got assignment template variables and replacement working

Management.Web/Shared/Module/Assignment/AssignmentDetails.razor

@@ -134,7 +134,23 @@
       <div class="card-text">
         <div class="row">
           <div class="col">
-            @Assignment.description
+            @if(Assignment.use_template)
+            {
+              var template = planner.LocalCourse?.AssignmentTemplates.First((t) => t.Id == Assignment.template_id);
+              if(template == null)
+              {
+                System.Console.WriteLine($"Could not find template fof assignment, {Assignment.template_id}");
+              }
+              else
+              {
+                var html = AssignmentTemplate.GetHtml(template, Assignment);
+                @((MarkupString) html)
+              }
+            }
+            else
+            {
+              @Assignment.description
+            }
             
           </div>
           <div class="col-auto">

Management.Web/Shared/Module/Assignment/AssignmentForm/AssignmentDescriptionEditor.razor

@@ -9,6 +9,8 @@
   public bool UseTemplate { get; set; }
   [Parameter]
   public string? TemplateId { get; set; }
+  [Parameter]
+  public Dictionary<string, string> VariableValues { get; set; } = new Dictionary<string, string>();
 
   [Parameter]
   public EventCallback<string> DescriptionChanged { get; set; }
@@ -19,12 +21,14 @@
   [Parameter]
   public EventCallback<string?> TemplateIdChanged { get; set; }
 
-  private string selectedTemplateId { get; set; }
+  [Parameter]
+  public EventCallback<Dictionary<string, string>> VariableValuesChanged { get; set; }
+
   private AssignmentTemplate? selectedTemplate => 
     planner
     .LocalCourse?
     .AssignmentTemplates
-    .FirstOrDefault(t => t.Id == selectedTemplateId);
+    .FirstOrDefault(t => t.Id == TemplateId);
 
 }
 
@@ -55,8 +59,14 @@
       <div class="col-auto text-center">
         <form @onsubmit:preventDefault="true">
           <label for="templateSelect">Templates</label>
-          <select id="templateSelect" class="form-select" @bind="selectedTemplateId">
-            <option></option>
+          <select 
+            id="templateSelect" 
+            class="form-select" 
+            value="@TemplateId"
+            @onchange="async (e) =>
+              await TemplateIdChanged.InvokeAsync(e.Value?.ToString())"
+          >
+            <option value=""></option>
             @foreach (var template in planner.LocalCourse.AssignmentTemplates)
             {
               <option value="@template.Id">@template.Name</option>
@@ -79,6 +89,16 @@
               </label>
               <input
                 class="form-control"
+                value="@VariableValues.GetValueOrDefault(variable, String.Empty)"
+                @oninput="async (e) => 
+                  {
+                    var newValue = e.Value?.ToString() ?? String.Empty;
+                    var newDictionary = new Dictionary<string, string>(VariableValues);
+                    newDictionary[variable] = newValue;
+                    
+                    await VariableValuesChanged.InvokeAsync(newDictionary);
+                  }
+                "
               />
             </div>
           }

Management.Web/Shared/Module/Assignment/AssignmentForm/AssignmentForm.razor

@@ -55,6 +55,7 @@
       .Where(r => !r.Label.Contains(RubricItem.extraCredit))
       .Select(s => s.Points)
       .Sum();
+
     var newAssignment = Assignment with 
     {
       name=name,
@@ -117,6 +118,7 @@
           @bind-Description="description"
           @bind-UseTemplate="useTemplate"
           @bind-TemplateId="templateId"
+          @bind-VariableValues="templateVariables"
         />
       </div>