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 * 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   *
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 *   http://www.apache.org/licenses/LICENSE-2.0                 *
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 * 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.                                           *
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package org.apache.james.mime4j.io;

import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.UnsupportedEncodingException;

import org.apache.james.mime4j.io.EOLConvertingInputStream;


import junit.framework.TestCase;

public class EOLConvertingInputStreamTest extends TestCase {

    public void testRead() throws IOException {
        testConvertBoth("Line 1\r\nLine 2\r\n", "Line 1\r\nLine 2\r\n");
        testConvertCR("Line 1\r\nLine 2\r\n", "Line 1\r\nLine 2\r\n");
        testConvertLF("Line 1\r\nLine 2\r\n", "Line 1\r\nLine 2\r\n");
        
        testConvertBoth("Line 1\n\rLine 2\n\r", "Line 1\r\n\r\nLine 2\r\n\r\n");
        testConvertCR("Line 1\n\rLine 2\n\r", "Line 1\n\r\nLine 2\n\r\n");
        testConvertLF("Line 1\n\rLine 2\n\r", "Line 1\r\n\rLine 2\r\n\r");
        
        testConvertBoth("Line 1\nLine 2\n", "Line 1\r\nLine 2\r\n");
        testConvertCR("Line 1\nLine 2\n", "Line 1\nLine 2\n");
        testConvertLF("Line 1\nLine 2\n", "Line 1\r\nLine 2\r\n");
        
        testConvertBoth("Line 1\rLine 2\r", "Line 1\r\nLine 2\r\n");
        testConvertCR("Line 1\rLine 2\r", "Line 1\r\nLine 2\r\n");
        testConvertLF("Line 1\rLine 2\r", "Line 1\rLine 2\r");
        
        testConvertBoth("\r\n", "\r\n");
        testConvertCR("\r\n", "\r\n");
        testConvertLF("\r\n", "\r\n");
        
        testConvertBoth("\n", "\r\n");
        testConvertCR("\n", "\n");
        testConvertLF("\n", "\r\n");
        
        testConvertBoth("\r", "\r\n");
        testConvertCR("\r", "\r\n");
        testConvertLF("\r", "\r");
        
        testConvertBoth("", "");
        testConvertCR("", "");
        testConvertLF("", "");
    }

    private void testConvertBoth(String s1, String s2) throws IOException {
        byte[] bytes = new byte[1024];
        
        ByteArrayInputStream bais = new ByteArrayInputStream(fromString(s1));
        EOLConvertingInputStream in = 
            new EOLConvertingInputStream(bais, 
                        EOLConvertingInputStream.CONVERT_BOTH);
        int n = in.read(bytes);
        assertEquals(s2, toString(bytes, n));
    }
    
    private void testConvertCR(String s1, String s2) throws IOException {
        byte[] bytes = new byte[1024];
        
        ByteArrayInputStream bais = new ByteArrayInputStream(fromString(s1));
        EOLConvertingInputStream in = 
            new EOLConvertingInputStream(bais, 
                        EOLConvertingInputStream.CONVERT_CR);
        int n = in.read(bytes);
        assertEquals(s2, toString(bytes, n));
    }
    
    private void testConvertLF(String s1, String s2) throws IOException {
        byte[] bytes = new byte[1024];
        
        ByteArrayInputStream bais = new ByteArrayInputStream(fromString(s1));
        EOLConvertingInputStream in = 
            new EOLConvertingInputStream(bais, 
                        EOLConvertingInputStream.CONVERT_LF);
        int n = in.read(bytes);
        assertEquals(s2, toString(bytes, n));
    }
    
    private String toString(byte[] b, int len) {
        try {
            if (len == -1) {
                return "";
            }
            return new String(b, 0, len, "US-ASCII");
        } catch (UnsupportedEncodingException e) {
            fail(e.getMessage());
            return null;
        }
    }    
    
    private byte[] fromString(String s) {
        try {
            return s.getBytes("US-ASCII");
        } catch (UnsupportedEncodingException e) {
            fail(e.getMessage());
            return null;
        }
    }    
}