{-# 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.Rekognition.ListFaces
-- 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 metadata for faces in the specified collection. This metadata
-- includes information such as the bounding box coordinates, the
-- confidence (that the bounding box contains a face), and face ID. For an
-- example, see Listing Faces in a Collection in the Amazon Rekognition
-- Developer Guide.
--
-- This operation requires permissions to perform the
-- @rekognition:ListFaces@ action.
--
-- This operation returns paginated results.
module Amazonka.Rekognition.ListFaces
  ( -- * Creating a Request
    ListFaces (..),
    newListFaces,

    -- * Request Lenses
    listFaces_maxResults,
    listFaces_nextToken,
    listFaces_collectionId,

    -- * Destructuring the Response
    ListFacesResponse (..),
    newListFacesResponse,

    -- * Response Lenses
    listFacesResponse_faceModelVersion,
    listFacesResponse_faces,
    listFacesResponse_nextToken,
    listFacesResponse_httpStatus,
  )
where

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 Amazonka.Rekognition.Types
import qualified Amazonka.Request as Request
import qualified Amazonka.Response as Response

-- | /See:/ 'newListFaces' smart constructor.
data ListFaces = ListFaces'
  { -- | Maximum number of faces to return.
    maxResults :: Prelude.Maybe Prelude.Natural,
    -- | If the previous response was incomplete (because there is more data to
    -- retrieve), Amazon Rekognition returns a pagination token in the
    -- response. You can use this pagination token to retrieve the next set of
    -- faces.
    nextToken :: Prelude.Maybe Prelude.Text,
    -- | ID of the collection from which to list the faces.
    collectionId :: Prelude.Text
  }
  deriving (Prelude.Eq, Prelude.Read, Prelude.Show, Prelude.Generic)

-- |
-- Create a value of 'ListFaces' 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', 'listFaces_maxResults' - Maximum number of faces to return.
--
-- 'nextToken', 'listFaces_nextToken' - If the previous response was incomplete (because there is more data to
-- retrieve), Amazon Rekognition returns a pagination token in the
-- response. You can use this pagination token to retrieve the next set of
-- faces.
--
-- 'collectionId', 'listFaces_collectionId' - ID of the collection from which to list the faces.
newListFaces ::
  -- | 'collectionId'
  Prelude.Text ->
  ListFaces
newListFaces pCollectionId_ =
  ListFaces'
    { maxResults = Prelude.Nothing,
      nextToken = Prelude.Nothing,
      collectionId = pCollectionId_
    }

-- | Maximum number of faces to return.
listFaces_maxResults :: Lens.Lens' ListFaces (Prelude.Maybe Prelude.Natural)
listFaces_maxResults = Lens.lens (\ListFaces' {maxResults} -> maxResults) (\s@ListFaces' {} a -> s {maxResults = a} :: ListFaces)

-- | If the previous response was incomplete (because there is more data to
-- retrieve), Amazon Rekognition returns a pagination token in the
-- response. You can use this pagination token to retrieve the next set of
-- faces.
listFaces_nextToken :: Lens.Lens' ListFaces (Prelude.Maybe Prelude.Text)
listFaces_nextToken = Lens.lens (\ListFaces' {nextToken} -> nextToken) (\s@ListFaces' {} a -> s {nextToken = a} :: ListFaces)

-- | ID of the collection from which to list the faces.
listFaces_collectionId :: Lens.Lens' ListFaces Prelude.Text
listFaces_collectionId = Lens.lens (\ListFaces' {collectionId} -> collectionId) (\s@ListFaces' {} a -> s {collectionId = a} :: ListFaces)

instance Core.AWSPager ListFaces where
  page rq rs
    | Core.stop
        ( rs
            Lens.^? listFacesResponse_nextToken
            Prelude.. Lens._Just
        ) =
        Prelude.Nothing
    | Core.stop
        ( rs
            Lens.^? listFacesResponse_faces
            Prelude.. Lens._Just
        ) =
        Prelude.Nothing
    | Prelude.otherwise =
        Prelude.Just
          Prelude.$ rq
          Prelude.& listFaces_nextToken
          Lens..~ rs
          Lens.^? listFacesResponse_nextToken
          Prelude.. Lens._Just

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

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

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

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

instance Data.ToJSON ListFaces where
  toJSON ListFaces' {..} =
    Data.object
      ( Prelude.catMaybes
          [ ("MaxResults" Data..=) Prelude.<$> maxResults,
            ("NextToken" Data..=) Prelude.<$> nextToken,
            Prelude.Just ("CollectionId" Data..= collectionId)
          ]
      )

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

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

-- | /See:/ 'newListFacesResponse' smart constructor.
data ListFacesResponse = ListFacesResponse'
  { -- | Version number of the face detection model associated with the input
    -- collection (@CollectionId@).
    faceModelVersion :: Prelude.Maybe Prelude.Text,
    -- | An array of @Face@ objects.
    faces :: Prelude.Maybe [Face],
    -- | If the response is truncated, Amazon Rekognition returns this token that
    -- you can use in the subsequent request to retrieve the next set of faces.
    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 'ListFacesResponse' 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:
--
-- 'faceModelVersion', 'listFacesResponse_faceModelVersion' - Version number of the face detection model associated with the input
-- collection (@CollectionId@).
--
-- 'faces', 'listFacesResponse_faces' - An array of @Face@ objects.
--
-- 'nextToken', 'listFacesResponse_nextToken' - If the response is truncated, Amazon Rekognition returns this token that
-- you can use in the subsequent request to retrieve the next set of faces.
--
-- 'httpStatus', 'listFacesResponse_httpStatus' - The response's http status code.
newListFacesResponse ::
  -- | 'httpStatus'
  Prelude.Int ->
  ListFacesResponse
newListFacesResponse pHttpStatus_ =
  ListFacesResponse'
    { faceModelVersion =
        Prelude.Nothing,
      faces = Prelude.Nothing,
      nextToken = Prelude.Nothing,
      httpStatus = pHttpStatus_
    }

-- | Version number of the face detection model associated with the input
-- collection (@CollectionId@).
listFacesResponse_faceModelVersion :: Lens.Lens' ListFacesResponse (Prelude.Maybe Prelude.Text)
listFacesResponse_faceModelVersion = Lens.lens (\ListFacesResponse' {faceModelVersion} -> faceModelVersion) (\s@ListFacesResponse' {} a -> s {faceModelVersion = a} :: ListFacesResponse)

-- | An array of @Face@ objects.
listFacesResponse_faces :: Lens.Lens' ListFacesResponse (Prelude.Maybe [Face])
listFacesResponse_faces = Lens.lens (\ListFacesResponse' {faces} -> faces) (\s@ListFacesResponse' {} a -> s {faces = a} :: ListFacesResponse) Prelude.. Lens.mapping Lens.coerced

-- | If the response is truncated, Amazon Rekognition returns this token that
-- you can use in the subsequent request to retrieve the next set of faces.
listFacesResponse_nextToken :: Lens.Lens' ListFacesResponse (Prelude.Maybe Prelude.Text)
listFacesResponse_nextToken = Lens.lens (\ListFacesResponse' {nextToken} -> nextToken) (\s@ListFacesResponse' {} a -> s {nextToken = a} :: ListFacesResponse)

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

instance Prelude.NFData ListFacesResponse where
  rnf ListFacesResponse' {..} =
    Prelude.rnf faceModelVersion
      `Prelude.seq` Prelude.rnf faces
      `Prelude.seq` Prelude.rnf nextToken
      `Prelude.seq` Prelude.rnf httpStatus