{-# LANGUAGE DeriveGeneric              #-}
{-# LANGUAGE FlexibleContexts           #-}
{-# LANGUAGE FlexibleInstances          #-}
{-# LANGUAGE GeneralizedNewtypeDeriving #-}
{-# LANGUAGE MultiParamTypeClasses      #-}
{-# LANGUAGE OverloadedStrings          #-}
{-# LANGUAGE RecordWildCards            #-}
{-# LANGUAGE UndecidableInstances       #-}

-------------------------------------------------------------------------------
-- |
-- Module : Database.Bloodhound.Types
-- Copyright : (C) 2014 Chris Allen
-- License : BSD-style (see the file LICENSE)
-- Maintainer : Chris Allen <cma@bitemyapp.com
-- Stability : provisional
-- Portability : DeriveGeneric, RecordWildCards
--
-- Data types for describing actions and data structures performed to interact
-- with Elasticsearch. The two main buckets your queries against Elasticsearch
-- will fall into are 'Query's and 'Filter's. 'Filter's are more like
-- traditional database constraints and often have preferable performance
-- properties. 'Query's support human-written textual queries, such as fuzzy
-- queries.
-------------------------------------------------------------------------------



module Database.Bloodhound.Types
       ( defaultCache
       , defaultIndexSettings
       , defaultIndexDocumentSettings
       , mkSort
       , showText
       , unpackId
       , mkMatchQuery
       , mkMultiMatchQuery
       , mkBoolQuery
       , mkRangeQuery
       , mkQueryStringQuery
       , mkAggregations
       , mkTermsAggregation
       , mkTermsScriptAggregation
       , mkDateHistogram
       , mkDocVersion
       , docVersionNumber
       , toTerms
       , toDateHistogram
       , omitNulls
       , BH
       , runBH
       , BHEnv(..)
       , MonadBH(..)
       , Version(..)
       , Status(..)
       , Existence(..)
       , NullValue(..)
       , IndexSettings(..)
       , Server(..)
       , Reply
       , EsResult(..)
       , DocVersion
       , ExternalDocVersion(..)
       , VersionControl(..)
       , IndexDocumentSettings(..)
       , Query(..)
       , Search(..)
       , SearchResult(..)
       , SearchHits(..)
       , TrackSortScores
       , From(..)
       , Size(..)
       , ShardResult(..)
       , Hit(..)
       , Filter(..)
       , Seminearring(..)
       , BoolMatch(..)
       , Term(..)
       , GeoPoint(..)
       , GeoBoundingBoxConstraint(..)
       , GeoBoundingBox(..)
       , GeoFilterType(..)
       , Distance(..)
       , DistanceUnit(..)
       , DistanceType(..)
       , DistanceRange(..)
       , OptimizeBbox(..)
       , LatLon(..)
       , RangeValue(..)
       , RangeExecution(..)
       , LessThan(..)
       , LessThanEq(..)
       , GreaterThan(..)
       , GreaterThanEq(..)
       , LessThanD(..)
       , LessThanEqD(..)
       , GreaterThanD(..)
       , GreaterThanEqD(..)
       , Regexp(..)
       , RegexpFlags(..)
       , RegexpFlag(..)
       , FieldName(..)
       , IndexName(..)
       , MappingName(..)
       , DocId(..)
       , CacheName(..)
       , CacheKey(..)
       , BulkOperation(..)
       , ReplicaCount(..)
       , ShardCount(..)
       , Sort
       , SortMode(..)
       , SortOrder(..)
       , SortSpec(..)
       , DefaultSort(..)
       , Missing(..)
       , OpenCloseIndex(..)
       , Method
       , Boost(..)
       , MatchQuery(..)
       , MultiMatchQuery(..)
       , BoolQuery(..)
       , BoostingQuery(..)
       , CommonTermsQuery(..)
       , DisMaxQuery(..)
       , FilteredQuery(..)
       , FuzzyLikeThisQuery(..)
       , FuzzyLikeFieldQuery(..)
       , FuzzyQuery(..)
       , HasChildQuery(..)
       , HasParentQuery(..)
       , IndicesQuery(..)
       , MoreLikeThisQuery(..)
       , MoreLikeThisFieldQuery(..)
       , NestedQuery(..)
       , PrefixQuery(..)
       , QueryStringQuery(..)
       , SimpleQueryStringQuery(..)
       , RangeQuery(..)
       , RegexpQuery(..)
       , QueryString(..)
       , BooleanOperator(..)
       , ZeroTermsQuery(..)
       , CutoffFrequency(..)
       , Analyzer(..)
       , MaxExpansions(..)
       , Lenient(..)
       , MatchQueryType(..)
       , MultiMatchQueryType(..)
       , Tiebreaker(..)
       , MinimumMatch(..)
       , DisableCoord(..)
       , CommonMinimumMatch(..)
       , MinimumMatchHighLow(..)
       , PrefixLength(..)
       , Fuzziness(..)
       , IgnoreTermFrequency(..)
       , MaxQueryTerms(..)
       , ScoreType(..)
       , Score
       , Cache
       , TypeName(..)
       , BoostTerms(..)
       , MaxWordLength(..)
       , MinWordLength(..)
       , MaxDocFrequency(..)
       , MinDocFrequency(..)
       , PhraseSlop(..)
       , StopWord(..)
       , QueryPath(..)
       , MinimumTermFrequency(..)
       , PercentMatch(..)
       , FieldDefinition(..)
       , MappingField(..)
       , Mapping(..)
       , AllowLeadingWildcard(..)
       , LowercaseExpanded(..)
       , GeneratePhraseQueries(..)
       , Locale(..)
       , AnalyzeWildcard(..)
       , EnablePositionIncrements(..)
       , SimpleQueryFlag(..)
       , FieldOrFields(..)
       , Monoid(..)
       , ToJSON(..)
       , Interval(..)
       , TimeInterval(..)
       , ExecutionHint(..)
       , CollectionMode(..)
       , TermOrder(..)
       , TermInclusion(..)

       , Aggregation(..)
       , Aggregations
       , AggregationResults
       , Bucket(..)
       , BucketAggregation(..)
       , TermsAggregation(..)
       , DateHistogramAggregation(..)

