import { MongoMigration } from '../mongo_migrator.js'

export default class CreateCwmpExchangesCollection extends MongoMigration {
  async up(): Promise<void> {
    const exchanges = this.db.collection('cwmp_exchanges')

    // Compound index for efficient retrieval by device, ordered by time
    await exchanges.createIndex(
      { deviceId: 1, timestamp: 1 },
      { name: 'idx_deviceId_timestamp' }
    )

    // Unique index for atomic sequence numbering and Last-Event-ID queries
    await exchanges.createIndex(
      { deviceId: 1, sequenceNumber: 1 },
      { unique: true, name: 'idx_deviceId_sequenceNumber' }
    )

    // TTL index to auto-remove exchanges older than 24h
    await exchanges.createIndex(
      { createdAt: 1 },
      { expireAfterSeconds: 86400, name: 'idx_createdAt_ttl' }
    )

    // Create counters collection for atomic sequence number generation
    this.db.collection('cwmp_exchange_counters')
  }

  async down(): Promise<void> {
    await this.db.dropCollection('cwmp_exchanges').catch(() => {})
    await this.db.dropCollection('cwmp_exchange_counters').catch(() => {})
  }
}