import { BaseSchema } from '@adonisjs/lucid/schema'

/**
 * A second article with the same part CRC is a repost of the same data, not
 * a different file (CONCEPT.md D20). Drop such recorded conflicts and unflag
 * binaries whose only conflicts were reposts. Binaries flagged before CRCs
 * were stored (split_at = 'infinity') cannot be checked and stay flagged.
 */
export default class extends BaseSchema {
  async up() {
    this.defer(async (db) => {
      await db.rawQuery(`
        DELETE FROM part_conflicts c USING parts p
        WHERE p.binary_id = c.binary_id AND p.number = c.number
          AND p.pcrc32 IS NOT NULL AND c.pcrc32 IS NOT NULL AND p.pcrc32 = c.pcrc32`)
      // Split volumes made from reposts are copies of their parent's file.
      await db.rawQuery(`
        DELETE FROM binaries v USING binaries b
        WHERE v.parent_binary_id = b.id AND v.completed_at IS NULL
          AND b.conflicted_at IS NOT NULL AND b.split_at IS DISTINCT FROM 'infinity'
          AND NOT EXISTS (SELECT 1 FROM part_conflicts c WHERE c.binary_id = b.id)`)
      await db.rawQuery(`
        UPDATE binaries b SET conflicted_at = NULL
        WHERE b.conflicted_at IS NOT NULL AND b.parent_binary_id IS NULL
          AND b.split_at IS DISTINCT FROM 'infinity'
          AND NOT EXISTS (SELECT 1 FROM part_conflicts c WHERE c.binary_id = b.id)`)
    })
  }

  async down() {}
}