       , Highlights(..)
       , FieldHighlight(..)
       , HighlightSettings(..)
       , PlainHighlight(..)
       , PostingsHighlight(..)
       , FastVectorHighlight(..)
       , CommonHighlight(..)
       , NonPostings(..)
       , HighlightEncoder(..)
       , HighlightTag(..)
       , HitHighlight

       , TermsResult(..)
       , DateHistogramResult(..)
         ) where

import           Control.Applicative
import           Control.Monad.Error
import           Control.Monad.Reader
import           Control.Monad.State
import           Control.Monad.Writer
import           Data.Aeson
import           Data.Aeson.Types                (Pair, emptyObject, parseMaybe)
import qualified Data.ByteString.Lazy.Char8      as L
import           Data.List                       (nub)
import           Data.List.NonEmpty              (NonEmpty (..), toList)
import qualified Data.Map.Strict                 as M
import           Data.Maybe
import           Data.Text                       (Text)
import qualified Data.Text                       as T
import           Data.Time.Clock                 (UTCTime)
import qualified Data.Vector                     as V
import           GHC.Enum
import           GHC.Generics                    (Generic)
import           Network.HTTP.Client
import qualified Network.HTTP.Types.Method       as NHTM

import           Database.Bloodhound.Types.Class

-- $setup
-- >>> :set -XOverloadedStrings
-- >>> import Database.Bloodhound
-- >>> let testServer = (Server "http://localhost:9200")
-- >>> let testIndex = IndexName "twitter"
-- >>> let testMapping = MappingName "tweet"
-- >>> let defaultIndexSettings = IndexSettings (ShardCount 3) (ReplicaCount 2)

-- defaultIndexSettings is exported by Database.Bloodhound as well
-- no trailing slashes in servers, library handles building the path.

{-| Common environment for Elasticsearch calls. Connections will be
    pipelined according to the provided HTTP connection manager.
-}
data BHEnv = BHEnv { bhServer  :: Server
                   , bhManager :: Manager
                   }

{-| All API calls to Elasticsearch operate within
    MonadBH. The idea is that it can be easily embedded in your
    own monad transformer stack. A default instance for a ReaderT and
    alias 'BH' is provided for the simple case.
-}
class (Functor m, Applicative m, MonadIO m) => MonadBH m where
  getBHEnv :: m BHEnv

newtype BH m a = BH {
      unBH :: ReaderT BHEnv m a
    } deriving ( Functor
               , Applicative
               , Monad
               , MonadIO
               , MonadState s
               , MonadWriter w
               , MonadError e
               , Alternative
               , MonadPlus
               , MonadFix)

instance MonadTrans BH where
  lift = BH . lift

instance (MonadReader r m) => MonadReader r (BH m) where
    ask = lift ask
    local f (BH (ReaderT m)) = BH $ ReaderT $ \r ->
      local f (m r)

instance (Functor m, Applicative m, MonadIO m) => MonadBH (BH m) where
  getBHEnv = BH getBHEnv


instance (Functor m, Applicative m, MonadIO m) => MonadBH (ReaderT BHEnv m) where
  getBHEnv = ask

runBH :: BHEnv -> BH m a -> m a
runBH e f = runReaderT (unBH f) e

{-| 'Version' is embedded in 'Status' -}
data Version = Version { number          :: Text
                       , build_hash      :: Text
                       , build_timestamp :: UTCTime
                       , build_snapshot  :: Bool
                       , lucene_version  :: Text } deriving (Eq, Show, Generic)

{-| 'Status' is a data type for describing the JSON body returned by
    Elasticsearch when you query its status. This was deprecated in 1.2.0.

   <http://www.elasticsearch.org/guide/en/elasticsearch/reference/current/indices-status.html#indices-status>
-}

data Status = Status { ok      :: Maybe Bool
                     , status  :: Int
                     , name    :: Text
                     , version :: Version
                     , tagline :: Text } deriving (Eq, Show)

{-| 'IndexSettings' is used to configure the shards and replicas when you create
   an Elasticsearch Index.

   <http://www.elasticsearch.org/guide/en/elasticsearch/reference/current/indices-create-index.html>
-}

data IndexSettings =
  IndexSettings { indexShards   :: ShardCount
                , indexReplicas :: ReplicaCount } deriving (Eq, Show)

{-| 'defaultIndexSettings' is an 'IndexSettings' with 3 shards and 2 replicas. -}
defaultIndexSettings :: IndexSettings
defaultIndexSettings =  IndexSettings (ShardCount 3) (ReplicaCount 2)

{-| 'Reply' and 'Method' are type synonyms from 'Network.HTTP.Types.Method.Method' -}
type Reply = Network.HTTP.Client.Response L.ByteString
type Method = NHTM.Method

{-| 'OpenCloseIndex' is a sum type for opening and closing indices.

   <http://www.elasticsearch.org/guide/en/elasticsearch/reference/current/indices-open-close.html>
-}
data OpenCloseIndex = OpenIndex | CloseIndex deriving (Eq, Show)

data FieldType = GeoPointType
               | GeoShapeType
               | FloatType
               | IntegerType
               | LongType
               | ShortType
               | ByteType deriving (Eq, Show)

data FieldDefinition =
  FieldDefinition { fieldType :: FieldType } deriving (Eq, Show)

data MappingField =
  MappingField   { mappingFieldName :: FieldName
                 , fieldDefinition  :: FieldDefinition } deriving (Eq, Show)

{-| Support for type reification of 'Mapping's is currently incomplete, for
    now the mapping API verbiage expects a 'ToJSON'able blob.

    Indexes have mappings, mappings are schemas for the documents contained in the
    index. I'd recommend having only one mapping per index, always having a mapping,
    and keeping different kinds of documents separated if possible.
-}
data Mapping = Mapping { typeName      :: TypeName
                       , mappingFields :: [MappingField] } deriving (Eq, Show)

{-| 'BulkOperation' is a sum type for expressing the four kinds of bulk
    operation index, create, delete, and update. 'BulkIndex' behaves like an
    "upsert", 'BulkCreate' will fail if a document already exists at the DocId.

   <http://www.elasticsearch.org/guide/en/elasticsearch/reference/current/docs-bulk.html#docs-bulk>
-}
data BulkOperation =
    BulkIndex  IndexName MappingName DocId Value
  | BulkCreate IndexName MappingName DocId Value
  | BulkDelete IndexName MappingName DocId
  | BulkUpdate IndexName MappingName DocId Value deriving (Eq, Show)

{-| 'EsResult' describes the standard wrapper JSON document that you see in
    successful Elasticsearch responses.
-}
data EsResult a = EsResult { _index   :: Text
                           , _type    :: Text
                           , _id      :: Text
                           , _version :: DocVersion
                           , found    :: Maybe Bool
                           , _source  :: a } deriving (Eq, Show)

{-| 'DocVersion' is an integer version number for a document between 1
and 9.2e+18 used for <<https://www.elastic.co/guide/en/elasticsearch/guide/current/optimistic-concurrency-control.html optimistic concurrency control>>.
-}
newtype DocVersion = DocVersion {
      docVersionNumber :: Int
    } deriving (Eq, Show, Ord, ToJSON)

-- | Smart constructor for in-range doc version
mkDocVersion :: Int -> Maybe DocVersion
mkDocVersion i
  | i >= (docVersionNumber minBound) && i <= (docVersionNumber maxBound) =
    Just $ DocVersion i
  | otherwise = Nothing


{-| 'ExternalDocVersion' is a convenience wrapper if your code uses its
own version numbers instead of ones from ES.
-}
newtype ExternalDocVersion = ExternalDocVersion DocVersion
    deriving (Eq, Show, Ord, Bounded, Enum, ToJSON)

