//	Spludlow Software
//	Copyright © Samuel P. Ludlow 2020 All Rights Reserved
//	Distributed under the terms of the GNU General Public License version 3
//	Distributed WITHOUT ANY WARRANTY; without implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE
//	https://www.spludlow.co.uk/LICENCE.TXT
//	The Spludlow logo is a registered trademark of Samuel P. Ludlow and may not be used without permission
//	v1.14

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

using System.IO;
using System.Data;

namespace Spludlow
{
	public class ASCII
	{
		private static string TableFilename = Spludlow.Config.ProgramData + @"\Data\ASCII.txt";

		public static DataTable Table = null;

		static ASCII()
		{
			if (File.Exists(TableFilename) == true)
			{
				Table = Spludlow.Data.TextTable.ReadFile(TableFilename);
			}
		}

		public static void MakeTable()
		{
			//	ASCIINames.txt from http://ascii-code.com/
			//	Need to fix row	127	DEL			Delete
			//	Blank out all names except control; <32 =127
			//	and Tidy up few descriptions
			//	Id	Name	Number	HTML	Description

			//	The GBP sign has number 163 in ISO-8859-1 (Latin-1) and Unicode
			//	GBP sign number is 156 in "Code page 437" (DOS)

			DataTable namesTable = Spludlow.Data.TextTable.ReadFile(Spludlow.Config.ProgramData + @"\Data\ASCIINames.txt");

			DataTable table = Spludlow.Data.TextTable.ReadText(new string[]
			{
				"CharId	CharName	CharDesc	Printable	HTML	CharValue	StringValue",
				"Int32*	String		String		Boolean		String	Char		String",
			});

			Spludlow.Data.TextTable.Write(TableFilename, table);

			byte[] newLine = Encoding.ASCII.GetBytes(Environment.NewLine);
			byte[] tab = Encoding.ASCII.GetBytes("\t");

			using (FileStream stream = new FileStream(TableFilename, FileMode.Append))
			{
				for (int id = 0; id < 256; ++id)
				{
					DataRow nameRow = namesTable.Rows.Find(id);

					bool printable = true;

					string charName = "";
					string charDesc = "";

					if (id < 32 || id == 127)
					{
						printable = false;
						charName = (string)nameRow["Name"];
						charDesc = (string)nameRow["Description"];
					}
					
					if (printable == true && nameRow.IsNull("Number") == true)
						printable = false;

					string html = "";
					if (nameRow.IsNull("HTML") == false)
						html = (string)nameRow["HTML"];
					
					byte[] buffer;

					buffer = Encoding.ASCII.GetBytes(id.ToString());
					stream.Write(buffer, 0, buffer.Length);

					stream.Write(tab, 0, tab.Length);

					buffer = Encoding.ASCII.GetBytes(charName);
					stream.Write(buffer, 0, buffer.Length);

					stream.Write(tab, 0, tab.Length);

					buffer = Encoding.ASCII.GetBytes(charDesc);
					stream.Write(buffer, 0, buffer.Length);

					stream.Write(tab, 0, tab.Length);

					buffer = Encoding.ASCII.GetBytes(printable.ToString());
					stream.Write(buffer, 0, buffer.Length);

					stream.Write(tab, 0, tab.Length);

					buffer = Encoding.ASCII.GetBytes(html);
					stream.Write(buffer, 0, buffer.Length);

					stream.Write(tab, 0, tab.Length);

					if (printable == true)
					{
						buffer = new byte[1];
						buffer[0] = (byte)id;
					}
					else
					{
						buffer = new byte[0];
					}

					stream.Write(buffer, 0, buffer.Length);

					stream.Write(tab, 0, tab.Length);

					stream.Write(buffer, 0, buffer.Length);

					stream.Write(newLine, 0, newLine.Length);
				}
			}
		}
	}
}