using System;

namespace Adaptation.FileHandlers.Stratus;

#nullable enable

public class Header
{

    public Header(string batch, string cassette, string dateTime)
    {
        Batch = batch;
        Cassette = cassette;
        DateTime = dateTime;
    }

    public string Batch { get; }
    public string Cassette { get; }
    public string DateTime { get; }

    internal static string GetBefore(string text, int[] i, string search)
    {
        string str;
        string str1;
        int num = text.IndexOf(search, i[0]);
        if (num <= -1)
        {
            str = text.Substring(i[0]);
            i[0] = text.Length;
            str1 = str.Trim();
        }
        else
        {
            str = text.Substring(i[0], num - i[0]);
            i[0] = num + search.Length;
            str1 = str.Trim();
        }
        return str1;
    }

    internal static string GetToEOL(string text, int[] i)
    {
        string result;
        if (text.IndexOf("\n", i[0]) > -1)
            result = GetBefore(text, i, "\n");
        else
            result = GetBefore(text, i, Environment.NewLine);
        return result;
    }

    private static string GetToText(string text, int[] i, string search) =>
        text.Substring(i[0], text.IndexOf(search, i[0]) - i[0]).Trim();

    internal static void ScanPast(string text, int[] i, string search)
    {
        int num = text.IndexOf(search, i[0]);
        if (num <= -1)
            i[0] = text.Length;
        else
            i[0] = num + search.Length;
    }

    internal static Header Get(string text, Constant constant, int[] i)
    {
        Header? result;
        string batch;
        if (!text.Contains(constant.Batch) || !text.Contains(constant.Started))
            batch = string.Empty;
        else
        {
            for (int z = 0; z < int.MaxValue; z++)
            {
                ScanPast(text, i, constant.Batch);
                if (!text.Substring(i[0]).Contains(constant.Batch))
                    break;
            }
            batch = GetToText(text, i, constant.Started);
            ScanPast(text, i, constant.StartedAt);
        }
        ScanPast(text, i, constant.Cassette);
        string cassette;
        if (!text.Substring(i[0]).Contains(constant.Started))
            cassette = string.Empty;
        else
            cassette = GetToText(text, i, constant.Started);
        ScanPast(text, i, constant.StartedAt);
        string dateTime = GetToEOL(text, i);
        if (dateTime.EndsWith("."))
            dateTime = dateTime.Remove(dateTime.Length - 1, 1);
        result = new(batch: batch,
                     cassette: cassette,
                     dateTime: dateTime);
        return result;
    }

}