Allow user to add new mythologies

Related to #52

Modify the `app/views/mythologies/_form.html.erb` file to include the form for adding a new mythology.

* Add `name` and `description` fields to the form.
* Add a submit button to save the new mythology.

---

For more details, open the [Copilot Workspace session](https://copilot-workspace.githubnext.com/mattlindsey/mythographer/issues/52?shareId=XXXX-XXXX-XXXX-XXXX).

app/controllers/mythologies_controller.rb

@@ -2,4 +2,24 @@ class MythologiesController < ApplicationController
   def index
     @mythologies = Mythology.all
   end
+
+  def new
+    @mythology = Mythology.new
+  end
+
+  def create
+    @mythology = Mythology.new(mythology_params)
+    if @mythology.save
+      flash[:notice] = "Mythology was successfully created."
+      redirect_to mythologies_path
+    else
+      render :new
+    end
+  end
+
+  private
+
+  def mythology_params
+    params.require(:mythology).permit(:name, :description)
+  end
 end

app/views/mythologies/_form.html.erb

@@ -1,11 +1,26 @@
-<%= form.hidden_field :id %>
-<div class="nested-form-wrapper" data-new-record="<%= form.object.new_record? %>">
-  <%= form.input mythology_id, collection: @mythologies, label_method: :name, value_method: :id,
-      default: @mythologies.first,
-      input_html: { class: 'rounded', style: 'margin-left: 62px;' } %>
-  <%= f.input :description,
-      input_html: { class: 'rounded mt-5', style: 'margin-left: 7px;' } %>
+<%= simple_form_for @mythology do |f| %>
+  <% if @mythology.errors.any? %>
+    <div id="error_explanation">
+      <h2><%= pluralize(@mythology.errors.count, "error") %> prohibited this mythology from being saved:</h2>
+      <ul>
+        <% @mythology.errors.full_messages.each do |msg| %>
+          <li><%= msg %></li>
+        <% end %>
+      </ul>
+    </div>
+  <% end %>
 
-  <button type="button" data-action="nested-form#remove">Remove mythology</button>
-  <%= form.hidden_field :_destroy %>
-</div>
+  <div class="field">
+    <%= f.label :name %>
+    <%= f.text_field :name %>
+  </div>
+
+  <div class="field">
+    <%= f.label :description %>
+    <%= f.text_area :description %>
+  </div>
+
+  <div class="actions">
+    <%= f.submit "Save Mythology" %>
+  </div>
+<% end %>

app/views/mythologies/index.html.erb

@@ -22,3 +22,5 @@
             class: "px-4 py-4 bg-green-500 hover:bg-green-700 rounded" %>
 <%= link_to "List of Stories", stories_path, id: "stories",
             class: "px-4 py-4 bg-green-500 hover:bg-green-700 rounded" %>
+<%= link_to "New Mythology", new_mythology_path, 
+            class: "px-4 py-4 bg-green-500 hover:bg-green-700 rounded" %>

config/routes.rb

@@ -11,6 +11,7 @@
     # TODO:
     # https://dev.to/pezza/dynamic-nested-forms-with-turbo-3786
   end
+  resources :mythologies, only: [:index, :new, :create]
   # Defines the root path route ("/")
   root "mythologies#index"
 end