{-# LANGUAGE DeriveGeneric #-}
{-# LANGUAGE DuplicateRecordFields #-}
{-# LANGUAGE NamedFieldPuns #-}
{-# LANGUAGE OverloadedStrings #-}
{-# LANGUAGE RecordWildCards #-}
{-# LANGUAGE StrictData #-}
{-# LANGUAGE TypeFamilies #-}
{-# LANGUAGE NoImplicitPrelude #-}
{-# OPTIONS_GHC -fno-warn-unused-binds #-}
{-# OPTIONS_GHC -fno-warn-unused-imports #-}
{-# OPTIONS_GHC -fno-warn-unused-matches #-}

-- Derived from AWS service descriptions, licensed under Apache 2.0.

-- |
-- Module      : Amazonka.AutoScaling.DetachInstances
-- Copyright   : (c) 2013-2023 Brendan Hay
-- License     : Mozilla Public License, v. 2.0.
-- Maintainer  : Brendan Hay
-- Stability   : auto-generated
-- Portability : non-portable (GHC extensions)
--
-- Removes one or more instances from the specified Auto Scaling group.
--
-- After the instances are detached, you can manage them independent of the
-- Auto Scaling group.
--
-- If you do not specify the option to decrement the desired capacity,
-- Amazon EC2 Auto Scaling launches instances to replace the ones that are
-- detached.
--
-- If there is a Classic Load Balancer attached to the Auto Scaling group,
-- the instances are deregistered from the load balancer. If there are
-- target groups attached to the Auto Scaling group, the instances are
-- deregistered from the target groups.
--
-- For more information, see
-- <https://docs.aws.amazon.com/autoscaling/ec2/userguide/detach-instance-asg.html Detach EC2 instances from your Auto Scaling group>
-- in the /Amazon EC2 Auto Scaling User Guide/.
module Amazonka.AutoScaling.DetachInstances
  ( -- * Creating a Request
    DetachInstances (..),
    newDetachInstances,

    -- * Request Lenses
    detachInstances_instanceIds,
    detachInstances_autoScalingGroupName,
    detachInstances_shouldDecrementDesiredCapacity,

    -- * Destructuring the Response
    DetachInstancesResponse (..),
    newDetachInstancesResponse,

    -- * Response Lenses
    detachInstancesResponse_activities,
    detachInstancesResponse_httpStatus,
  )
where

import Amazonka.AutoScaling.Types
import qualified Amazonka.Core as Core
import qualified Amazonka.Core.Lens.Internal as Lens
import qualified Amazonka.Data as Data
import qualified Amazonka.Prelude as Prelude
import qualified Amazonka.Request as Request
import qualified Amazonka.Response as Response

-- | /See:/ 'newDetachInstances' smart constructor.
data DetachInstances = DetachInstances'
  { -- | The IDs of the instances. You can specify up to 20 instances.
    instanceIds :: Prelude.Maybe [Prelude.Text],
    -- | The name of the Auto Scaling group.
    autoScalingGroupName :: Prelude.Text,
    -- | Indicates whether the Auto Scaling group decrements the desired capacity
    -- value by the number of instances detached.
    shouldDecrementDesiredCapacity :: Prelude.Bool
  }
  deriving (Prelude.Eq, Prelude.Read, Prelude.Show, Prelude.Generic)

-- |
-- Create a value of 'DetachInstances' with all optional fields omitted.
--
-- Use <https://hackage.haskell.org/package/generic-lens generic-lens> or <https://hackage.haskell.org/package/optics optics> to modify other optional fields.
--
-- The following record fields are available, with the corresponding lenses provided
-- for backwards compatibility:
--
-- 'instanceIds', 'detachInstances_instanceIds' - The IDs of the instances. You can specify up to 20 instances.
--
-- 'autoScalingGroupName', 'detachInstances_autoScalingGroupName' - The name of the Auto Scaling group.
--
-- 'shouldDecrementDesiredCapacity', 'detachInstances_shouldDecrementDesiredCapacity' - Indicates whether the Auto Scaling group decrements the desired capacity
-- value by the number of instances detached.
newDetachInstances ::
  -- | 'autoScalingGroupName'
  Prelude.Text ->
  -- | 'shouldDecrementDesiredCapacity'
  Prelude.Bool ->
  DetachInstances
newDetachInstances
  pAutoScalingGroupName_
  pShouldDecrementDesiredCapacity_ =
    DetachInstances'
      { instanceIds = Prelude.Nothing,
        autoScalingGroupName = pAutoScalingGroupName_,
        shouldDecrementDesiredCapacity =
          pShouldDecrementDesiredCapacity_
      }

-- | The IDs of the instances. You can specify up to 20 instances.
detachInstances_instanceIds :: Lens.Lens' DetachInstances (Prelude.Maybe [Prelude.Text])
detachInstances_instanceIds = Lens.lens (\DetachInstances' {instanceIds} -> instanceIds) (\s@DetachInstances' {} a -> s {instanceIds = a} :: DetachInstances) Prelude.. Lens.mapping Lens.coerced

