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using ClosedXML.Excel;
using System.Data;
using System.IO;

namespace ExcelReport
{
    public class Program
    {
        static readonly int firstDtilRow = 16;

        static void Main(string[] args)
        {
            string tmppath = @".\template.xlsx";
            string outpath = @".\Test.xlsx";

            if (!File.Exists(tmppath))
            {
                throw new FileNotFoundException("テンプレートファイルが存在しません。");
            }

            if (File.Exists(outpath))
            {
                File.Delete(outpath);
            }

            File.Copy(tmppath, outpath);

            var book = new XLWorkbook(outpath);
            var tmpsheet = book.Worksheet(1);

            // ヘッダ部データの取得
            DataTable dh = SampleData.SampleDataHeader();

            // ヘッダ毎にシートを作成する
            for (int i = 1; i <= dh.Rows.Count; i++)
            {
                if (i > 1)
                {
                    tmpsheet.CopyTo("Sheet" + (i).ToString(), i);
                }
            }
            
            for (int i = 0; i < dh.Rows.Count; i++)
            {
                var sheet = book.Worksheet(i + 1);

                // ヘッダデータのセット
                foreach (var row in sheet.RangeUsed().Rows())
                {
                    SetData("datetime", row, dh.Rows[i]);
                    SetData("comp", row, dh.Rows[i]);
                    SetData("dept", row, dh.Rows[i]);
                    SetData("name", row, dh.Rows[i]);
                    SetData("postalcode", row, dh.Rows[i]);
                    SetData("address1", row, dh.Rows[i]);
                    SetData("address2", row, dh.Rows[i]);
                    SetData("mycomp", row, dh.Rows[i]);
                    SetData("mydept", row, dh.Rows[i]);
                    SetData("myuser", row, dh.Rows[i]);
                    SetData("mypostalcode", row, dh.Rows[i]);
                    SetData("myaddress1", row, dh.Rows[i]);
                    SetData("myaddress2", row, dh.Rows[i]);
                    SetData("myphone", row, dh.Rows[i]);
                    SetData("deliperiod", row, dh.Rows[i]);
                    SetData("val", row, dh.Rows[i]);
                }

                DataTable dd = SampleData.SampleDataDetail(dh.Rows[i]);
                
                if (dd.Rows.Count > 1)
                {
                    sheet.Row(firstDtilRow).InsertRowsBelow(dd.Rows.Count - 1);
                    for (int j = 1; j < dd.Rows.Count; j++)
                    {
                        // 行をコピーすると書式等が消えるため、再設定
                        sheet.Row(firstDtilRow + j).Height = 15;
                        sheet.Range(firstDtilRow + j, 2, firstDtilRow + j, 9).Merge(false);
                        sheet.Range(firstDtilRow + j, 10, firstDtilRow + j, 23).Merge(false);
                        sheet.Range(firstDtilRow + j, 24, firstDtilRow + j, 30).Merge(false);
                        sheet.Range(firstDtilRow + j, 31, firstDtilRow + j, 33).Merge(false);
                        sheet.Range(firstDtilRow + j, 34, firstDtilRow + j, 40).Merge(false);
                        sheet.Range(firstDtilRow + j, 41, firstDtilRow + j, 47).Merge(false);
                    }
                }
                // 明細データのセット
                InsertData(sheet, dd.Rows, firstDtilRow);
            }

            book.Save();
        }

        /// <summary>
        /// offset位置からの明細データのセット
        /// </summary>
        /// <param name="sheet"></param>
        /// <param name="rows"></param>
        /// <param name="offset"></param>
        private static void InsertData(IXLWorksheet sheet, DataRowCollection rows, int offset)
        {
            for (int i = 0; i < rows.Count; i++)
            {
                sheet.Cell(offset + i, 2).Value = rows[i]["prodcode"].ToString();
                sheet.Cell(offset + i, 10).Value = rows[i]["prodname"].ToString();
                sheet.Cell(offset + i, 24).Value = rows[i]["qt"];
                sheet.Cell(offset + i, 31).Value = rows[i]["unit"].ToString();
                sheet.Cell(offset + i, 34).Value = rows[i]["price"];
                sheet.Cell(offset + i, 41).Value = rows[i]["amount"];
            }
        }

        /// <summary>
        /// テンプレートの書式（${templateName}）に値をセットする
        /// </summary>
        /// <param name="templateName"></param>
        /// <param name="row"></param>
        /// <param name="dr"></param>
        private static void SetData(string templateName, IXLRangeRow row, DataRow dr)
        {
            string searchName = "${" + templateName + "}";
            row.Search(searchName).Value = dr[templateName].ToString();
        }
    }
}