using System;

namespace Questionable.Model.Questing;

public class ExcelRef
{
	public enum EType
	{
		None,
		Key,
		RowId,
		RawString
	}

	private readonly string? _stringValue;

	private readonly uint? _rowIdValue;

	public EType Type { get; }

	public ExcelRef(string value)
	{
		_stringValue = value;
		_rowIdValue = null;
		Type = EType.Key;
	}

	public ExcelRef(uint value)
	{
		_stringValue = null;
		_rowIdValue = value;
		Type = EType.RowId;
	}

	private ExcelRef(string? stringValue, uint? rowIdValue, EType type)
	{
		_stringValue = stringValue;
		_rowIdValue = rowIdValue;
		Type = type;
	}

	public static ExcelRef FromKey(string value)
	{
		return new ExcelRef(value, null, EType.Key);
	}

	public static ExcelRef FromRowId(uint rowId)
	{
		return new ExcelRef(null, rowId, EType.RowId);
	}

	public static ExcelRef FromSheetValue(string value)
	{
		return new ExcelRef(value, null, EType.RawString);
	}

	public string AsKey()
	{
		if (Type != EType.Key)
		{
			throw new InvalidOperationException();
		}
		return _stringValue;
	}

	public uint AsRowId()
	{
		if (Type != EType.RowId)
		{
			throw new InvalidOperationException();
		}
		return _rowIdValue.Value;
	}

	public string AsRawString()
	{
		if (Type != EType.RawString)
		{
			throw new InvalidOperationException();
		}
		return _stringValue;
	}
}