-- | The name of the Auto Scaling group.
detachInstances_autoScalingGroupName :: Lens.Lens' DetachInstances Prelude.Text
detachInstances_autoScalingGroupName = Lens.lens (\DetachInstances' {autoScalingGroupName} -> autoScalingGroupName) (\s@DetachInstances' {} a -> s {autoScalingGroupName = a} :: DetachInstances)

-- | Indicates whether the Auto Scaling group decrements the desired capacity
-- value by the number of instances detached.
detachInstances_shouldDecrementDesiredCapacity :: Lens.Lens' DetachInstances Prelude.Bool
detachInstances_shouldDecrementDesiredCapacity = Lens.lens (\DetachInstances' {shouldDecrementDesiredCapacity} -> shouldDecrementDesiredCapacity) (\s@DetachInstances' {} a -> s {shouldDecrementDesiredCapacity = a} :: DetachInstances)

instance Core.AWSRequest DetachInstances where
  type
    AWSResponse DetachInstances =
      DetachInstancesResponse
  request overrides =
    Request.postQuery (overrides defaultService)
  response =
    Response.receiveXMLWrapper
      "DetachInstancesResult"
      ( \s h x ->
          DetachInstancesResponse'
            Prelude.<$> ( x
                            Data..@? "Activities"
                            Core..!@ Prelude.mempty
                            Prelude.>>= Core.may (Data.parseXMLList "member")
                        )
            Prelude.<*> (Prelude.pure (Prelude.fromEnum s))
      )

instance Prelude.Hashable DetachInstances where
  hashWithSalt _salt DetachInstances' {..} =
    _salt
      `Prelude.hashWithSalt` instanceIds
      `Prelude.hashWithSalt` autoScalingGroupName
      `Prelude.hashWithSalt` shouldDecrementDesiredCapacity

instance Prelude.NFData DetachInstances where
  rnf DetachInstances' {..} =
    Prelude.rnf instanceIds
      `Prelude.seq` Prelude.rnf autoScalingGroupName
      `Prelude.seq` Prelude.rnf shouldDecrementDesiredCapacity

instance Data.ToHeaders DetachInstances where
  toHeaders = Prelude.const Prelude.mempty

instance Data.ToPath DetachInstances where
  toPath = Prelude.const "/"

instance Data.ToQuery DetachInstances where
  toQuery DetachInstances' {..} =
    Prelude.mconcat
      [ "Action"
          Data.=: ("DetachInstances" :: Prelude.ByteString),
        "Version"
          Data.=: ("2011-01-01" :: Prelude.ByteString),
        "InstanceIds"
          Data.=: Data.toQuery
            (Data.toQueryList "member" Prelude.<$> instanceIds),
        "AutoScalingGroupName" Data.=: autoScalingGroupName,
        "ShouldDecrementDesiredCapacity"
          Data.=: shouldDecrementDesiredCapacity
      ]

-- | /See:/ 'newDetachInstancesResponse' smart constructor.
data DetachInstancesResponse = DetachInstancesResponse'
  { -- | The activities related to detaching the instances from the Auto Scaling
    -- group.
    activities :: Prelude.Maybe [Activity],
    -- | The response's http status code.
    httpStatus :: Prelude.Int
  }
  deriving (Prelude.Eq, Prelude.Read, Prelude.Show, Prelude.Generic)

-- |
-- Create a value of 'DetachInstancesResponse' with all optional fields omitted.
--
-- Use <https://hackage.haskell.org/package/generic-lens generic-lens> or <https://hackage.haskell.org/package/optics optics> to modify other optional fields.
--
-- The following record fields are available, with the corresponding lenses provided
-- for backwards compatibility:
--
-- 'activities', 'detachInstancesResponse_activities' - The activities related to detaching the instances from the Auto Scaling
-- group.
--
-- 'httpStatus', 'detachInstancesResponse_httpStatus' - The response's http status code.
newDetachInstancesResponse ::
  -- | 'httpStatus'
  Prelude.Int ->
  DetachInstancesResponse
newDetachInstancesResponse pHttpStatus_ =
  DetachInstancesResponse'
    { activities =
        Prelude.Nothing,
      httpStatus = pHttpStatus_
    }

-- | The activities related to detaching the instances from the Auto Scaling
-- group.
detachInstancesResponse_activities :: Lens.Lens' DetachInstancesResponse (Prelude.Maybe [Activity])
detachInstancesResponse_activities = Lens.lens (\DetachInstancesResponse' {activities} -> activities) (\s@DetachInstancesResponse' {} a -> s {activities = a} :: DetachInstancesResponse) Prelude.. Lens.mapping Lens.coerced

-- | The response's http status code.
detachInstancesResponse_httpStatus :: Lens.Lens' DetachInstancesResponse Prelude.Int
detachInstancesResponse_httpStatus = Lens.lens (\DetachInstancesResponse' {httpStatus} -> httpStatus) (\s@DetachInstancesResponse' {} a -> s {httpStatus = a} :: DetachInstancesResponse)

instance Prelude.NFData DetachInstancesResponse where
  rnf DetachInstancesResponse' {..} =
    Prelude.rnf activities
      `Prelude.seq` Prelude.rnf httpStatus