Get Party ready for preview state

* Added new fields for preview state and generated_at timestamp
* Add preview state enum to model
* Add preview_relevant_changes? after_commit hook

app/models/party.rb

@@ -105,6 +105,15 @@ class Party < ApplicationRecord
 
   attr_accessor :favorited
 
+  self.enum :preview_state, {
+    pending: 0, # Never generated
+    queued: 1, # Generation job scheduled
+    generated: 2, # Has preview image
+    failed: 3 # Generation failed
+  }
+
+  after_commit :schedule_preview_regeneration, if: :preview_relevant_changes?
+
   def is_favorited(user)
     user.favorite_parties.include? self if user
   end
@@ -177,4 +186,18 @@ class Party < ApplicationRecord
 
     errors.add(:guidebooks, 'must be unique')
   end
+
+  def preview_relevant_changes?
+    return false if preview_state == 'queued'
+
+    (saved_changes.keys & %w[name job_id element weapons_count characters_count summons_count]).any?
+  end
+
+  def schedule_preview_regeneration
+    # Cancel any pending jobs
+    GeneratePartyPreviewJob.cancel_scheduled_jobs(party_id: id)
+
+    # Mark as pending
+    update_column(:preview_state, :pending)
+  end
 end

db/migrate/20250118135254_add_preview_columns_to_parties.rb

@@ -0,0 +1,9 @@
+class AddPreviewColumnsToParties < ActiveRecord::Migration[8.0]
+  def change
+    add_column :parties, :preview_state, :integer, default: 0, null: false
+    add_column :parties, :preview_generated_at, :datetime
+
+    add_index :parties, :preview_state
+    add_index :parties, :preview_generated_at
+  end
+end

db/schema.rb

@@ -10,12 +10,12 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema[7.0].define(version: 2025_01_15_100356) do
+ActiveRecord::Schema[8.0].define(version: 2025_01_18_135254) do
   # These are extensions that must be enabled in order to support this database
   enable_extension "btree_gin"
+  enable_extension "pg_catalog.plpgsql"
   enable_extension "pg_trgm"
   enable_extension "pgcrypto"
-  enable_extension "plpgsql"
   enable_extension "uuid-ossp"
 
   create_table "app_updates", primary_key: "updated_at", id: :datetime, force: :cascade do |t|
@@ -300,11 +300,15 @@ ActiveRecord::Schema[7.0].define(version: 2025_01_15_100356) do
     t.boolean "auto_summon", default: false
     t.boolean "remix", default: false, null: false
     t.integer "visibility", default: 1, null: false
+    t.integer "preview_state", default: 0, null: false
+    t.datetime "preview_generated_at"
     t.index ["accessory_id"], name: "index_parties_on_accessory_id"
     t.index ["guidebook1_id"], name: "index_parties_on_guidebook1_id"
     t.index ["guidebook2_id"], name: "index_parties_on_guidebook2_id"
     t.index ["guidebook3_id"], name: "index_parties_on_guidebook3_id"
     t.index ["job_id"], name: "index_parties_on_job_id"
+    t.index ["preview_generated_at"], name: "index_parties_on_preview_generated_at"
+    t.index ["preview_state"], name: "index_parties_on_preview_state"
     t.index ["skill0_id"], name: "index_parties_on_skill0_id"
     t.index ["skill1_id"], name: "index_parties_on_skill1_id"
     t.index ["skill2_id"], name: "index_parties_on_skill2_id"