{-| 'VersionControl' is specified when indexing documents as a
optimistic concurrency control.
-}
data VersionControl = NoVersionControl
                    -- ^ Don't send a version. This is a pure overwrite.
                    | InternalVersion DocVersion
                    -- ^ Use the default ES versioning scheme. Only
                    -- index the document if the version is the same
                    -- as the one specified. Only applicable to
                    -- updates, as you should be getting Version from
                    -- a search result.
                    | ExternalGT ExternalDocVersion
                    -- ^ Use your own version numbering. Only index
                    -- the document if the version is strictly higher
                    -- OR the document doesn't exist. The given
                    -- version will be used as the new version number
                    -- for the stored document. N.B. All updates must
                    -- increment this number, meaning there is some
                    -- global, external ordering of updates.
                    | ExternalGTE ExternalDocVersion
                    -- ^ Use your own version numbering. Only index
                    -- the document if the version is equal or higher
                    -- than the stored version. Will succeed if there
                    -- is no existing document. The given version will
                    -- be used as the new version number for the
                    -- stored document. Use with care, as this could
                    -- result in data loss.
                    | ForceVersion ExternalDocVersion
                    -- ^ The document will always be indexed and the
                    -- given version will be the new version. This is
                    -- typically used for correcting errors. Use with
                    -- care, as this could result in data loss.
                    deriving (Show, Eq, Ord)

{-| 'IndexDocumentSettings' are special settings supplied when indexing
a document. For the best backwards compatiblity when new fields are
added, you should probably prefer to start with 'defaultIndexDocumentSettings'
-}
data IndexDocumentSettings = IndexDocumentSettings {
      idsVersionControl :: VersionControl
    }

{-| Reasonable default settings. Chooses no version control.
-}
defaultIndexDocumentSettings :: IndexDocumentSettings
defaultIndexDocumentSettings = IndexDocumentSettings NoVersionControl

{-| 'Sort' is a synonym for a list of 'SortSpec's. Sort behavior is order
    dependent with later sorts acting as tie-breakers for earlier sorts.
-}
type Sort = [SortSpec]

{-| The two main kinds of 'SortSpec' are 'DefaultSortSpec' and
    'GeoDistanceSortSpec'. The latter takes a 'SortOrder', 'GeoPoint', and
    'DistanceUnit' to express "nearness" to a single geographical point as a
    sort specification.

<http://www.elasticsearch.org/guide/en/elasticsearch/reference/current/search-request-sort.html#search-request-sort>
-}
data SortSpec = DefaultSortSpec DefaultSort
              | GeoDistanceSortSpec SortOrder GeoPoint DistanceUnit deriving (Eq, Show)

{-| 'DefaultSort' is usually the kind of 'SortSpec' you'll want. There's a
    'mkSort' convenience function for when you want to specify only the most
    common parameters.

<http://www.elasticsearch.org/guide/en/elasticsearch/reference/current/search-request-sort.html#search-request-sort>
-}
data DefaultSort =
  DefaultSort { sortFieldName  :: FieldName
              , sortOrder      :: SortOrder
                                  -- default False
              , ignoreUnmapped :: Bool
              , sortMode       :: Maybe SortMode
              , missingSort    :: Maybe Missing
              , nestedFilter   :: Maybe Filter } deriving (Eq, Show)

{-| 'SortOrder' is 'Ascending' or 'Descending', as you might expect. These get
    encoded into "asc" or "desc" when turned into JSON.

<http://www.elasticsearch.org/guide/en/elasticsearch/reference/current/search-request-sort.html#search-request-sort>
-}
data SortOrder = Ascending
               | Descending deriving (Eq, Show)

{-| 'Missing' prescribes how to handle missing fields. A missing field can be
    sorted last, first, or using a custom value as a substitute.

<http://www.elasticsearch.org/guide/en/elasticsearch/reference/current/search-request-sort.html#_missing_values>
-}
data Missing = LastMissing
             | FirstMissing
             | CustomMissing Text deriving (Eq, Show)

{-| 'SortMode' prescribes how to handle sorting array/multi-valued fields.

http://www.elasticsearch.org/guide/en/elasticsearch/reference/current/search-request-sort.html#_sort_mode_option
-}
data SortMode = SortMin
              | SortMax
              | SortSum
              | SortAvg deriving (Eq, Show)

{-| 'mkSort' defaults everything but the 'FieldName' and the 'SortOrder' so
    that you can concisely describe the usual kind of 'SortSpec's you want.
-}
mkSort :: FieldName -> SortOrder -> DefaultSort
mkSort fieldName sOrder = DefaultSort fieldName sOrder False Nothing Nothing Nothing

{-| 'Cache' is for telling ES whether it should cache a 'Filter' not.
    'Query's cannot be cached.
-}
type Cache   = Bool -- caching on/off
defaultCache :: Cache
defaultCache = False

{-| 'PrefixValue' is used in 'PrefixQuery' as the main query component.
-}
type PrefixValue = Text

{-| 'BooleanOperator' is the usual And/Or operators with an ES compatible
    JSON encoding baked in. Used all over the place.
-}
data BooleanOperator = And | Or deriving (Eq, Show)

{-| 'ShardCount' is part of 'IndexSettings'
-}
newtype ShardCount = ShardCount Int deriving (Eq, Show, Generic)

{-| 'ReplicaCount' is part of 'IndexSettings'
-}
newtype ReplicaCount = ReplicaCount Int deriving (Eq, Show, Generic)

{-| 'Server' is used with the client functions to point at the ES instance
-}
newtype Server = Server Text deriving (Eq, Show)

{-| 'IndexName' is used to describe which index to query/create/delete
-}
newtype IndexName = IndexName Text deriving (Eq, Generic, Show)

{-| 'MappingName' is part of mappings which are how ES describes and schematizes
    the data in the indices.
-}
newtype MappingName = MappingName Text deriving (Eq, Generic, Show)

{-| 'DocId' is a generic wrapper value for expressing unique Document IDs.
    Can be set by the user or created by ES itself. Often used in client
    functions for poking at specific documents.
-}
newtype DocId = DocId Text deriving (Eq, Generic, Show)

{-| 'QueryString' is used to wrap query text bodies, be they human written or not.
-}
newtype QueryString = QueryString Text deriving (Eq, Generic, Show)

{-| 'FieldName' is used all over the place wherever a specific field within
     a document needs to be specified, usually in 'Query's or 'Filter's.
-}
newtype FieldName = FieldName Text deriving (Eq, Show)

{-| 'CacheName' is used in 'RegexpFilter' for describing the
    'CacheKey' keyed caching behavior.
-}
newtype CacheName = CacheName Text deriving (Eq, Show)

{-| 'CacheKey' is used in 'RegexpFilter' to key regex caching.
-}
newtype CacheKey =
  CacheKey Text deriving (Eq, Show)
newtype Existence =
  Existence Bool deriving (Eq, Show)
newtype NullValue =
  NullValue Bool deriving (Eq, Show)
newtype CutoffFrequency =
  CutoffFrequency Double deriving (Eq, Show, Generic)
newtype Analyzer =
  Analyzer Text deriving (Eq, Show, Generic)
newtype MaxExpansions =
  MaxExpansions Int deriving (Eq, Show, Generic)

