{-# LANGUAGE DeriveDataTypeable #-}
{-# LANGUAGE DeriveGeneric      #-}
{-# LANGUAGE OverloadedStrings  #-}
{-# LANGUAGE RecordWildCards    #-}
{-# LANGUAGE TypeFamilies       #-}

{-# OPTIONS_GHC -fno-warn-unused-imports #-}
{-# OPTIONS_GHC -fno-warn-unused-binds   #-}
{-# OPTIONS_GHC -fno-warn-unused-matches #-}

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

-- |
-- Module      : Network.AWS.Rekognition.GetFaceDetection
-- Copyright   : (c) 2013-2018 Brendan Hay
-- License     : Mozilla Public License, v. 2.0.
-- Maintainer  : Brendan Hay <brendan.g.hay+amazonka@gmail.com>
-- Stability   : auto-generated
-- Portability : non-portable (GHC extensions)
--
-- Gets face detection results for a Rekognition Video analysis started by .
--
--
-- Face detection with Rekognition Video is an asynchronous operation. You start face detection by calling which returns a job identifier (@JobId@ ). When the face detection operation finishes, Rekognition Video publishes a completion status to the Amazon Simple Notification Service topic registered in the initial call to @StartFaceDetection@ . To get the results of the face detection operation, first check that the status value published to the Amazon SNS topic is @SUCCEEDED@ . If so, call and pass the job identifier (@JobId@ ) from the initial call to @StartFaceDetection@ .
--
-- @GetFaceDetection@ returns an array of detected faces (@Faces@ ) sorted by the time the faces were detected.
--
-- Use MaxResults parameter to limit the number of labels returned. If there are more results than specified in @MaxResults@ , the value of @NextToken@ in the operation response contains a pagination token for getting the next set of results. To get the next page of results, call @GetFaceDetection@ and populate the @NextToken@ request parameter with the token value returned from the previous call to @GetFaceDetection@ .
--
module Network.AWS.Rekognition.GetFaceDetection
    (
    -- * Creating a Request
      getFaceDetection
    , GetFaceDetection
    -- * Request Lenses
    , gfdNextToken
    , gfdMaxResults
    , gfdJobId

    -- * Destructuring the Response
    , getFaceDetectionResponse
    , GetFaceDetectionResponse
    -- * Response Lenses
    , gfdrsNextToken
    , gfdrsVideoMetadata
    , gfdrsStatusMessage
    , gfdrsFaces
    , gfdrsJobStatus
    , gfdrsResponseStatus
    ) where

import Network.AWS.Lens
import Network.AWS.Prelude
import Network.AWS.Rekognition.Types
import Network.AWS.Rekognition.Types.Product
import Network.AWS.Request
import Network.AWS.Response

-- | /See:/ 'getFaceDetection' smart constructor.
data GetFaceDetection = GetFaceDetection'
  { _gfdNextToken  :: !(Maybe Text)
  , _gfdMaxResults :: !(Maybe Nat)
  , _gfdJobId      :: !Text
  } deriving (Eq, Read, Show, Data, Typeable, Generic)


-- | Creates a value of 'GetFaceDetection' with the minimum fields required to make a request.
--
-- Use one of the following lenses to modify other fields as desired:
--
-- * 'gfdNextToken' - If the previous response was incomplete (because there are more faces to retrieve), Rekognition Video returns a pagination token in the response. You can use this pagination token to retrieve the next set of faces.
--
-- * 'gfdMaxResults' - Maximum number of results to return per paginated call. The largest value you can specify is 1000. If you specify a value greater than 1000, a maximum of 1000 results is returned. The default value is 1000.
--
-- * 'gfdJobId' - Unique identifier for the face detection job. The @JobId@ is returned from @StartFaceDetection@ .
getFaceDetection
    :: Text -- ^ 'gfdJobId'
    -> GetFaceDetection
getFaceDetection pJobId_ =
  GetFaceDetection'
    {_gfdNextToken = Nothing, _gfdMaxResults = Nothing, _gfdJobId = pJobId_}


-- | If the previous response was incomplete (because there are more faces to retrieve), Rekognition Video returns a pagination token in the response. You can use this pagination token to retrieve the next set of faces.
gfdNextToken :: Lens' GetFaceDetection (Maybe Text)
gfdNextToken = lens _gfdNextToken (\ s a -> s{_gfdNextToken = a})

-- | Maximum number of results to return per paginated call. The largest value you can specify is 1000. If you specify a value greater than 1000, a maximum of 1000 results is returned. The default value is 1000.
gfdMaxResults :: Lens' GetFaceDetection (Maybe Natural)
gfdMaxResults = lens _gfdMaxResults (\ s a -> s{_gfdMaxResults = a}) . mapping _Nat

