Get-ChessScore.ps1

function Get-ChessScores
{
[cmdletbinding()]
Param(
    [Parameter(ValueFromPipeline)]
    [string]$RootPath
)

Begin {
    $SharpCode = @'
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

public static class ChessResult
{
    public static System.Collections.Hashtable GetResults(string fullFileName)
    {
        System.Collections.Hashtable hash = new System.Collections.Hashtable();
        hash.Add("White", 0);
        hash.Add("Black", 0);
        hash.Add("Draw", 0);

        List<byte> ByteList = new List<byte>();

        var allBytes = System.IO.File.ReadAllBytes(fullFileName);
        
        int resultsBracketIndex = 0;
        int white = 0;
        int black = 0;
        int draw = 0;
        string resultString = string.Empty;
        for (int i = 0; i < allBytes.Length; i++)            
        {
            if (allBytes[i] == 91 && allBytes[(i + 1)] == 82 && allBytes[(i + 2)] == 101)
            {
                resultsBracketIndex = i;
            }
            if (allBytes[i] == 93 && resultsBracketIndex != 0)
            {
                resultsBracketIndex = 0;
                ByteList.Add(allBytes[i]);
                int indexx = ByteList.IndexOf(34);                
                if (ByteList[indexx + 1] == 49 && ByteList[indexx + 2] == 45) white++;
                if (ByteList[indexx + 1] == 48 && ByteList[indexx + 2] == 45) black++;
                if (ByteList[indexx + 1] == 49 && ByteList[indexx + 2] == 47) draw++;
                ByteList.Clear();
            }
            if (resultsBracketIndex != 0)
            {
                ByteList.Add(allBytes[i]);
            }            
        }
        hash["White"] = white;
        hash["Black"] = black;
        hash["Draw"] = draw;
        return hash;
    }
}
'@
    
    Add-Type $SharpCode -ErrorAction SilentlyContinue 

    $hash = @{
        White = 0
        Black = 0
        Draw = 0
    }
    [gc]::Collect()
}

Process {
    $Files = Get-ChildItem -Path $RootPath -Filter *.pgn -Recurse
    
    foreach($file in $Files)
    {
        $FileResult = [ChessResult]::GetResults($file.fullname)
        $hash["White"] += $FileResult["White"]
        $hash["Black"] += $FileResult["Black"]
        $hash["Draw"] += $FileResult["Draw"]    
    }    
}

End {
    return $hash
}
}