{-| 'Lenient', if set to true, will cause format based failures to be
    ignored. I don't know what the bloody default is, Elasticsearch
    documentation didn't say what it was. Let me know if you figure it out.
-}
newtype Lenient =
  Lenient Bool deriving (Eq, Show, Generic)
newtype Tiebreaker =
  Tiebreaker Double deriving (Eq, Show, Generic)
newtype Boost =
  Boost Double deriving (Eq, Show, Generic)
newtype BoostTerms =
  BoostTerms Double deriving (Eq, Show, Generic)

{-| 'MinimumMatch' controls how many should clauses in the bool query should
     match. Can be an absolute value (2) or a percentage (30%) or a
     combination of both.
-}
newtype MinimumMatch =
  MinimumMatch Int deriving (Eq, Show, Generic)
newtype MinimumMatchText =
  MinimumMatchText Text deriving (Eq, Show)
newtype DisableCoord =
  DisableCoord Bool deriving (Eq, Show, Generic)
newtype IgnoreTermFrequency =
  IgnoreTermFrequency Bool deriving (Eq, Show, Generic)
newtype MinimumTermFrequency =
  MinimumTermFrequency Int deriving (Eq, Show, Generic)
newtype MaxQueryTerms =
  MaxQueryTerms Int deriving (Eq, Show, Generic)
newtype Fuzziness =
  Fuzziness Double deriving (Eq, Show, Generic)

{-| 'PrefixLength' is the prefix length used in queries, defaults to 0. -}
newtype PrefixLength =
  PrefixLength Int deriving (Eq, Show, Generic)
newtype TypeName =
  TypeName Text deriving (Eq, Show, Generic)
newtype PercentMatch =
  PercentMatch Double deriving (Eq, Show, Generic)
newtype StopWord =
  StopWord Text deriving (Eq, Show, Generic)
newtype QueryPath =
  QueryPath Text deriving (Eq, Show, Generic)

{-| Allowing a wildcard at the beginning of a word (eg "*ing") is particularly
    heavy, because all terms in the index need to be examined, just in case
    they match. Leading wildcards can be disabled by setting
    'AllowLeadingWildcard' to false. -}
newtype AllowLeadingWildcard =
  AllowLeadingWildcard     Bool deriving (Eq, Show, Generic)
newtype LowercaseExpanded =
  LowercaseExpanded        Bool deriving (Eq, Show, Generic)
newtype EnablePositionIncrements =
  EnablePositionIncrements Bool deriving (Eq, Show, Generic)

{-| By default, wildcard terms in a query are not analyzed.
    Setting 'AnalyzeWildcard' to true enables best-effort analysis.
-}
newtype AnalyzeWildcard = AnalyzeWildcard Bool deriving (Eq, Show, Generic)

{-| 'GeneratePhraseQueries' defaults to false.
-}
newtype GeneratePhraseQueries =
  GeneratePhraseQueries Bool deriving (Eq, Show, Generic)

{-| 'Locale' is used for string conversions - defaults to ROOT.
-}
newtype Locale        = Locale        Text deriving (Eq, Show, Generic)
newtype MaxWordLength = MaxWordLength Int  deriving (Eq, Show, Generic)
newtype MinWordLength = MinWordLength Int  deriving (Eq, Show, Generic)

{-| 'PhraseSlop' sets the default slop for phrases, 0 means exact
     phrase matches. Default is 0.
-}
newtype PhraseSlop      = PhraseSlop      Int deriving (Eq, Show, Generic)
newtype MinDocFrequency = MinDocFrequency Int deriving (Eq, Show, Generic)
newtype MaxDocFrequency = MaxDocFrequency Int deriving (Eq, Show, Generic)

{-| 'unpackId' is a silly convenience function that gets used once.
-}
unpackId :: DocId -> Text
unpackId (DocId docId) = docId

type TrackSortScores = Bool
newtype From = From Int deriving (Eq, Show, ToJSON)
newtype Size = Size Int deriving (Eq, Show, ToJSON)

data Search = Search { queryBody       :: Maybe Query
                     , filterBody      :: Maybe Filter
                     , sortBody        :: Maybe Sort
                     , aggBody         :: Maybe Aggregations
                     , highlight       :: Maybe Highlights
                       -- default False
                     , trackSortScores :: TrackSortScores
                     , from            :: From
                     , size            :: Size } deriving (Eq, Show)

data Highlights = Highlights { globalsettings  :: Maybe HighlightSettings
                             , highlightFields :: [FieldHighlight]
                             } deriving (Show, Eq)

data FieldHighlight = FieldHighlight FieldName (Maybe HighlightSettings)
                      deriving (Show, Eq)


data HighlightSettings = Plain PlainHighlight
                       | Postings PostingsHighlight
                       | FastVector FastVectorHighlight
                         deriving (Show, Eq)
data PlainHighlight =
    PlainHighlight { plainCommon  :: Maybe CommonHighlight
                   , plainNonPost :: Maybe NonPostings } deriving (Show, Eq)

 -- This requires that index_options are set to 'offset' in the mapping.
data PostingsHighlight = PostingsHighlight (Maybe CommonHighlight) deriving (Show, Eq)

-- This requires that term_vector is set to 'with_positions_offsets' in the mapping.
data FastVectorHighlight =
    FastVectorHighlight { fvCommon          :: Maybe CommonHighlight
                        , fvNonPostSettings :: Maybe NonPostings
                        , boundaryChars     :: Maybe Text
                        , boundaryMaxScan   :: Maybe Int
                        , fragmentOffset    :: Maybe Int
                        , matchedFields     :: [Text]
                        , phraseLimit       :: Maybe Int
                        } deriving (Show, Eq)

data CommonHighlight =
    CommonHighlight { order             :: Maybe Text
                    , forceSource       :: Maybe Bool
                    , tag               :: Maybe HighlightTag
                    , encoder           :: Maybe HighlightEncoder
                    , noMatchSize       :: Maybe Int
                    , highlightQuery    :: Maybe Query
                    , requireFieldMatch :: Maybe Bool
                    } deriving (Show, Eq)

-- Settings that are only applicable to FastVector and Plain highlighters.
data NonPostings =
    NonPostings { fragmentSize      :: Maybe Int
                , numberOfFragments :: Maybe Int} deriving (Show, Eq)

data HighlightEncoder = DefaultEncoder
                      | HTMLEncoder
                      deriving (Show, Eq)

