Convert multiple source files to markdown (for example to feed the markdown to a web based ai)

Convert-SourceToMarkDown.ps1

#requires -version 7.4
function Get-FilesSkippingDirsAndExts {
    param(
        [Parameter(Mandatory)][string]$RootPath,
        [string[]]$SkipNames = @(),
        [string[]]$Extensions = @()  # e.g. @(".cs",".js",".txt") or @("cs","js")
    )

    # Normalize extensions to start with dot and lower-case
    $normExts = $Extensions |
        ForEach-Object {
            if ([string]::IsNullOrWhiteSpace($_)) { continue }
            $e = $_.Trim()
            if ($e.StartsWith('.')) { $e = $e.Substring(1) }
            '.' + $e.ToLowerInvariant()
        }

    $rootDir = [System.IO.DirectoryInfo]::new($RootPath)
    $stack = [System.Collections.Generic.Stack[System.IO.DirectoryInfo]]::new()
    $stack.Push($rootDir)

    while ($stack.Count -gt 0) {
        $dir = $stack.Pop()

        # files
        try {
            foreach ($file in $dir.EnumerateFiles()) {
                if ($normExts.Count -eq 0 -or $normExts -contains $file.Extension.ToLowerInvariant()) {
                    $file
                }
            }
        } catch {
            # ignore access errors
        }

        # subdirectories to descend into
        try {
            foreach ($sub in $dir.EnumerateDirectories()) {
                if ($SkipNames -notcontains $sub.Name) {
                    $stack.Push($sub)
                }
            }
        } catch {
            # ignore access errors
        }
    }
}

$markdownFile = 'd:\source\output.md'
$slnPath = 'd:\source\OnPrem'
$skipFolders = ('obj', 'Properties', 'bin', '.vs')
$sourceExtensionTagMap = @{ 
    '.slnx' = 'xml'
    '.sln' = 'xml'
    '.csproj' = 'xml'
    '.cs' = 'csharp'
    '.json' = 'json' 
    }

$sourceExtensions = ($sourceExtensionTagMap.Keys) #  | ForEach-Object {"$_" }) #-join ', '
$srcFiles = Get-FilesSkippingDirsAndExts -RootPath $slnPath -SkipNames $skipFolders -Extensions $sourceExtensions
#Get-ChildItem -Directory -Path $slnPath -exclude $excludedFolders -recurse | Where-Object { $excludedFolders -notcontains $_.Name }
#| ForEach-Object { Get-ChildItem -Path $_ -Include ($sourceExtensions) -recurse}

$srcFiles | ForEach-Object {
    $RelativePath = Resolve-Path -Path $_ -RelativeBasePath $slnPath -Relative
	$x = $_.Extension
	Write-Output "Processing $x $RelativePath"
	$langTag = $sourceExtensionTagMap[$x]
    Add-Content -Path $markdownFile -Value "## $RelativePath"
    Add-Content -Path $markdownFile -Value "" # a blank line
    Add-Content -Path $markdownFile -Value "~~~$langTag"
    Get-Content -Path $_.FullName | Add-Content -Path $markdownFile
    Add-Content -Path $markdownFile -Value "~~~"
    Add-Content -Path $markdownFile -Value ""
}