Add backend for tips and enable markdown support

app/views/tips/_collapsed_card.html.slim

@@ -13,11 +13,11 @@
     .card-body.p-3
       h5
         = t('exercises.implement.tips.description')
-      = tip.description
+      = render_markdown(tip.description)
       - if tip.example?
-        h5.mt-2
+        h5
           = t('exercises.implement.tips.example')
         pre
-          code.mh-100 class="language-#{tip.file_type.editor_mode.gsub("ace/mode/", "")}"
+          code.mh-100 class="language-#{tip.file_type.programming_language}"
             = tip.example
       = render(partial: 'tips/collapsed_card', collection: exercise_tip.children, as: :exercise_tip)

app/views/tips/_form.html.slim

@@ -0,0 +1,21 @@
+= form_for(@tip, builder: PagedownFormBuilder) do |f|
+  = render('shared/form_errors', object: @tip)
+  .form-group
+    = f.label(:title)
+    = f.text_field(:title, class: 'form-control', required: false)
+  .form-group
+    = f.label(:description)
+    = f.pagedown :description, input_html: { preview: true, rows: 5 }
+  .form-group
+    = f.label(:file_type_id, t('activerecord.attributes.file.file_type_id'))
+    = f.collection_select(:file_type_id, @file_types, :id, :name, {include_blank: true}, class: 'form-control')
+  .form-group
+    = f.label(:example)
+    = f.text_area(:example, class: 'code-field form-control', rows: 5, style: "display:none;", required: false)
+    #editor-edit.original-input data-file-id=@tip.id
+      #frames
+        .edit-frame
+          .editor-content.d-none
+          .editor.allow_ace_tooltip
+  .actions = render('shared/submit_button', f: f, object: @tip)
+  .editor

app/views/tips/edit.html.slim

@@ -0,0 +1,3 @@
+h1 = @tip.to_s
+
+= render('form')

app/views/tips/index.html.slim

@@ -0,0 +1,20 @@
+h1 = Tip.model_name.human(count: 2)
+
+.table-responsive
+  table.sortable.table
+    thead
+      tr
+        th = t('activerecord.attributes.tip.title')
+        th = t('activerecord.attributes.file.file_type')
+        th colspan=3 = t('shared.actions')
+    tbody
+      - @tips.each do |tip|
+        tr
+          td = link_to_if(policy(tip).show?, tip.title || tip.to_s, tip)
+          td = tip.file_type ? link_to_if(policy(tip.file_type).show?, tip.file_type.name, tip.file_type) : ''
+          td = link_to(t('shared.show'), tip) if policy(tip).show?
+          td = link_to(t('shared.edit'), edit_tip_path(tip)) if policy(tip).edit?
+          td = link_to(t('shared.destroy'), tip, data: {confirm: t('shared.confirm_destroy')}, method: :delete) if tip.can_be_destroyed? &&  policy(tip).destroy?
+
+= render('shared/pagination', collection: @tips)
+p = render('shared/new_button', model: Tip, path: new_tip_path)

app/views/tips/new.html.slim

@@ -0,0 +1,3 @@
+h1 = t('shared.new_model', model: Tip.model_name.human)
+
+= render('form')

app/views/tips/show.html.slim

@@ -0,0 +1,17 @@
+- content_for :head do
+  // Force a full page reload, see https://github.com/turbolinks/turbolinks/issues/326.
+     Otherwise, code might not be highlighted correctly (race condition)
+  meta name='turbolinks-visit-control' content='reload'
+  = javascript_pack_tag('highlight', 'data-turbolinks-track': true)
+  = stylesheet_pack_tag('highlight', media: 'all', 'data-turbolinks-track': true)
+
+h1
+  = @tip.to_s
+  = render('shared/edit_button', object: @tip)
+
+= row(label: 'tip.title', value: @tip.title)
+= row(label: 'tip.description', value: render_markdown(@tip.description), class: 'm-0')
+= row(label: 'file.file_type', value: @tip.file_type_id? ? \
+  link_to_if(policy(@tip.file_type).show?, @tip.file_type.name, @tip.file_type) : '')
+= row(label: 'tip.example', value: @tip.file_type_id? ? \
+  code_tag(@tip.example, @tip.file_type.programming_language) : '')