Simplify modeling code for biology data

We're leaning more into Rails collection management and autosave stuff!

app/models/pet.rb

@@ -15,41 +15,16 @@ class Pet < ApplicationRecord
     raise UnexpectedDataFormat unless pet_data[:color_id]
     raise UnexpectedDataFormat unless pet_data[:body_id]
 
-    has_alt_style = pet_data[:alt_style].present?
-
-    self.pet_type = PetType.find_or_initialize_by(
-      species_id: pet_data[:species_id].to_i,
-      color_id: pet_data[:color_id].to_i
-    )
+    @pet_state = Pet.pet_state_from_pet_data(pet_data)
+    self.pet_type = @pet_state.pet_type
 
     begin
-      new_image_hash = Neopets::CustomPets.fetch_image_hash(self.name)
+      pet_type.consider_pet_image(name)
     rescue => error
-      Rails.logger.warn "Failed to load image hash: #{error.full_message}"
-    end
-    self.pet_type.image_hash = new_image_hash if new_image_hash.present?
-
-    # With an alt style, `body_id` in the biology data refers to the body ID of
-    # the *alt* style, not the usual pet type. (We have `original_biology` for
-    # *some* of the pet type's situation, but not it's body ID!)
-    #
-    # So, in the alt style case, don't update `body_id` - but if this is our
-    # first time seeing this pet type and it doesn't *have* a `body_id` yet,
-    # let's not be creating it without one. We'll need to model it without the
-    # alt style first. (I don't bother with a clear error message though 😅)
-    self.pet_type.body_id = pet_data[:body_id] unless has_alt_style
-    if self.pet_type.body_id.nil?
-      raise UnexpectedDataFormat,
-        "can't process alt style on first occurrence of pet type"
+      Rails.logger.warn "Failed to load pet image: #{error.full_message}"
     end
 
-    pet_state_biology = has_alt_style ? pet_data[:original_biology] :
-      pet_data[:biology_by_zone]
-    raise UnexpectedDataFormat if pet_state_biology.empty?
-    pet_state_biology[0] = nil # remove effects if present
-    @pet_state = self.pet_type.add_pet_state_from_biology! pet_state_biology
-
-    if has_alt_style
+    if pet_data[:alt_style]
       raise UnexpectedDataFormat unless pet_data[:alt_color]
       raise UnexpectedDataFormat if pet_data[:biology_by_zone].empty?
 
@@ -89,10 +64,7 @@ class Pet < ApplicationRecord
 
   before_validation do
     pet_type.save!
-    if @pet_state
-      @pet_state.save!
-      @pet_state.handle_assets!
-    end
+    @pet_state.save! if @pet_state
 
     if @items
       @items.each do |item|
@@ -112,6 +84,39 @@ class Pet < ApplicationRecord
     pet
   end
 
+  def self.pet_state_from_pet_data(pet_data)
+    # First, set up the pet type.
+    pet_type = PetType.find_or_initialize_by(
+      species_id: pet_data[:species_id],
+      color_id: pet_data[:color_id],
+    )
+
+    # Apply the pet's body ID to the pet type, unless it's wearing an alt
+    # style, in which case ignore it, because it's the *alt style*'s body ID.
+    # (This can theoretically cause a problem saving a new pet type when
+    # there's an alt style too!)
+    pet_type.body_id = pet_data[:body_id] unless pet_data[:alt_style]
+    if pet_type.body_id.nil?
+      raise UnexpectedDataFormat,
+        "can't process alt style on first occurrence of pet type"
+    end
+
+    # Then, set up the biology assets.
+    pet_state_biology = pet_data[:alt_style].present? ?
+      pet_data[:original_biology] :
+      pet_data[:biology_by_zone]
+    body_id = pet_data[:body_id].to_i
+    swf_assets = pet_state_biology.values.map do |biology_data|
+      SwfAsset.from_biology_data(body_id, biology_data)
+    end
+    swf_asset_ids = swf_assets.map(&:remote_id).sort.join(",")
+
+    # Finally, set up the pet state, and use these biology assets.
+    pet_type.pet_states.find_or_initialize_by(swf_asset_ids:).tap do |pet_state|
+      pet_state.swf_assets = swf_assets
+    end
+  end
+
   class UnexpectedDataFormat < RuntimeError;end
 end
 

