ugoira: remove the PixivUgoiraFrameData model.

Remove the last remaining uses of the PixivUgoiraFrameData model. As of
32bfb8407, Ugoira frame data is now stored in the MediaMetadata model,
under the `Ugoira:FrameDelays` EXIF field.

The pixiv_ugoira_frame_data table still exists, but it can be removed
after this commit is deployed.

Fixes #5264: Error when replacing with ugoira.

app/models/media_asset.rb

@@ -17,13 +17,12 @@ class MediaAsset < ApplicationRecord
 
   has_one :post, foreign_key: :md5, primary_key: :md5
   has_one :media_metadata, dependent: :destroy
-  has_one :pixiv_ugoira_frame_data, class_name: "PixivUgoiraFrameData", foreign_key: :md5, primary_key: :md5
   has_many :upload_media_assets, dependent: :destroy
   has_many :uploads, through: :upload_media_assets
   has_many :uploaders, through: :uploads, class_name: "User", foreign_key: :uploader_id
   has_many :ai_tags
 
-  delegate :metadata, to: :media_metadata
+  delegate :frame_delays, :metadata, to: :media_metadata
   delegate :is_non_repeating_animation?, :is_greyscale?, :is_rotated?, :is_ai_generated?, to: :metadata
 
   scope :public_only, -> { where(is_public: true) }
@@ -81,8 +80,8 @@ class MediaAsset < ApplicationRecord
 
     def open_file
       file = storage_service.open(file_path)
-      frame_data = media_asset.pixiv_ugoira_frame_data&.data if media_asset.is_ugoira?
-      MediaFile.open(file, frame_data: frame_data, strict: false)
+      frame_delays = media_asset.frame_delays if media_asset.is_ugoira?
+      MediaFile.open(file, frame_delays: frame_delays, strict: false)
     end
 
     def convert_file(media_file)
@@ -252,7 +251,6 @@ class MediaAsset < ApplicationRecord
         # XXX should do this in parallel with thumbnail generation.
         # XXX shouldn't generate thumbnail twice (very slow for ugoira)
         media_asset.update!(ai_tags: media_file.preview(360, 360).ai_tags)
-        media_asset.update!(pixiv_ugoira_frame_data: PixivUgoiraFrameData.new(data: media_file.frame_data, content_type: "image/jpeg")) if media_asset.is_ugoira?
         media_asset.update!(media_metadata: MediaMetadata.new(file: media_file))
 
         media_asset.distribute_files!(media_file)
@@ -423,6 +421,6 @@ class MediaAsset < ApplicationRecord
   end
 
   def self.available_includes
-    %i[post media_metadata pixiv_ugoira_frame_data ai_tags]
+    %i[post media_metadata ai_tags]
   end
 end

app/models/media_metadata.rb

@@ -28,4 +28,8 @@ class MediaMetadata < ApplicationRecord
   def metadata
     ExifTool::Metadata.new(self[:metadata])
   end
+
+  def frame_delays
+    metadata["Ugoira:FrameDelays"].to_a
+  end
 end

app/models/pixiv_ugoira_frame_data.rb

@@ -1,33 +0,0 @@
-# frozen_string_literal: true
-
-class PixivUgoiraFrameData < ApplicationRecord
-  belongs_to :post, optional: true, foreign_key: :md5, primary_key: :md5
-  belongs_to :media_asset, foreign_key: :md5, primary_key: :md5
-
-  serialize :data
-  before_validation :normalize_data, on: :create
-
-  def self.available_includes
-    [:post]
-  end
-
-  def self.search(params, current_user)
-    q = search_attributes(params, [:id, :data, :content_type, :post, :md5], current_user: current_user)
-    q.apply_default_order(params)
-  end
-
-  def frame_delays
-    data.pluck("delay")
-  end
-
-  def normalize_data
-    return if data.nil?
-
-    if data[0]["delay_msec"]
-      self.data = data.map.with_index do |datum, i|
-        filename = format("%06d.jpg", i)
-        {"delay" => datum["delay_msec"], "file" => filename}
-      end
-    end
-  end
-end

app/models/post.rb

@@ -58,7 +58,6 @@ class Post < ApplicationRecord
   has_one :media_asset, -> { active }, foreign_key: :md5, primary_key: :md5
   has_one :media_metadata, through: :media_asset
   has_one :artist_commentary, :dependent => :destroy
-  has_one :pixiv_ugoira_frame_data, class_name: "PixivUgoiraFrameData", foreign_key: :md5, primary_key: :md5
   has_one :vote_by_current_user, -> { active.where(user_id: CurrentUser.id) }, class_name: "PostVote" # XXX using current user here is wrong
   has_many :flags, :class_name => "PostFlag", :dependent => :destroy
   has_many :appeals, :class_name => "PostAppeal", :dependent => :destroy
@@ -1406,7 +1405,7 @@ class Post < ApplicationRecord
           :last_comment_bumped_at, :last_commented_at, :last_noted_at,
           :uploader, :approver, :parent,
           :artist_commentary, :flags, :appeals, :notes, :comments, :children,
-          :approvals, :replacements, :pixiv_ugoira_frame_data],
+          :approvals, :replacements],
           current_user: current_user
         )
 
@@ -1630,7 +1629,7 @@ class Post < ApplicationRecord
     # attributes accessible through the ?only= parameter
     %i[
       uploader approver flags appeals events parent children notes
-      comments approvals disapprovals replacements pixiv_ugoira_frame_data
+      comments approvals disapprovals replacements
       artist_commentary media_asset ai_tags
     ]
   end