using System;
namespace SPSolutions
{
	public class PagingCalculator
	{
		private int _numberOfRecords;
		private int _pageSize;
		private int _pageNumber;
		public int NumberOfRecords
		{
			get
			{
				return this._numberOfRecords;
			}
			set
			{
				this._numberOfRecords = value;
			}
		}
		public int PageSize
		{
			get
			{
				return this._pageSize;
			}
			set
			{
				this._pageSize = value;
			}
		}
		public int PageNumber
		{
			get
			{
				return this._pageNumber;
			}
			set
			{
				this._pageNumber = value;
			}
		}
		public int NumberOfPages
		{
			get
			{
				if (this.PageSize == 0 || this.NumberOfRecords == 0)
				{
					return 0;
				}
				return (this.NumberOfRecords + this.PageSize - 1) / this.PageSize;
			}
		}
		public int PreviousPage
		{
			get
			{
				if (this.PageNumber <= 1)
				{
					return 1;
				}
				return this.PageNumber - 1;
			}
		}
		public bool HasPreviousPage
		{
			get
			{
				return this.PageNumber > 1;
			}
		}
		public int NextPage
		{
			get
			{
				if (this.PageNumber >= this.NumberOfPages)
				{
					return this.NumberOfPages;
				}
				return this.PageNumber + 1;
			}
		}
		public bool HasNextPage
		{
			get
			{
				return this.PageNumber < this.NumberOfPages;
			}
		}
		public int BeginningIndex
		{
			get
			{
				return this.PageSize * (this.PageNumber - 1);
			}
		}
		public int EndingIndex
		{
			get
			{
				if (this.NumberOfRecords == 0)
				{
					return -1;
				}
				int num = this.BeginningIndex + this.PageSize - 1;
				if (num >= this.NumberOfRecords - 1)
				{
					return this.NumberOfRecords - 1;
				}
				return num;
			}
		}
		public PagingCalculator()
		{
		}
		public PagingCalculator(int numberOfRecords, int pageSize) : this(numberOfRecords, pageSize, 1)
		{
		}
		public PagingCalculator(int numberOfRecords, int pageSize, int pageNumber)
		{
			if (numberOfRecords < 0)
			{
				throw new ArgumentOutOfRangeException("numberOfRecords", numberOfRecords, "Number of records must be greater than zero");
			}
			if (pageSize < 0)
			{
				throw new ArgumentOutOfRangeException("pageSize", pageSize, "Page size must be greater than zero");
			}
			if (pageNumber < 0)
			{
				throw new ArgumentOutOfRangeException("pageNumber", pageNumber, "Page number must be greater than zero");
			}
			this._numberOfRecords = numberOfRecords;
			this._pageSize = pageSize;
			this._pageNumber = pageNumber;
			if (pageNumber > this.NumberOfPages && this.NumberOfPages != 0)
			{
				throw new ArgumentOutOfRangeException("pageNumber", pageNumber, "The page number is bigger than the number of pages.");
			}
		}
	}
}