import { BaseCommand, flags } from '@adonisjs/core/ace'
import { CommandOptions } from '@adonisjs/core/types/ace'
import IndexMaintenance from '#services/IndexMaintenance'

/** Rebuilds bloated indexes online (gc:scheduler also does this weekly). */
export default class DbReindex extends BaseCommand {
  public static commandName = 'db:reindex'
  public static description = 'Rebuilds B-tree indexes that are mostly empty space (online, REINDEX CONCURRENTLY).'

  public static options: CommandOptions = {
    startApp: true,
  }

  @flags.boolean({ description: 'Only show which indexes would be rebuilt' })
  declare dryRun: boolean

  public async run() {
    const rebuilt = await IndexMaintenance.rebuildBloated({ dryRun: this.dryRun })
    const saved = rebuilt.reduce((sum, r) => sum + r.before - r.after, 0)
    this.logger.info(`${rebuilt.length} indexes ${this.dryRun ? 'would be rebuilt' : `rebuilt, ${Math.round(saved / 1024 / 1024)} MB freed`}.`)
  }
}