// http://svc.luckstar.com.tw/CodeHelper/cs/index.html
// 2017-04-14, honda@luckstar.com.tw, Create.
// related keyword:
// StreamWriter, UTF8Encoding, ReadLine, EndOfStream, StreamReader, FileStream, PadLeft, PadRight, Len, SubString.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
// add
using System.IO;

namespace ConsoleBase
{
    public class CFileStream
    {
        public void Run()
        {
            FileInfo f1 = new FileInfo("f1.txt");
            decimal dTotalAmt1 = 0;
            string sDashLine = "T ------ ------------------ ------------------";

            Console.WriteLine();
            Console.WriteLine("----------");
            Console.WriteLine("Export fixed length columns of text file with UTF8Encoding for Chinese characters:");
            Console.WriteLine("StreamWriter, UTF8Encoding:");
            using (FileStream stream1 = new FileStream(f1.FullName, FileMode.Create, FileAccess.Write))
            using (StreamWriter wr1 = new StreamWriter(stream1, new UTF8Encoding(false)))
            {
                wr1.WriteLine("T {0} {1} {2}",
                    PadLeftC("No.", 6),
                    PadRightC("Item", 20),
                    PadLeftC("Amount", 16)
                    );

                wr1.WriteLine(sDashLine);

                for (int i = 0; i < 5; i++)
                {
                    decimal dAmt = 7654321 * i + 971;
                    dAmt = decimal.Round(dAmt / 7, 2);

                    dTotalAmt1 += dAmt;
                    wr1.WriteLine("D {0} {1} {2}",
                        PadLeftC(i.ToString(), 6),
                        PadRightC("中文品名" + dAmt.ToString(), 20, true),
                        PadLeftC(dAmt.ToString("#,##0.00"), 16)
                        );
                }
                wr1.WriteLine(sDashLine);
                wr1.WriteLine("S {0} {1} {2}",
                    PadLeftC(" ", 6),
                    PadRightC("Total", 20),
                    PadLeftC(dTotalAmt1.ToString("#,##0.00"), 16)
                    );
            }
            Console.WriteLine("output file {0} as below:", f1.Name);
            Console.WriteLine(File.ReadAllText(f1.FullName));


            Console.WriteLine();
            Console.WriteLine("----------");
            Console.WriteLine("Import fixed length columns of text file with UTF8Encoding for Chinese characters:");
            Console.WriteLine("ReadLine, EndOfStream, StreamReader, FileStream:");

            Console.WriteLine("No.,Item,Amt");

            int iLengthDataLine = sDashLine.Length;
            int iCountData = 0;
            decimal dTotalAmt2 = 0;
            using (FileStream stream1 = new FileStream(f1.FullName, FileMode.Open, FileAccess.Read))
            using (StreamReader rd1 = new StreamReader(stream1, new UTF8Encoding(false)))
            {
                int iLine;
                string sLine;
                string sH;
                string sNo;
                string sItem;
                string sAmt;
                int iNo;
                decimal dAmt;

                iLine = 0;
                while (!rd1.EndOfStream)
                {
                    sLine = rd1.ReadLine();
                    iLine++;
                    if (LenC(sLine, true) != iLengthDataLine)
                        continue;

                    sH = SubStringC(sLine, 0, 1, true).Trim();
                    sNo = SubStringC(sLine, 2, 6, true).Trim();
                    sItem = SubStringC(sLine, 9, 20, true).Trim();
                    sAmt = SubStringC(sLine, 30, 16, true).Trim();
                    if (sH == "D")
                        iCountData++;
                    else
                        continue;

                    if (!int.TryParse(sNo, out iNo))
                        iNo = 0;

                    if (!decimal.TryParse(sAmt, out dAmt))
                        dAmt = 0;

                    dTotalAmt2 += dAmt;
                    Console.WriteLine("{0},{1},{2}", iNo, sItem, dAmt);
                }
                Console.WriteLine("dTotalAmt2={0}", dTotalAmt2.ToString("#,##0.00"));
                if (dTotalAmt1 == dTotalAmt2)
                    Console.WriteLine("dTotalAmt1 == dTotalAmt2");
                else
                    Console.WriteLine("dTotalAmt1 != dTotalAmt2");

            }
        }
        public static int LenC(string sInput)
        {
            return LenC(sInput, false);
        }
        public static int LenC(string sInput, bool bChinese)
        {
            if (bChinese)
            {
                return Encoding.GetEncoding(950).GetByteCount(sInput);
            }
            else
            {
                return sInput.Length;
            }
        }
        public static string PadRightC(string sInput, int iLen)
        {
            return PadRightC(sInput, iLen, ' ', false);
        }
        public static string PadRightC(string sInput, int iLen, Boolean bChinese)
        {
            return PadRightC(sInput, iLen, ' ', bChinese);
        }
        public static string PadRightC(string sInput, int iLen, char c1, Boolean bChinese)
        {
            if (bChinese)
            {
                return sInput + new String(c1, iLen - LenC(sInput, bChinese));
            }
            else
            {
                return sInput.PadRight(iLen, c1);
            }
        }
        public static string PadLeftC(string sInput, int iLen)
        {
            return PadLeftC(sInput, iLen, ' ', false);
        }
        public static string PadLeftC(string sInput, int iLen, Boolean bChinese)
        {
            return PadLeftC(sInput, iLen, ' ', bChinese);
        }

        public static string PadLeftC(string sInput, int iLen, char c1, Boolean bChinese)
        {
            if (bChinese)
            {
                return new String(c1, iLen - LenC(sInput, bChinese)) + sInput;
            }
            else
            {
                return sInput.PadLeft(iLen, c1);
            }
        }
        public static string SubStringC(string sInput, int iStartIndex, int iLen)
        {
            return SubStringC(sInput, iStartIndex, iLen, false);
        }

        public static string SubStringC(string sInput, int iStartIndex, int iLen, bool bChinese)
        {
            if (bChinese)
            {
                return Encoding.GetEncoding(950).GetString(Encoding.GetEncoding(950).GetBytes(sInput), iStartIndex, iLen);
            }
            else
            {
                return sInput.Substring(iStartIndex, iLen);
            }
        }

    }
}



/* 
result:

----------
Export fixed length columns of text file with UTF8Encoding for Chinese characters:
StreamWriter, UTF8Encoding:
output file f1.txt as below:
T    No. Item                           Amount
T ------ ------------------ ------------------
D      0 中文品名138.71                 138.71
D      1 中文品名1093613.14       1,093,613.14
D      2 中文品名2187087.57       2,187,087.57
D      3 中文品名3280562          3,280,562.00
D      4 中文品名4374036.43       4,374,036.43
T ------ ------------------ ------------------
S        Total                   10,935,437.85


----------
Import fixed length columns of text file with UTF8Encoding for Chinese characters:
ReadLine, EndOfStream, StreamReader, FileStream:
No.,Item,Amt
0,中文品名138.71,138.71
1,中文品名1093613.14,1093613.14
2,中文品名2187087.57,2187087.57
3,中文品名3280562,3280562.00
4,中文品名4374036.43,4374036.43
dTotalAmt2=10,935,437.85
dTotalAmt1 == dTotalAmt2

*/