vknet_vk/VkNet/Model/Template/Carousel/CarouselElementBuilder.cs

using System;
using System.Collections.Generic;
using JetBrains.Annotations;
using VkNet.Enums.StringEnums;
using VkNet.Exception;

namespace VkNet.Model;

/// <inheritdoc cref="ICarouselElementBuilder" />
[Serializable]
[UsedImplicitly]
public class CarouselElementBuilder : ICarouselElementBuilder
{
	/// <inheritdoc />
	[CanBeNull]
	public string Title { get; private set; }

	/// <inheritdoc />
	[CanBeNull]
	public string Description { get; private set; }

	/// <inheritdoc />
	[CanBeNull]
	public string PhotoId { get; private set; }

	/// <inheritdoc />
	[CanBeNull]
	public CarouselElementAction Action { get; private set; }

	/// <inheritdoc />
	public List<MessageKeyboardButton> Buttons { get; private set; } = new();

	private readonly string _type;

	private const string Button = "button";

	private int _totalPayloadLength;

	private const string ButtonPayloadLengthExceptionTemplate = "Для кнопки payload должен быть максимум 255 символов: {0}";

	private const string SumPayloadLengthExceptionTemplate =
		"Суммарная длина для payload всех кнопок должен быть максимум 1000 символов.";

	private const string TooMuchButtonsExceptionTemplate = "Количество кнопок не должно превышать трех";

	/// <inheritdoc />
	public CarouselElementBuilder() : this(Button)
	{
	}

	/// <summary>
	/// Инициализирует новый экземпляр класса <see cref="CarouselElementBuilder" />
	/// </summary>
	public CarouselElementBuilder(string type) => _type = type;

	/// <inheritdoc />
	public ICarouselElementBuilder AddButton(string label, string extra, KeyboardButtonColor? color = default, string type = null)
	{
		color ??= KeyboardButtonColor.Default;
		type ??= _type ?? Button;
		var payload = $"{{\"{type}\":\"{extra}\"}}";
		_totalPayloadLength += payload.Length;

		if (Buttons.Count >= 3)
		{
			throw new TooMuchButtonsException(TooMuchButtonsExceptionTemplate);
		}

		if (payload.Length > 255 && type == Button)
		{
			throw new VkKeyboardPayloadMaxLengthException(string.Format(ButtonPayloadLengthExceptionTemplate, payload));
		}

		if (_totalPayloadLength > 1000)
		{
			throw new VkKeyboardPayloadMaxLengthException(SumPayloadLengthExceptionTemplate);
		}

		Buttons.Add(new()
		{
			Color = color,
			Action = new()
			{
				Label = label,
				Payload = payload,
				Type = KeyboardButtonActionType.Text
			}
		});

		return this;
	}

	/// <inheritdoc />
	public ICarouselElementBuilder SetTitle(string title)
	{
		Title = title;

		return this;
	}

	/// <inheritdoc />
	public ICarouselElementBuilder SetDescription(string description)
	{
		Description = description;

		return this;
	}

	/// <inheritdoc />
	public ICarouselElementBuilder SetPhotoId(string photoId)
	{
		PhotoId = photoId;

		return this;
	}

	/// <inheritdoc />
	public ICarouselElementBuilder SetAction(CarouselElementAction action)
	{
		Action = action;

		return this;
	}

	/// <inheritdoc />
	public ICarouselElementBuilder ClearButtons()
	{
		Buttons.Clear();

		return this;
	}

	/// <inheritdoc />
	public CarouselElement Build() => new()
	{
		Title = Title,
		Description = Description,
		PhotoId = PhotoId,
		Buttons = Buttons,
		Action = Action
	};
}