app/models/pet_state.rb

@@ -6,8 +6,7 @@ class PetState < ApplicationRecord
   has_many :contributions, :as => :contributed,
     :inverse_of => :contributed # in case of duplicates being merged
   has_many :outfits
-  has_many :parent_swf_asset_relationships, :as => :parent,
-    :autosave => false
+  has_many :parent_swf_asset_relationships, :as => :parent
   has_many :swf_assets, :through => :parent_swf_asset_relationships
 
   belongs_to :pet_type
@@ -16,8 +15,6 @@ class PetState < ApplicationRecord
 
   alias_method :swf_asset_ids_from_association, :swf_asset_ids
 
-  attr_writer :parent_swf_asset_relationships_to_update
-
   # A simple ordering that tries to bring reliable pet states to the front.
   scope :emotion_order, -> {
     order(Arel.sql(
@@ -135,71 +132,10 @@ class PetState < ApplicationRecord
     self['swf_asset_ids'] = ids
   end
 
-  def handle_assets!
-    @parent_swf_asset_relationships_to_update.each do |rel|
-      rel.swf_asset.save!
-      rel.save!
-    end
-  end
-
   def to_param
     "#{id}-#{pose.split('_').map(&:capitalize).join('-')}"
   end
 
-  def self.from_pet_type_and_biology_info(pet_type, info)
-    swf_asset_ids = []
-    info.each do |zone_id, asset_info|
-      if zone_id.present? && asset_info
-        swf_asset_ids << asset_info[:part_id].to_i
-      end
-    end
-    swf_asset_ids_str = swf_asset_ids.sort.join(',')
-    if pet_type.new_record?
-      pet_state = self.new :swf_asset_ids => swf_asset_ids_str
-    else
-      pet_state = self.find_or_initialize_by(
-        pet_type_id: pet_type.id,
-        swf_asset_ids: swf_asset_ids_str
-      )
-    end
-    existing_swf_assets = SwfAsset.biology_assets.includes(:zone).
-      where(remote_id: swf_asset_ids)
-    existing_swf_assets_by_id = {}
-    existing_swf_assets.each do |swf_asset|
-      existing_swf_assets_by_id[swf_asset.remote_id] = swf_asset
-    end
-    existing_relationships_by_swf_asset_id = {}
-    unless pet_state.new_record?
-      pet_state.parent_swf_asset_relationships.each do |relationship|
-        existing_relationships_by_swf_asset_id[relationship.swf_asset_id] = relationship
-      end
-    end
-    pet_state.pet_type = pet_type # save the second case from having to look it up by ID
-    relationships = []
-    info.each do |zone_id, asset_info|
-      if zone_id.present? && asset_info
-        swf_asset_id = asset_info[:part_id].to_i
-        swf_asset = existing_swf_assets_by_id[swf_asset_id]
-        unless swf_asset
-          swf_asset = SwfAsset.new
-          swf_asset.remote_id = swf_asset_id
-        end
-        swf_asset.origin_biology_data = asset_info
-        swf_asset.origin_pet_type = pet_type
-        relationship = existing_relationships_by_swf_asset_id[swf_asset.id]
-        unless relationship
-          relationship ||= ParentSwfAssetRelationship.new
-          relationship.parent = pet_state
-          relationship.swf_asset_id = swf_asset.id
-        end
-        relationship.swf_asset = swf_asset
-        relationships << relationship
-      end
-    end
-    pet_state.parent_swf_asset_relationships_to_update = relationships
-    pet_state
-  end
-
   private
 
   # A helper for the `pose=` method.

app/models/pet_type.rb

@@ -57,6 +57,14 @@ class PetType < ApplicationRecord
     basic_image_hash || self['image_hash'] || 'deadbeef'
   end
 
+  def consider_pet_image(pet_name)
+    # If we already have a basic image hash, don't worry about it!
+    return if basic_image_hash?
+
+    # Otherwise, use this as the new image hash for this pet type.
+    self.image_hash = Neopets::CustomPets.fetch_image_hash(pet_name)
+  end
+
   def possibly_new_color
     self.color || Color.new(id: self.color_id)
   end
@@ -71,11 +79,6 @@ class PetType < ApplicationRecord
                    species_human_name: possibly_new_species.human_name)
   end
 
-  def add_pet_state_from_biology!(biology)
-    pet_state = PetState.from_pet_type_and_biology_info(self, biology)
-    pet_state
-  end
-
   def canonical_pet_state
     # For consistency (randomness is always scary!), we use the PetType ID to
     # determine which gender to prefer, if it's not built into the color. That