{-# 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.RDS.DescribeDBInstances
-- Copyright   : (c) 2013-2016 Brendan Hay
-- License     : Mozilla Public License, v. 2.0.
-- Maintainer  : Brendan Hay <brendan.g.hay@gmail.com>
-- Stability   : auto-generated
-- Portability : non-portable (GHC extensions)
--
-- Returns information about provisioned RDS instances. This API supports pagination.
--
--
--
-- This operation returns paginated results.
module Network.AWS.RDS.DescribeDBInstances
    (
    -- * Creating a Request
      describeDBInstances
    , DescribeDBInstances
    -- * Request Lenses
    , ddbiFilters
    , ddbiDBInstanceIdentifier
    , ddbiMarker
    , ddbiMaxRecords

    -- * Destructuring the Response
    , describeDBInstancesResponse
    , DescribeDBInstancesResponse
    -- * Response Lenses
    , ddbirsDBInstances
    , ddbirsMarker
    , ddbirsResponseStatus
    ) where

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

-- |
--
--
--
-- /See:/ 'describeDBInstances' smart constructor.
data DescribeDBInstances = DescribeDBInstances'
    { _ddbiFilters              :: !(Maybe [Filter])
    , _ddbiDBInstanceIdentifier :: !(Maybe Text)
    , _ddbiMarker               :: !(Maybe Text)
    , _ddbiMaxRecords           :: !(Maybe Int)
    } deriving (Eq,Read,Show,Data,Typeable,Generic)

-- | Creates a value of 'DescribeDBInstances' with the minimum fields required to make a request.
--
-- Use one of the following lenses to modify other fields as desired:
--
-- * 'ddbiFilters' - This parameter is not currently supported.
--
-- * 'ddbiDBInstanceIdentifier' - The user-supplied instance identifier. If this parameter is specified, information from only the specific DB instance is returned. This parameter isn't case-sensitive. Constraints:     * Must contain from 1 to 63 alphanumeric characters or hyphens     * First character must be a letter     * Cannot end with a hyphen or contain two consecutive hyphens
--
-- * 'ddbiMarker' - An optional pagination token provided by a previous @DescribeDBInstances@ request. If this parameter is specified, the response includes only records beyond the marker, up to the value specified by @MaxRecords@ .
--
-- * 'ddbiMaxRecords' - The maximum number of records to include in the response. If more records exist than the specified @MaxRecords@ value, a pagination token called a marker is included in the response so that the remaining results can be retrieved.  Default: 100 Constraints: Minimum 20, maximum 100.
describeDBInstances
    :: DescribeDBInstances
describeDBInstances =
    DescribeDBInstances'
    { _ddbiFilters = Nothing
    , _ddbiDBInstanceIdentifier = Nothing
    , _ddbiMarker = Nothing
    , _ddbiMaxRecords = Nothing
    }

-- | This parameter is not currently supported.
ddbiFilters :: Lens' DescribeDBInstances [Filter]
ddbiFilters = lens _ddbiFilters (\ s a -> s{_ddbiFilters = a}) . _Default . _Coerce;

-- | The user-supplied instance identifier. If this parameter is specified, information from only the specific DB instance is returned. This parameter isn't case-sensitive. Constraints:     * Must contain from 1 to 63 alphanumeric characters or hyphens     * First character must be a letter     * Cannot end with a hyphen or contain two consecutive hyphens
ddbiDBInstanceIdentifier :: Lens' DescribeDBInstances (Maybe Text)
ddbiDBInstanceIdentifier = lens _ddbiDBInstanceIdentifier (\ s a -> s{_ddbiDBInstanceIdentifier = a});

-- | An optional pagination token provided by a previous @DescribeDBInstances@ request. If this parameter is specified, the response includes only records beyond the marker, up to the value specified by @MaxRecords@ .
ddbiMarker :: Lens' DescribeDBInstances (Maybe Text)
ddbiMarker = lens _ddbiMarker (\ s a -> s{_ddbiMarker = a});

