using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Diagnostics;
using System.Drawing;
using System.IO;
using System.Windows.Forms;
using OfficeOpenXml;
using OfficeOpenXml.Style;
using CK.SCP.Utils;

namespace ChangkeTec.Utils
{
    public class EpPlusHelper
    {
        private DataSet _dsExcel;
        private DataTable _dtExcel;
        private string _excelFileName;
        private List<string> _readSheetNames;
        private BackgroundWorker _bgw;
        private string _pasword = string.Empty;
        public Action<DataTable> ReadCompleted;
        readonly SaveFileDialog _sfd = new SaveFileDialog
        {
            Filter = "Excel 工作簿 (*.xlsx)|*.xlsx",
            CheckFileExists = false,
            CheckPathExists = false,
            FilterIndex = 0,
            RestoreDirectory = true,
            CreatePrompt = false,
            Title = "保存为Excel文件"
        };
        public EpPlusHelper()
        {
            _bgw = new BackgroundWorker { WorkerReportsProgress = true, WorkerSupportsCancellation = true };
        }

        #region Read

        public void ReadExcelToDt(string fileName, string password = "")
        {
            _excelFileName = fileName;
            _pasword = password;
            var excelFileExt = GetFileExt(fileName);

            switch (excelFileExt)
            {
                case ".XLSX":
                    var poDv = new ProcessOperator { BackgroundWork = ReadExcelToDataTable };
                    poDv.BackgroundWorkerCompleted += ReadExcel_Completed;
                    poDv.Start();
                    break;
                case ".XLS":
                    throw new Exception($"需要使用NPOI解析后缀名为{excelFileExt}的文件！");
                default:
                    throw new Exception($"无法解析后缀名为{excelFileExt}的文件！");
            }

            //return _dtExcel;
        }

        private DataTable ReadData(ExcelWorksheet sheet)
        {
            var dt = new DataTable(sheet.Name);
            int colStart = sheet.Dimension.Start.Column;
            int colEnd = sheet.Dimension.End.Column;
            int rowStart = sheet.Dimension.Start.Row;
            int rowEnd = sheet.Dimension.End.Row;

            for (var i = colStart; i < colEnd + 1; i++)//从1开始计数
            {
                var columnName = sheet.Cells[rowStart, i].Value?.ToString();
                dt.Columns.Add(columnName);
            }


            for (var row = rowStart + 1; row < rowEnd + 1; row++)//从1开始计数，跳过第一行
            {
                var dr = dt.NewRow();
                for (var col = colStart; col < colEnd + 1; col++)//从1开始计数
                {
                    dr[col - 1] = sheet.Cells[row, col]?.Value?.ToString();
                }
                dt.Rows.Add(dr);
            }
            RemoveEmptyRow(dt);
            return dt;
        }

        private void ReadExcelToDataTable()
        {

            _readSheetNames = new List<string>();
            _dsExcel = new DataSet();
            var fs = new FileStream(_excelFileName, FileMode.Open);
            try
            {

                using (
                    var package = string.IsNullOrEmpty(_pasword)
                    ? new ExcelPackage(fs)
                    : new ExcelPackage(fs, _pasword)
                )
                {
                    var validSheetList = GetValidSheetList(package);
                    if (validSheetList.Count == 0) throw new Exception("未找到有效的Excel表单");
                    var sheet = validSheetList[0];
                    _readSheetNames.Add(sheet.Name);
                    _dtExcel = ReadData(sheet);
                }
            }
            finally
            {
                fs.Close();
                fs.Dispose();
            }
        }


        private void ReadExcel_Completed(object sender, BackgroundWorkerEventArgs e)
        {
            if (e.BackGroundException == null)
            {
                if (_readSheetNames == null || _readSheetNames.Count == 0)
                {
                    throw new Exception("文件读失败，未找到符合的系统要求的工作表！");
                }
                else if (ReadCompleted != null)
                {
                    ReadCompleted(_dtExcel);
                }
            }
            else
            {
                throw new Exception("文件读取失败,请联系管理员！");
            }
        }

