using NPOI.HSSF.UserModel;
using NPOI.HSSF.Util;
using NPOI.SS.UserModel;
using NPOI.SS.Util;
using NPOI.XSSF.UserModel;

using System;
using System.Collections.Generic;
using System.Data;
using System.IO;
using System.Linq;
using System.Reflection;
using System.Web.Hosting;

namespace Epost.Common
{
    public class ExcelHelper
    {





        #region 导出


        /// <summary>
        /// 
        /// </summary>
        /// <param name="resultMsg">导出结果</param>
        /// <param name="excelFilePath">保存excel文件路径</param>
        /// <param name="table"></param>
        /// <param name="filename"></param>
        /// <param name="filetitle"></param>
        /// <param name="WebRootPath"></param>
        /// <returns></returns>

        public bool ExcelDataExport(DataTable table, string filename, string filetitle, string WebRootPath, out string resultMsg, out string excelFilePath)
        {
            var result = true;
            excelFilePath = "";
            resultMsg = "successfully";
            //Excel导出名称

            try
            {
                //首先创建Excel文件对象
                var workbook = new HSSFWorkbook();

                //创建工作表，也就是Excel中的sheet，给工作表赋一个名称(Excel底部名称)
                var sheet = workbook.CreateSheet(filename);

                //sheet.DefaultColumnWidth = 20;//默认列宽

                sheet.ForceFormulaRecalculation = true;//TODO:是否开始Excel导出后公式仍然有效（非必须）


                //设置顶部大标题样式
                var cellStyleFont = CreateStyle(workbook, HorizontalAlignment.Center, VerticalAlignment.Center, 20, true, 700, "楷体", true, false, false, true, FillPattern.SolidForeground, HSSFColor.White.Index, HSSFColor.Black.Index,
                    FontUnderlineType.None, FontSuperScript.None, false);

                //第一行表单
                IRow row = CreateRow(sheet, 0, 28);

                var cell = row.CreateCell(0);
                sheet.AddMergedRegion(new CellRangeAddress(0, 0, 0, table.Columns.Count - 1));
                cell.SetCellValue(filetitle);//合并单元格后，只需对第一个位置赋值即可（TODO:顶部标题）
                cell.CellStyle = cellStyleFont;
                //处理表格列头
                row = sheet.CreateRow(1);
                for (int i = 0; i < table.Columns.Count; i++)
                {
                    row.CreateCell(i).SetCellValue(table.Columns[i].ColumnName);
                    row.Height = 350;
                    sheet.AutoSizeColumn(i);
                }

                //处理数据内容
                for (int i = 0; i < table.Rows.Count; i++)
                {
                    row = sheet.CreateRow(2 + i);
                    row.Height = 250;
                    for (int j = 0; j < table.Columns.Count; j++)
                    {
                        row.CreateCell(j).SetCellValue(table.Rows[i][j].ToString());
                        sheet.SetColumnWidth(j, 256 * 15);
                    }
                }

                string folder = DateTime.Now.ToString("yyyyMMdd");


                //保存文件到静态资源文件夹中（wwwroot）,使用绝对路径
                var uploadPath = WebRootPath + "/File/" + folder + "/";

                //excel保存文件名
                string excelFileName = filename + "_" + DateTime.Now.ToString("yyyyMMddHHmmss") + ".xls";

                //创建目录文件夹
                if (!Directory.Exists(uploadPath))
                {
                    Directory.CreateDirectory(uploadPath);
                }

                //Excel的路径及名称
                string excelPath = uploadPath + excelFileName;

                //使用FileStream文件流来写入数据（传入参数为：文件所在路径，对文件的操作方式，对文件内数据的操作）
                var fileStream = new FileStream(excelPath, FileMode.OpenOrCreate, FileAccess.ReadWrite);

                //向Excel文件对象写入文件流，生成Excel文件
                workbook.Write(fileStream);

                //关闭文件流
                fileStream.Close();

                //释放流所占用的资源
                fileStream.Dispose();

                //excel文件保存的相对路径，提供前端下载
                var relativePositioning = "/File/" + folder + "/" + excelFileName;

                excelFilePath = relativePositioning;
            }
            catch (Exception e)
            {
                result = false;
                resultMsg = e.Message;
            }
            return result;
        }