-- NOTE: Should the tags use some kind of HTML type, rather than Text?
data HighlightTag = TagSchema Text
                  | CustomTags ([Text], [Text]) -- Only uses more than the first value in the lists if fvh
                  deriving (Show, Eq)


data Query =
  TermQuery                     Term (Maybe Boost)
  | TermsQuery                  (NonEmpty Term)
  | QueryMatchQuery             MatchQuery
  | QueryMultiMatchQuery        MultiMatchQuery
  | QueryBoolQuery              BoolQuery
  | QueryBoostingQuery          BoostingQuery
  | QueryCommonTermsQuery       CommonTermsQuery
  | ConstantScoreFilter         Filter Boost
  | ConstantScoreQuery          Query Boost
  | QueryDisMaxQuery            DisMaxQuery
  | QueryFilteredQuery          FilteredQuery
  | QueryFuzzyLikeThisQuery     FuzzyLikeThisQuery
  | QueryFuzzyLikeFieldQuery    FuzzyLikeFieldQuery
  | QueryFuzzyQuery             FuzzyQuery
  | QueryHasChildQuery          HasChildQuery
  | QueryHasParentQuery         HasParentQuery
  | IdsQuery                    MappingName [DocId]
  | QueryIndicesQuery           IndicesQuery
  | MatchAllQuery               (Maybe Boost)
  | QueryMoreLikeThisQuery      MoreLikeThisQuery
  | QueryMoreLikeThisFieldQuery MoreLikeThisFieldQuery
  | QueryNestedQuery            NestedQuery
  | QueryPrefixQuery            PrefixQuery
  | QueryQueryStringQuery       QueryStringQuery
  | QuerySimpleQueryStringQuery SimpleQueryStringQuery
  | QueryRangeQuery             RangeQuery
  | QueryRegexpQuery            RegexpQuery
  deriving (Eq, Show)

data RegexpQuery =
  RegexpQuery { regexpQueryField :: FieldName
              , regexpQuery      :: Regexp
              , regexpQueryFlags :: RegexpFlags
              , regexpQueryBoost :: Maybe Boost
              } deriving (Eq, Show)

data RangeQuery =
  RangeQuery { rangeQueryField :: FieldName
             , rangeQueryRange :: RangeValue
             , rangeQueryBoost :: Boost } deriving (Eq, Show)

mkRangeQuery :: FieldName -> RangeValue -> RangeQuery
mkRangeQuery f r = RangeQuery f r (Boost 1.0)

data SimpleQueryStringQuery =
  SimpleQueryStringQuery
    { simpleQueryStringQuery             :: QueryString
    , simpleQueryStringField             :: Maybe FieldOrFields
    , simpleQueryStringOperator          :: Maybe BooleanOperator
    , simpleQueryStringAnalyzer          :: Maybe Analyzer
    , simpleQueryStringFlags             :: Maybe [SimpleQueryFlag]
    , simpleQueryStringLowercaseExpanded :: Maybe LowercaseExpanded
    , simpleQueryStringLocale            :: Maybe Locale
    } deriving (Eq, Show)

data SimpleQueryFlag =
  SimpleQueryAll
  | SimpleQueryNone
  | SimpleQueryAnd
  | SimpleQueryOr
  | SimpleQueryPrefix
  | SimpleQueryPhrase
  | SimpleQueryPrecedence
  | SimpleQueryEscape
  | SimpleQueryWhitespace
  | SimpleQueryFuzzy
  | SimpleQueryNear
  | SimpleQuerySlop deriving (Eq, Show)

-- use_dis_max and tie_breaker when fields are plural?
data QueryStringQuery =
  QueryStringQuery
  { queryStringQuery                    :: QueryString
  , queryStringDefaultField             :: Maybe FieldName
  , queryStringOperator                 :: Maybe BooleanOperator
  , queryStringAnalyzer                 :: Maybe Analyzer
  , queryStringAllowLeadingWildcard     :: Maybe AllowLeadingWildcard
  , queryStringLowercaseExpanded        :: Maybe LowercaseExpanded
  , queryStringEnablePositionIncrements :: Maybe EnablePositionIncrements
  , queryStringFuzzyMaxExpansions       :: Maybe MaxExpansions
  , queryStringFuzziness                :: Maybe Fuzziness
  , queryStringFuzzyPrefixLength        :: Maybe PrefixLength
  , queryStringPhraseSlop               :: Maybe PhraseSlop
  , queryStringBoost                    :: Maybe Boost
  , queryStringAnalyzeWildcard          :: Maybe AnalyzeWildcard
  , queryStringGeneratePhraseQueries    :: Maybe GeneratePhraseQueries
  , queryStringMinimumShouldMatch       :: Maybe MinimumMatch
  , queryStringLenient                  :: Maybe Lenient
  , queryStringLocale                   :: Maybe Locale
  } deriving (Eq, Show)

mkQueryStringQuery :: QueryString -> QueryStringQuery
mkQueryStringQuery qs =
  QueryStringQuery qs Nothing Nothing
  Nothing Nothing Nothing Nothing
  Nothing Nothing Nothing Nothing
  Nothing Nothing Nothing Nothing
  Nothing Nothing

data FieldOrFields = FofField   FieldName
                   | FofFields [FieldName] deriving (Eq, Show)

data PrefixQuery =
  PrefixQuery
  { prefixQueryField       :: FieldName
  , prefixQueryPrefixValue :: Text
  , prefixQueryBoost       :: Maybe Boost } deriving (Eq, Show)

data NestedQuery =
  NestedQuery
  { nestedQueryPath      :: QueryPath
  , nestedQueryScoreType :: ScoreType
  , nestedQuery          :: Query } deriving (Eq, Show)

data MoreLikeThisFieldQuery =
  MoreLikeThisFieldQuery
  { moreLikeThisFieldText            :: Text
  , moreLikeThisFieldFields          :: FieldName
                                        -- default 0.3 (30%)
  , moreLikeThisFieldPercentMatch    :: Maybe PercentMatch
  , moreLikeThisFieldMinimumTermFreq :: Maybe MinimumTermFrequency
  , moreLikeThisFieldMaxQueryTerms   :: Maybe MaxQueryTerms
  , moreLikeThisFieldStopWords       :: Maybe [StopWord]
  , moreLikeThisFieldMinDocFrequency :: Maybe MinDocFrequency
  , moreLikeThisFieldMaxDocFrequency :: Maybe MaxDocFrequency
  , moreLikeThisFieldMinWordLength   :: Maybe MinWordLength
  , moreLikeThisFieldMaxWordLength   :: Maybe MaxWordLength
  , moreLikeThisFieldBoostTerms      :: Maybe BoostTerms
  , moreLikeThisFieldBoost           :: Maybe Boost
  , moreLikeThisFieldAnalyzer        :: Maybe Analyzer
  } deriving (Eq, Show)

data MoreLikeThisQuery =
  MoreLikeThisQuery
  { moreLikeThisText            :: Text
  , moreLikeThisFields          :: Maybe [FieldName]
    -- default 0.3 (30%)
  , moreLikeThisPercentMatch    :: Maybe PercentMatch
  , moreLikeThisMinimumTermFreq :: Maybe MinimumTermFrequency
  , moreLikeThisMaxQueryTerms   :: Maybe MaxQueryTerms
  , moreLikeThisStopWords       :: Maybe [StopWord]
  , moreLikeThisMinDocFrequency :: Maybe MinDocFrequency
  , moreLikeThisMaxDocFrequency :: Maybe MaxDocFrequency
  , moreLikeThisMinWordLength   :: Maybe MinWordLength
  , moreLikeThisMaxWordLength   :: Maybe MaxWordLength
  , moreLikeThisBoostTerms      :: Maybe BoostTerms
  , moreLikeThisBoost           :: Maybe Boost
  , moreLikeThisAnalyzer        :: Maybe Analyzer
  } deriving (Eq, Show)