        private List<ExcelWorksheet> GetValidSheetList(ExcelPackage package)
        {
            var list = new List<ExcelWorksheet>();
            for (var i = 1; i <= package.Workbook.Worksheets.Count; i++)
            {
                var sheet = package.Workbook.Worksheets[i];
                var tableName = sheet.Name;

                if (!tableName.Equals("_xlnm#_FilterDatabase") &&
                    tableName.IndexOf("_", StringComparison.Ordinal) != tableName.Length - 1 &&
                    tableName.IndexOf("FilterDatabase", StringComparison.Ordinal) == -1)
                {
                    list.Add(sheet);
                }
            }
            return list;
        }

        private void GetFileName(string fileName)
        {
            _excelFileName = fileName;
        }

        private string GetFileExt(string fileName)
        {
            return Path.GetExtension(fileName)?.ToUpper();
        }

        #endregion

        #region Write

        public void WriteDsToExcel(DataSet ds, string password = "")
        {
            if (_sfd.ShowDialog() != DialogResult.OK) return;
            var fileName = _sfd.FileName;
            WriteDsToExcel(ds, fileName, password);
        }

        public void WriteDsToExcel(DataSet ds, string excelFileName, string password)
        {
            if (ds == null || ds.Tables.Count == 0)
                throw new Exception("当前表单没有任何数据");
            var poDv = new ProcessOperator
            {
                BackgroundWork = () => WriteDataSetToExcel(ds, excelFileName, password)
            };
            poDv.BackgroundWorkerCompleted += WriteExcel_Completed;
            poDv.Start();
        }

        private void WriteDataSetToExcel(DataSet ds, string excelFileName, string password)
        {
            var newFile = GetNewFile(excelFileName);
            _excelFileName = excelFileName;

            using (var package = string.IsNullOrEmpty(password) ? new ExcelPackage(newFile) : new ExcelPackage(newFile, password))
            {
                foreach (DataTable dt in ds.Tables)
                {
                    if (string.IsNullOrEmpty(dt?.TableName) || dt.Rows.Count == 0) continue;
                    EpPlusHelper.RemoveEmptyRow(dt);
                    var sheetName = "sheet1";
                    if (!string.IsNullOrEmpty(dt.TableName))
                        sheetName = dt.TableName;
                    var worksheet = package.Workbook.Worksheets.Add(sheetName);
                    //表头  
                    SetTitle(dt, worksheet);
                    //各行数据  
                    SetData(dt, worksheet);
                    //设置单元格格式  
                    SetFormat(worksheet);
                }
                if (package.Workbook.Worksheets.Count <= 0) return;
                if (string.IsNullOrEmpty(password))
                    package.Save();
                else
                    package.Save(password);
            }
        }

        public void WriteDtToExcel(DataTable dt, string password = "")
        {

            if (_sfd.ShowDialog() != DialogResult.OK) return;
            var fileName = _sfd.FileName;
            WriteDtToExcel(dt, fileName, password);
        }

        public void WriteDtToExcel(DataTable dt, string excelFileName, string password)
        {
            var excelFileExt = GetFileExt(excelFileName);
            switch (excelFileExt)
            {
                case ".XLSX":

                    if (dt == null || dt.Rows.Count <= 0) throw new Exception("当前表单没有任何数据");
                    var poDv = new ProcessOperator { BackgroundWork = () => WriteDataTableToExcel(dt, excelFileName, password) };
                    poDv.BackgroundWorkerCompleted += WriteExcel_Completed;
                    poDv.Start();
                    break;
                case ".XLS":
                    throw new Exception($"需要使用NPOI解析后缀名为{excelFileExt}的文件！");
                default:
                    throw new Exception($"无法解析后缀名为{excelFileExt}的文件！");
            }
        }

        private static FileInfo GetNewFile(string excelFileName)
        {
            var newFile = new FileInfo(excelFileName);
            if (newFile.Exists)
            {
                newFile.Delete(); // ensures we create a new workbook  
                newFile = new FileInfo(excelFileName);
            }
            return newFile;
        }

        private void WriteDataTableToExcel(DataTable dt, string excelFileName, string password)
        {
            var newFile = GetNewFile(excelFileName);