        /// <summary>
        /// 行内单元格常用样式设置
        /// </summary>
        /// <param name="workbook">Excel文件对象</param>
        /// <param name="hAlignment">水平布局方式</param>
        /// <param name="vAlignment">垂直布局方式</param>
        /// <param name="fontHeightInPoints">字体大小</param>
        /// <param name="isAddBorder">是否需要边框</param>
        /// <param name="boldWeight">字体加粗 (None = 0,Normal = 400，Bold = 700</param>
        /// <param name="fontName">字体（仿宋，楷体，宋体，微软雅黑...与Excel主题字体相对应）</param>
        /// <param name="isAddBorderColor">是否增加边框颜色</param>
        /// <param name="isItalic">是否将文字变为斜体</param>
        /// <param name="isLineFeed">是否自动换行</param>
        /// <param name="isAddCellBackground">是否增加单元格背景颜色</param>
        /// <param name="fillPattern">填充图案样式(FineDots 细点，SolidForeground立体前景，isAddFillPattern=true时存在)</param>
        /// <param name="cellBackgroundColor">单元格背景颜色（当isAddCellBackground=true时存在）</param>
        /// <param name="fontColor">字体颜色</param>
        /// <param name="underlineStyle">下划线样式（无下划线[None],单下划线[Single],双下划线[Double],会计用单下划线[SingleAccounting],会计用双下划线[DoubleAccounting]）</param>
        /// <param name="typeOffset">字体上标下标(普通默认值[None],上标[Sub],下标[Super]),即字体在单元格内的上下偏移量</param>
        /// <param name="isStrikeout">是否显示删除线</param>
        /// <returns></returns>
        public HSSFCellStyle CreateStyle(HSSFWorkbook workbook, HorizontalAlignment hAlignment, VerticalAlignment vAlignment, short fontHeightInPoints, bool isAddBorder, short boldWeight, string fontName = "宋体", bool isAddBorderColor = true, bool isItalic = false, bool isLineFeed = false, bool isAddCellBackground = false, FillPattern fillPattern = FillPattern.NoFill, short cellBackgroundColor = HSSFColor.Yellow.Index, short fontColor = HSSFColor.Black.Index, FontUnderlineType underlineStyle =
            FontUnderlineType.None, FontSuperScript typeOffset = FontSuperScript.None, bool isStrikeout = false)
        {
            HSSFCellStyle cellStyle = (HSSFCellStyle)workbook.CreateCellStyle(); //创建列头单元格实例样式
            cellStyle.Alignment = hAlignment; //水平居中
            cellStyle.VerticalAlignment = vAlignment; //垂直居中
            cellStyle.WrapText = isLineFeed;//自动换行



            //背景颜色，边框颜色，字体颜色都是使用 HSSFColor属性中的对应调色板索引，关于 HSSFColor 颜色索引对照表，详情参考：https://www.cnblogs.com/Brainpan/p/5804167.html

            //TODO：引用了NPOI后可通过ICellStyle 接口的 FillForegroundColor 属性实现 Excel 单元格的背景色设置，FillPattern 为单元格背景色的填充样式

            //TODO:十分注意，要设置单元格背景色必须是FillForegroundColor和FillPattern两个属性同时设置，否则是不会显示背景颜色
            if (isAddCellBackground)
            {
                cellStyle.FillForegroundColor = cellBackgroundColor;//单元格背景颜色
                cellStyle.FillPattern = fillPattern;//填充图案样式(FineDots 细点，SolidForeground立体前景)
            }


            //是否增加边框
            if (isAddBorder)
            {
                //常用的边框样式 None(没有),Thin(细边框，瘦的),Medium(中等),Dashed(虚线),Dotted(星罗棋布的),Thick(厚的),Double(双倍),Hair(头发)[上右下左顺序设置]
                cellStyle.BorderBottom = BorderStyle.Thin;
                cellStyle.BorderRight = BorderStyle.Thin;
                cellStyle.BorderTop = BorderStyle.Thin;
                cellStyle.BorderLeft = BorderStyle.Thin;
            }

            //是否设置边框颜色
            if (isAddBorderColor)
            {
                //边框颜色[上右下左顺序设置]
                cellStyle.TopBorderColor = HSSFColor.DarkGreen.Index;//DarkGreen(黑绿色)
                cellStyle.RightBorderColor = HSSFColor.DarkGreen.Index;
                cellStyle.BottomBorderColor = HSSFColor.DarkGreen.Index;
                cellStyle.LeftBorderColor = HSSFColor.DarkGreen.Index;
            }

            /**
             * 设置相关字体样式
             */
            var cellStyleFont = (HSSFFont)workbook.CreateFont(); //创建字体

            //假如字体大小只需要是粗体的话直接使用下面该属性即可
            //cellStyleFont.IsBold = true;

            cellStyleFont.Boldweight = boldWeight; //字体加粗
            cellStyleFont.FontHeightInPoints = fontHeightInPoints; //字体大小
            cellStyleFont.FontName = fontName;//字体（仿宋，楷体，宋体 ）
            cellStyleFont.Color = fontColor;//设置字体颜色
            cellStyleFont.IsItalic = isItalic;//是否将文字变为斜体
            cellStyleFont.Underline = underlineStyle;//字体下划线
            cellStyleFont.TypeOffset = typeOffset;//字体上标下标
            cellStyleFont.IsStrikeout = isStrikeout;//是否有删除线

            cellStyle.SetFont(cellStyleFont); //将字体绑定到样式
            return cellStyle;
        }


        /// <summary>
        /// TODO:先创建行，然后在创建对应的列
        /// 创建Excel中指定的行
        /// </summary>
        /// <param name="sheet">Excel工作表对象</param>
        /// <param name="rowNum">创建第几行(从0开始)</param>
        /// <param name="rowHeight">行高</param>
        public HSSFRow CreateRow(ISheet sheet, int rowNum, float rowHeight)
        {
            HSSFRow row = (HSSFRow)sheet.CreateRow(rowNum); //创建行
            row.HeightInPoints = rowHeight; //设置列头行高
            return row;
        }

