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

namespace Eugen.ESystem.Windows.Forms
{
    public static class FixLineLenght
    {
        /// <summary>
		/// Formats a string with a fixed line length.
		/// </summary>
		static FixLineLenght()
        {
        }

        /// <summary>
        /// Formats a string with a fixed line length.
        /// </summary>
        /// <param name="text">String to be formatted.</param>
        /// <param name="lineLenght">Maximum line length</param>
        /// <returns></returns>
        public static string Format(string text, int lineLenght)
        {
            int ratedLenght = 0;
            int spacePos = 0;
            int currentPos = 0;
            string character = "";
            string resultText = "";

            if (text.Length <= lineLenght)
            {
                resultText = text;
            }
            else
            {
                while (text.Length > 0)
                {
                    while (ratedLenght < lineLenght)
                    {
                        if (currentPos < text.Length)
                        {
                            character = text.Substring(currentPos, 1);
                        }
                        else
                        {
                            break;
                        }

                        if (character == "\n" || character == "\r")
                        {
                            currentPos++;
                            ratedLenght = 0;
                        }

                        if (character == " " || character == "\\")
                        {
                            spacePos = currentPos;
                        }

                        currentPos++;
                        ratedLenght++;
                    }

                    if (spacePos == 0)
                    {
                        spacePos = currentPos;
                    }

                    if (text.Length <= lineLenght || text.Length == spacePos)
                    {
                        resultText = resultText + text;
                        text = "";
                    }
                    else
                    {
                        resultText = resultText + text.Remove(spacePos) + Environment.NewLine;

                        text = text.Remove(0, spacePos);

                        if (text.StartsWith(" "))
                        {
                            text = text.Remove(0, 1);
                        }
                    }

                    ratedLenght = 0;
                    currentPos = 0;
                    spacePos = 0;
                }
            }

            resultText = CorrectLastLine(resultText, lineLenght);

            return resultText;
        }

        private static string CorrectLastLine(string text, int lineLenght)
        {
            string tempMid = "";
            string tempEnd = "";

            tempEnd = text.Remove(0, text.LastIndexOf(Environment.NewLine) + 2);
            tempMid = text.Remove(text.LastIndexOf(Environment.NewLine));
            tempMid = tempMid.Remove(0, tempMid.LastIndexOf(Environment.NewLine) + 2);

            if ((tempMid.Length + tempEnd.Length) <= lineLenght)
            {
                return text.Remove(text.LastIndexOf(Environment.NewLine), 2);
            }
            else
            {
                return text;
            }
        }
    }
}