            _excelFileName = excelFileName;

            using (var package = string.IsNullOrEmpty(password) ? new ExcelPackage(newFile) : new ExcelPackage(newFile, password))
            {
                var sheetName = "sheet1";
                if (!string.IsNullOrEmpty(dt.TableName))
                    sheetName = dt.TableName;
                using (var worksheet = package.Workbook.Worksheets.Add(sheetName))
                {
                    //表头  
                    SetTitle(dt, worksheet);
                    //各行数据  
                    SetData(dt, worksheet);
                    //设置单元格格式  
                    SetFormat(worksheet);
                    if (string.IsNullOrEmpty(password))
                        package.Save();
                    else
                        package.Save(password);
                }
            }
        }

        private void WriteExcel_Completed(object sender, BackgroundWorkerEventArgs e)
        {
            var newFile = new FileInfo(_excelFileName);
            if (newFile.Exists)
                Process.Start(_excelFileName);
        }

        private static void SetFormat(ExcelWorksheet worksheet)
        {
            if (worksheet.Dimension == null) return;
            int colStart = worksheet.Dimension.Start.Column;
            int colEnd = worksheet.Dimension.End.Column;
            int rowStart = worksheet.Dimension.Start.Row;
            int rowEnd = worksheet.Dimension.End.Row;

            //            using (var range = worksheet.Cells[1, 1, 1, dt.Columns.Count])
            using (var range = worksheet.Cells[rowStart, colStart, rowStart, colEnd])
            {
                range.Style.Fill.PatternType = ExcelFillStyle.LightGrid;
                range.Style.Fill.BackgroundColor.SetColor(Color.LightYellow);
                range.Style.HorizontalAlignment = ExcelHorizontalAlignment.CenterContinuous;
            }
            //            using (var range = worksheet.Cells[1, 1, dt.Rows.Count + 1, dt.Columns.Count])
            using (var range = worksheet.Cells[rowStart, colStart, rowEnd, colEnd])
            {
                range.Style.Border.BorderAround(ExcelBorderStyle.Thin);
                range.Style.Font.Name = "微软雅黑";
                range.Style.Font.Size = 12;
                range.AutoFitColumns();
            }
        }

        private static void SetData(DataTable dt, ExcelWorksheet worksheet)
        {
            for (int i = 0; i < dt.Rows.Count; i++)
            {
                var row = i + 2;
                for (int j = 0; j < dt.Columns.Count; j++)
                {
                    var col = j + 1;
                    var s = dt.Rows[i][j];
                    //////////////////
                    //格式化日期字段
                    var dc = dt.Columns[j];
                    if (dc.DataType.FullName == "System.DateTime")
                    {
                        DateTime time;
                        DateTime.TryParse(s.ToString(), out time);
                        s = time.ToString("yyyy-MM-dd HH:mm:ss");
                    }
                    //使用EPPLUS貌似不需要做这个转换了？
                    //                        if (dc.DataType.FullName == "System.String")
                    //                        {
                    //                            s = "'" + s;
                    //                        }
                    decimal d;
                    if (decimal.TryParse(s.ToString(), out d))
                    {
                        if (Math.Round(d, 5) == 0)
                        {
                            s = 0;
                        }
                    }
                    worksheet.Cells[row, col].Value = s;
                }
            }
        }

        private static void SetTitle(DataTable dt, ExcelWorksheet worksheet)
        {
            int row = 1;
            for (int i = 0; i < dt.Columns.Count; i++)
            {
                var dc = dt.Columns[i];
                row = 1;
                var col = i + 1;
                worksheet.Cells[row, col].Value = dc.ColumnName;
            }
            worksheet.View.FreezePanes(row + 1, 1); //冻结表头  
        }

        #endregion

        public static void RemoveEmptyRow(DataTable dt)
        {
            if (dt == null || dt.Rows.Count == 0)
                return;
            var isEmpty = true;
            for (var idx = dt.Rows.Count - 1; idx >= 0; idx--)
            {
                var dr = dt.Rows[idx];
                for (var i = 0; i < dt.Columns.Count; i++)
                {
                    if (dr[i].ToString().Trim() != string.Empty)
                    {
                        isEmpty = false;
                    }
                }
                if (isEmpty)
                    dt.Rows.Remove(dr);
            }
        }
    }

}