        /// <summary>
        /// 创建行内指定的单元格
        /// </summary>
        /// <param name="row">需要创建单元格的行</param>
        /// <param name="cellStyle">单元格样式</param>
        /// <param name="cellNum">创建第几个单元格(从0开始)</param>
        /// <param name="cellValue">给单元格赋值</param>
        /// <returns></returns>
        public HSSFCell CreateCells(HSSFRow row, HSSFCellStyle cellStyle, int cellNum, string cellValue)
        {
            HSSFCell cell = (HSSFCell)row.CreateCell(cellNum); //创建单元格
            cell.CellStyle = cellStyle; //将样式绑定到单元格
            if (!string.IsNullOrWhiteSpace(cellValue))
            {
                //单元格赋值
                cell.SetCellValue(cellValue);
            }

            return cell;
        }
        #endregion

        #region 导入


        /// <summary>
        /// 读取excel表格中的数据,将Excel文件流转化为dataTable数据源  
        /// 默认第一行为标题 
        /// </summary>
        /// <param name="stream">excel文档文件流</param>
        /// <param name="fileType">文档格式</param>
        /// <param name="isSuccess">是否转化成功</param>
        /// <param name="resultMsg">转换结果消息</param>
        /// <returns></returns>
        public DataTable ExcelToDataTable(Stream stream, string fileType)
        {
            //isSuccess = false;
            //resultMsg = "Excel文件流成功转化为DataTable数据源";
            var excelToDataTable = new DataTable();

            try
            {
                IWorkbook workbook;

                //XSSFWorkbook 适用XLSX格式，HSSFWorkbook 适用XLS格式
                #region 判断excel版本
                switch (fileType)
                {
                    //2007以下版本excel
                    case ".xlsx":
                        workbook = new XSSFWorkbook(stream);
                        break;
                    case ".xls":
                        workbook = new HSSFWorkbook(stream);
                        break;
                    default:
                        throw new Exception("Excel文档格式有误");
                }
                #endregion

                var sheet = workbook.GetSheetAt(0);
                var rows = sheet.GetRowEnumerator();

                var headerRow = sheet.GetRow(0);
                int cellCount = headerRow.LastCellNum;//最后一行列数（即为总列数）

                //获取第一行标题列数据源,转换为dataTable数据源的表格标题名称
                for (var j = 0; j < cellCount; j++)
                {
                    var cell = headerRow.GetCell(j);
                    excelToDataTable.Columns.Add(cell.ToString());
                }

                //获取Excel表格中除标题以为的所有数据源，转化为dataTable中的表格数据源
                for (var i = (sheet.FirstRowNum + 1); i <= sheet.LastRowNum; i++)
                {
                    var dataRow = excelToDataTable.NewRow();

                    var row = sheet.GetRow(i);

                    if (row == null) continue; //没有数据的行默认是null　

                    for (int j = row.FirstCellNum; j < cellCount; j++)
                    {
                        if (row.GetCell(j) != null)//单元格内容非空验证
                        {
                            //获取指定的单元格信息
                            var cell = row.GetCell(j);

                            #region NPOI获取Excel单元格数据不同类型数据
                            switch (cell.CellType)
                            {
                                //首先在NPOI中数字和日期都属于Numeric类型
                                //通过NPOI中自带的DateUtil.IsCellDateFormatted判断是否为时间日期类型
                                //case CellType.Numeric when DateUtil.IsCellDateFormatted(cell):
                                //    dataRow[j] = cell.DateCellValue;
                                //    break;
                                case CellType.Numeric:
                                    //其他数字类型
                                    dataRow[j] = cell.NumericCellValue;
                                    break;
                                //空数据类型
                                case CellType.Blank:
                                    dataRow[j] = "";
                                    break;
                                //公式类型
                                case CellType.Formula:
                                    {
                                        HSSFFormulaEvaluator eva = new HSSFFormulaEvaluator(workbook);
                                        dataRow[j] = eva.Evaluate(cell).StringValue;
                                        break;
                                    }
                                //布尔类型
                                case CellType.Boolean:
                                    dataRow[j] = row.GetCell(j).BooleanCellValue;
                                    break;
                                //错误
                                case CellType.Error:
                                    // dataRow[j] = HSSFErrorConstants.GetText(row.GetCell(j).ErrorCellValue);
                                    break;
                                //其他类型都按字符串类型来处理（未知类型CellType.Unknown，字符串类型CellType.String）
                                default:
                                    dataRow[j] = cell.StringCellValue;
                                    break;
                            }
                            #endregion
                        }
                    }
                    excelToDataTable.Rows.Add(dataRow);
                }

                //isSuccess = true;
            }
            catch (Exception e)
            {
                LogHelper.WriteLogInfo("上传" + e, LogHelper.Log_Type.ERROR);
            }

            return excelToDataTable;
        }
        #endregion
    }
}