PixelDragonsMVC.NET - An open source MVC framework

/***********************************************************
 * 
 * Copyright 2007 Pixel Dragons Ltd. All rights reserved.
 * 
 * http://www.codeplex.com/PixelDragonsMVC for licence, more
 * information and latest source code. 
 * 
 * Check out our other stuff at http://www.pixeldragons.com
 * 
 ***********************************************************/

using System;
using System.Collections;
using System.Collections.Generic;

using NHibernate.Expression;

namespace PixelDragons.MVC.Persistence
{
    public enum SortDirection { None, Ascending, Descending }

	public class PageSettings 
	{
        public PageSettings()
		{
		}

		private Dictionary<string, SortDirection> _columnSorting = null;
        private List<SimpleExpression> _filterExpressions = null;
		private int _pageSize = 10;
        private int _currentPageIndex = 0;
		private int _totalPageCount = 0;
		private int _totalItemCount = 0;
		private bool _calculateTotal = false;

        public Dictionary<string, SortDirection> ColumnSorting
		{
			get 
			{
                if (_columnSorting == null)
				{
                    _columnSorting = new Dictionary<string, SortDirection>();
				}

                return _columnSorting; 
			}
            set { _columnSorting = value; }
		}

		public List<SimpleExpression> FilterExpressions
		{
			get 
			{ 
				if (_filterExpressions == null)
				{
                    _filterExpressions = new List<SimpleExpression>();
				}

				return _filterExpressions; 
			}
			set { _filterExpressions = value; }
		}

		public int PageSize
		{
			get { return _pageSize; }
			set 
			{ 
				if (_pageSize < 1)
				{
					throw new ArgumentOutOfRangeException("PageSize", _pageSize, "Page Size cannot be less than 1");
				}
				_pageSize = value; 
			}
		}

        public int CurrentPageIndex
		{
            get { return _currentPageIndex; }
            set { _currentPageIndex = value; }
		}

		public int TotalPageCount
		{
			get { return _totalPageCount; }
		}

        public int TotalItemCount
		{
            get { return _totalItemCount; }
			set 
			{
                if (_totalItemCount < 0)
				{
                    throw new ArgumentOutOfRangeException("ItemCount", _totalItemCount, "Item Count cannot be less than zero");
				}

                _totalItemCount = value;
                _totalPageCount = _totalItemCount / PageSize;
                if ((_totalItemCount % PageSize) > 0)
				{
					_totalPageCount ++;
				}
				//check if current page is still valid
                if (CurrentPageIndex > MaxPageIndex)
				{
                    CurrentPageIndex = MaxPageIndex;
				}
			}
		}

		public bool IsFirstPage()
		{
            return CurrentPageIndex == 0;
		}

		public bool IsLastPage()
		{
            return CurrentPageIndex == MaxPageIndex;
		}

		public int MaxPageIndex
		{
			get
			{
				return TotalPageCount - 1;
			}
		}

		public bool CalculateTotal
		{
			get { return _calculateTotal; }
			set { _calculateTotal = value; }
		}
	}
}