{-# 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.StepFunctions.ListExecutions
-- 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)
--
-- Lists the executions of a state machine that meet the filtering criteria.
--
--
-- If a @nextToken@ is returned by a previous call, there are more results available. To retrieve the next page of results, make the call again using the returned token in @nextToken@ . Keep all other arguments unchanged.
--
--
-- This operation returns paginated results.
module Network.AWS.StepFunctions.ListExecutions
    (
    -- * Creating a Request
      listExecutions
    , ListExecutions
    -- * Request Lenses
    , leStatusFilter
    , leNextToken
    , leMaxResults
    , leStateMachineARN

    -- * Destructuring the Response
    , listExecutionsResponse
    , ListExecutionsResponse
    -- * Response Lenses
    , lersNextToken
    , lersResponseStatus
    , lersExecutions
    ) where

import Network.AWS.Lens
import Network.AWS.Pager
import Network.AWS.Prelude
import Network.AWS.Request
import Network.AWS.Response
import Network.AWS.StepFunctions.Types
import Network.AWS.StepFunctions.Types.Product

-- | /See:/ 'listExecutions' smart constructor.
data ListExecutions = ListExecutions'
  { _leStatusFilter    :: !(Maybe ExecutionStatus)
  , _leNextToken       :: !(Maybe Text)
  , _leMaxResults      :: !(Maybe Nat)
  , _leStateMachineARN :: !Text
  } deriving (Eq, Read, Show, Data, Typeable, Generic)


-- | Creates a value of 'ListExecutions' with the minimum fields required to make a request.
--
-- Use one of the following lenses to modify other fields as desired:
--
-- * 'leStatusFilter' - If specified, only list the executions whose current execution status matches the given filter.
--
-- * 'leNextToken' - If a @nextToken@ is returned by a previous call, there are more results available. To retrieve the next page of results, make the call again using the returned token in @nextToken@ . Keep all other arguments unchanged. The configured @maxResults@ determines how many results can be returned in a single call.
--
-- * 'leMaxResults' - The maximum number of results that are returned per call. You can use @nextToken@ to obtain further pages of results. The default is 100 and the maximum allowed page size is 100. A value of 0 uses the default. This is only an upper limit. The actual number of results returned per call might be fewer than the specified maximum.
--
-- * 'leStateMachineARN' - The Amazon Resource Name (ARN) of the state machine whose executions is listed.
listExecutions
    :: Text -- ^ 'leStateMachineARN'
    -> ListExecutions
listExecutions pStateMachineARN_ =
  ListExecutions'
    { _leStatusFilter = Nothing
    , _leNextToken = Nothing
    , _leMaxResults = Nothing
    , _leStateMachineARN = pStateMachineARN_
    }


-- | If specified, only list the executions whose current execution status matches the given filter.
leStatusFilter :: Lens' ListExecutions (Maybe ExecutionStatus)
leStatusFilter = lens _leStatusFilter (\ s a -> s{_leStatusFilter = a})

-- | If a @nextToken@ is returned by a previous call, there are more results available. To retrieve the next page of results, make the call again using the returned token in @nextToken@ . Keep all other arguments unchanged. The configured @maxResults@ determines how many results can be returned in a single call.
leNextToken :: Lens' ListExecutions (Maybe Text)
leNextToken = lens _leNextToken (\ s a -> s{_leNextToken = a})

-- | The maximum number of results that are returned per call. You can use @nextToken@ to obtain further pages of results. The default is 100 and the maximum allowed page size is 100. A value of 0 uses the default. This is only an upper limit. The actual number of results returned per call might be fewer than the specified maximum.
leMaxResults :: Lens' ListExecutions (Maybe Natural)
leMaxResults = lens _leMaxResults (\ s a -> s{_leMaxResults = a}) . mapping _Nat

-- | The Amazon Resource Name (ARN) of the state machine whose executions is listed.
leStateMachineARN :: Lens' ListExecutions Text
leStateMachineARN = lens _leStateMachineARN (\ s a -> s{_leStateMachineARN = a})

instance AWSPager ListExecutions where
        page rq rs
          | stop (rs ^. lersNextToken) = Nothing
          | stop (rs ^. lersExecutions) = Nothing
          | otherwise =
            Just $ rq & leNextToken .~ rs ^. lersNextToken

instance AWSRequest ListExecutions where
        type Rs ListExecutions = ListExecutionsResponse
        request = postJSON stepFunctions
        response
          = receiveJSON
              (\ s h x ->
                 ListExecutionsResponse' <$>
                   (x .?> "nextToken") <*> (pure (fromEnum s)) <*>
                     (x .?> "executions" .!@ mempty))

instance Hashable ListExecutions where

instance NFData ListExecutions where

instance ToHeaders ListExecutions where
        toHeaders
          = const
              (mconcat
                 ["X-Amz-Target" =#
                    ("AWSStepFunctions.ListExecutions" :: ByteString),
                  "Content-Type" =#
                    ("application/x-amz-json-1.0" :: ByteString)])

instance ToJSON ListExecutions where
        toJSON ListExecutions'{..}
          = object
              (catMaybes
                 [("statusFilter" .=) <$> _leStatusFilter,
                  ("nextToken" .=) <$> _leNextToken,
                  ("maxResults" .=) <$> _leMaxResults,
                  Just ("stateMachineArn" .= _leStateMachineARN)])

instance ToPath ListExecutions where
        toPath = const "/"

instance ToQuery ListExecutions where
        toQuery = const mempty

-- | /See:/ 'listExecutionsResponse' smart constructor.
data ListExecutionsResponse = ListExecutionsResponse'
  { _lersNextToken      :: !(Maybe Text)
  , _lersResponseStatus :: !Int
  , _lersExecutions     :: ![ExecutionListItem]
  } deriving (Eq, Read, Show, Data, Typeable, Generic)


-- | Creates a value of 'ListExecutionsResponse' with the minimum fields required to make a request.
--
-- Use one of the following lenses to modify other fields as desired:
--
-- * 'lersNextToken' - If a @nextToken@ is returned by a previous call, there are more results available. To retrieve the next page of results, make the call again using the returned token in @nextToken@ . Keep all other arguments unchanged. The configured @maxResults@ determines how many results can be returned in a single call.
--
-- * 'lersResponseStatus' - -- | The response status code.
--
-- * 'lersExecutions' - The list of matching executions.
listExecutionsResponse
    :: Int -- ^ 'lersResponseStatus'
    -> ListExecutionsResponse
listExecutionsResponse pResponseStatus_ =
  ListExecutionsResponse'
    { _lersNextToken = Nothing
    , _lersResponseStatus = pResponseStatus_
    , _lersExecutions = mempty
    }


-- | If a @nextToken@ is returned by a previous call, there are more results available. To retrieve the next page of results, make the call again using the returned token in @nextToken@ . Keep all other arguments unchanged. The configured @maxResults@ determines how many results can be returned in a single call.
lersNextToken :: Lens' ListExecutionsResponse (Maybe Text)
lersNextToken = lens _lersNextToken (\ s a -> s{_lersNextToken = a})

-- | -- | The response status code.
lersResponseStatus :: Lens' ListExecutionsResponse Int
lersResponseStatus = lens _lersResponseStatus (\ s a -> s{_lersResponseStatus = a})

-- | The list of matching executions.
lersExecutions :: Lens' ListExecutionsResponse [ExecutionListItem]
lersExecutions = lens _lersExecutions (\ s a -> s{_lersExecutions = a}) . _Coerce

instance NFData ListExecutionsResponse where