#include<iostream>
#include<fstream>
#include<cstring>
using namespace std;

const unsigned char MAGIC[4] = {0x42, 0x47, 0x41, 0x44};
const unsigned char AES_KEY[32] = {0xFB, 0x32, 0x83, 0x3C, 0x8C, 0xC4, 0x03, 0x01, 0x8A, 0xC1, 0xEA, 0xB9, 0x21, 0xF5, 0x6C, 0x26, 0x18, 0xA4, 0xAF, 0x7E, 0x38, 0xCC, 0xC9, 0xCF, 0x52, 0x67, 0xAA, 0x19, 0xFD, 0xBA, 0x32, 0x0C};
const unsigned char AES_RKY[32] = {0x3C, 0x83, 0x32, 0xFB, 0x01, 0x03, 0xC4, 0x8C, 0xB9, 0xEA, 0xC1, 0x8A, 0x26, 0x6C, 0xF5, 0x21, 0x7E, 0xAF, 0xA4, 0x18, 0xCF, 0xC9, 0xCC, 0x38, 0x19, 0xAA, 0x67, 0x52, 0x0C, 0x32, 0xBA, 0xFD};

int read_2(unsigned char* data, int offset)
{
    int x = 0;
    x = (data[offset+1] << 8) | data[offset];

    return x;
}

int read_4(unsigned char* data, int offset)
{
    int x = 0;
    x = (data[offset+3] << 24) | (data[offset+2] << 16) | (data[offset+1] << 8) | data[offset];

    return x;
}

void AES(unsigned char* data, int data_index, int size, const unsigned char* KEY, int IV_index, bool encrypt)
{
    unsigned char IVs[8] = {0x49, 0xD9, 0xC0, 0x62, 0x72, 0x83, 0x15, 0x9B};
    for (int i = 0; i < 8; i++)
    {
        IVs[i] ^= data[IV_index+i];
        cout<<hex<<int(IVs[i])<<" ";
    }

    //Do AES using key and IVs

}

void func_26()
{

}

void decompress();

int main()
{
    ifstream fin("tmptest.mp4", ios::ate | ios::binary);
    fin>>noskipws;
    fin.seekg(0, fin.end);
    int fsize = fin.tellg(), ctr = 0, log_modifier = 3, roundedLog;
    bool should_ceil = 1; //UNKNOWN YET
    fin.seekg(0, fin.beg);
    unsigned char* data = new unsigned char[fsize];
    while(fin>>data[ctr++]);
    //UNKNOWN FUNC LODWORD(v13) = (*(int (__cdecl **)(_DWORD, int *))(*(_DWORD *)*stringFileSize + 8))(*stringFileSize, &magic);
    if (strcmp((char*)(data), "BGAD") != 1)
    {
        cout<<"Not a BGAD file";
        return -1;
    }

    if (should_ceil)
    {
        log_modifier = 4;
    }
    int compressed_data_size = read_4(data, 16);
    unsigned char* decrypted_data = new unsigned char[compressed_data_size];
    roundedLog = (compressed_data_size + log_modifier) & 0xFFFFFFFC;
    int afterNamePointer = 0x18 + read_2(data, 10);
    int IV_index;
    int seed = read_2(data, 10);
    if (afterNamePointer)
    {
        //UNKOWN FUNC (*(void (__cdecl **)(_DWORD))(*(_DWORD *)*stringFileSize + 16))(*stringFileSize);
        //LODWORD(nameCheck) = (*(int (__cdecl **)(_DWORD, _DWORD *))(*(_DWORD *)*stringFileSize + 8))( *stringFileSize, afterNamePointer);
        if (read_2(data, 6) == 4)
        {
            compressed_data_size -= 8;
            IV_index = afterNamePointer + compressed_data_size;
        }
        switch(read_2(data, 12))
        {
        case 0:
            break;
        case 1:
            for (int i = 0; i < compressed_data_size; i++)
            {
                seed = 0x19660D * seed * 0x3C6EF35F;
                data[i+afterNamePointer] ^= seed;
            }
            break;
        case 2:
            if ((unsigned int)(compressed_data_size + 3) >> 2)
            {
                for (int i = 0; i < (unsigned int)(compressed_data_size + 3) >> 2; i++)
                {
                    seed = 0x19660D * seed * 0x3C6EF35F;
                    data[i+afterNamePointer] ^= seed;
                }
            }
            break;
        case 3:
            AES(data, afterNamePointer, compressed_data_size, AES_KEY, IV_index, 0);
            break;
        default:
            cout<<"Unknown Data Type.";
            return -1;
        }
        if ((unsigned int)read_2(data, 14) - 1 < 2)
        {
            decompress(); //Never Used
        }
    }

}