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

/**
 * Splitting equal-sized obfuscated volumes (CONCEPT.md D20): the extra
 * articles of conflicted binaries are kept, and the split-off volumes point
 * to the conflicted binary they came from.
 */
export default class extends BaseSchema {
  async up() {
    this.schema.createTable('part_conflicts', (table) => {
      table.bigInteger('binary_id').notNullable().references('binaries.id').onDelete('CASCADE')
      table.integer('number').notNullable()
      table.text('message_id').notNullable()
      table.integer('bytes').notNullable()
      table.bigInteger('article_number')
      table.primary(['binary_id', 'number', 'message_id'])
    })
    this.schema.alterTable('binaries', (table) => {
      table.bigInteger('parent_binary_id').references('binaries.id').onDelete('SET NULL').index()
      // Last time the splitter processed this conflicted binary.
      table.timestamp('split_at', { useTz: true })
    })
  }

  async down() {
    this.schema.alterTable('binaries', (table) => {
      table.dropColumn('split_at')
      table.dropColumn('parent_binary_id')
    })
    this.schema.dropTable('part_conflicts')
  }
}