import type { FlexStore } from '../ts/classes.flexstore.js';

export interface IFlexProjectionOrderMigrationOptions {
  store: FlexStore;
  storageKeys: Iterable<string>;
}

export class FlexProjectionOrderMigration {
  private readonly store: FlexStore;
  private readonly storageKeys: string[];

  constructor(optionsArg: IFlexProjectionOrderMigrationOptions) {
    this.store = optionsArg.store;
    this.storageKeys = [...new Set(optionsArg.storageKeys)].sort();
  }

  public async run(signalArg?: AbortSignal): Promise<void> {
    for (const storageKey of this.storageKeys) {
      let cursor: Awaited<ReturnType<FlexStore['listProjectionOrderMigrationPage']>>[
        'nextCursor'
      ];
      do {
        signalArg?.throwIfAborted();
        const page = await this.store.listProjectionOrderMigrationPage(storageKey, cursor);
        for (const sessionId of page.sessionIds) {
          signalArg?.throwIfAborted();
          await this.store.rewriteProjectionSourceOrder(storageKey, sessionId);
        }
        cursor = page.nextCursor;
      } while (cursor);
    }
  }
}