param (
  [parameter(Mandatory=$true, HelpMessage="Cluster IP address")]
  [string]$Cluster,

  [parameter(Mandatory=$true, HelpMessage="Volume name")]
  [string]$VolumeName,

  [parameter(Mandatory=$true, HelpMessage="Storage Virtual Machine name")]
  [string]$VserverName
)

# connect to cluster
Connect-WfaCluster $Cluster
$lastConnectedCluster = $Cluster

$clusterInfo = Get-NcCluster

# Testing volume existence. As this command doesn't throw exception if
# ErrorAction is 'Stop' and the volume isn't found. So, an explicit check.
$vol = Get-NcVol -Name $VolumeName -Vserver $VserverName
if(!$vol)
{
    throw "Volume '$VolumeName' not found on Storage Virtual Machine '$VserverName'"
}

# Validating that existing vsm relationships in which the target volume is the source
# can be removed from their destination clusters.
# vsm relationships in which the target volume is source
$vsmAsSource = Get-NcSnapmirrorDestination -SourceVolume $volumename #CMW_ADD
# looping through vsm relationships in which the target volume is the source
# and testing credential existence for destination clusters in those relationships
# so we want to remove relationships from the destinations and not from source
if ($vsmAsSource){
    foreach($vsm in $vsmAsSource){
        try{
            $vserverpeer = Get-NcVserverPeer -Vserver $VserverName -PeerVserver $vsm.DestinationVserver
            if ($vserverpeer.PeerCluster -ne $global:CurrentNcController.Name){
                Connect-WfaCluster $vserverpeer.PeerCluster
                $lastConnectedCluster = $vserverpeer.PeerCluster
                }
            Remove-NcSnapmirror -Source $vsm.SourceLocation -Destination $vsm.DestinationLocation -Confirm:$false -ErrorAction Stop
        }
        catch{
           Get-WFALogger -Warn -message $("Could not remove the VSM relationship from " + $VolumeName + "-->" +$vsm.DestinationVserver + ":" + $vsm.DestinationVolume + "  "+$_.Exception.Message)
           try {
                Connect-WfaCluster $Cluster
                if ($vol.state -eq 'offline'){$vol | set-ncvol -online}
                $vsm | Invoke-NcSnapmirrorRelease -RelationshipInfoOnly -Confirm:$false
                $vol | set-ncvol -offline
           }
           catch{
                Get-WFALogger -Warn -message $("Could not release the VSM relationship from " + $VolumeName + "-->" +$vsm.DestinationVserver + ":" + $vsm.DestinationVolume + "  "+$_.Exception.Message)
           }
           
        }
    }
}

# removing vsm relationships in which the target volume is destination
# connect back to original target cluster only if the last connected cluster was another
# comparing based on hostname and ipaddress
if($lastConnectedCluster -ne $Cluster -and $lastConnectedCluster -ne $clusterInfo.ClusterName)
{
    Connect-WfaCluster $Cluster
}

$vsmAsDestination = Get-NcSnapmirror | where{$_.DestinationVserver -eq $VServerName -and $_.DestinationVolume -eq $VolumeName -and ($_.DestinationCluster -eq $Cluster -or $_.DestinationCluster -eq $clusterInfo.ClusterName)}
if($vsmAsDestination)
{
    if($vsmAsDestination.GetType().BaseType.Name -eq "Array")
    {
            $totalVsmAsDestination = $vsmAsDestination.Length
    }
    else
    {
        $totalVsmAsDestination = 1
    }

    $totalLocalRemovedVsms = 0
    foreach($vsm in $vsmAsDestination)
    {
        try{
            Remove-NcSnapmirror -Source $vsm.SourceLocation -Destination $vsm.DestinationLocation -Confirm:$false -ErrorAction Stop
            Get-WFALogger -Info -Message $("VSM Relationship successfully removed on local cluster '" + $vsm.DestinationCluster + "' (source: " + $vsm.SourceLocation + ", destination: " + $vsm.DestinationLocation + ")")
            $totalLocalRemovedVsms++
        }
        catch
        {
            Get-WFALogger -Warn -message $("Unable to remove relationship on local cluster (source: " + $vsm.SourceLocation + ", destination: " + $vsm.DestinationLocation+"). " + $_.Exception.Message)
        }        
    }

    if($totalLocalRemovedVsms -lt $totalVsmAsDestination)
    {
        throw "One or more VSM relationships were not removed. Aborting removal of the volume"
    }
}

# Dismount the volume from the Storage Virtual Machine namespace if it is not the Storage Virtual Machine root volume
if (!$vol.VolumeStateAttributes.IsVserverRoot)
{
	Get-WFALogger -Info -message $("Dismounting volume: " + $VolumeName + " on Storage Virtual Machine " + $VserverName)
	Dismount-NcVol -Name $VolumeName -VserverContext $VserverName -Force -ErrorAction Stop
}

$volState = (Get-NcVol -Name $VolumeName -VserverContext $VserverName).State

if($volState -ne "offline")
{
    Get-WFALogger -Info -message $("Offlining volume: " + $VolumeName + " on Storage Virtual Machine " + $VserverName)
    Set-NcVol -Name $VolumeName -VserverContext $VserverName -Offline -ErrorAction Stop
}

Get-WFALogger -Info -message $("Destroying volume: " + $VolumeName + " on Storage Virtual Machine " + $VserverName)
Remove-NcVol -Name $VolumeName -VserverContext $VserverName -Confirm:$false -ErrorAction Stop