Create web-safe folder from portion of filename taken by supplied regex and move file into it.

file2folder.ps1

<#
  For each file:
  1. take filename or portion of it,
  2. create web-safe folder from template and filename match,
  3. move file into new folder.

  e.g. -format "arnpriorbylaw{0}" -take "(?m)(?i)\s*by-law\s*-\s*(\d{4}A*-\d{2})\s*-\s*.+$" => 'arnpriorbylaw1234-00'
#>

param(
  [string]$in,
  [string]$outdir,
  [regex]$take = "(.+)",
  [string]$format = "{0}"
)

function WebSafe([string]$s) {
    return $s.ToLowerInvariant().Replace(" ", "-").Replace("&", "-")
}

$file = get-childitem $in

# take filename or portion
$file.BaseName -match $take | out-null
$folder = WebSafe(($format -f $matches[1]))

$folderdir = [System.IO.Path]::Combine($outdir, $folder)

# rename original file temporarily in case folder name == filename
$filename = $file.Name
$temp = "$($file.FullName).tmp"
move-item $file.FullName $temp -force

# make absolutely brand new folder, destroying any pre-existing folder of that name
if (test-path $folderdir) {
  get-childitem $folderdir -force -recurse | remove-item -force -recurse
  remove-item $folderdir -force
}
mkdir $folderdir | out-null

# move file to new folder
$outfile = [System.IO.Path]::Combine($folderdir, $filename)
move-item $temp $outfile -force