Remove "Un-Archive" action, prevent un-archiving

app/models/puzzle.rb

@@ -9,6 +9,8 @@ class Puzzle < ApplicationRecord
 
   scope :archived, -> { where(state: :archived).order(sent_at: :desc) }
 
+  validate :cannot_be_unarchived
+
   def correct_answer_percentage
     total = answers.size
     return 0 if total.zero?
@@ -32,4 +34,10 @@ def self.without_cloned
     cloned_puzzles_ids = unscoped.where.not(original_puzzle_id: nil).pluck(:original_puzzle_id)
     where.not(id: cloned_puzzles_ids)
   end
+
+  private
+
+  def cannot_be_unarchived
+    errors.add(:state, "cannot be unarchived") if state != state_was && state_was == "archived"
+  end
 end

app/views/puzzles/_puzzles_table.html.erb

@@ -43,7 +43,6 @@
             <%= button_to 'Approve', puzzle_state_path(puzzle, state: :approved), method: :patch, form_class: 'inline-form', class: 'btn approve-btn' %>
             <%= button_to 'Pending', puzzle_state_path(puzzle, state: :pending), method: :patch, form_class: 'inline-form', class: 'btn pending-btn' %>
           <% elsif actions == :archived %>
-            <%= button_to 'Un-Archive', puzzle_state_path(puzzle, state: :pending), method: :patch, form_class: 'inline-form', class: 'btn pending-btn' %>
             <%= button_to 'Clone', puzzle_clone_path(puzzle, state: :pending), method: :post, form_class: 'inline-form', class: 'btn pending-btn' %>
           <% end %>
         </td>

test/models/puzzle_test.rb

@@ -81,4 +81,17 @@ class PuzzleTest < ActiveSupport::TestCase
     assert_not_includes puzzles, puzzle3
     assert_includes puzzles, puzzle4
   end
+
+  test "once archived, it cannot be unarchived" do
+    puzzle = puzzles(:archived_low_rate)
+    assert puzzle.valid?
+
+    refute puzzle.update(state: :pending)
+    refute puzzle.update(state: :approved)
+    refute puzzle.update(state: :rejected)
+
+    assert_raises(ActiveRecord::RecordInvalid, match: /State cannot be unarchived/) { puzzle.pending! }
+    assert_raises(ActiveRecord::RecordInvalid, match: /State cannot be unarchived/) { puzzle.approved! }
+    assert_raises(ActiveRecord::RecordInvalid, match: /State cannot be unarchived/) { puzzle.rejected! }
+  end
 end