{-# 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.ECS.ListClusters
-- Copyright   : (c) 2013-2023 Brendan Hay
-- License     : Mozilla Public License, v. 2.0.
-- Maintainer  : Brendan Hay
-- Stability   : auto-generated
-- Portability : non-portable (GHC extensions)
--
-- Returns a list of existing clusters.
--
-- This operation returns paginated results.
module Amazonka.ECS.ListClusters
  ( -- * Creating a Request
    ListClusters (..),
    newListClusters,

    -- * Request Lenses
    listClusters_maxResults,
    listClusters_nextToken,

    -- * Destructuring the Response
    ListClustersResponse (..),
    newListClustersResponse,

    -- * Response Lenses
    listClustersResponse_clusterArns,
    listClustersResponse_nextToken,
    listClustersResponse_httpStatus,
  )
where

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

-- | /See:/ 'newListClusters' smart constructor.
data ListClusters = ListClusters'
  { -- | The maximum number of cluster results that @ListClusters@ returned in
    -- paginated output. When this parameter is used, @ListClusters@ only
    -- returns @maxResults@ results in a single page along with a @nextToken@
    -- response element. The remaining results of the initial request can be
    -- seen by sending another @ListClusters@ request with the returned
    -- @nextToken@ value. This value can be between 1 and 100. If this
    -- parameter isn\'t used, then @ListClusters@ returns up to 100 results and
    -- a @nextToken@ value if applicable.
    maxResults :: Prelude.Maybe Prelude.Int,
    -- | The @nextToken@ value returned from a @ListClusters@ request indicating
    -- that more results are available to fulfill the request and further calls
    -- are needed. If @maxResults@ was provided, it\'s possible the number of
    -- results to be fewer than @maxResults@.
    --
    -- This token should be treated as an opaque identifier that is only used
    -- to retrieve the next items in a list and not for other programmatic
    -- purposes.
    nextToken :: Prelude.Maybe Prelude.Text
  }
  deriving (Prelude.Eq, Prelude.Read, Prelude.Show, Prelude.Generic)

-- |
-- Create a value of 'ListClusters' 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:
--
-- 'maxResults', 'listClusters_maxResults' - The maximum number of cluster results that @ListClusters@ returned in
-- paginated output. When this parameter is used, @ListClusters@ only
-- returns @maxResults@ results in a single page along with a @nextToken@
-- response element. The remaining results of the initial request can be
-- seen by sending another @ListClusters@ request with the returned
-- @nextToken@ value. This value can be between 1 and 100. If this
-- parameter isn\'t used, then @ListClusters@ returns up to 100 results and
-- a @nextToken@ value if applicable.
--
-- 'nextToken', 'listClusters_nextToken' - The @nextToken@ value returned from a @ListClusters@ request indicating
-- that more results are available to fulfill the request and further calls
-- are needed. If @maxResults@ was provided, it\'s possible the number of
-- results to be fewer than @maxResults@.
--
-- This token should be treated as an opaque identifier that is only used
-- to retrieve the next items in a list and not for other programmatic
-- purposes.
newListClusters ::
  ListClusters
newListClusters =
  ListClusters'
    { maxResults = Prelude.Nothing,
      nextToken = Prelude.Nothing
    }

-- | The maximum number of cluster results that @ListClusters@ returned in
-- paginated output. When this parameter is used, @ListClusters@ only
-- returns @maxResults@ results in a single page along with a @nextToken@
-- response element. The remaining results of the initial request can be
-- seen by sending another @ListClusters@ request with the returned
-- @nextToken@ value. This value can be between 1 and 100. If this
-- parameter isn\'t used, then @ListClusters@ returns up to 100 results and
-- a @nextToken@ value if applicable.
listClusters_maxResults :: Lens.Lens' ListClusters (Prelude.Maybe Prelude.Int)
listClusters_maxResults = Lens.lens (\ListClusters' {maxResults} -> maxResults) (\s@ListClusters' {} a -> s {maxResults = a} :: ListClusters)

-- | The @nextToken@ value returned from a @ListClusters@ request indicating
-- that more results are available to fulfill the request and further calls
-- are needed. If @maxResults@ was provided, it\'s possible the number of
-- results to be fewer than @maxResults@.
--
-- This token should be treated as an opaque identifier that is only used
-- to retrieve the next items in a list and not for other programmatic
-- purposes.
listClusters_nextToken :: Lens.Lens' ListClusters (Prelude.Maybe Prelude.Text)
listClusters_nextToken = Lens.lens (\ListClusters' {nextToken} -> nextToken) (\s@ListClusters' {} a -> s {nextToken = a} :: ListClusters)

instance Core.AWSPager ListClusters where
  page rq rs
    | Core.stop
        ( rs
            Lens.^? listClustersResponse_nextToken
            Prelude.. Lens._Just
        ) =
        Prelude.Nothing
    | Core.stop
        ( rs
            Lens.^? listClustersResponse_clusterArns
            Prelude.. Lens._Just
        ) =
        Prelude.Nothing
    | Prelude.otherwise =
        Prelude.Just
          Prelude.$ rq
          Prelude.& listClusters_nextToken
          Lens..~ rs
          Lens.^? listClustersResponse_nextToken
          Prelude.. Lens._Just

