using System;
using System.IO;
using System.Text;
using System.Text.RegularExpressions;

namespace SystemName
{
    class Programm
    {
        static void Main(string[] args)
        {
            SubtitleFix.SubtitleFixer();
        }
    }
    class SubtitleFix
    {
        private const string Value = ".";
        static readonly string FIRST_PATH = @"D:\Работа\Монтаж\Ролики\Аудио\в благодарность.txt";
        static readonly string SECOND_PATH = @"D:\Работа\Монтаж\Ролики\Аудио\в благодарность текст.txt";

        public static (string,string) ReadFiles()
        {
            var FirstText = File.ReadAllText(FIRST_PATH);
            var SecondText = File.ReadAllText(SECOND_PATH);

            return (FirstText, SecondText);
        }

        public static void SubtitleFixer ()
        {
            string pattern = @"\d\d:\d\d:\d\d:\d\d - \d\d:\d\d:\d\d:\d\d\r\nНеизвестный";
            var text1 = ReadFiles().Item1;
            var text2 = ReadFiles().Item2;
            var startIndex = 0;
            var endIndex = 0;
            string result = "";
            var k = 0;
            var matches = Regex.Matches(text1, pattern);
            var n = 0;
            var currentBlock = "";
            for (int i = 0;i < text1.Length;i++)
            {
                if (i + 11 < text1.Length && text1.Substring(i,11) == "Неизвестный" && k + currentBlock.Length < text2.Length)
                {
                    if (startIndex == 0)
                    {
                        startIndex = i + 11;
                        result += matches[n].Value + "\n";
                        n++;
                    }
                    else
                    {
                        endIndex = i - 27;
                        var shift = text2.Substring(0, k + endIndex - startIndex + 15).LastIndexOf('.');
                        currentBlock = text2.Substring(k, shift - k + 1) ;
                        result = result + currentBlock + "\n\n" + matches[n].Value + "\n";
                        k += currentBlock.Length;
                        startIndex = endIndex;
                        n++;
                    }
                }
            }
            result += text2.Substring(k);
            File.WriteAllText(@"D:\Работа\Монтаж\Ролики\Аудио\в благодарность финал.txt", result);
        }
    }
}