function Get-TwitterList()
{
	$wc = new-object system.net.webclient

	$site = $wc.DownloadString('http://www.mindofroot.com/powershell-twitterers/')
	
	$previous = @()
	$start = $site.IndexOf('<div class="entrybody">')
	$site = $site.substring($start)
	$start = $site.IndexOf('<ul>')
	$site = $site.substring($start)
	$end = $site.IndexOf('</ul>') + 5
	
	[xml]$doc = $site.substring(0,$end)	
	$results = $doc.ul.li | select @{name='Name';Expression={$_.a.'#text'}}, @{name='TwitterURL';Expression={$_.a.href}}, @{name='UserName';Expression={$_.a.href -replace 'http://twitter.com/'}}
	$results = $results[1..($results.count-1)]
	return $results
}

function Get-TwitterFriends()
{
	param ($username, $password)
	$cred = New-Object System.Net.NetworkCredential -argumentList $username, $password
	
	$wc = new-object System.Net.WebClient
	$wc.Credentials = $cred
	
	$nbrofpeople = 0
	$page = "?page="
	$names = @()
	
	
	$twitter = "http://twitter.com/statuses/"
	$friends = $twitter + "friends.xml"
	
	$url = $friends
	
	do {
		
		if ($nbrofpeople -gt 0)
		{
			$url = $friends+$page+($nbrofpeople/100 +1)
		}
	
		[xml]$nameslist = $wc.DownloadString($url)
	
		foreach ($one in $nameslist.users.user)
		{
			$user = "" | select name, username, twitterurl, linkurl
			$user.name = $one.name
			$user.username = $one.screen_name
			$user.twitterurl = "http://twitter.com/$($one.screen_name)"
			$user.linkurl = $one.url
			$names += $user
		}
	
		$nbrofpeople += 100
	} while ($names.count -eq $nbrofpeople)
	
	return $names
}

function Add-TwitterFriend()
{
	param($username, $password)
	begin
	{
		$baseurl = 'http://twitter.com/friendships/create/{0}.xml'
		$cred = New-Object System.Net.NetworkCredential -ArgumentList $username,$password
	}
	process
	{
		$url = $baseurl -f $_.UserName
		
		$request = [Net.WebRequest]::Create($url)
		
		$request.ServicePoint.Expect100Continue = $false
		
		$request.Credentials = $cred
		$request.ContentType = "application/x-www-form-urlencoded"
		$request.Method = "POST"
	
		$bytes = [System.Text.Encoding]::ASCII.GetBytes('follow=true')
		
		$request.ContentLength = $bytes.Length
		
		$requestStream = [System.IO.Stream]$request.GetRequestStream()
		$requestStream.write($bytes, 0, $bytes.Length)
		
		$response = $request.GetResponse()    
	
		if ($response) 
		{
			$reader = [System.IO.StreamReader]$response.GetResponseStream()
			([xml]$reader.ReadToEnd()).status
		}
		else 
		{
			Write-Warning "Oops! There was a problem with your request."
			Write-Warning $Error[0] | select *
		}
	}
}

$TwitterUserName=Read-Host "Enter your Twitter Accountname"
$twitterpassword=Read-Host "Enter your Twitter Password"


$friends = Get-TwitterFriends $TwitterUserName $twitterpassword

$friendlist=@()
$friends | foreach {$friendlist+=$_.TwitterURL}
#filter your own name
$list=Get-TwitterList | where {$_.username -notmatch $twitterusername}

foreach ($item in $list) {
if ($friendlist -notcontains $item.Twitterurl) {
Write-Host ("Adding {0} ({1})" -f $item.name,$item.twitterurl) -fore RED
$item | Add-TwitterFriend $TwitterUserName $twitterpassword
}
}