My Personal Commander Variant

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Management.Automation.Runspaces;
using System.Collections.ObjectModel;
using System.IO;
using Lobster.Components.PowerShell;

namespace Lobster.PowerShell
{
    [System.ComponentModel.Composition.Export(typeof(IShellScript))]
    public abstract class ShellScriptBase : IShellScript
    {
        protected Runspace Runspace {get; private set;}
        protected Pipeline Pipeline { get; private set; }

        public Collection<object> Results { get; protected set; }

        public abstract event Action<IShellScript> OperationCompleted;

        public bool IsValid
        {
            get;
            protected set;
        }

        public string ValidityMessage
        {
            get;
            protected set;
        }

        public ShellScriptBase()
        {
            try
            {
                Results = null;

                // create Powershell runspace
                Runspace = RunspaceFactory.CreateRunspace();

                // open it
                Runspace.Open();

                // create a pipeline and feed it the script text
                Pipeline = Runspace.CreatePipeline();

                IsValid = true;
            }
            catch (Exception e)
            {
                ValidityMessage = "Error in ShellScriptBase.Ctor: " + e.ToString();
                IsValid = false;
            }
        }

        public void AddParameter(string name, object value)
        {
            try
            {
                if (!IsValid) return;
                Runspace.SessionStateProxy.SetVariable(name, value);
            }
            catch (Exception e)
            {
                ValidityMessage = "Error in ShellScriptBase.AddParameter: " + e.ToString();
                IsValid = false;
            }
        }

        public void AddInput(object value)
        {
            try
            {
                if (!IsValid) return;
                Pipeline.Input.Write(value);
            }
            catch (Exception e)
            {
                ValidityMessage = "Error in ShellScriptBase.AddInput: " + e.ToString();
                IsValid = false;
            }
        }


        public bool AddScriptFromFile(string pathName)
        {
            try
            {
                if (!IsValid) return false;

                var script = File.ReadAllText(pathName);
                Pipeline.Commands.AddScript(script);
            }
            catch (Exception e)
            {
                ValidityMessage = "Error in ShellScriptBase.AddScriptFromFile: " + e.ToString();
                IsValid = false;
            }
            return IsValid;
        }



        public abstract bool Run();

        public abstract ShellScriptType Type
        {
            get;
        }

        public abstract object Clone();
    }
}