/*
 * Copyright 2018 Comcast Cable Communications Management, LLC
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package vinyldns.route53.backend

import cats.implicits._
import cats.effect.{ContextShift, IO}
import vinyldns.core.domain.backend.{BackendProvider, BackendProviderConfig, BackendProviderLoader}

class Route53BackendProviderLoader extends BackendProviderLoader {

  private implicit val cs: ContextShift[IO] =
    IO.contextShift(scala.concurrent.ExecutionContext.global)

  /**
    * Loads a backend based on the provided config so that it is ready to use
    * This is internally used typically during startup
    *
    * @param config The BackendConfig, has settings that are specific to this backend
    * @return A ready-to-use Backend instance, or does an IO.raiseError if something bad occurred.
    */
  def load(config: BackendProviderConfig): IO[BackendProvider] =
    Route53ProviderConfig.load(config.settings).flatMap { bec =>
      bec.backends.traverse(Route53Backend.load).map { conns =>
        new Route53BackendProvider(conns)
      }
    }
}
