/*
 * EX18CON.C
 *
 *  C/DOS Example program for ArchiveLib 2.0
 *
 *  Copyright (c) Greenleaf Software, Inc. 1994 - 1996
 *  All Rights Reserved
 *
 * MEMBERS/FUNCTIONS DEMONSTRATED
 *
 *  newALCompressedObject()
 *  deleteALCompressed()
 *  ALCompressedExtract()
 *  ALCompressedInsert()
 *  ALCompressedGetStatusCode()
 *  ALCompressedGetStatusDetail()
 *  ALCompressedGetStatusString()
 *  ALCompressedSetError()
 *  ALStoragePackedAttributes()
 *  ALStorageSetFromDosAttributes()
 *  ALStorageSetFromPackedAtts()
 *  ALStorageSetTimeDateFromUnix()
 *
 * DESCRIPTION
 *
 *  This is another one of those example programs that ties together
 *  a bunch of marginally related functions.  It starts off by creating
 *  a data file on disk, and writing some fixed patterns out to it.  Next,
 *  the data file gets inserted into a compressed object, also on disk.
 *  Then the weird part:  If a random number hits, I randomly change a
 *  byte in the compressed object.  Finally, I extract the original data
 *  file from the compressed object, for better or worse.
 *
 *  After this is all done, I have three TMP files on the disk.  In an
 *  imitation of what you might do in a real debugging situation, I check
 *  to see if the input and output match.  If they do match, I just go
 *  ahead and delete them, all is well.  If they don't match, I want to
 *  hang on to the files.  Not only do I hang on to the files, I give
 *  them a funny time date stamp, and set them to be read-only.
 *
 * REVISION HISTORY
 *
 *  February 1, 1996  2.0A  : Second release
 *
 */

#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <conio.h>

#include "al.h"

int main()
{
    hALStorage DataFile;
    hALStorage CompressedFile;
    hALStorage OutputFile;
    hALCompressor Compressor;
    hALDecompressor Decompressor;
    hALCompressed CompressedObject;
    int status;
    short unsigned int atts;
    int i;
    int j;

    printf( "Archive Library 2.0\nEX18CON.C\n\n" );
    printf( "This is another one of those example programs that ties together\n" );
    printf( "a bunch of marginally related functions.  It starts off by creating\n" );
    printf( "a data file on disk, and writing some fixed patterns out to it.  Next,\n" );
    printf( "the data file gets inserted into a compressed object, also on disk.\n" );
    printf( "Then the weird part:  If a random number hits, I randomly change a\n" );
    printf( "byte in the compressed object.  Finally, I extract the original data\n" );
    printf( "file from the compressed object, for better or worse.\n\n" );
    getch();

#if defined( ZIP )
    Compressor = newALPkCompressor( AL_DEFAULT, AL_DEFAULT, AL_DEFAULT );
    Decompressor = newALPkDecompressor();
#else
    Compressor = newALGlCompressor( AL_DEFAULT, 0 );
    Decompressor = newALGlDecompressor( AL_DEFAULT );
#endif
/*
 * Here is where I create the input data file and the compressed object.
 * This is all fairly realistic, you could write code that looks a lot
 * like this.
 */
    DataFile = newALFile( "" );
    CompressedFile = newALFile( "" );
    OutputFile = newALFile( "" );
    CompressedObject = newALCompressed( CompressedFile, Compressor, Decompressor );
    ALStorageCreate( DataFile, -1 ); /* Temporary file */
    for ( i = 0 ; i < 64 ; i++ )
        for ( j = i; j < 64 ; j++ )
            ALStorageWriteChar( DataFile, j );
    ALStorageClose( DataFile );
    ALCompressedInsert( CompressedObject, DataFile );
/*
 * If the one in four chance hits, I change a single byte in the compressed
 * file.  This will almost always cause an expansion error, although it
 * is possible to create a benign change (like the 1/256 chance that you
 * write over the old byte with a new byte that is the same!)
 */
    srand( (unsigned) time( NULL ) );
    if ( ( rand() & 3 ) == 0 ) {
        printf( "Mangling the compressed file!\n" );
        ALStorageOpen( CompressedFile );
        ALStorageSeek( CompressedFile, 32 + ( rand() & 31 ));
        ALStorageWriteChar( CompressedFile, ( rand() & 0xff ) );
        ALStorageClose( CompressedFile );
    }
/*
 * Now I try to extract the output file.  Once I have done that, I perform
 * a compare to the original to see how things went.  Note that there is
 * a tricky bit here.  The only time ALFile objects will get new time/date
 * and attribute stamps is if they are closed immediately after having been
 * created.  The CompressedObject->Extract() call will create the file,
 * then close it.  Once it is closed, the flag indicating that it was just
 * created will be cleared, so I won't be able to set the time stamp.  But,
 * if *I* create it here, the Extract() function will leave it open after
 * performing its magic.  After it returns, I have to close the file,
 * but I can mung the time/date stamp first.
 */
    ALStorageCreate( OutputFile, AL_DEFAULT );
    ALCompressedExtract( CompressedObject, OutputFile );
    ALStorageSeek( OutputFile, 0L );
    status = ALStorageCompare( DataFile, OutputFile );
    printf( "Compare returned : %d\n", status );
/*
 * If the comparison passed, I just delete all of the TMP files created
 * here.  (Note that they all have TMP names because I didn't give them
 * any names in their constructors.)
 */
    if ( status >= 0 ) {
        ALStorageDelete( DataFile );
        ALStorageDelete( CompressedFile );
        ALStorageClose( OutputFile );
        ALStorageDelete( OutputFile );
    } else {
        ALStorageSetTimeDateFromUnix(
              OutputFile,
              20L*365L*24L*60L*60L + 5L*24L*60L*60L + 12L*60L*60L );
        atts = ALStoragePackedAttributes( OutputFile );
        atts = (short unsigned int) ( atts | ATTR_READ_ONLY );
        ALStorageSetFromPackedAtts( OutputFile, atts );
        ALStorageClose( OutputFile );
        ALCompressedSetError( CompressedObject,
                              status,
                              ALStorageGetStatusDetail( DataFile ) );
    }
    printf( "Compressed object status code:    %d\n",
            ALCompressedGetStatusCode( CompressedObject ) );
    printf( "Compressed object status string:  %s\n",
            ALCompressedGetStatusString( CompressedObject ) );
    printf( "Compressed object status detail:  %s\n",
            ALCompressedGetStatusDetail( CompressedObject ) );

    deleteALCompressed( CompressedObject );
    deleteALCompressor( Compressor );
    deleteALDecompressor( Decompressor );
    deleteALStorage( CompressedFile );
    deleteALStorage( DataFile );
    deleteALStorage( OutputFile );
    return status;
}