using System;
using System.Collections.Generic;
using System.Text;
using System.Text.RegularExpressions;

namespace Nikse.SubtitleEdit.Core.SubtitleFormats
{
    public class FabSubtitler : SubtitleFormat
    {
        private static readonly Regex RegexTimeCodes = new Regex(@"^\d\d:\d\d:\d\d:\d\d  \d\d:\d\d:\d\d:\d\d$", RegexOptions.Compiled);

        public override string Extension => ".txt";

        public override string Name => "FAB Subtitler";

        public override string ToText(Subtitle subtitle, string title)
        {
            var sb = new StringBuilder();
            const string writeFormat = "{0}  {1}{2}{3}{2}";
            foreach (Paragraph p in subtitle.Paragraphs)
            {
                //00:50:34:22  00:50:39:13
                //Ich muss dafür sorgen,
                //dass die Epsteins weiterleben
                sb.AppendLine(string.Format(writeFormat, EncodeTimeCode(p.StartTime), EncodeTimeCode(p.EndTime), Environment.NewLine, HtmlUtil.RemoveHtmlTags(p.Text)));
            }
            return sb.ToString();
        }

        private static string EncodeTimeCode(TimeCode time)
        {
            //00:50:39:13 (last is frame)
            return $"{time.Hours:00}:{time.Minutes:00}:{time.Seconds:00}:{MillisecondsToFramesMaxFrameRate(time.Milliseconds):00}";
        }

        public override void LoadSubtitle(Subtitle subtitle, List<string> lines, string fileName)
        {
            //00:03:15:22  00:03:23:10 This is line one.
            //This is line two.
            Paragraph p = null;
            subtitle.Paragraphs.Clear();
            _errorCount = 0;
            foreach (string line in lines)
            {
                if (RegexTimeCodes.IsMatch(line))
                {
                    string temp = line.Substring(0, RegexTimeCodes.Match(line).Length);
                    string start = temp.Substring(0, 11);
                    string end = temp.Substring(13, 11);

                    string[] startParts = start.Split(SplitCharColon, StringSplitOptions.RemoveEmptyEntries);
                    string[] endParts = end.Split(SplitCharColon, StringSplitOptions.RemoveEmptyEntries);
                    if (startParts.Length == 4 && endParts.Length == 4)
                    {
                        p = new Paragraph(DecodeTimeCodeFramesFourParts(startParts), DecodeTimeCodeFramesFourParts(endParts), string.Empty);
                        subtitle.Paragraphs.Add(p);
                    }
                }
                else if (string.IsNullOrWhiteSpace(line))
                {
                    // skip these lines
                }
                else if (p != null)
                {
                    if (string.IsNullOrEmpty(p.Text))
                        p.Text = line;
                    else
                        p.Text = p.Text + Environment.NewLine + line;
                }
            }

            subtitle.Renumber();
        }
    }
}