MVP Dependency Chaining Framework

using System;
using System.Collections.Generic;
using System.Text;
using MVPChainingFactory.View;

/************************************************************************************
*
* Copyright � 2007 Rohit Gadagkar
*
* This software is provided 'as-is', without any explicit or implied warranty. 
*
* Permission is granted to anyone to use this software for any purpose, including
* commercial applications, and to alter it and redistribute it freely, subject to the
* following restrictions:
*
* 1. The origin of this software must not be misrepresented. You must not claim that
* you wrote the original software. If you use this software in a product, 
* the following acknowledgement in the product documentation is required.
*
* "Portions Copyright � 2007 Rohit Gadagkar"
*
* 2. Altered source versions must be plainly marked as such, and must not be
* misrepresented as being the original software.
*
************************************************************************************/

namespace MVPChainingFactory.Presenters
{
    public abstract class Presenter
    {        
        private IView _view;
        private Presenter _next;
        private PresenterChainMode _chainMode;
        private bool _hasProcessedRequest;

        #region ABSTRACT Methods that must be implemented in derivatives
        
        protected abstract bool CanHandleRequest();
        protected abstract void ProcessRequest();
        
        #endregion
        
        public Presenter(IView view, PresenterChainMode chainMode)
        {
            _view = view; _chainMode = chainMode;
        }

        public Presenter(IView view) : this(view, PresenterChainMode.Break) {}

        public Presenter() : this(null) { }

        public PresenterChainMode ChainMode
        {
            get { return _chainMode; }
            set { _chainMode = value; }
        }

        public Presenter Next
        {
            get { return _next; }
            set { _next = value; }
        }

        public IView View
        {
            get { return _view; }
            set { _view = value; }
        }

        internal bool HasProcessedRequest
        {
            get { return _hasProcessedRequest; }
        }

        public virtual void HandleRequest()
        {
            if (CanHandleRequest())
            {
                if (ChainMode == PresenterChainMode.Break)
                {
                    ProcessRequest();
                    _hasProcessedRequest = true;
                    return;
                }
                else { ProcessRequest(); _hasProcessedRequest = true; }
            }
            if(Next != null) Next.HandleRequest();
        }
    }
}