String.class);
    Assert.assertEquals(ENDPOINT_SET, endpointSetClaim);

    final TokenDeserializationResult tokenDeserializationResult = testSubject.deserialize(getTenantApplicationRsaKeyProvider(), tokenSerializationResult.getToken());
    Assert.assertEquals(ENDPOINT_SET, tokenDeserializationResult.getEndpointSet());
  }

  @Test(expected = IllegalArgumentException.class)
  public void invalidSecondsToLiveCausesException() throws Exception {
    final Specification specification = getValidSpecification().setSecondsToLive(-1);
    final TenantRefreshTokenSerializer testSubject = new TenantRefreshTokenSerializer();
    testSubject.build(specification);
  }

  @Test(expected = IllegalArgumentException.class)
  public void missingKeyTimestampCausesException() throws Exception {
    final Specification specification = getValidSpecification().setKeyTimestamp(null);
    final TenantRefreshTokenSerializer testSubject = new TenantRefreshTokenSerializer();
    testSubject.build(specification);
  }

  @Test(expected = IllegalArgumentException.class)
  public void missingApplicationCausesException() throws Exception {
    final Specification specification = getValidSpecification().setSourceApplication(null);
    final TenantRefreshTokenSerializer testSubject = new TenantRefreshTokenSerializer();
    testSubject.build(specification);
  }

  @Test(expected = IllegalArgumentException.class)
  public void missingPrivateKeyCausesException() throws Exception {
    final Specification specification = getValidSpecification().setPrivateKey(null);
    final TenantRefreshTokenSerializer testSubject = new TenantRefreshTokenSerializer();
    testSubject.build(specification);
  }

  @Test(expected = AmitAuthenticationException.class)
  public void deserializeNullCausesAmitException() throws Exception {
    final TenantRefreshTokenSerializer testSubject = new TenantRefreshTokenSerializer();
    testSubject.deserialize(getTenantApplicationRsaKeyProvider(), null);
  }

  @Test(expected = AmitAuthenticationException.class)
  public void deserializeUnprefixedTokenCausesAmitException() throws Exception {
    final TenantRefreshTokenSerializer testSubject = new TenantRefreshTokenSerializer();
    testSubject.deserialize(getTenantApplicationRsaKeyProvider(), "randostring");
  }

  @Test(expected = AmitAuthenticationException.class)
  public void tenantHasNotProvidedAPublicKeyDuringDeserializationCausesAmitException() throws Exception {
    final Specification specification = getValidSpecification();
    final TenantApplicationRsaKeyProvider tenantApplicationRsaKeyProvider
            = Mockito.mock(TenantApplicationRsaKeyProvider.class);
    Mockito.when(tenantApplicationRsaKeyProvider.getApplicationPublicKey(APPLICATION_NAME, keyPairHolder.getTimestamp()))
            .thenThrow(new IllegalArgumentException());

    final TenantRefreshTokenSerializer testSubject = new TenantRefreshTokenSerializer();
    final TokenSerializationResult tokenSerializationResult = testSubject.build(specification);
    testSubject.deserialize(tenantApplicationRsaKeyProvider, tokenSerializationResult.getToken());
  }

  @Test(expected = AmitAuthenticationException.class)
  public void tenantHasNotProvidedAPublicKeyForKeyTimestampDuringDeserializationCausesAmitException() throws Exception {
    final Specification specification = getValidSpecification();
    final TenantApplicationRsaKeyProvider tenantApplicationRsaKeyProvider
            = Mockito.mock(TenantApplicationRsaKeyProvider.class);
    Mockito.when(tenantApplicationRsaKeyProvider.getApplicationPublicKey(APPLICATION_NAME, keyPairHolder.getTimestamp()))
            .thenThrow(new InvalidKeyTimestampException(""));

    final TenantRefreshTokenSerializer testSubject = new TenantRefreshTokenSerializer();
    final TokenSerializationResult tokenSerializationResult = testSubject.build(specification);
    testSubject.deserialize(tenantApplicationRsaKeyProvider, tokenSerializationResult.getToken());
  }

  @Test(expected = AmitAuthenticationException.class)
  public void tokenIsSignedWithAWrongKeyCausesAmitException() throws Exception {
    final RsaKeyPairFactory.KeyPairHolder otherKeyPairHolder = RsaKeyPairFactory.createKeyPair();

    final Specification specification = getValidSpecification();
    final TenantApplicationRsaKeyProvider tenantApplicationRsaKeyProvider
            = Mockito.mock(TenantApplicationRsaKeyProvider.class);
    Mockito.when(tenantApplicationRsaKeyProvider.getApplicationPublicKey(APPLICATION_NAME, keyPairHolder.getTimestamp()))
            .thenReturn(otherKeyPairHolder.publicKey());

    final TenantRefreshTokenSerializer testSubject = new TenantRefreshTokenSerializer();
    final TokenSerializationResult tokenSerializationResult = testSubject.build(specification);
    testSubject.deserialize(tenantApplicationRsaKeyProvider, tokenSerializationResult.getToken());
  }

  private Specification getValidSpecification() {
    return new Specification()
            .setUser(USER)
            .setKeyTimestamp(keyPairHolder.getTimestamp())
            .setSourceApplication(APPLICATION_NAME)
            .setPrivateKey(keyPairHolder.privateKey())
            .setSecondsToLive(SECONDS_TO_LIVE);
  }

  private TenantApplicationRsaKeyProvider getTenantApplicationRsaKeyProvider() throws InvalidKeyTimestampException {
    final TenantApplicationRsaKeyProvider tenantRsaKeyProvider = Mockito.mock(TenantApplicationRsaKeyProvider.class);
    Mockito.when(tenantRsaKeyProvider.getApplicationPublicKey(APPLICATION_NAME, keyPairHolder.getTimestamp())).thenReturn(keyPairHolder.publicKey());

    return tenantRsaKeyProvider;
  }
}