instance Core.AWSRequest ListClusters where
  type AWSResponse ListClusters = ListClustersResponse
  request overrides =
    Request.postJSON (overrides defaultService)
  response =
    Response.receiveJSON
      ( \s h x ->
          ListClustersResponse'
            Prelude.<$> (x Data..?> "clusterArns" Core..!@ Prelude.mempty)
            Prelude.<*> (x Data..?> "nextToken")
            Prelude.<*> (Prelude.pure (Prelude.fromEnum s))
      )

instance Prelude.Hashable ListClusters where
  hashWithSalt _salt ListClusters' {..} =
    _salt
      `Prelude.hashWithSalt` maxResults
      `Prelude.hashWithSalt` nextToken

instance Prelude.NFData ListClusters where
  rnf ListClusters' {..} =
    Prelude.rnf maxResults
      `Prelude.seq` Prelude.rnf nextToken

instance Data.ToHeaders ListClusters where
  toHeaders =
    Prelude.const
      ( Prelude.mconcat
          [ "X-Amz-Target"
              Data.=# ( "AmazonEC2ContainerServiceV20141113.ListClusters" ::
                          Prelude.ByteString
                      ),
            "Content-Type"
              Data.=# ( "application/x-amz-json-1.1" ::
                          Prelude.ByteString
                      )
          ]
      )

instance Data.ToJSON ListClusters where
  toJSON ListClusters' {..} =
    Data.object
      ( Prelude.catMaybes
          [ ("maxResults" Data..=) Prelude.<$> maxResults,
            ("nextToken" Data..=) Prelude.<$> nextToken
          ]
      )

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

instance Data.ToQuery ListClusters where
  toQuery = Prelude.const Prelude.mempty

-- | /See:/ 'newListClustersResponse' smart constructor.
data ListClustersResponse = ListClustersResponse'
  { -- | The list of full Amazon Resource Name (ARN) entries for each cluster
    -- that\'s associated with your account.
    clusterArns :: Prelude.Maybe [Prelude.Text],
    -- | The @nextToken@ value to include in a future @ListClusters@ request.
    -- When the results of a @ListClusters@ request exceed @maxResults@, this
    -- value can be used to retrieve the next page of results. This value is
    -- @null@ when there are no more results to return.
    nextToken :: Prelude.Maybe Prelude.Text,
    -- | The response's http status code.
    httpStatus :: Prelude.Int
  }
  deriving (Prelude.Eq, Prelude.Read, Prelude.Show, Prelude.Generic)

-- |
-- Create a value of 'ListClustersResponse' 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:
--
-- 'clusterArns', 'listClustersResponse_clusterArns' - The list of full Amazon Resource Name (ARN) entries for each cluster
-- that\'s associated with your account.
--
-- 'nextToken', 'listClustersResponse_nextToken' - The @nextToken@ value to include in a future @ListClusters@ request.
-- When the results of a @ListClusters@ request exceed @maxResults@, this
-- value can be used to retrieve the next page of results. This value is
-- @null@ when there are no more results to return.
--
-- 'httpStatus', 'listClustersResponse_httpStatus' - The response's http status code.
newListClustersResponse ::
  -- | 'httpStatus'
  Prelude.Int ->
  ListClustersResponse
newListClustersResponse pHttpStatus_ =
  ListClustersResponse'
    { clusterArns =
        Prelude.Nothing,
      nextToken = Prelude.Nothing,
      httpStatus = pHttpStatus_
    }

-- | The list of full Amazon Resource Name (ARN) entries for each cluster
-- that\'s associated with your account.
listClustersResponse_clusterArns :: Lens.Lens' ListClustersResponse (Prelude.Maybe [Prelude.Text])
listClustersResponse_clusterArns = Lens.lens (\ListClustersResponse' {clusterArns} -> clusterArns) (\s@ListClustersResponse' {} a -> s {clusterArns = a} :: ListClustersResponse) Prelude.. Lens.mapping Lens.coerced

-- | The @nextToken@ value to include in a future @ListClusters@ request.
-- When the results of a @ListClusters@ request exceed @maxResults@, this
-- value can be used to retrieve the next page of results. This value is
-- @null@ when there are no more results to return.
listClustersResponse_nextToken :: Lens.Lens' ListClustersResponse (Prelude.Maybe Prelude.Text)
listClustersResponse_nextToken = Lens.lens (\ListClustersResponse' {nextToken} -> nextToken) (\s@ListClustersResponse' {} a -> s {nextToken = a} :: ListClustersResponse)

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

instance Prelude.NFData ListClustersResponse where
  rnf ListClustersResponse' {..} =
    Prelude.rnf clusterArns
      `Prelude.seq` Prelude.rnf nextToken
      `Prelude.seq` Prelude.rnf httpStatus