import type {
  GameState,
  SaveMigrationManifest,
} from '../../types';
import { createEmptyStoryEngineMemoryState } from './visibilityEngine';

export function buildSaveMigrationManifest(params: {
  version: string;
}) {
  return {
    version: params.version,
    requiredTransforms: [
      'ensure_story_engine_memory',
      'ensure_campaign_state',
      'ensure_player_style_profile',
    ],
    backwardCompatible: true,
  } satisfies SaveMigrationManifest;
}

export function applyStoryEngineMigration(params: {
  state: GameState;
  manifest: SaveMigrationManifest;
}) {
  const storyEngineMemory =
    params.state.storyEngineMemory ?? createEmptyStoryEngineMemoryState();

  return {
    ...params.state,
    storyEngineMemory: {
      ...createEmptyStoryEngineMemoryState(),
      ...storyEngineMemory,
      saveMigrationManifest: params.manifest,
    },
  };
}