data IndicesQuery =
  IndicesQuery
  { indicesQueryIndices :: [IndexName]
  , indicesQuery        :: Query
    -- default "all"
  , indicesQueryNoMatch :: Maybe Query } deriving (Eq, Show)

data HasParentQuery =
  HasParentQuery
  { hasParentQueryType      :: TypeName
  , hasParentQuery          :: Query
  , hasParentQueryScoreType :: Maybe ScoreType } deriving (Eq, Show)

data HasChildQuery =
  HasChildQuery
  { hasChildQueryType      :: TypeName
  , hasChildQuery          :: Query
  , hasChildQueryScoreType :: Maybe ScoreType } deriving (Eq, Show)

data ScoreType =
  ScoreTypeMax
  | ScoreTypeSum
  | ScoreTypeAvg
  | ScoreTypeNone deriving (Eq, Show)

data FuzzyQuery =
  FuzzyQuery { fuzzyQueryField         :: FieldName
             , fuzzyQueryValue         :: Text
             , fuzzyQueryPrefixLength  :: PrefixLength
             , fuzzyQueryMaxExpansions :: MaxExpansions
             , fuzzyQueryFuzziness     :: Fuzziness
             , fuzzyQueryBoost         :: Maybe Boost
             } deriving (Eq, Show)

data FuzzyLikeFieldQuery =
  FuzzyLikeFieldQuery
  { fuzzyLikeField                    :: FieldName
    -- anaphora is good for the soul.
  , fuzzyLikeFieldText                :: Text
  , fuzzyLikeFieldMaxQueryTerms       :: MaxQueryTerms
  , fuzzyLikeFieldIgnoreTermFrequency :: IgnoreTermFrequency
  , fuzzyLikeFieldFuzziness           :: Fuzziness
  , fuzzyLikeFieldPrefixLength        :: PrefixLength
  , fuzzyLikeFieldBoost               :: Boost
  , fuzzyLikeFieldAnalyzer            :: Maybe Analyzer
  } deriving (Eq, Show)

data FuzzyLikeThisQuery =
  FuzzyLikeThisQuery
  { fuzzyLikeFields              :: [FieldName]
  , fuzzyLikeText                :: Text
  , fuzzyLikeMaxQueryTerms       :: MaxQueryTerms
  , fuzzyLikeIgnoreTermFrequency :: IgnoreTermFrequency
  , fuzzyLikeFuzziness           :: Fuzziness
  , fuzzyLikePrefixLength        :: PrefixLength
  , fuzzyLikeBoost               :: Boost
  , fuzzyLikeAnalyzer            :: Maybe Analyzer
  } deriving (Eq, Show)

data FilteredQuery =
  FilteredQuery
  { filteredQuery  :: Query
  , filteredFilter :: Filter } deriving (Eq, Show)

data DisMaxQuery =
  DisMaxQuery { disMaxQueries    :: [Query]
                -- default 0.0
              , disMaxTiebreaker :: Tiebreaker
              , disMaxBoost      :: Maybe Boost
              } deriving (Eq, Show)

data MatchQuery =
  MatchQuery { matchQueryField           :: FieldName
             , matchQueryQueryString     :: QueryString
             , matchQueryOperator        :: BooleanOperator
             , matchQueryZeroTerms       :: ZeroTermsQuery
             , matchQueryCutoffFrequency :: Maybe CutoffFrequency
             , matchQueryMatchType       :: Maybe MatchQueryType
             , matchQueryAnalyzer        :: Maybe Analyzer
             , matchQueryMaxExpansions   :: Maybe MaxExpansions
             , matchQueryLenient         :: Maybe Lenient } deriving (Eq, Show)

{-| 'mkMatchQuery' is a convenience function that defaults the less common parameters,
    enabling you to provide only the 'FieldName' and 'QueryString' to make a 'MatchQuery'
-}
mkMatchQuery :: FieldName -> QueryString -> MatchQuery
mkMatchQuery field query = MatchQuery field query Or ZeroTermsNone Nothing Nothing Nothing Nothing Nothing

data MatchQueryType =
  MatchPhrase
  | MatchPhrasePrefix deriving (Eq, Show)

data MultiMatchQuery =
  MultiMatchQuery { multiMatchQueryFields          :: [FieldName]
                  , multiMatchQueryString          :: QueryString
                  , multiMatchQueryOperator        :: BooleanOperator
                  , multiMatchQueryZeroTerms       :: ZeroTermsQuery
                  , multiMatchQueryTiebreaker      :: Maybe Tiebreaker
                  , multiMatchQueryType            :: Maybe MultiMatchQueryType
                  , multiMatchQueryCutoffFrequency :: Maybe CutoffFrequency
                  , multiMatchQueryAnalyzer        :: Maybe Analyzer
                  , multiMatchQueryMaxExpansions   :: Maybe MaxExpansions
                  , multiMatchQueryLenient         :: Maybe Lenient } deriving (Eq, Show)

{-| 'mkMultiMatchQuery' is a convenience function that defaults the less common parameters,
    enabling you to provide only the list of 'FieldName's and 'QueryString' to
    make a 'MultiMatchQuery'.
-}

mkMultiMatchQuery :: [FieldName] -> QueryString -> MultiMatchQuery
mkMultiMatchQuery matchFields query =
  MultiMatchQuery matchFields query
  Or ZeroTermsNone Nothing Nothing Nothing Nothing Nothing Nothing

data MultiMatchQueryType =
  MultiMatchBestFields
  | MultiMatchMostFields
  | MultiMatchCrossFields
  | MultiMatchPhrase
  | MultiMatchPhrasePrefix deriving (Eq, Show)

data BoolQuery =
  BoolQuery { boolQueryMustMatch          :: [Query]
            , boolQueryMustNotMatch       :: [Query]
            , boolQueryShouldMatch        :: [Query]
            , boolQueryMinimumShouldMatch :: Maybe MinimumMatch
            , boolQueryBoost              :: Maybe Boost
            , boolQueryDisableCoord       :: Maybe DisableCoord
            } deriving (Eq, Show)

mkBoolQuery :: [Query] -> [Query] -> [Query] -> BoolQuery
mkBoolQuery must mustNot should =
  BoolQuery must mustNot should Nothing Nothing Nothing

data BoostingQuery =
  BoostingQuery { positiveQuery :: Query
                , negativeQuery :: Query
                , negativeBoost :: Boost } deriving (Eq, Show)

