FONToMASS downloader

FONToMASS.ps1

#CHANGE⌄
$pages = 869
#CHANGE^


# DON'T CHANGE⌄
Function Get-RedirectedUrl {
    Param (
        [Parameter(Mandatory = $true)]
        [String]$URL
    )
    $request = [System.Net.WebRequest]::Create($url)
    $request.AllowAutoRedirect = $false
    $response = $request.GetResponse()
    If ($response.StatusCode -eq "Found") {
        $response.GetResponseHeader("Location")
    }
}

$BaseURL = "https://vk.com/topic-178186634_39300099?offset="
$outerrange = ($pages -1)  * 20
$reg_expression = '/doc.*'
$dl = New-Object net.webclient

for ($offset = 0; $offset -le $outerrange; $offset += 20) {
    $scraped_links = (Invoke-WebRequest -Uri "$BaseURL$offset").Links.Href  | Get-Unique
    $all_matches = ($scraped_links | Select-String $reg_expression -AllMatches).Matches
    $urls = foreach ($url in $all_matches) {
        $url.Value
    }

    foreach ($URL in $URLS) {
        $FileName = ([System.IO.Path]::GetFileName((Get-RedirectedUrl "https://vk.com$($URL)"))).split('?')[0]
        if (Test-Path -Path ".\$FileName" -PathType Leaf) {
            $add = ([System.IO.Path]::GetRandomFileName().Split('.')[0])
            $FileName = "$FileName-DUP-$add"
        }
        $dl.Downloadfile( "https://vk.com$URL", ".\$FileName")
    }   
}