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

namespace BBcode_Fixer
{
    class Program
    {
        static void Main(string[] args)
        {
            string filename, fileline, matchstring, tempstring = "";
            string concatstring = "";
            Console.Write("Put text file in same location as this app\nEnter text file name (include .txt): ");
            filename = Console.ReadLine();
            Console.WriteLine(filename + "\n");
            try
            {
                using (StreamReader postcontent = new StreamReader(filename, Encoding.UTF8))
                {
                    Console.WriteLine("File found!");
                    Regex rx = new Regex(@"\[(td)\].*?\[(\/td)\]", RegexOptions.IgnoreCase | RegexOptions.Multiline);
                    Regex tagfinder = new Regex(@"\[\S*?\]", RegexOptions.IgnoreCase);
                    fileline = postcontent.ReadToEnd();
                    fileline = Regex.Replace(fileline, @"((pt)\])", "px]");
                    fileline = Regex.Replace(fileline, @"\[((table)\])", "[table=noborder]");
                    MatchCollection rawmatches = rx.Matches(fileline);
                    foreach (Match match in rawmatches)
                    {
                        matchstring = match.Value;
                        Console.WriteLine("Old String:\n'{0}' at position {1}",
                              match.Value,
                              match.Index);
                        Console.WriteLine(matchstring + "\n");
                        if (matchstring != "[td][/td]")
                        {
                            matchstring = matchstring.Substring(4, matchstring.Length - 9);
                            matchstring = Regex.Replace(matchstring, @"\[\/.*?\]", "");
                            tempstring = Regex.Replace(matchstring, @"=.*?]", "]");
                            MatchCollection tagmatches = tagfinder.Matches(tempstring);
                            foreach (Match foundtag in tagmatches)
                            {
                                concatstring = "[/" + foundtag.Value.Substring(1, foundtag.Value.Length-1) + concatstring;
                            }
                            matchstring = "[td]" + matchstring + concatstring + "[/td]";
                            Console.WriteLine(matchstring);
                            fileline = fileline.Replace(match.Value, matchstring);
                            tempstring = "";
                            concatstring = "";
                            matchstring = "";
                        }
                    }
                    postcontent.Close();
                }
                StreamWriter writer = new StreamWriter("output.txt");
                writer.WriteLine(fileline);
                writer.Close();
            }
            catch (IOException e)
            {
                Console.WriteLine("The file could not be read:");
                Console.WriteLine(e.Message);
            }
            Console.ReadKey();
        }
    }
}