using Microsoft.SharePoint;
using Microsoft.SharePoint.Utilities;
using System;
using System.Globalization;
using System.Runtime.CompilerServices;
using System.Threading;
using System.Web.UI;
using System.Web.UI.WebControls;
namespace SPSolutions.SharePoint.WebControls
{
    public class SPManualPager : WebControl, IPostBackEventHandler
    {
        private PagingCalculator m_pagingCalculator;
        private static readonly string NextPageCommand = "previouspage";
        private static readonly string PreviousPageCommand = "nextpage";
        public event EventHandler ClickNext;

        //[MethodImpl(MethodImplOptions.Synchronized)]
        //add
        //{
        //    //this.ClickNext = (EventHandler)Delegate.Combine(this.ClickNext, value);
        //    this.ClickNext += value;
        //}
        //[MethodImpl(MethodImplOptions.Synchronized)]
        //remove
        //{
        //    //this.ClickNext = (EventHandler)Delegate.Remove(this.ClickNext, value);
        //    this.ClickNext -= value;
        //}

        public event EventHandler ClickPrevious;
        //{
        //    [MethodImpl(MethodImplOptions.Synchronized)]
        //    add
        //    {
        //        //this.ClickPrevious = (EventHandler)Delegate.Combine(this.ClickPrevious, value);
        //        this.ClickPrevious += value;
        //    }
        //    [MethodImpl(MethodImplOptions.Synchronized)]
        //    remove
        //    {
        //        //this.ClickPrevious = (EventHandler)Delegate.Remove(this.ClickPrevious, value);
        //        this.ClickPrevious -= value;
        //    }
        //}
        public int PageNumber
        {
            get
            {
                return this.ParseIntegerFromViewState(this.ViewState["PageNumber"], 1);
            }
            set
            {
                this.ViewState["PageNumber"] = value;
            }
        }
        public int PageSize
        {
            get
            {
                return this.ParseIntegerFromViewState(this.ViewState["PageSize"], 10);
            }
            set
            {
                this.ViewState["PageSize"] = value;
            }
        }
        public int NumberOfRecords
        {
            get
            {
                return this.ParseIntegerFromViewState(this.ViewState["NumberOfRecords"], 0);
            }
            set
            {
                this.ViewState["NumberOfRecords"] = value;
            }
        }
        public int LowestDataItemIndex
        {
            get
            {
                return this.m_pagingCalculator.BeginningIndex;
            }
        }
        public int HighestDataItemIndex
        {
            get
            {
                return this.m_pagingCalculator.EndingIndex;
            }
        }
        private static string PreviousImageUrl
        {
            get
            {
                return "/_layouts/15/" + SPContext.Current.Web.Language.ToString(CultureInfo.InvariantCulture) + "/images/prev.gif";
            }
        }
        public bool PreviousPageLinkIsEnabled
        {
            get
            {
                return this.m_pagingCalculator.HasPreviousPage;
            }
        }
        private static string NextImageUrl
        {
            get
            {
                return "/_layouts/15/" + SPContext.Current.Web.Language.ToString(CultureInfo.InvariantCulture) + "/images/next.gif";
            }
        }
        public bool NextPageLinkIsEnabled
        {
            get
            {
                return this.m_pagingCalculator.HasNextPage;
            }
        }
        public SPManualPager()
        {
            this.m_pagingCalculator = new PagingCalculator(1, 10, 0);
        }
        private int ParseIntegerFromViewState(object viewStateObject, int defaultValue)
        {
            if (viewStateObject == null)
            {
                return defaultValue;
            }
            if (viewStateObject is int)
            {
                return (int)viewStateObject;
            }
            int result;
            if (!int.TryParse(viewStateObject.ToString(), out result))
            {
                return defaultValue;
            }
            return result;
        }
        protected override void Render(HtmlTextWriter output)
        {
            this.m_pagingCalculator.NumberOfRecords = this.NumberOfRecords;
            this.m_pagingCalculator.PageSize = this.PageSize;
            this.m_pagingCalculator.PageNumber = this.PageNumber;
            if (this.LowestDataItemIndex >= 0 && this.HighestDataItemIndex >= 0)
            {
                output.Write("<table cellpadding=\"0\" cellspacing=\"0\" border=\"0\"><tr><td valign=\"center\">");
                this.RenderImage(output, this.PreviousPageLinkIsEnabled, SPManualPager.PreviousPageCommand, SPManualPager.PreviousImageUrl, "/_layouts/15/images/blank.gif", SPResource.GetString("multipagesPreviousPage", new object[0]));
                output.Write("</td><td valign=\"center\" class=\"ms-listheaderlabel\" nowrap>");
                output.Write("&nbsp;");
                output.Write((this.LowestDataItemIndex + 1).ToString(Thread.CurrentThread.CurrentCulture.NumberFormat));
                output.Write("-");
                output.Write((this.HighestDataItemIndex + 1).ToString(Thread.CurrentThread.CurrentCulture.NumberFormat));
                output.Write("&nbsp;</td><td valign=\"center\">");
                this.RenderImage(output, this.NextPageLinkIsEnabled, SPManualPager.NextPageCommand, SPManualPager.NextImageUrl, "/_layouts/15/images/blank.gif", SPResource.GetString("multipagesNextPage", new object[0]));
                output.Write("</td></tr></table>");
            }
        }
        private void RenderImage(HtmlTextWriter output, bool isEnabled, string postbackEventArgument, string enabledImageUrl, string disabledImageUrl, string toolTip)
        {
            string value = disabledImageUrl;
            if (isEnabled)
            {
                output.Write("<a href=\"#\" onclick=\"");
                output.Write(this.Page.ClientScript.GetPostBackEventReference(this, postbackEventArgument));
                output.Write("; return false;\">");
                value = enabledImageUrl;
            }
            output.Write("<img src=\"");
            output.Write(value);
            output.Write("\" border=\"0\" alt=\"");
            output.Write(SPEncode.HtmlEncode(toolTip));
            output.Write("\"/>");
            if (isEnabled)
            {
                output.Write("</a>");
            }
        }
        protected virtual void OnClickNext(EventArgs args)
        {
            this.PageNumber++;
            if (ClickNext != null)
            {
                this.ClickNext(this, args);
            }
        }
        protected virtual void OnClickPrevious(EventArgs args)
        {
            this.PageNumber--;
            if (this.ClickPrevious != null)
            {
                this.ClickPrevious(this, args);
            }
        }
        public void RaisePostBackEvent(string eventArgument)
        {
            if (eventArgument == null)
            {
                throw new ArgumentNullException("eventArgument");
            }
            string a = eventArgument.ToLower(CultureInfo.InvariantCulture);
            EventArgs args = new EventArgs();
            if (a == SPManualPager.PreviousPageCommand)
            {
                this.OnClickPrevious(args);
                return;
            }
            if (a == SPManualPager.NextPageCommand)
            {
                this.OnClickNext(args);
            }
        }
    }
}