using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Drawing;
using System.Data;
using System.Text;
using System.Linq;
using System.Threading.Tasks;
using System.Windows.Forms;
using DevExpress.XtraEditors;
using ProjectBase.Data.Pager;

namespace ProjectBase.Controls
{
    public delegate void PageChangedEventHandler(object sender, EventArgs e);
    public delegate void ExportCurrentEventHandler(object sender, EventArgs e);
    public delegate void ExportAllEventHandler(object sender, EventArgs e);

    /// <summary>
    /// 分页工具条用户控件，仅提供分页信息显示及改变页码操作
    /// </summary>
    public partial class Pager : DevExpress.XtraEditors.XtraUserControl
    {
        /// <summary>
        /// 页面切换的时候触发的事件
        /// </summary>
        public event PageChangedEventHandler PageChanged;
        public event ExportCurrentEventHandler ExportCurrent;
        public event ExportAllEventHandler ExportAll;

        private int m_PageSize;
        private int m_PageCount;
        private int m_RecordCount;
        private int m_CurrentPageIndex;
        private bool m_ShowExportButton = true;//是否显示导出按钮

        private PagerInfo pagerInfo = null;

        /// <summary>
        /// 分页信息
        /// </summary>
        public PagerInfo PagerInfo
        {
            get
            {
                if (pagerInfo == null)
                {
                    pagerInfo = new PagerInfo();
                    pagerInfo.RecordCount = this.RecordCount;
                    pagerInfo.CurrenetPageIndex = this.CurrentPageIndex;
                    pagerInfo.PageSize = this.PageSize;

                    pagerInfo.OnPageInfoChanged += new PageInfoChanged(pagerInfo_OnPageInfoChanged);
                }
                else
                {
                    pagerInfo.CurrenetPageIndex = this.CurrentPageIndex;
                }

                return pagerInfo;
            }
        }

        void pagerInfo_OnPageInfoChanged(PagerInfo info)
        {
            this.RecordCount = info.RecordCount;
            this.CurrentPageIndex = info.CurrenetPageIndex;
            this.PageSize = info.PageSize;

            this.InitPageInfo();
        }

        /// <summary> 
        /// 必需的设计器变量。在Designer中
        /// </summary>
        //private System.ComponentModel.Container components = null;

        /// <summary> 
        /// 默认构造函数，设置分页初始信息
        /// </summary>
        public Pager()
        {
            InitializeComponent();
            this.m_PageSize = 50;
            this.m_RecordCount = 0;
            this.m_CurrentPageIndex = 1; //默认为第一页
            this.InitPageInfo();
        }
        /// <summary> 
        /// 带参数的构造函数
        /// <param name="pageSize">每页记录数</param>
        /// <param name="recordCount">总记录数</param>
        /// </summary>
        public Pager(int recordCount, int pageSize)
        {
            InitializeComponent();

            this.m_PageSize = pageSize;
            this.m_RecordCount = recordCount;
            this.m_CurrentPageIndex = 1; //默认为第一页
            this.InitPageInfo();
        }

        /// <summary> 
        /// 清理所有正在使用的资源。在Designer中
        /// </summary>
        //protected override void Dispose(bool disposing)
        //{
        //    if (disposing)
        //    {
        //        if (components != null)
        //        {
        //            components.Dispose();
        //        }
        //    }
        //    base.Dispose(disposing);
        //}

        /// <summary>
        /// 页面变化处理
        /// </summary>
        /// <param name="e"></param>
        protected virtual void OnPageChanged(EventArgs e)
        {
            if (PageChanged != null)
            {
                PageChanged(this, e);
            }
        }

        /// <summary>
        /// 是否显示导出按钮
        /// </summary>
        [Description("是否显示导出按钮。"), DefaultValue(true), Category("分页")]
        public bool ShowExportButton
        {
            get { return m_ShowExportButton; }
            set
            {
                m_ShowExportButton = value;
                this.btn_Export.Visible = value;
                this.btn_ExportCurrent.Visible = value;
            }
        }

        /// <summary>
        /// 设置或获取一页中显示的记录数目
        /// </summary>
        [Description("设置或获取一页中显示的记录数目"), DefaultValue(50), Category("分页")]
        public int PageSize
        {
            set
            {
                this.m_PageSize = value;
            }
            get
            {
                return this.m_PageSize;
            }
        }

        /// <summary>
        /// 获取记录总页数
        /// </summary>
        [Description("获取记录总页数"), DefaultValue(0), Category("分页")]
        public int PageCount
        {
            get
            {
                return this.m_PageCount;
            }
        }

        /// <summary>
        /// 设置或获取记录总数
        /// </summary>
        [Description("设置或获取记录总数"), Category("分页")]
        public int RecordCount
        {
            set
            {
                this.m_RecordCount = value;
            }
            get
            {
                return this.m_RecordCount;
            }
        }

