package org.apache.maven.scm.provider.cvslib.command.login;

/*
 * Copyright 2001-2005 The Apache Software Foundation.
 *
 * 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.
 */

import org.apache.maven.scm.ScmException;
import org.apache.maven.scm.log.ScmLogger;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.io.PrintWriter;

/**
 * Adds an new entry to a CVS password file.
 *
 * @version $Id$
 * @todo Update this class for support password storage in cvsnt. CVSNT use the windows registry, so, we need a jni
 * tool for access to the windows registry
 */
public class CvsPass
{
    /** CVS Root */
    private String cvsRoot = null;

    /** Password file to add password to */
    private File passFile = null;

    /** Password to add to file */
    private String password = null;
    
    private ScmLogger logger;

    /** Array contain char conversion data */
    private final char[] shifts = {
        0,   1,   2,   3,   4,   5,   6,   7,   8,   9,  10,  11,  12,  13,  14,  15,
       16,  17,  18,  19,  20,  21,  22,  23,  24,  25,  26,  27,  28,  29,  30,  31,
      114, 120,  53,  79,  96, 109,  72, 108,  70,  64,  76,  67, 116,  74,  68,  87,
      111,  52,  75, 119,  49,  34,  82,  81,  95,  65, 112,  86, 118, 110, 122, 105,
       41,  57,  83,  43,  46, 102,  40,  89,  38, 103,  45,  50,  42, 123,  91,  35,
      125,  55,  54,  66, 124, 126,  59,  47,  92,  71, 115,  78,  88, 107, 106,  56,
       36, 121, 117, 104, 101, 100,  69,  73,  99,  63,  94,  93,  39,  37,  61,  48,
       58, 113,  32,  90,  44,  98,  60,  51,  33,  97,  62,  77,  84,  80,  85, 223,
      225, 216, 187, 166, 229, 189, 222, 188, 141, 249, 148, 200, 184, 136, 248, 190,
      199, 170, 181, 204, 138, 232, 218, 183, 255, 234, 220, 247, 213, 203, 226, 193,
      174, 172, 228, 252, 217, 201, 131, 230, 197, 211, 145, 238, 161, 179, 160, 212,
      207, 221, 254, 173, 202, 146, 224, 151, 140, 196, 205, 130, 135, 133, 143, 246,
      192, 159, 244, 239, 185, 168, 215, 144, 139, 165, 180, 157, 147, 186, 214, 176,
      227, 231, 219, 169, 175, 156, 206, 198, 129, 164, 150, 210, 154, 177, 134, 127,
      182, 128, 158, 208, 162, 132, 167, 209, 149, 241, 153, 251, 237, 236, 171, 195,
      243, 233, 253, 240, 194, 250, 191, 155, 142, 137, 245, 235, 163, 242, 178, 152
    };

    /**
     * Create a CVS task using the default cvspass file location.
     */
    public CvsPass( ScmLogger logger )
    {
        passFile = new File( System.getProperty( "cygwin.user.home", System.getProperty( "user.home" ) )
                             + File.separatorChar + ".cvspass" );
        this.logger = logger;
    }

    /**
     * Does the work.
     *
     * @exception ScmException if something is missing
     * @exception IOException if something goes wrong
     */
    public final void execute()
        throws ScmException, IOException
    {
        if ( cvsRoot == null )
        {
            throw new ScmException( "cvsroot is required" );
        }

        logger.debug( "cvsRoot: " + cvsRoot );

        logger.debug( "passFile: " + passFile );

        BufferedReader reader = null;

        PrintWriter writer = null;
        try
        {
            StringBuffer buf = new StringBuffer();

            if ( passFile.exists() )
            {
                reader = new BufferedReader( new FileReader( passFile ) );

                String line = null;

                while ( ( line = reader.readLine() ) != null )
                {
                    if ( !line.startsWith( cvsRoot ) && !line.startsWith( "/1 " + cvsRoot ) )
                    {
                        buf.append( line ).append( "\n" );
                    }
                    else
                    {
                        logger.debug( "cvsroot " + cvsRoot + " already exist in " + passFile.getAbsolutePath() + ". SKIPPED." );

                        return;
                    }
                }
            }

            if ( password == null )
            {
                throw new ScmException( "password is required" );
            }

            //logger.debug( "password: " + password );

            String pwdfile = buf.toString() + "/1 " + cvsRoot + " A" + mangle( password );

            logger.debug( "Writing -> " + pwdfile );

            writer = new PrintWriter( new FileWriter( passFile ) );

            writer.println( pwdfile );
        }
        finally
        {
            if ( reader != null )
            {
                try
                {
                    reader.close();
                }
                catch ( IOException e )
                {
                    // ignore
                }
            }
            if ( writer != null )
            {
                writer.close();
            }
        }
    }

    private final String mangle( String password )
    {
        StringBuffer buf = new StringBuffer();
        for ( int i = 0; i < password.length(); i++ )
        {
            buf.append( shifts[password.charAt( i )] );
        }
        return buf.toString();
    }

    /**
     * The CVS repository to add an entry for.
     *
     * @param cvsRoot the CVS repository
     */
    public void setCvsroot( String cvsRoot )
    {
        this.cvsRoot = cvsRoot;
    }

    /**
     * Password file to add the entry to.
     *
     * @param passFile the password file.
     */
    public void setPassfile( File passFile )
    {
        this.passFile = passFile;
    }

    /**
     * Password to be added to the password file.
     *
     * @param password the password.
     */
    public void setPassword( String password )
    {
        this.password = password;
    }

}