function Add-AvailabilityGroupDatabase{
    param(
        $ServerName,
        $Port = 1433,
        $DatabaseName,
        $AvailabilityGroup
    )
    begin{

    }
    process{

        if(!$ServerName.Contains('.')){
            $ServerName = "$ServerName.$env:USERDNSDOMAIN"
        }
        $srv = new-object Microsoft.SqlServer.Management.smo.Server "$ServerName,$Port"
        $ServerName = $srv.AvailabilityGroups[$AvailabilityGroup].PrimaryReplicaServerName
        $srv.ConnectionContext.Disconnect()
        $srv = new-object Microsoft.SqlServer.Management.smo.Server "$($ServerName).$env:USERDNSDOMAIN,$Port"

        if(!$srv.Databases[$DatabaseName]){
            throw "Could not find a database $DatabaseName on primary replica $ServerName"
        }

        if(!$srv.AvailabilityGroups[$AvailabilityGroup].AvailabilityDatabases.Contains($DatabaseName)){
            [void]$srv.ConnectionContext.ExecuteNonQuery("RESTORE DATABASE [$DatabaseName] WITH RECOVERY;");
            $ADB = New-Object Microsoft.SqlServer.Management.smo.AvailabilityDatabase($srv.AvailabilityGroups[$AvailabilityGroup], $DatabaseName);
            $ADB.Create();
        }
        else{
            Write-Warning "Database $DatabaseName is already an availbility database on server $ServerName."
        }
        
        
        $srv.AvailabilityGroups[$AvailabilityGroup].AvailabilityReplicas | ?{$_.Name -ne $ServerName} | select -expandproperty Name | %{
            $name = $_ 
            try{
                $sec = new-object Microsoft.SqlServer.Management.smo.Server "$($name).$env:USERDNSDOMAIN,$Port"
                $ag = $sec.AvailabilityGroups[$AvailabilityGroup]
                if(!$ag.AvailabilityDatabases[$DatabaseName].IsJoined){
                    $ag.AvailabilityDatabases[$DatabaseName].JoinAvailablityGroup();
                }
                else{
                    Write-Warning "Database $DatabaseName is already an availbility database on server $name."
                }
            }
            catch{
                Write-Error $_ | fl -Force
            }
            finally{
                $sec.ConnectionContext.Disconnect();
            }
        }


        $srv.ConnectionContext.Disconnect()

    }
    end{

    }
}