/*
    fasttest.c -
    Copyright (C) Yann Collet 2012-2017

    GPL v2 License

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License along
    with this program; if not, write to the Free Software Foundation, Inc.,
    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.

    You can contact the author at :
    - LZ4 homepage : http://www.lz4.org
    - LZ4 source repo : https://github.com/lz4/lz4
*/

/**************************************
 * Compiler Options
 **************************************/
#ifdef _MSC_VER    /* Visual Studio */
#  define _CRT_SECURE_NO_WARNINGS  /* for MSVC */
#  define snprintf sprintf_s
#endif
#ifdef __GNUC__
#  pragma GCC diagnostic ignored "-Wmissing-braces"   /* GCC bug 53119 : doesn't accept { 0 } as initializer (https://gcc.gnu.org/bugzilla/show_bug.cgi?id=53119) */
#endif


/**************************************
 * Includes
 **************************************/
#include <stdio.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include "lz4.h"


/* Returns non-zero on failure. */
int test_compress(const char *input, int inSize, char *output, int outSize)
{
    LZ4_stream_t lz4Stream_body = { 0 };
    LZ4_stream_t* lz4Stream = &lz4Stream_body;

    int inOffset = 0;
    int outOffset = 0;

    if (inSize & 3) return -1;

    while (inOffset < inSize) {
        const int length = inSize >> 2;
        if (inSize > 1024) return -2;
        if (outSize - (outOffset + 8) < LZ4_compressBound(length)) return -3;
        {   const int outBytes = LZ4_compress_fast_continue(
                lz4Stream, input + inOffset, output + outOffset + 8,
                length, outSize-outOffset, 1);
            if(outBytes <= 0) return -4;
            memcpy(output + outOffset, &length, 4); /* input length */
            memcpy(output + outOffset + 4, &outBytes, 4); /* output length */
            inOffset += length;
            outOffset += outBytes + 8;
    }   }
    if (outOffset + 8 > outSize) return -5;
    memset(output + outOffset, 0, 4);
    memset(output + outOffset + 4, 0, 4);
    return 0;
}

/* Returns non-zero on failure. Not a safe function. */
int test_decompress(const char *uncompressed, const char *compressed)
{
    char outBufferA[1024];
    char spacing; /* So prefixEnd != dest */
    char outBufferB[1024];
    char *output = outBufferA;
    char *lastOutput = outBufferB;
    LZ4_streamDecode_t lz4StreamDecode_body = { 0 };
    LZ4_streamDecode_t* lz4StreamDecode = &lz4StreamDecode_body;
    int offset = 0;
    int unOffset = 0;
    int lastBytes = 0;

    (void)spacing;

    for(;;) {
        int32_t bytes;
        int32_t unBytes;
        /* Read uncompressed size and compressed size */
        memcpy(&unBytes, compressed + offset, 4);
        memcpy(&bytes, compressed + offset + 4, 4);
        offset += 8;
        /* Check if we reached end of stream or error */
        if(bytes == 0 && unBytes == 0) return 0;
        if(bytes <= 0 || unBytes <= 0 || unBytes > 1024) return 1;

        /* Put the last output in the dictionary */
        LZ4_setStreamDecode(lz4StreamDecode, lastOutput, lastBytes);
        /* Decompress */
        bytes = LZ4_decompress_fast_continue(
            lz4StreamDecode, compressed + offset, output, unBytes);
        if(bytes <= 0) return 2;
        /* Check result */
        {   int const r = memcmp(uncompressed + unOffset, output, unBytes);
            if (r) return 3;
        }
        { char* const tmp = output; output = lastOutput; lastOutput = tmp; }
        offset += bytes;
        unOffset += unBytes;
        lastBytes = unBytes;
    }
}


int main(int argc, char **argv)
{
    char input[] =
        "Hello Hello Hello Hello Hello Hello Hello Hello!"
        "Hello Hello Hello Hello Hello Hello Hello Hello!"
        "Hello Hello Hello Hello Hello Hello Hello Hello!"
        "Hello Hello Hello Hello Hello Hello Hello Hello!"
        "Hello Hello Hello Hello Hello Hello Hello Hello!"
        "Hello Hello Hello Hello Hello Hello Hello Hello!"
        "Hello Hello Hello Hello Hello Hello Hello Hello!"
        "Hello Hello Hello Hello Hello Hello Hello Hello!"
        "Hello Hello Hello Hello Hello Hello Hello Hello!"
        "Hello Hello Hello Hello Hello Hello Hello Hello!"
        "Hello Hello Hello Hello Hello Hello Hello Hello!"
        "Hello Hello Hello Hello Hello Hello Hello Hello!"
        "Hello Hello Hello Hello Hello Hello Hello Hello!"
        "Hello Hello Hello Hello Hello Hello Hello Hello!"
        "Hello Hello Hello Hello Hello Hello Hello Hello!"
        "Hello Hello Hello Hello Hello Hello Hello Hello";
    char output[LZ4_COMPRESSBOUND(4096)];
    int r;

    (void)argc;
    (void)argv;

    if ((r = test_compress(input, sizeof(input), output, sizeof(output)))) {
        return r;
    }
    if ((r = test_decompress(input, output))) {
        return r;
    }
    return 0;
}