PowerShell and Python utility to cut data file out of combined TyranoBuilder executable

tyranocut.cmd

powershell -executionPolicy bypass -file "tyranocut.ps1" -Unpack -GameExeName %1

tyranocut.ps1

# PowerShell utility to cut data file out of combined TyranoBuilder executable
# Run as:
#    powershell -executionPolicy bypass -file "tyranocut.ps1" -GameExeName "game.exe"
#    powershell -executionPolicy bypass -file "tyranocut.ps1" -Unpack -GameExeName "game.exe"
#

Param(
[parameter(Mandatory=$true, HelpMessage="Provide file name of game exe")][string]$GameExeName,
[switch]$Unpack = $false
)

Set-StrictMode -Version Latest
$ErrorActionPreference = "Stop"
$PSDefaultParameterValues['*:ErrorAction']='Stop'

function ConvertTo-BinaryString {
    # Converts the bytes of a file to a string that has a 1-to-1 mapping back to the file's original bytes. 
    # Useful for performing binary regular expressions.
    [OutputType([String])]
    Param (
        [Parameter(Mandatory = $True, ValueFromPipeline = $True, Position = 0)]
        [ValidateScript( { Test-Path $_ -PathType Leaf } )]
        [String]$Path
    )

    $Stream = New-Object System.IO.FileStream -ArgumentList $Path, 'Open', 'Read'
    $Encoding     = [Text.Encoding]::GetEncoding(28591)
    $StreamReader = New-Object System.IO.StreamReader -ArgumentList $Stream, $Encoding
    $BinaryText   = $StreamReader.ReadToEnd()

    $StreamReader.Close()
    $Stream.Close()

    return $BinaryText
}

if (-Not (Test-Path -LiteralPath $GameExeName)) { 
    Write-Host "$GameExeName file not found or path contains brackets."
    exit
}

$outputFile = $GameExeName
$inputFile  = [System.IO.Path]::GetFileNameWithoutExtension($GameExeName) + '.old'
$outputData = 'data.zip'
# Signature of first merged .nw file inside .exe file
$re = [Regex]'\x50\x4B\x03\x04\x0A\x00\x00\x00\x00\x00'

Write-Host "Processing $outputFile..."
if (Test-Path -LiteralPath $inputFile) { 
    Write-Host "Backup of game exe already exists."
    exit
}

Rename-Item -Path $outputFile -NewName $inputFile
$fileBytes  = [System.IO.File]::ReadAllBytes($inputFile)
$binString  = ConvertTo-BinaryString -Path $inputFile

$ms  = New-Object System.IO.MemoryStream
$mso  = New-Object System.IO.MemoryStream
$pos = $lastlength = $replacements = 0

foreach ($m in $re.Matches($binString)) {
    $ms.Write($fileBytes, $pos, $m.Index)
    $pos += ($m.Index + $m.Length)
    $lastlength = $m.Length
    $replacements++
    # We need only the first match
    break
}

if ($replacements) {
    # Write unmerged .nw file, $lastlength = 10 is length of the header
    $mso.Write($fileBytes, $pos - $lastlength, $fileBytes.Count - $pos + $lastlength)
 
    [System.IO.File]::WriteAllBytes($outputFile, $ms.ToArray())
    [System.IO.File]::WriteAllBytes($outputData, $mso.ToArray())
}

$ms.Dispose()
$mso.Dispose()

if ($replacements) {
    if ($Unpack) {
        $outfolder = (Get-Item -Path ".\").FullName
        Write-Host -NoNewline "Unpacking $outputData"
        [Reflection.Assembly]::LoadWithPartialName('System.IO.Compression.FileSystem') | Out-Null
        $zipFile = [IO.Compression.ZipFile]::OpenRead($outputData)
        foreach ($packed in $zipFile.Entries) {
            $file = Join-Path -Path $outfolder -ChildPath $packed.FullName
            if ($file.Substring($file.get_Length()-1) -eq "\") {
                # This is directory, don't extract it as file and create if not exist
                if (-Not (Test-Path $file)) {
                    New-Item -ItemType Directory -Path $file | Out-Null
                }
                continue
            }
            Write-Host -NoNewline "."
            [IO.Compression.ZipFileExtensions]::ExtractToFile($packed, $file, $true)
        }  
        $zipFile.Dispose()
        Write-Host ""
        Write-Host "$replacements replacement(s) made, $outputData written and unpacked."
    } else {
        Write-Host "$replacements replacement(s) made and $outputData written."
    }
} else {
    Write-Host "Byte sequence not found."
    Rename-Item -Path $inputFile -NewName $outputFile
}

tyranocut.py

#!/usr/bin/env python
import sys, zipfile, os, mmap

def main():
    if len(sys.argv) != 2:
        print (f'Combined TyranoBuilder executable data extractor v1.0')
        print (f'Usage: {os.path.basename(__file__)} game.exe')
        return

    filename = sys.argv[1]
    if os.path.isfile(filename):
        print (f'Extracting {filename}... ', end='', flush=True)
        with open(filename, 'rb') as f:
            try:
                with zipfile.ZipFile(f) as zf:
                    zf.extractall()
                    print ('OK')
            except Exception as e:
                print (f'FAILED ({e})')
                return

        newname = os.path.join(os.path.dirname(filename), os.path.splitext(os.path.basename(filename))[0] + '_unpacked.exe')
        print (f'Writing cleaned exe {newname}... ', end='', flush=True)
        try:
            with open(filename, "r+b") as f:
                mm = mmap.mmap(f.fileno(), 0)
                found = mm.find(b'\x50\x4B\x03\x04\x0A\x00\x00\x00\x00\x00')
                #print(found + " ", end='')
                if found == -1:
                    print('FAILED (not found)')
                    return
                mm.seek(0)
                with open(newname, "wb") as new:
                    new.write(mm.read(found))
                print ('OK')
        except Exception as e:
            print (f'FAILED ({e})')

    else:
        print (f'{filename} is not found.')

if __name__ == "__main__":
    main()