madparse

#include <cstdio>
#include <cstring>

int main()
{
    FILE* f = fopen("mars.mad", "rb");
    if (!f) return 1;

    char MadHeader[0x1C];
    if (fread(MadHeader, 0x1C, 1, f) < 1)
        return 2;

    if (strncmp(MadHeader, "WORLD&ART&DIRECTORY", 0x13))
    {
        printf("Not a valid MAD file\n");
        return 3;
    }

    int MadCount = *(int*)(MadHeader+0x14);
    int MadOffset = *(int*)(MadHeader+0x18);

    fseek(f, MadOffset, SEEK_SET);

    char* MadTable = new char[MadCount*16];
    fread(MadTable, 16, MadCount, f);

    char* v10 = MadTable;
    for (int i = 0; i < MadCount*16; i++)
        *v10++ -= 0x30;

    // lets convert this bullshit into a WAD file
    FILE* f2 = fopen("mars.wad", "wb");
    if (!f2) return 4;

    int MadCountReal = MadCount;
    int MadOffsetC = MadOffset;

    for (int i = 0; i < MadCount; i++)
    {
        int LumpOffset = *(int*)(MadTable+i*16);
        int LumpSize = *(int*)(MadTable+i*16+4);
        char LumpName[9];
        LumpName[8] = 0;
        memcpy(LumpName, MadTable+i*16+8, 8);

        if (LumpSize < 0)
            continue;

        if (LumpSize)
        {
            char* lump = new char[LumpSize];
            fseek(f, LumpOffset, SEEK_SET);
            fseek(f2, LumpOffset, SEEK_SET);
            fread(lump, LumpSize, 1, f);
            fwrite(lump, LumpSize, 1, f2);
            delete[] lump;
        }
    }

    for (int i = 0; i < MadCount; i++)
    {
        int LumpOffset = *(int*)(MadTable+i*16);
        int LumpSize = *(int*)(MadTable+i*16+4);
        char LumpName[9];
        LumpName[8] = 0;
        memcpy(LumpName, MadTable+i*16+8, 8);

        if (LumpSize < 0)
        {
            MadCountReal--;
            continue;
        }

        fseek(f2, MadOffsetC, SEEK_SET);
        MadOffsetC += 16;
        fwrite(&LumpOffset, 4, 1, f2);
        fwrite(&LumpSize, 4, 1, f2);
        fwrite(LumpName, 8, 1, f2);
    }

    fseek(f2, 0, SEEK_SET);
    fwrite("PWAD", 4, 1, f2);
    fwrite(&MadCount, 4, 1, f2);
    fwrite(&MadOffset, 4, 1, f2);

    fclose(f2);
    fclose(f);

    return 0;
}