Umbraco related HTML helper extension methods

UmbracoHtmlHelperExtensions.cs

using System.Text;
using Microsoft.AspNetCore.Html;
using Microsoft.AspNetCore.Mvc.Rendering;
using Microsoft.AspNetCore.Mvc.ViewFeatures;
using Umbraco.Cms.Core.Models;
using Umbraco.Extensions;

namespace Concept.Core.Extensions
{
  public static class HtmlHelperExtensions
  {
    public static HtmlString ResponsiveImage(this IHtmlHelper helper, MediaWithCrops media, string defaultCrop = "xs", object? htmlAttributes = null)
    {
      TagBuilder tagBuilder = new TagBuilder("img")
      {
        TagRenderMode = TagRenderMode.SelfClosing
      }
      
      var attributes = HtmlHelper.AnonymousObjectToHtmlAttributes(htmlAttributes);
      
      tagBuilder.MergeAttributes(attributes);
      tagBuilder.MergeAttribute("src", string.IsNullOrWhiteSpace(defaultCrop)
        ? media.GetCropUrl(furtherOptions: "&format=webp")
        : media.GetCropUrl(cropAlias: defaultCrop, useCropDimensions: true, furtherOptions: "&format=webp"));
        
      if(media.LocalCrops == null) return new HtmlString(tagBuilder.ToHtmlString());
      
      tagBuilder.MergeAttribute("srcset", media.GetSrcSet().ToString());
      
      return new HtmlString(tagBuilder.ToHtmlString());
    }

    public static HtmlString ResponsiveImage(this IHtmlHelper helper, MediaWithCrops media, string defaultCrop = "xs", string sizes = "100vw", object? htmlAttributes = null)
    {
      TagBuilder tagBuilder = new TagBuilder("img")
      {
        TagRenderMode = TagRenderMode.SelfClosing
      }
      
      var attributes = HtmlHelper.AnonymousObjectToHtmlAttributes(htmlAttributes);
      
      tagBuilder.MergeAttributes(attributes);
      tagBuilder.MergeAttribute("src", string.IsNullOrWhiteSpace(defaultCrop)
        ? media.GetCropUrl(furtherOptions: "&format=webp")
        : media.GetCropUrl(cropAlias: defaultCrop, useCropDimensions: true, furtherOptions: "&format=webp"));
        
      if(media.LocalCrops == null) return new HtmlString(tagBuilder.ToHtmlString());
      
      tagBuilder.MergeAttribute("srcset", media.GetSrcSet().ToString());
      
      if(sizes.IsNullOrWhiteSpace()) return new HtmlString(tagBuilder.ToHtmlString());
      
      tagBuilder.MergeAttributes("sizes", sizes);
      
      return new HtmlString(tagBuilder.ToHtmlString());
    }
    
    public static HtmlString GetSrcSet(this MediaWithCrops media)
    {
      StringBuilder sb = new StringBuilder(string.Empty);
      
      foreach(var crop in media.LocalCrops.Crops)
      {
        sb.Append(media.GetCropUrl(cropAlias: crop.Alias, useCropDimensions: true, furtherOptions: "&format=webp"));
        sb.Append(" ");
        sp.Append(crop.Width);
        sp.Append("w");
        
        if(crop != media.LocalCrops.Crops.Last())
        {
          sb.Append(",");
        }
      }
      
      return (new HtmlString(sb.ToString());
    }
  }
}