data CommonTermsQuery =
  CommonTermsQuery { commonField              :: FieldName
                   , commonQuery              :: QueryString
                   , commonCutoffFrequency    :: CutoffFrequency
                   , commonLowFreqOperator    :: BooleanOperator
                   , commonHighFreqOperator   :: BooleanOperator
                   , commonMinimumShouldMatch :: Maybe CommonMinimumMatch
                   , commonBoost              :: Maybe Boost
                   , commonAnalyzer           :: Maybe Analyzer
                   , commonDisableCoord       :: Maybe DisableCoord
                   } deriving (Eq, Show)

data CommonMinimumMatch =
    CommonMinimumMatchHighLow MinimumMatchHighLow
  | CommonMinimumMatch        MinimumMatch
  deriving (Eq, Show)

data MinimumMatchHighLow =
  MinimumMatchHighLow { lowFreq  :: MinimumMatch
                      , highFreq :: MinimumMatch } deriving (Eq, Show)

data Filter = AndFilter [Filter] Cache
            | OrFilter  [Filter] Cache
            | NotFilter  Filter  Cache
            | IdentityFilter
            | BoolFilter BoolMatch
            | ExistsFilter FieldName -- always cached
            | GeoBoundingBoxFilter GeoBoundingBoxConstraint
            | GeoDistanceFilter GeoPoint Distance DistanceType OptimizeBbox Cache
            | GeoDistanceRangeFilter GeoPoint DistanceRange
            | GeoPolygonFilter FieldName [LatLon]
            | IdsFilter MappingName [DocId]
            | LimitFilter Int
            | MissingFilter FieldName Existence NullValue
            | PrefixFilter  FieldName PrefixValue Cache
            | QueryFilter   Query Cache
            | RangeFilter   FieldName RangeValue RangeExecution Cache
            | RegexpFilter  FieldName Regexp RegexpFlags CacheName Cache CacheKey
            | TermFilter    Term Cache
              deriving (Eq, Show)

data ZeroTermsQuery = ZeroTermsNone
                    | ZeroTermsAll deriving (Eq, Show)

data RangeExecution = RangeExecutionIndex
                    | RangeExecutionFielddata deriving (Eq, Show)

newtype Regexp = Regexp Text deriving (Eq, Show)

data RegexpFlags = AllRegexpFlags
                 | NoRegexpFlags
                 | SomeRegexpFlags (NonEmpty RegexpFlag) deriving (Eq, Show)

data RegexpFlag = AnyString
                | Automaton
                | Complement
                | Empty
                | Intersection
                | Interval deriving (Eq, Show)

newtype LessThan = LessThan Double deriving (Eq, Show)
newtype LessThanEq = LessThanEq Double deriving (Eq, Show)
newtype GreaterThan = GreaterThan Double deriving (Eq, Show)
newtype GreaterThanEq = GreaterThanEq Double deriving (Eq, Show)

newtype LessThanD = LessThanD UTCTime deriving (Eq, Show)
newtype LessThanEqD = LessThanEqD UTCTime deriving (Eq, Show)
newtype GreaterThanD = GreaterThanD UTCTime deriving (Eq, Show)
newtype GreaterThanEqD = GreaterThanEqD UTCTime deriving (Eq, Show)

data RangeValue = RangeDateLte LessThanEqD
                | RangeDateLt LessThanD
                | RangeDateGte GreaterThanEqD
                | RangeDateGt GreaterThanD
                | RangeDateGtLt GreaterThanD LessThanD
                | RangeDateGteLte GreaterThanEqD LessThanEqD
                | RangeDateGteLt GreaterThanEqD LessThanD
                | RangeDateGtLte GreaterThanD LessThanEqD
                | RangeDoubleLte LessThanEq
                | RangeDoubleLt LessThan
                | RangeDoubleGte GreaterThanEq
                | RangeDoubleGt GreaterThan
                | RangeDoubleGtLt GreaterThan LessThan
                | RangeDoubleGteLte GreaterThanEq LessThanEq
                | RangeDoubleGteLt GreaterThanEq LessThan
                | RangeDoubleGtLte GreaterThan LessThanEq
                deriving (Eq, Show)

rangeValueToPair :: RangeValue -> [Pair]
rangeValueToPair rv = case rv of
  RangeDateLte (LessThanEqD t)                       -> ["lte" .= t]
  RangeDateGte (GreaterThanEqD t)                    -> ["gte" .= t]
  RangeDateLt (LessThanD t)                          -> ["lt"  .= t]
  RangeDateGt (GreaterThanD t)                       -> ["gt"  .= t]
  RangeDateGteLte (GreaterThanEqD l) (LessThanEqD g) -> ["gte" .= l, "lte" .= g]
  RangeDateGtLte (GreaterThanD l) (LessThanEqD g)    -> ["gt"  .= l, "lte" .= g]
  RangeDateGteLt (GreaterThanEqD l) (LessThanD g)    -> ["gte" .= l, "lt"  .= g]
  RangeDateGtLt (GreaterThanD l) (LessThanD g)       -> ["gt"  .= l, "lt"  .= g]
  RangeDoubleLte (LessThanEq t)                      -> ["lte" .= t]
  RangeDoubleGte (GreaterThanEq t)                   -> ["gte" .= t]
  RangeDoubleLt (LessThan t)                         -> ["lt"  .= t]
  RangeDoubleGt (GreaterThan t)                      -> ["gt"  .= t]
  RangeDoubleGteLte (GreaterThanEq l) (LessThanEq g) -> ["gte" .= l, "lte" .= g]
  RangeDoubleGtLte (GreaterThan l) (LessThanEq g)    -> ["gt"  .= l, "lte" .= g]
  RangeDoubleGteLt (GreaterThanEq l) (LessThan g)    -> ["gte" .= l, "lt"  .= g]
  RangeDoubleGtLt (GreaterThan l) (LessThan g)       -> ["gt"  .= l, "lt"  .= g]

data Term = Term { termField :: Text
                 , termValue :: Text } deriving (Eq, Show)

data BoolMatch = MustMatch    Term  Cache
               | MustNotMatch Term  Cache
               | ShouldMatch [Term] Cache deriving (Eq, Show)

