using System;
using System.IO;
using System.Text;
using AspClassic.Scripting.Utils;

namespace AspClassic.Scripting;

public class SourceCodeReader : TextReader
{
	public new static readonly SourceCodeReader Null = new SourceCodeReader(TextReader.Null, null);

	private readonly TextReader _textReader;

	private readonly Encoding _encoding;

	public Encoding Encoding => _encoding;

	public TextReader BaseReader => _textReader;

	public SourceCodeReader(TextReader textReader, Encoding encoding)
	{
		ContractUtils.RequiresNotNull(textReader, "textReader");
		_encoding = encoding;
		_textReader = textReader;
	}

	public override string ReadLine()
	{
		return _textReader.ReadLine();
	}

	public virtual bool SeekLine(int line)
	{
		if (line < 1)
		{
			throw new ArgumentOutOfRangeException("line");
		}
		if (line == 1)
		{
			return true;
		}
		int num = 1;
		while (true)
		{
			switch (_textReader.Read())
			{
			case 13:
				if (_textReader.Peek() == 10)
				{
					_textReader.Read();
				}
				num++;
				if (num == line)
				{
					return true;
				}
				break;
			case 10:
				num++;
				if (num == line)
				{
					return true;
				}
				break;
			case -1:
				return false;
			}
		}
	}

	public override string ReadToEnd()
	{
		return _textReader.ReadToEnd();
	}

	public override int Read(char[] buffer, int index, int count)
	{
		return _textReader.Read(buffer, index, count);
	}

	public override int Peek()
	{
		return _textReader.Peek();
	}

	public override int Read()
	{
		return _textReader.Read();
	}

	protected override void Dispose(bool disposing)
	{
		_textReader.Dispose();
	}
}