add new tag helpers

TurnstileScriptTagHelper.cs

@@ -0,0 +1,48 @@
+using Microsoft.AspNetCore.Mvc.Rendering;
+using Microsoft.AspNetCore.Mvc.ViewFeatures;
+using Microsoft.AspNetCore.Razor.TagHelpers;
+using Microsoft.Extensions.Options;
+
+namespace TurnstileTag;
+
+[HtmlTargetElement("cf-turnstile-script", TagStructure = TagStructure.NormalOrSelfClosing)]
+public class TurnstileScriptTagHelper : TagHelper
+{
+  /// <summary>
+  /// Force rendering of script tag.
+  /// Otherwise it is only rendered when a turnstile input was rendered.
+  /// </summary>
+  public bool Force { get; set; }
+
+  readonly IOptions<TurnstileOptions> _options;
+
+  /// <summary>
+  /// Gets the <see cref="Rendering.ViewContext"/> of the executing view.
+  /// </summary>
+  [HtmlAttributeNotBound]
+  [ViewContext]
+  public ViewContext? ViewContext { get; set; }
+
+
+  public TurnstileScriptTagHelper(IOptions<TurnstileOptions> options)
+  {
+    _options = options;
+  }
+
+
+  public override void Process(TagHelperContext context, TagHelperOutput output)
+  {
+    if (Force || (ViewContext != null && ViewContext.ViewData.ContainsKey("turnstile")))
+    {
+      output.TagMode = TagMode.StartTagAndEndTag;
+      output.TagName = "script";
+      output.Attributes.Add(new TagHelperAttribute("async"));
+      output.Attributes.Add(new TagHelperAttribute("defer"));
+      output.Attributes.Add("src", _options.Value.ApiUrl + "/api.js");
+    }
+    else 
+    {
+      output.SuppressOutput();
+    }
+  }
+}