telegram-bot/modules/RichSiteSummary/UrchinTrackingModule/UtmUtility.cs

using System;
using System.Collections.Generic;
using System.Collections.Specialized;
using System.Web;

namespace Kruzya.TelegramBot.RichSiteSummary.UrchinTrackingModule;

public class UtmUtility
{
    public static string ApplyParameters(string url, UtmParameters parameters)
        => ApplyParameters(new Uri(url), parameters);

    public static string ApplyParameters(Uri uri, UtmParameters parameters)
    {
        var query = HttpUtility.ParseQueryString(uri.Query);

        SetIfNotNull(query, "utm_source", parameters.Source);
        SetIfNotNull(query, "utm_medium", parameters.Type);
        SetIfNotNull(query, "utm_campaign", parameters.Campaign);
        SetIfNotNull(query, "utm_term", parameters.Term);
        SetIfNotNull(query, "utm_content", parameters.Content);

        var uriBuilder = new UriBuilder(uri);
        uriBuilder.Query = BuildQueryString(query);
        return uriBuilder.ToString();
    }

    protected static string BuildQueryString(NameValueCollection query)
    {
        var queryParameters = new List<string>();

        foreach (var keyName in query.AllKeys)
        {
            var value = query[keyName];
            queryParameters.Add($"{HttpUtility.UrlEncode(keyName)}={HttpUtility.UrlEncode(value)}");
        }

        return String.Join('&', queryParameters);
    }
        
    protected static void SetIfNotNull(NameValueCollection queryParameteters, string key, string value)
    {
        if (string.IsNullOrWhiteSpace(value))
        {
            return;
        }
            
        queryParameteters.Set(key, value);
    }
}