#include <Windows.h>
#include <cli-parser.hpp>
#include <devirt_t.hpp>
#include <xtils.hpp>

/// <summary>
/// helper function to serialize vmp2 file data to vm::instr::code_block's...
/// </summary>
/// <param name="virt_rtns">vector of pairs {vm enter offset, vector of code blocks} which gets filled up with
/// serialized data</param>
/// <param name="vmp2file">a vector of bytes containing the vmp2 file...</param>
/// <returns>returns true if serialization was successful</returns>
bool serialize_vmp2( std::vector< std::pair< std::uint32_t, std::vector< vm::instrs::code_block_t > > > &virt_rtns,
                     std::vector< std::uint8_t > &vmp2file )
{
    const auto file_header = reinterpret_cast< vmp2::v4::file_header * >( vmp2file.data() );

    if ( file_header->version != vmp2::version_t::v4 )
    {
        std::printf( "[!] invalid vmp2 file version... this build uses v3...\n" );
        return false;
    }

    auto first_rtn = reinterpret_cast< vmp2::v4::rtn_t * >( reinterpret_cast< std::uintptr_t >( file_header ) +
                                                            file_header->rtn_offset );

    for ( auto [ rtn_block, rtn_idx ] = std::pair{ first_rtn, 0ull }; rtn_idx < file_header->rtn_count;
          ++rtn_idx, rtn_block = reinterpret_cast< vmp2::v4::rtn_t * >(
                         reinterpret_cast< std::uintptr_t >( rtn_block ) + rtn_block->size ) )
    {
        virt_rtns.push_back( { rtn_block->vm_enter_offset, {} } );
        for ( auto [ code_block, block_idx ] = std::pair{ &rtn_block->code_blocks[ 0 ], 0ull };
              block_idx < rtn_block->code_block_count;
              ++block_idx, code_block = reinterpret_cast< vmp2::v4::code_block_t * >(
                               reinterpret_cast< std::uintptr_t >( code_block ) + code_block->next_block_offset ) )
        {
            auto block_vinstrs = reinterpret_cast< vm::instrs::virt_instr_t * >(
                reinterpret_cast< std::uintptr_t >( code_block ) + sizeof vmp2::v4::code_block_t +
                ( code_block->num_block_addrs * 8 ) );

            vm::instrs::code_block_t _code_block{ code_block->vip_begin };
            _code_block.jcc.has_jcc = code_block->has_jcc;
            _code_block.jcc.type = code_block->jcc_type;

            for ( auto idx = 0u; idx < code_block->num_block_addrs; ++idx )
                _code_block.jcc.block_addr.push_back( code_block->branch_addr[ idx ] );

            for ( auto idx = 0u; idx < code_block->vinstr_count; ++idx )
                _code_block.vinstrs.push_back( block_vinstrs[ idx ] );

            virt_rtns.back().second.push_back( _code_block );
        }
    }

    return true;
}

int main( int argc, const char *argv[] )
{
    argparse::argument_parser_t parser( "vmdevirt", "virtual instruction pseudo code generator" );
    parser.add_argument().name( "--vmp2file" ).required( true ).description( "path to .vmp2 file..." );

    parser.enable_help();
    auto err = parser.parse( argc, argv );

    if ( err )
    {
        std::cout << err << std::endl;
        return -1;
    }

    if ( parser.exists( "help" ) )
    {
        parser.print_help();
        return 0;
    }

    std::vector< std::uint8_t > vmp2file;
    const auto umtils = xtils::um_t::get_instance();

    if ( !umtils->open_binary_file( parser.get< std::string >( "vmp2file" ), vmp2file ) )
    {
        std::printf( "[!] failed to open vmp2 file...\n" );
        return -1;
    }

    const auto file_header = reinterpret_cast< vmp2::v4::file_header * >( vmp2file.data() );
    std::vector< std::pair< std::uint32_t, std::vector< vm::instrs::code_block_t > > > virt_rtns;

    if ( !serialize_vmp2( virt_rtns, vmp2file ) )
    {
        std::printf( "> failed to serialize vmp2 file...\n" );
        return false;
    }

    llvm::LLVMContext llvm_ctx;
    llvm::Module llvm_module( "VMProtect 2 Devirtualization", llvm_ctx );

    std::vector< std::uint8_t > compiled_obj;
    vm::devirt_t vmp_rtn( &llvm_ctx, &llvm_module );

    for ( auto &[ vm_enter_offset, vmp2_code_blocks ] : virt_rtns )
    {
        if ( !vmp_rtn.lift( vm_enter_offset + file_header->image_base, vmp2_code_blocks ) )
        {
            std::printf( "[!] failed to lift rtn_0x%p, please review the console...\n",
                         vm_enter_offset + file_header->image_base );
            return -1;
        }
    }

    vmp_rtn.compile( compiled_obj );
    std::printf( "> compiled obj size = %d\n", compiled_obj.size() );
}