Open Source Extensible Enterprise n-tier Application Framework with Multilayered Architecture

using System;
using System.Web.UI;
using SiberTek.Xenta.Presentation.Resources;
using SiberTek.Xenta.Web.Controls;
using System.Web.UI.WebControls;

namespace SiberTek.Xenta.Web.Admin.Modules
{
    public partial class DataPager : UserControlBase, ICommandHandler
    {
        #region Fields
        private UserControlBase _tgtControl;
        #endregion

        #region Constructors
        public DataPager()
        {
            _tgtControl = null;
        }
        #endregion

        #region Properties
        public string TargetControlID
        {
            get
            {
                return Convert.ToString(ViewState["TargetControlID"]);
            }
            set
            {
                ViewState["TargetControlID"] = value;
            }
        }

        public override bool Visible
        {
            get
            {
                return base.Visible && ((TargertControl as IPageable) != null) && ((TargertControl as IPageable).PageCount > 1);
            }
            set
            {
                base.Visible = value;
            }
        }

        private UserControlBase TargertControl
        {
            get
            {
                if(_tgtControl == null)
                {
                    _tgtControl = Page.FindControlRecursive(TargetControlID) as UserControlBase;
                }
                return _tgtControl;
            }
        }
        #endregion

        #region Handlers
        protected override void OnInit(EventArgs e)
        {
            if(!IsPostBack)
            {
                btnNext.CommandName = "Next";
                btnPrev.CommandName = "Previous";
                btnPrev.ToolTip = StringManager.GetString("Admin.DataPager.btnPrev.ToolTip");
                lblPage.Text = StringManager.GetString("Admin.DataPager.lblPage.Text");
                lblOf.Text = StringManager.GetString("Admin.DataPager.lblOf.Text");
                btnNext.ToolTip = StringManager.GetString("Admin.DataPager.btnNext.ToolTip");
            }

            btnNext.Command += OnCommand;
            btnPrev.Command += OnCommand;

            base.OnInit(e);
        }

        protected override void OnPreRender(EventArgs e)
        {
            IPageable pageableView = TargertControl as IPageable;

            if(pageableView != null)
            {
                if(pageableView.PageCount > 1)
                {
                    btnPrev.Visible = (pageableView.PageIndex - 1 >= 0);
                    txtPageIndex.Text = (pageableView.PageIndex + 1).ToString();
                    lblPageCount.Text = pageableView.PageCount.ToString();
                    btnNext.Visible = (pageableView.PageIndex + 1 < pageableView.PageCount);
                    Visible = true;
                }
            }
            base.OnPreRender(e);
        }

        protected void TxtPageIndex_OnTextChanged(object sender, EventArgs e)
        {
            int newIndex = 0;

            if(Int32.TryParse(txtPageIndex.Text, out newIndex))
            {
                IPageable pageableView = TargertControl as IPageable;

                if(pageableView != null)
                {
                    if(newIndex <= 1)
                    {
                        newIndex = 1;
                    }
                    else
                    {
                        if(newIndex >= pageableView.PageCount)
                        {
                            newIndex = pageableView.PageCount;
                        }
                    }
                    pageableView.PageIndex = newIndex - 1;
                    TargertControl.BindData();
                }
            }
        }

        public void OnCommand(object sender, CommandEventArgs e)
        {
            switch(e.CommandName)
            {
                case "Previous":
                    {
                        IPageable pageableView = TargertControl as IPageable;

                        if(pageableView != null)
                        {
                            pageableView.PageIndex -= 1;
                            TargertControl.BindData();
                        }
                    }
                    break;
                case "Next":
                    {
                        IPageable pageableView = TargertControl as IPageable;

                        if(pageableView != null)
                        {
                            pageableView.PageIndex += 1;
                            TargertControl.BindData();
                        }
                    }
                    break;
            }
        }
        #endregion
    }
}