using NPOI.HSSF.UserModel;
using NPOI.SS.UserModel;
using System;
using System.Data;
using System.IO;
using System.Web;

namespace WX.CRM.Common
{
    public class ExcelHandler
    {
        /// <summary>
        /// 由DataSet导出Excel
        /// </summary>
        /// <param name="sourceDs"></param>
        /// <param name="fileName">指定Excel工作表名称</param>
        /// <param name="sheetName"></param>
        /// <returns>Excel工作表</returns>
        public static void ExportDataSetToExcel(DataSet sourceDs, string fileName, string sheetName)
        {

            MemoryStream ms = ExportDataSetToExcel(sourceDs, sheetName) as MemoryStream;
            HttpContext.Current.Response.AppendHeader("Content-Disposition", "attachment;filename=" + fileName);
            HttpContext.Current.Response.BinaryWrite(ms.ToArray());
            HttpContext.Current.Response.End();
            ms.Close();
            ms = null;
        }
        /// <summary>
        /// 由DataSet导出Excel
        /// </summary>
        /// <param name="sourceDs">数据源</param>
        /// <param name="folderPath">文件夹名</param>
        /// <param name="fileName">文件名</param>
        /// <param name="sheetName">指定Excel工作表名称</param>
        public static void SaveDataSetToExcel(DataSet sourceDs, string folderPath, string fileName, string sheetName)
        {
            Stream stream = ExportDataSetToExcel(sourceDs, sheetName);
            FileUnit.WriteWithDirectory(folderPath, fileName, stream);
        }
        /// <summary>
        /// 由DataSet导出Excel
        /// </summary>
        /// <param name="sourceTable">要导出数据的DataTable</param>
        /// <param name="sheetName">工作表名称</param>
        /// <returns>Excel工作表</returns>
        private static Stream ExportDataSetToExcel(DataSet sourceDs, string sheetName)
        {
            HSSFWorkbook workbook = new HSSFWorkbook();
            MemoryStream ms = new MemoryStream();
            string[] sheetNames = sheetName.Split(',');
            int sheetSize = 65530;
            int rowCount = sourceDs.Tables[0].Rows.Count;
            int sheetCout = (rowCount / sheetSize) + 1;
            for (int i = 0; i < sheetNames.Length; i++)
            {
                for (int j = 0; j < sheetCout; j++)
                {
                    ISheet sheet = workbook.CreateSheet(sheetNames[i] + j);
                    IRow headerRow = sheet.CreateRow(0);
                    // handling header.
                    foreach (DataColumn column in sourceDs.Tables[i].Columns)
                        headerRow.CreateCell(column.Ordinal).SetCellValue(column.ColumnName);
                    // handling value.
                    int rowIndex = 1;
                    int mcount = (j + 1) * sheetSize > rowCount ? rowCount : (j + 1) * sheetSize;
                    for (int m = (j * sheetSize); m < mcount; m++)
                    {
                        DataRow row = sourceDs.Tables[i].Rows[m];
                        IRow dataRow = sheet.CreateRow(rowIndex);
                        foreach (DataColumn column in sourceDs.Tables[i].Columns)
                        {
                            ICell icell = dataRow.CreateCell(column.Ordinal);
                            ICellValeSet(column.DataType.FullName, row[column].ToString(), icell);
                            //dataRow.CreateCell(column.Ordinal).SetCellValue(row[column].ToString());
                        }
                        rowIndex++;
                    }
                }
            }
            workbook.Write(ms);
            ms.Flush();
            ms.Position = 0;
            workbook = null;
            return ms;
        }
        private static void ICellValeSet(string dbType, string dbValue, ICell icell)
        {
            switch (GetCellType(dbType))
            {
                case stylexls.数字:
                    int wovalue = 0;
                    if (int.TryParse(dbValue, out wovalue))
                    {
                        icell.SetCellValue(wovalue);
                    }
                    else
                    {
                        icell.SetCellValue(dbValue);
                    }
                    break;
                case stylexls.小数:
                    double dobValue = 0;
                    if (double.TryParse(dbValue, out dobValue))
                    {
                        icell.SetCellValue(dobValue);
                    }
                    else
                    {
                        icell.SetCellValue(dbValue);
                    }
                    break;
                case stylexls.时间:
                    DateTime timeValue;
                    if (DateTime.TryParse(dbValue, out timeValue))
                    {
                        icell.SetCellValue(timeValue.ToString("yyyy/MM/dd HH:mm:ss"));
                    }
                    else
                    {
                        icell.SetCellValue("");
                    }
                    break;
                case stylexls.默认: icell.SetCellValue(dbValue.ToString()); break;
            }
        }
        private static void ICellValeSet(ExcelCell cell, ICell icell)
        {
            switch (GetCellType(cell.type))
            {
                case stylexls.数字:
                    int wovalue = 0;
                    if (int.TryParse(cell.nvalue, out wovalue))
                    {
                        icell.SetCellValue(wovalue);
                    }
                    else
                    {
                        icell.SetCellValue(cell.nvalue);
                    }
                    break;
                case stylexls.小数:
                    double dobValue = 0;
                    if (double.TryParse(cell.nvalue, out dobValue))
                    {
                        icell.SetCellValue(dobValue);
                    }
                    else
                    {
                        icell.SetCellValue(cell.nvalue);
                    }
                    break;
                case stylexls.时间:
                    DateTime timeValue;
                    if (DateTime.TryParse(cell.nvalue, out timeValue))
                    {
                        icell.SetCellValue(timeValue.ToString("yyyy/MM/dd HH:mm:ss"));
                    }
                    else
                    {
                        icell.SetCellValue("");
                    }
                    break;
                case stylexls.默认: icell.SetCellValue(cell.nvalue.ToString()); break;
            }
        }
        private static stylexls GetCellType(string fullTypeName)
        {
            if (fullTypeName == null)
                return stylexls.默认;
            if (fullTypeName.IndexOf("System.Decimal") > -1)
                return stylexls.小数;
            if (fullTypeName.IndexOf("System.Int") > -1)
                return stylexls.数字;
            if (fullTypeName.IndexOf("System.DateTime") > -1)
                return stylexls.时间;
            return stylexls.默认;
        }
    }
    #region 定义单元格常用到样式的枚举
    public enum stylexls
    {
        头,
        url,
        时间,
        数字,
        小数,
        钱,
        百分比,
        中文大写,
        科学计数法,
        默认
    }
    #endregion
    public class ExcelCell
    {
        /// <summary>
        /// 英文字段名称
        /// </summary>
        public string fild { get; set; }
        /// <summary>
        /// 字段的数据类型
        /// </summary>
        public string type { get; set; }
        /// <summary>
        /// 字段的中文标题
        /// </summary>
        public string title { get; set; }
        /// <summary>
        /// 字段的值
        /// </summary>
        public string nvalue { get; set; }

    }
}