zio_pattern.scala

import zio.{Task, ZIO }

trait ConfigModule {
  def configService: ConfigService

}

trait ConfigService {
  def config: Task[String]
}

trait MetricsModule {
  def metrisService: MetricsService
}

trait MetricsService {
  def metrics: ZIO[ConfigService, Throwable, MicroMeter]
}

case class MicroMeter(s: String) {
  def runMetrics(int: Int): Int = 1
}

trait RepositoryModule {
  def getRepositoryService: RepositoryService
}

trait RepositoryService {
  def repo: Task[Repo]
}

class Repo() {
  def insert(a: Int): Unit = "inserted"
}

object Run {

  val configModule = new ConfigModule {
    override def configService: ConfigService = new ConfigService {
      override def config: Task[String] = ZIO.succeed("this is a config")
    }
  }

  val metricsService = new MetricsModule {
    override def metrisService: MetricsService = new MetricsService {
      override def metrics: ZIO[ConfigService, Throwable, MicroMeter] =
        ZIO.accessM(config => config.config.map(s => MicroMeter(s)))
    }
  }

  val repositoryModule = new RepositoryModule {
    override def getRepositoryService: RepositoryService = new RepositoryService {
      override def repo: Task[Repo] = ZIO.succeed(new Repo)
    }
  }

  type Environment = ConfigModule with MetricsModule with RepositoryModule

  type App = ZIO[Environment, Throwable, ?]

  def mainApp: ZIO[RepositoryService with MetricsService with ConfigService, Throwable, Unit] =
    for {
      integer <- ZIO.accessM[MetricsService with ConfigService](_.metrics.map(_.runMetrics(1)))
      _ <- ZIO.accessM[RepositoryService](_.repo.map(_.insert(integer)))
    } yield ()
}