telegram-bot/modules/RichSiteSummary/Data/RepresentableEntity.cs

// This file is a part of RSS Bot for Telegram.
// License: MIT
// Author: CrazyHackGUT aka Kruzya (Sergey Gut) <kruzefag@gmail.com>
// 

using System;
using System.Web;
using Telegram.Bot.Types.Enums;

namespace Kruzya.TelegramBot.RichSiteSummary.Data;

/// <summary>
/// Implements the basic logic for rendering Database Entities in messages.
/// </summary>
public abstract class RepresentableEntity
{
    protected virtual string ViewableText { get; }
    protected virtual string ViewableUrl { get; }
    protected virtual ParseMode DefaultRepresentation { get; }

    public override string ToString() => Representation();

    public string Representation(string text) => Representation(DefaultRepresentation, text);
        
    public string Representation() => Representation(DefaultRepresentation);
        
    public string Representation(ParseMode parseMode) => Representation(parseMode, ViewableText);
        
    public string Representation(ParseMode parseMode, string text)
    {
        string content = String.Empty;
        switch (parseMode)
        {
            case ParseMode.Html:
                content = HtmlRepresentation(text);
                break;
                
            case ParseMode.Markdown:
            case ParseMode.MarkdownV2:
                throw new NotImplementedException();
        }

        return content;
    }

    #region Representations

    public string RawRepresentation(string text)
        => text;

    public string HtmlRepresentation(string text)
    {
        var escapedText = HttpUtility.HtmlEncode(text);
        var escapedUrl = HttpUtility.HtmlAttributeEncode(ViewableUrl);

        return $"<a href=\"{escapedUrl}\">{escapedText}</a>";
    }
        
    #endregion
}