        /// <summary>
        /// 当前的页面索引, 开始为1
        /// </summary>
        [Description("当前的页面索引, 开始为1"), DefaultValue(0), Category("分页")]
        [Browsable(false)]
        public int CurrentPageIndex
        {
            set
            {
                this.m_CurrentPageIndex = value;
            }
            get
            {
                return this.m_CurrentPageIndex;
            }
        }

        /// <summary>
        /// 初始化分页信息
        /// </summary>
        /// <param name="info"></param>
        public void InitPageInfo(PagerInfo info)
        {
            this.m_RecordCount = info.RecordCount;
            this.m_PageSize = info.PageSize;
            this.InitPageInfo();
        }

        /// <summary> 
        /// 初始化分页信息
        /// <param name="pageSize">每页记录数</param>
        /// <param name="recordCount">总记录数</param>
        /// </summary>
        public void InitPageInfo(int recordCount, int pageSize)
        {
            this.m_RecordCount = recordCount;
            this.m_PageSize = pageSize;
            this.InitPageInfo();
        }

        /// <summary> 
        /// 初始化分页信息
        /// <param name="recordCount">总记录数</param>
        /// </summary>
        public void InitPageInfo(int recordCount)
        {
            this.m_RecordCount = recordCount;
            this.InitPageInfo();
        }

        /// <summary> 
        /// 初始化分页信息
        /// </summary>
        public void InitPageInfo()
        {
            if (this.m_PageSize < 1)
                this.m_PageSize = 10; //如果每页记录数不正确，即更改为10
            if (this.m_RecordCount < 0)
                this.m_RecordCount = 0; //如果记录总数不正确，即更改为0

            //取得总页数
            if (this.m_RecordCount % this.m_PageSize == 0)
            {
                this.m_PageCount = this.m_RecordCount / this.m_PageSize;
            }
            else
            {
                this.m_PageCount = this.m_RecordCount / this.m_PageSize + 1;
            }

            //设置当前页
            if (this.m_CurrentPageIndex > this.m_PageCount)
            {
                this.m_CurrentPageIndex = this.m_PageCount;
            }
            if (this.m_CurrentPageIndex < 1)
            {
                this.m_CurrentPageIndex = 1;
            }

            //设置按钮的可用性
            bool enable = (this.CurrentPageIndex > 1);
            this.btn_Previous.Enabled = enable;

            enable = (this.CurrentPageIndex < this.PageCount);
            this.btn_Next.Enabled = enable;

            this.txt_CurrentPage.Text = this.m_CurrentPageIndex.ToString();
            this.label_PageInfo.Text = string.Format("共 {0} 条记录，每页 {1} 条，共 {2} 页", this.m_RecordCount, this.m_PageSize, this.m_PageCount);

            this.btn_Export.Enabled = this.ShowExportButton;
            this.btn_ExportCurrent.Enabled = this.ShowExportButton;
        }

        /// <summary>
        /// 刷新页面数据
        /// </summary>
        /// <param name="page">页码</param>
        public void RefreshData(int page)
        {
            this.m_CurrentPageIndex = page;
            EventArgs e = new EventArgs();
            OnPageChanged(e);
        }


        private void btn_First_Click(object sender, EventArgs e)
        {
            this.RefreshData(1);
        }

        private void btn_Previous_Click(object sender, EventArgs e)
        {
            if (this.m_CurrentPageIndex > 1)
            {
                this.RefreshData(this.m_CurrentPageIndex - 1);
            }
            else
            {
                this.RefreshData(1);
            }
        }

        private void btn_Next_Click(object sender, EventArgs e)
        {
            if (this.m_CurrentPageIndex < this.m_PageCount)
            {
                this.RefreshData(this.m_CurrentPageIndex + 1);
            }
            else if (this.m_PageCount < 1)
            {
                this.RefreshData(1);
            }
            else
            {
                this.RefreshData(this.m_PageCount);
            }
        }

        private void btn_Last_Click(object sender, EventArgs e)
        {
            if (this.m_PageCount > 0)
            {
                this.RefreshData(this.m_PageCount);
            }
            else
            {
                this.RefreshData(1);
            }
        }

        private void txt_CurrentPage_KeyDown(object sender, KeyEventArgs e)
        {
            if (e.KeyCode == Keys.Enter)
            {
                int num;
                try
                {
                    num = Convert.ToInt16(this.txt_CurrentPage.Text);
                }
                catch 
                {
                    num = 1;
                }

                if (num > this.m_PageCount)
                    num = this.m_PageCount;
                if (num < 1)
                    num = 1;

                this.RefreshData(num);
            }
        }

        private void btn_ExportCurrent_Click(object sender, EventArgs e)
        {
            if (ExportCurrent != null)
            {
                ExportCurrent(sender, e);
            }
        }

        private void btn_Export_Click(object sender, EventArgs e)
        {
            if (ExportAll != null)
            {
                ExportAll(sender, e);
            }
        }
    }
}