import { context, locks, logging } from "@budibase/backend-core"
import { LockName, LockType } from "@budibase/types"

import {
  getAppMigrationVersion,
  updateAppMigrationMetadata,
} from "./appMigrationMetadata"
import { AppMigration } from "."

export async function processMigrations(
  appId: string,
  migrations: AppMigration[]
) {
  console.log(`Processing app migration for "${appId}"`)
  // have to wrap in context, this gets the tenant from the app ID
  await context.doInAppContext(appId, async () => {
    await locks.doWithLock(
      {
        name: LockName.APP_MIGRATION,
        type: LockType.AUTO_EXTEND,
        resource: appId,
      },
      async () => {
        try {
          await context.doInAppMigrationContext(appId, async () => {
            let currentVersion = await getAppMigrationVersion(appId)

            const pendingMigrations = migrations
              .filter(m => m.id > currentVersion)
              .sort((a, b) => a.id.localeCompare(b.id))

            const migrationIds = migrations.map(m => m.id).sort()

            let index = 0
            for (const { id, func } of pendingMigrations) {
              const expectedMigration =
                migrationIds[migrationIds.indexOf(currentVersion) + 1]

              if (expectedMigration !== id) {
                throw new Error(
                  `Migration ${id} could not run, update for "${id}" is running but ${expectedMigration} is expected`
                )
              }

              const counter = `(${++index}/${pendingMigrations.length})`
              console.info(`Running migration ${id}... ${counter}`, {
                migrationId: id,
                appId,
              })
              await func()
              await updateAppMigrationMetadata({
                appId,
                version: id,
              })
              currentVersion = id
            }
          })
        } catch (err) {
          logging.logAlert("Failed to run app migration", err)
          throw err
        }
      }
    )

    console.log(`App migration for "${appId}" processed`)
  })
}