/*
    * This file is part of dependency-check-core.
    *
    * 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.
   *
   * Copyright (c) 2012 Jeremy Long. All Rights Reserved.
   */
  package org.owasp.dependencycheck.utils;
  
  import java.io.File;
  import java.io.IOException;
  import java.security.NoSuchAlgorithmException;
  
  import org.junit.Assert;
  import org.junit.Rule;
  import org.junit.Test;
  import org.junit.rules.ExpectedException;
  import org.owasp.dependencycheck.utils.Checksum;
  import org.owasp.dependencycheck.utils.Checksum;
  
  /**
   *
   * @author Jeremy Long <jeremy.long@owasp.org>
   */
  public class ChecksumTest {
  
      @Rule
      public ExpectedException expectedException = ExpectedException.none();
  
      /**
       * Test of getChecksum method, of class Checksum.
       *
       * @throws Exception thrown when an exception occurs.
       */
      @Test
      public void testGetChecksum() throws Exception {
          String algorithm = "MD5";
          File file = new File(this.getClass().getClassLoader().getResource("checkSumTest.file").getPath());
          byte[] expResult = {-16, -111, 92, 95, 70, -72, -49, -94, -125, -27, -83, 103, -96, -101, 55, -109};
          byte[] result = Checksum.getChecksum(algorithm, file);
          boolean arraysAreEqual = true;
          if (expResult.length == result.length) {
              for (int i = 0; arraysAreEqual && i < result.length; i++) {
                  arraysAreEqual = result[i] == expResult[i];
              }
          } else {
              Assert.fail("Checksum results do not match expected results.");
          }
          Assert.assertTrue(arraysAreEqual);
      }
  
      /**
       * Test of getChecksum method, of class Checksum. This checks that an exception is thrown when an invalid path is
       * specified.
       *
       * @throws Exception is thrown when an exception occurs.
       */
      @Test
      public void testGetChecksum_FileNotFound() throws Exception {
          String algorithm = "MD5";
          File file = new File("not a valid file");
  
          expectedException.expect(IOException.class);
          Checksum.getChecksum(algorithm, file);
      }
  
      /**
       * Test of getChecksum method, of class Checksum. This checks that an exception is thrown when an invalid algorithm
       * is specified.
       *
       * @throws Exception is thrown when an exception occurs.
       */
      @Test
      public void testGetChecksum_NoSuchAlgorithm() throws Exception {
          String algorithm = "some unknown algorithm";
          File file = new File(this.getClass().getClassLoader().getResource("checkSumTest.file").getPath());
  
          expectedException.expect(NoSuchAlgorithmException.class);
          Checksum.getChecksum(algorithm, file);
      }
  
      /**
       * Test of getMD5Checksum method, of class Checksum.
       *
       * @throws Exception is thrown when an exception occurs.
       */
      @Test
      public void testGetMD5Checksum() throws Exception {
          File file = new File(this.getClass().getClassLoader().getResource("checkSumTest.file").getPath());
         String expResult = "F0915C5F46B8CFA283E5AD67A09B3793";
         String result = Checksum.getMD5Checksum(file);
         Assert.assertEquals(expResult, result);
     }
 
     /**
      * Test of getSHA1Checksum method, of class Checksum.
      *
      * @throws Exception is thrown when an exception occurs.
      */
     @Test
     public void testGetSHA1Checksum() throws Exception {
         File file = new File(this.getClass().getClassLoader().getResource("checkSumTest.file").getPath());
         String expResult = "B8A9FF28B21BCB1D0B50E24A5243D8B51766851A";
         String result = Checksum.getSHA1Checksum(file);
         Assert.assertEquals(expResult, result);
     }
 
     /**
      * Test of getHex method, of class Checksum.
      */
     @Test
     public void testGetHex() {
         byte[] raw = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16};
         String expResult = "000102030405060708090A0B0C0D0E0F10";
         String result = Checksum.getHex(raw);
         Assert.assertEquals(expResult, result);
     }
 }