/*
    * 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.log4j.util;
  
  import java.io.BufferedReader;
  import java.io.File;
  import java.io.FileInputStream;
  import java.io.FileNotFoundException;
  import java.io.FileReader;
  import java.io.IOException;
  import java.io.InputStream;
  import java.io.InputStreamReader;
  import java.util.zip.GZIPInputStream;
  
  
  public class Compare {
    static final int B1_NULL = -1;
    static final int B2_NULL = -2;
  
    private static final InputStream open(
            final Class testClass,
            final String fileName) throws IOException {
        String resourceName = fileName;
        if (fileName.startsWith("witness/")) {
            resourceName = fileName.substring(fileName.lastIndexOf('/') + 1);
        }
        InputStream is = testClass.getResourceAsStream(resourceName);
        if (is == null) {
            File file = new File(fileName);
            if (file.exists()) {
                is = new FileInputStream(file);
            } else {
                throw new FileNotFoundException("Resource "
                        + resourceName + " not found");
            }
        }
        return is;
    }
  
    public static boolean compare(Class testClass,
                                  final String file1,
                                  final String file2)
      throws IOException {
      BufferedReader in1 = new BufferedReader(new FileReader(file1));
      BufferedReader in2 = new BufferedReader(new InputStreamReader(
              open(testClass, file2)));
      try {
        return compare(testClass, file1, file2, in1, in2);
      } finally {
        in1.close();
        in2.close();
      }
    }
      
   public static boolean compare(
           Class testClass, String file1, String file2, BufferedReader in1, BufferedReader in2) throws IOException {
  
      String s1;
      int lineCounter = 0;
  
      while ((s1 = in1.readLine()) != null) {
        lineCounter++;
  
        String s2 = in2.readLine();
  
        if (!s1.equals(s2)) {
          System.out.println(
            "Files [" + file1 + "] and [" + file2 + "] differ on line "
            + lineCounter);
          System.out.println("One reads:  [" + s1 + "].");
          System.out.println("Other reads:[" + s2 + "].");
          outputFile(testClass, file1);
          outputFile(testClass, file2);
  
          return false;
        }
      }
  
      // the second file is longer
      if (in2.read() != -1) {
        System.out.println(
          "File [" + file2 + "] longer than file [" + file1 + "].");
        outputFile(testClass, file1);
        outputFile(testClass, file2);
 
       return false;
     }
 
     return true;
   }
 
   /** 
    * 
    * Prints file on the console.
    *
    */
   private static void outputFile(Class testClass, String file)
     throws IOException {
     InputStream is = open(testClass, file);
     BufferedReader in1 = new BufferedReader(new InputStreamReader(is));
 
     String s1;
     int lineCounter = 0;
     System.out.println("--------------------------------");
     System.out.println("Contents of " + file + ":");
 
     while ((s1 = in1.readLine()) != null) {
       lineCounter++;
       System.out.print(lineCounter);
 
       if (lineCounter < 10) {
         System.out.print("   : ");
       } else if (lineCounter < 100) {
         System.out.print("  : ");
       } else if (lineCounter < 1000) {
         System.out.print(" : ");
       } else {
         System.out.print(": ");
       }
 
       System.out.println(s1);
     }
     in1.close();
   }
 
 
     public static boolean gzCompare(final Class testClass,
                                     final String actual,
                                     final String expected)
       throws FileNotFoundException, IOException {
       String resourceName = expected;
       int lastSlash = expected.lastIndexOf("/");
       if (lastSlash >= 0) {
           resourceName = expected.substring(lastSlash + 1);
       }
       InputStream resourceStream = testClass.getResourceAsStream(resourceName);
       if (resourceStream == null) {
           throw new FileNotFoundException("Could not locate resource " + resourceName);
       }
 
       BufferedReader in1 = new BufferedReader(new InputStreamReader(new GZIPInputStream(new FileInputStream(actual))));
       BufferedReader in2 = new BufferedReader(new InputStreamReader(new GZIPInputStream(resourceStream)));
       try {
         return gzCompare(testClass, actual, expected, in1, in2);
       } finally {
         in1.close();
         in2.close();
       }
     }
 
     public static boolean gzCompare(Class testClass, String file1, String file2, BufferedReader in1, BufferedReader in2) throws IOException {
 
       String s1;
       int lineCounter = 0;
 
       while ((s1 = in1.readLine()) != null) {
         lineCounter++;
 
         String s2 = in2.readLine();
 
         if (!s1.equals(s2)) {
           System.out.println(
             "Files [" + file1 + "] and [" + file2 + "] differ on line "
             + lineCounter);
           System.out.println("One reads:  [" + s1 + "].");
           System.out.println("Other reads:[" + s2 + "].");
           outputFile(testClass, file1);
           outputFile(testClass, file2);
 
           return false;
         }
       }
 
       // the second file is longer
       if (in2.read() != -1) {
         System.out.println(
           "File [" + file2 + "] longer than file [" + file1 + "].");
         outputFile(testClass, file1);
         outputFile(testClass, file2);
 
         return false;
       }
 
       return true;
     }
 
 }