Add more detailed zone occupy info to simplified item preview page

Adapting what the Impress 2020 UI does, but in Ruby instead!

I feel like this is case is really starting to show the power of doing
this stuff in Rails instead of via an API… we can *really* take
advantage of our models and our handy idioms at all points. This is
just so much less *code* than this feature takes in Node + GraphQL +
React.

app/assets/stylesheets/items/_show.sass

@@ -183,3 +183,7 @@ body.items-show
     .no-zones
       font-style: italic
       opacity: .85
+
+    .zone-species-info
+      font-style: italic
+      text-decoration: underline dotted

app/controllers/items_controller.rb

@@ -89,6 +89,10 @@ class ItemsController < ApplicationController
           worn_items: [@item],
         )
         @preview_error = validate_preview
+
+        @all_appearances = @item.appearances
+        @appearances_by_occupied_zone = @item.appearances_by_occupied_zone.
+          sort_by { |z, a| z.label }
       end
 
       format.gif do

app/helpers/items_helper.rb

@@ -222,6 +222,14 @@ module ItemsHelper
     cookies["DTIOutfitViewerIsPlaying"] == "true"
   end
 
+  def item_zone_partial_fit?(appearances_in_zone, all_appearances)
+    appearances_in_zone.size < all_appearances.size
+  end
+
+  def item_zone_species_list(appearances_in_zone)
+    appearances_in_zone.map(&:species).uniq.map(&:human_name).sort.join(", ")
+  end
+
   private
 
   def pet_type_image(pet_type, emotion, size)

app/models/item.rb

@@ -502,11 +502,16 @@ class Item < ApplicationRecord
   Appearance = Struct.new(:item, :body, :swf_assets) do
     include ActiveModel::Serializers::JSON
     delegate :present?, :empty?, to: :swf_assets
+    delegate :species, to: :body
 
     def attributes
       {item:, body:, swf_assets:}
     end
 
+    def occupied_zone_ids
+      swf_assets.map(&:zone_id).uniq.sort
+    end
+
     def restricted_zone_ids
       return [] if empty?
       ([item] + swf_assets).map(&:restricted_zone_ids).flatten.uniq.sort
@@ -550,6 +555,22 @@ class Item < ApplicationRecord
     Item.appearances_for([self], target, ...)[id]
   end
 
+  def appearances_by_occupied_zone_id
+    {}.tap do |h|
+      appearances.each do |appearance|
+        appearance.occupied_zone_ids.each do |zone_id|
+          h[zone_id] ||= []
+          h[zone_id] << appearance
+        end
+      end
+    end
+  end
+
+  def appearances_by_occupied_zone
+    zones_by_id = occupied_zones.to_h { |z| [z.id, z] }
+    appearances_by_occupied_zone_id.transform_keys { |zid| zones_by_id[zid] }
+  end
+
   # Given a list of items, return how they look on the given target (either a
   # pet type or an alt style).
   def self.appearances_for(items, target, swf_asset_includes: [])

app/views/items/show.html.haml

@@ -36,10 +36,16 @@
   .item-zones-info
     %section
       %h3 Occupies
-      - if @item.occupied_zones.present?
+      - if @appearances_by_occupied_zone.present?
         %ul
-          - @item.occupied_zones.sort_by(&:label).each do |zone|
+          - @appearances_by_occupied_zone.each do |zone, appearances_in_zone|
-            %li= zone.label
+            %li
+              = zone.label
+              - if item_zone_partial_fit? appearances_in_zone, @all_appearances
+                %span.zone-species-info{
+                  title: item_zone_species_list(appearances_in_zone)
+                }
+                  (#{appearances_in_zone.size} species)
       - else
         %span.no-zones (None)