using NPOI.HSSF.UserModel;
using NPOI.SS.UserModel;
using NPOI.XSSF.UserModel;
using System;
using System.Collections.Generic;
using System.IO;
using System.Text;

namespace Shentun.Utilities
{
    public class NPOIExcelHelper : IDisposable
    {
        private IWorkbook _workbook;
        private ISheet _sheet;
        private bool _disposed;
        private FileStream _fileStream = null;
        public void CreateWorkbook()
        {
            if (_workbook != null)
            {
                throw new Exception("已存在一个工作簿，禁止创建");
            }
            _workbook = new HSSFWorkbook();
        }
        public void OpenWorkbook(string fileName)
        {
            if (_workbook != null)
            {
                throw new Exception("已存在一个工作簿，禁止打开");
            }
            if (!File.Exists(fileName))
            {
                throw new Exception(fileName + "不存在，不能打开");
            }
            _fileStream = new FileStream(fileName, FileMode.Open, FileAccess.ReadWrite);
            if (fileName.IndexOf(".xlsx") > 0) // 2007版本
                _workbook = new XSSFWorkbook(_fileStream);
            else if (fileName.IndexOf(".xls") > 0) // 2003版本
                _workbook = new HSSFWorkbook(_fileStream);
            else
                throw new Exception("Excel文件后缀名必须为xls或xlsx");



        }
        public void SelectSheet(string sheetName)
        {
            _sheet = _workbook.GetSheet(sheetName);
            if (_sheet == null)
                throw new Exception(sheetName + "不存在");
        }
        public void SelectFirstSheet()
        {
            if (_workbook.NumberOfSheets == 0)
            {
                AddSheet("Sheet1");

            }
            _sheet = _workbook.GetSheetAt(0);
        }
        public void AddSheet(string sheetName)
        {
            _sheet = _workbook.CreateSheet(sheetName);
        }
        public ICell GetCell(int row, int column)
        {
            IRow sheetRow = (IRow)_sheet.GetRow(row);
            if (sheetRow == null)
            {
                sheetRow = (IRow)_sheet.CreateRow(row);
            }
            ICell cell = sheetRow.GetCell(column);
            if (cell == null)
                cell = sheetRow.CreateCell(column);
            return cell;
        }
        public void SetCellValue(int row, int column, string value)
        {
            ICell cell = GetCell(row, column);
            cell.SetCellValue(value);
        }
        public void SetCellValue(int row, int column, Double value)
        {
            ICell cell = GetCell(row, column);
            cell.SetCellValue(value);
        }
        public void SetCellValue(int row, int column, DateTime value)
        {
            ICell cell = GetCell(row, column);
            cell.SetCellValue(value);
        }
        public void SetCellValue(int row, int column, bool value)
        {
            ICell cell = GetCell(row, column);
            cell.SetCellValue(value);
        }
        public void SetCellValue(int row, int column, IRichTextString value)
        {
            ICell cell = GetCell(row, column);
            cell.SetCellValue(value);
        }
        public void InsertDataTable(System.Data.DataTable dt)
        {

            for (int i = 0; i <= dt.Columns.Count - 1; i++)
            {

                GetCell(0, i).SetCellValue(dt.Columns[i].ColumnName);
            }

            for (int i = 0; i <= dt.Rows.Count - 1; i++)
            {

                for (int j = 0; j <= dt.Columns.Count - 1; j++)
                {
                    ICell cell = GetCell(i + 1, j);

                    cell.SetCellValue(dt.Rows[i][j].ToString());


                }

            }

        }
        public void Save()
        {
            if (_fileStream == null)
            {
                throw new Exception("_fileStream不能为空");
            }
            _workbook.Write(_fileStream);
            _fileStream.Close();
            _workbook.Close();
        }
        public void Save(string fileName)
        {
            FileStream fileStream = new FileStream(fileName, FileMode.Create);
            try
            {
                _workbook.Write(fileStream);

            }
            finally
            {
                fileStream.Close();
                _workbook.Close();
            }


        }

        public void Dispose()
        {
            Dispose(true);
            GC.SuppressFinalize(this);
        }
        protected virtual void Dispose(bool disposing)
        {
            if (!this._disposed)
            {
                if (disposing)
                {
                    if (_fileStream != null)
                        _fileStream.Close();
                }

                _fileStream = null;
                _disposed = true;
            }
        }
    }
}