-- | The maximum number of records to include in the response. If more records exist than the specified @MaxRecords@ value, a pagination token called a marker is included in the response so that the remaining results can be retrieved.  Default: 100 Constraints: Minimum 20, maximum 100.
ddbiMaxRecords :: Lens' DescribeDBInstances (Maybe Int)
ddbiMaxRecords = lens _ddbiMaxRecords (\ s a -> s{_ddbiMaxRecords = a});

instance AWSPager DescribeDBInstances where
        page rq rs
          | stop (rs ^. ddbirsMarker) = Nothing
          | stop (rs ^. ddbirsDBInstances) = Nothing
          | otherwise =
            Just $ rq & ddbiMarker .~ rs ^. ddbirsMarker

instance AWSRequest DescribeDBInstances where
        type Rs DescribeDBInstances =
             DescribeDBInstancesResponse
        request = postQuery rds
        response
          = receiveXMLWrapper "DescribeDBInstancesResult"
              (\ s h x ->
                 DescribeDBInstancesResponse' <$>
                   (x .@? "DBInstances" .!@ mempty >>=
                      may (parseXMLList "DBInstance"))
                     <*> (x .@? "Marker")
                     <*> (pure (fromEnum s)))

instance Hashable DescribeDBInstances

instance NFData DescribeDBInstances

instance ToHeaders DescribeDBInstances where
        toHeaders = const mempty

instance ToPath DescribeDBInstances where
        toPath = const "/"

instance ToQuery DescribeDBInstances where
        toQuery DescribeDBInstances'{..}
          = mconcat
              ["Action" =: ("DescribeDBInstances" :: ByteString),
               "Version" =: ("2014-10-31" :: ByteString),
               "Filters" =:
                 toQuery (toQueryList "Filter" <$> _ddbiFilters),
               "DBInstanceIdentifier" =: _ddbiDBInstanceIdentifier,
               "Marker" =: _ddbiMarker,
               "MaxRecords" =: _ddbiMaxRecords]

-- | Contains the result of a successful invocation of the 'DescribeDBInstances' action.
--
--
--
-- /See:/ 'describeDBInstancesResponse' smart constructor.
data DescribeDBInstancesResponse = DescribeDBInstancesResponse'
    { _ddbirsDBInstances    :: !(Maybe [DBInstance])
    , _ddbirsMarker         :: !(Maybe Text)
    , _ddbirsResponseStatus :: !Int
    } deriving (Eq,Read,Show,Data,Typeable,Generic)

-- | Creates a value of 'DescribeDBInstancesResponse' with the minimum fields required to make a request.
--
-- Use one of the following lenses to modify other fields as desired:
--
-- * 'ddbirsDBInstances' - A list of 'DBInstance' instances.
--
-- * 'ddbirsMarker' - An optional pagination token provided by a previous request. If this parameter is specified, the response includes only records beyond the marker, up to the value specified by @MaxRecords@ .
--
-- * 'ddbirsResponseStatus' - -- | The response status code.
describeDBInstancesResponse
    :: Int -- ^ 'ddbirsResponseStatus'
    -> DescribeDBInstancesResponse
describeDBInstancesResponse pResponseStatus_ =
    DescribeDBInstancesResponse'
    { _ddbirsDBInstances = Nothing
    , _ddbirsMarker = Nothing
    , _ddbirsResponseStatus = pResponseStatus_
    }

-- | A list of 'DBInstance' instances.
ddbirsDBInstances :: Lens' DescribeDBInstancesResponse [DBInstance]
ddbirsDBInstances = lens _ddbirsDBInstances (\ s a -> s{_ddbirsDBInstances = a}) . _Default . _Coerce;

-- | An optional pagination token provided by a previous request. If this parameter is specified, the response includes only records beyond the marker, up to the value specified by @MaxRecords@ .
ddbirsMarker :: Lens' DescribeDBInstancesResponse (Maybe Text)
ddbirsMarker = lens _ddbirsMarker (\ s a -> s{_ddbirsMarker = a});

-- | -- | The response status code.
ddbirsResponseStatus :: Lens' DescribeDBInstancesResponse Int
ddbirsResponseStatus = lens _ddbirsResponseStatus (\ s a -> s{_ddbirsResponseStatus = a});

instance NFData DescribeDBInstancesResponse