DSInternals/Src/DSInternals.PowerShell/Commands/Base/ADReplPrincipalCommandBase.cs

using System.Management.Automation;
using System.Security.Principal;

namespace DSInternals.PowerShell.Commands
{
    public abstract class ADReplPrincipalCommandBase : ADReplObjectCommandBase
    {
        protected const string ParameterSetByName = "ByName";
        protected const string ParameterSetByUPN = "ByUPN";
        protected const string ParameterSetBySid = "BySID";

        #region Parameters

        [Parameter(
            Mandatory = true,
            Position = 0,
            ValueFromPipeline = true,
            ValueFromPipelineByPropertyName = true,
            ParameterSetName = ParameterSetByName
        )]
        [ValidateNotNullOrEmpty]
        [Alias("Login", "sam", "AccountName", "User")]
        public string SamAccountName
        {
            get;
            set;
        }

        [Parameter(
            Mandatory = false,
            Position = 1,
            ParameterSetName = ParameterSetByName
        )]
        [ValidateNotNullOrEmpty]
        [Alias("AccountDomain", "UserDomain")]
        public string Domain
        {
            get;
            set;
        }

        [Parameter(
            Mandatory = true,
            ValueFromPipelineByPropertyName = true,
            ParameterSetName = ParameterSetByUPN
        )]
        [ValidateNotNullOrEmpty]
        [Alias("UPN")]
        public string UserPrincipalName
        {
            get;
            set;
        }

        [Parameter(
            Mandatory = true,
            ValueFromPipelineByPropertyName = true,
            ParameterSetName = ParameterSetBySid
        )]
        [ValidateNotNullOrEmpty]
        [Alias("Sid")]
        public SecurityIdentifier ObjectSid
        {
            get;
            set;
        }

        #endregion Parameters

        protected override void BeginProcessing()
        {
            base.BeginProcessing();

            if (ParameterSetName == ParameterSetByName)
            {
                if(string.IsNullOrEmpty(this.Domain))
                {
                    // Automatically infer DC's domain name.
                    this.Domain = this.ReplicationClient.NetBIOSDomainName;
                }
                else
                {
                    // User-provided domain name, so a sanity check is necessary.
                    this.ValidateDomainName();
                }
            }
        }

        protected void ValidateDomainName()
        {
            if (this.Domain.Contains("."))
            {
                // This is not a hard check, because dots are actually allowed in NetBIOS names, although not recommended.
                // TODO: Extract as a resource
                this.WriteWarning("The domain name supplied appears to be a DNS name instead of NetBIOS name.");
            }
        }
    }
}