-- | Unique identifier for the face detection job. The @JobId@ is returned from @StartFaceDetection@ .
gfdJobId :: Lens' GetFaceDetection Text
gfdJobId = lens _gfdJobId (\ s a -> s{_gfdJobId = a})

instance AWSRequest GetFaceDetection where
        type Rs GetFaceDetection = GetFaceDetectionResponse
        request = postJSON rekognition
        response
          = receiveJSON
              (\ s h x ->
                 GetFaceDetectionResponse' <$>
                   (x .?> "NextToken") <*> (x .?> "VideoMetadata") <*>
                     (x .?> "StatusMessage")
                     <*> (x .?> "Faces" .!@ mempty)
                     <*> (x .?> "JobStatus")
                     <*> (pure (fromEnum s)))

instance Hashable GetFaceDetection where

instance NFData GetFaceDetection where

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

instance ToJSON GetFaceDetection where
        toJSON GetFaceDetection'{..}
          = object
              (catMaybes
                 [("NextToken" .=) <$> _gfdNextToken,
                  ("MaxResults" .=) <$> _gfdMaxResults,
                  Just ("JobId" .= _gfdJobId)])

instance ToPath GetFaceDetection where
        toPath = const "/"

instance ToQuery GetFaceDetection where
        toQuery = const mempty

-- | /See:/ 'getFaceDetectionResponse' smart constructor.
data GetFaceDetectionResponse = GetFaceDetectionResponse'
  { _gfdrsNextToken      :: !(Maybe Text)
  , _gfdrsVideoMetadata  :: !(Maybe VideoMetadata)
  , _gfdrsStatusMessage  :: !(Maybe Text)
  , _gfdrsFaces          :: !(Maybe [FaceDetection])
  , _gfdrsJobStatus      :: !(Maybe VideoJobStatus)
  , _gfdrsResponseStatus :: !Int
  } deriving (Eq, Read, Show, Data, Typeable, Generic)


-- | Creates a value of 'GetFaceDetectionResponse' with the minimum fields required to make a request.
--
-- Use one of the following lenses to modify other fields as desired:
--
-- * 'gfdrsNextToken' - 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.
--
-- * 'gfdrsVideoMetadata' - Information about a video that Rekognition Video analyzed. @Videometadata@ is returned in every page of paginated responses from a Amazon Rekognition video operation.
--
-- * 'gfdrsStatusMessage' - If the job fails, @StatusMessage@ provides a descriptive error message.
--
-- * 'gfdrsFaces' - An array of faces detected in the video. Each element contains a detected face's details and the time, in milliseconds from the start of the video, the face was detected.
--
-- * 'gfdrsJobStatus' - The current status of the face detection job.
--
-- * 'gfdrsResponseStatus' - -- | The response status code.
getFaceDetectionResponse
    :: Int -- ^ 'gfdrsResponseStatus'
    -> GetFaceDetectionResponse
getFaceDetectionResponse pResponseStatus_ =
  GetFaceDetectionResponse'
    { _gfdrsNextToken = Nothing
    , _gfdrsVideoMetadata = Nothing
    , _gfdrsStatusMessage = Nothing
    , _gfdrsFaces = Nothing
    , _gfdrsJobStatus = Nothing
    , _gfdrsResponseStatus = pResponseStatus_
    }


-- | 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.
gfdrsNextToken :: Lens' GetFaceDetectionResponse (Maybe Text)
gfdrsNextToken = lens _gfdrsNextToken (\ s a -> s{_gfdrsNextToken = a})

-- | Information about a video that Rekognition Video analyzed. @Videometadata@ is returned in every page of paginated responses from a Amazon Rekognition video operation.
gfdrsVideoMetadata :: Lens' GetFaceDetectionResponse (Maybe VideoMetadata)
gfdrsVideoMetadata = lens _gfdrsVideoMetadata (\ s a -> s{_gfdrsVideoMetadata = a})

-- | If the job fails, @StatusMessage@ provides a descriptive error message.
gfdrsStatusMessage :: Lens' GetFaceDetectionResponse (Maybe Text)
gfdrsStatusMessage = lens _gfdrsStatusMessage (\ s a -> s{_gfdrsStatusMessage = a})

-- | An array of faces detected in the video. Each element contains a detected face's details and the time, in milliseconds from the start of the video, the face was detected.
gfdrsFaces :: Lens' GetFaceDetectionResponse [FaceDetection]
gfdrsFaces = lens _gfdrsFaces (\ s a -> s{_gfdrsFaces = a}) . _Default . _Coerce

-- | The current status of the face detection job.
gfdrsJobStatus :: Lens' GetFaceDetectionResponse (Maybe VideoJobStatus)
gfdrsJobStatus = lens _gfdrsJobStatus (\ s a -> s{_gfdrsJobStatus = a})

-- | -- | The response status code.
gfdrsResponseStatus :: Lens' GetFaceDetectionResponse Int
gfdrsResponseStatus = lens _gfdrsResponseStatus (\ s a -> s{_gfdrsResponseStatus = a})

instance NFData GetFaceDetectionResponse where