using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace LQKJ.WebApi.Stub
{
    /// <summary>
    /// 分页工具类
    /// </summary>
    /// <typeparam name="T"></typeparam>
   public class PaginatedList<T>:List<T>
    {
        public PaginatedList(List<T> items,int count,int pageIndex,int pageSize)
        {
            PageIndex = pageIndex;
            TotalPages = (int)Math.Ceiling(count / (double)pageSize);
            this.AddRange(items);
        }

        public int PageIndex { get; private set; }
        public int TotalPages { get; private set; }
        //public bool HasPreviousPage => PageIndex > 1;

        //public bool HasNextPage => PageIndex < TotalPages;

        public static  PaginatedList<T> Create(
            IEnumerable<T> source, int pageIndex, int pageSize)
        {
            var count =  source.Count();
            var items =  source.Skip(
                (pageIndex - 1) * pageSize)
                .Take(pageSize).ToList();
            return new PaginatedList<T>(items, count, pageIndex, pageSize);
        }

    }
}
