function Get-Tag {
    <#
        .SYNOPSIS

        Return address tag.

        .DESCRIPTION

        Return address tag by id, address object or subnetwork object. Or leave it empty at take all tags at once.
    #>
    [CmdletBinding(DefaultParameterSetName="NoParams")]
    [OutputType([PS.IPAM.Tag])]
    param (
        [parameter(
            Mandatory=$false,
            ValueFromPipeline=$true,
            ValueFromPipelineByPropertyName=$true,
            Position=0,
            ParameterSetName="ByID"
        )]
        [ValidateNotNullOrEmpty()]
        [int]
        $Id,
        [parameter(
            Mandatory=$false,
            ValueFromPipeline=$true,
            ValueFromPipelineByPropertyName=$true,
            Position=0,
            ParameterSetName="ByAddressObject"
        )]
        [ValidateNotNullOrEmpty()]
        [PS.IPAM.Address]
        $AddressObject,
        [parameter(
            Mandatory=$false,
            ValueFromPipeline=$true,
            ValueFromPipelineByPropertyName=$true,
            Position=0,
            ParameterSetName="BySubnetObject"
        )]
        [ValidateNotNullOrEmpty()]
        [PS.IPAM.Subnetwork]
        $SubnetObject
    )
    process {
        $_params = @{
            Controller = [PS.IPAM.controllers]::addresses
            Method     = "GET"
            Type       = [PS.IPAM.types]::tag
        }
        $_identifiers = @("tags")
        switch ($PSCmdlet.ParameterSetName) {
            "ByID"            { $_identifiers += $Id; break  }
            "ByAddressObject" { 
                if ($AddressObject.TagId) {
                    $_identifiers += $AddressObject.TagId
                } else {
                    return $null
                }
                break
             }
             "BySubnetObject" {
                if ($SubnetObject.TagId) {
                    $_identifiers += $SubnetObject.TagId
                } else {
                    return $null
                }
                break
             }
        }
        $_params.Add("Identifiers",$_identifiers)

        Invoke-Request @_params
    }
}
Export-ModuleMember -Function Get-Tag