-- "memory" or "indexed"
data GeoFilterType = GeoFilterMemory
                   | GeoFilterIndexed deriving (Eq, Show)

data LatLon = LatLon { lat :: Double
                     , lon :: Double } deriving (Eq, Show)

data GeoBoundingBox =
  GeoBoundingBox { topLeft     :: LatLon
                 , bottomRight :: LatLon } deriving (Eq, Show)

data GeoBoundingBoxConstraint =
  GeoBoundingBoxConstraint { geoBBField        :: FieldName
                           , constraintBox     :: GeoBoundingBox
                           , bbConstraintcache :: Cache
                           , geoType           :: GeoFilterType
                           } deriving (Eq, Show)

data GeoPoint =
  GeoPoint { geoField :: FieldName
           , latLon   :: LatLon} deriving (Eq, Show)

data DistanceUnit = Miles
                  | Yards
                  | Feet
                  | Inches
                  | Kilometers
                  | Meters
                  | Centimeters
                  | Millimeters
                  | NauticalMiles deriving (Eq, Show)

data DistanceType = Arc
                  | SloppyArc -- doesn't exist <1.0
                  | Plane deriving (Eq, Show)

data OptimizeBbox = OptimizeGeoFilterType GeoFilterType
                  | NoOptimizeBbox deriving (Eq, Show)

data Distance =
  Distance { coefficient :: Double
           , unit        :: DistanceUnit } deriving (Eq, Show)

data DistanceRange =
  DistanceRange { distanceFrom :: Distance
                , distanceTo   :: Distance } deriving (Eq, Show)

data SearchResult a =
  SearchResult { took         :: Int
               , timedOut     :: Bool
               , shards       :: ShardResult
               , searchHits   :: SearchHits a
               , aggregations :: Maybe AggregationResults } deriving (Eq, Show)

type Score = Maybe Double

data SearchHits a =
  SearchHits { hitsTotal :: Int
             , maxScore  :: Score
             , hits      :: [Hit a] } deriving (Eq, Show)


instance Monoid (SearchHits a) where
  mempty = SearchHits 0 Nothing mempty
  mappend (SearchHits ta ma ha) (SearchHits tb mb hb) =
    SearchHits (ta + tb) (max ma mb) (ha <> hb)


data Hit a =
  Hit { hitIndex     :: IndexName
      , hitType      :: MappingName
      , hitDocId     :: DocId
      , hitScore     :: Score
      , hitSource    :: a
      , hitHighlight :: Maybe HitHighlight } deriving (Eq, Show)

data ShardResult =
  ShardResult { shardTotal       :: Int
              , shardsSuccessful :: Int
              , shardsFailed     :: Int } deriving (Eq, Show, Generic)

type HitHighlight = M.Map Text [Text]

showText :: Show a => a -> Text
showText = T.pack . show

type Aggregations = M.Map Text Aggregation

emptyAggregations :: Aggregations
emptyAggregations = M.empty

mkAggregations :: Text -> Aggregation -> Aggregations
mkAggregations name aggregation = M.insert name aggregation emptyAggregations

data TermOrder = TermOrder{ termSortField :: Text
                          , termSortOrder :: SortOrder } deriving (Eq, Show)

data TermInclusion = TermInclusion Text
                   | TermPattern Text Text deriving (Eq, Show)

data CollectionMode = BreadthFirst
                    | DepthFirst deriving (Eq, Show)

data ExecutionHint = Ordinals
                   | GlobalOrdinals
                   | GlobalOrdinalsHash
                   | GlobalOrdinalsLowCardinality
                   | Map deriving (Eq, Show)

data TimeInterval = Weeks
                  | Days
                  | Hours
                  | Minutes
                  | Seconds deriving (Eq)

data Interval = Year
              | Quarter
              | Month
              | Week
              | Day
              | Hour
              | Minute
              | Second
              | FractionalInterval Float TimeInterval deriving (Eq, Show)

data Aggregation = TermsAgg TermsAggregation
                 | DateHistogramAgg DateHistogramAggregation deriving (Eq, Show)


data TermsAggregation = TermsAggregation { term              :: Either Text Text
                                         , termInclude       :: Maybe TermInclusion
                                         , termExclude       :: Maybe TermInclusion
                                         , termOrder         :: Maybe TermOrder
                                         , termMinDocCount   :: Maybe Int
                                         , termSize          :: Maybe Int
                                         , termShardSize     :: Maybe Int
                                         , termCollectMode   :: Maybe CollectionMode
                                         , termExecutionHint :: Maybe ExecutionHint
                                         , termAggs          :: Maybe Aggregations
                                    } deriving (Eq, Show)

data DateHistogramAggregation = DateHistogramAggregation { dateField      :: FieldName
                                                         , dateInterval   :: Interval
                                                         , dateFormat     :: Maybe Text
                                                         -- pre and post deprecated in 1.5
                                                         , datePreZone    :: Maybe Text
                                                         , datePostZone   :: Maybe Text
                                                         , datePreOffset  :: Maybe Text
                                                         , datePostOffset :: Maybe Text
                                                         , dateAggs       :: Maybe Aggregations
                                                         } deriving (Eq, Show)


mkTermsAggregation :: Text -> TermsAggregation
mkTermsAggregation t = TermsAggregation (Left t) Nothing Nothing Nothing Nothing Nothing Nothing Nothing Nothing Nothing

mkTermsScriptAggregation :: Text -> TermsAggregation
mkTermsScriptAggregation t = TermsAggregation (Right t) Nothing Nothing Nothing Nothing Nothing Nothing Nothing Nothing Nothing

mkDateHistogram :: FieldName -> Interval -> DateHistogramAggregation
mkDateHistogram t i = DateHistogramAggregation t i Nothing Nothing Nothing Nothing Nothing Nothing

instance ToJSON TermOrder where
  toJSON (TermOrder termSortField termSortOrder) = object [termSortField .= termSortOrder]

instance ToJSON TermInclusion where
  toJSON (TermInclusion x) = toJSON x
  toJSON (TermPattern pattern flags) = omitNulls [ "pattern" .= pattern,
                                                     "flags"   .= flags]

instance ToJSON CollectionMode where
  toJSON BreadthFirst = "breadth_first"
  toJSON DepthFirst   = "depth_first"

instance ToJSON ExecutionHint where
  toJSON Ordinals                     = "ordinals"
  toJSON GlobalOrdinals               = "global_ordinals"
  toJSON GlobalOrdinalsHash           = "global_ordinals_hash"
  toJSON GlobalOrdinalsLowCardinality = "global_ordinals_low_cardinality"
  toJSON Map                          = "map"

instance ToJSON Interval where
  toJSON Year = "year"
  toJSON Quarter = "quarter"
  toJSON Month = "month"
  toJSON Week = "week"
  toJSON Day = "day"
  toJSON Hour = "hour"
  toJSON Minute = "minute"
  toJSON Second = "second"
  toJSON (FractionalInterval fraction interval) = toJSON $ show fraction ++ show interval

instance Show TimeInterval where
  show Weeks    = "w"
  show Days     = "d"
  show Hours    = "h"
  show Minutes  = "m"
  show Seconds  = "s"

instance ToJSON Aggregation where
  toJSON (TermsAgg (TermsAggregation term include exclude order minDocCount size shardSize collectMode executionHint termAggs)) =
    omitNulls ["terms" .= omitNulls [ toJSON' term,
                                      "include"        .= include,
                                      "exclude"        .= exclude,
                                      "order"          .= order,
                                      "min_doc_count"  .= minDocCount,
                                      "size"           .= size,
                                      "shard_size"     .= shardSize,
                                      "collect_mode"   .= collectMode,
                                      "execution_hint" .= executionHint
                                    ],
               "aggs"  .= termAggs ]
    where
      toJSON' x = case x of { Left y -> "field" .= y;  Right y -> "script" .= y }

  toJSON (DateHistogramAgg (DateHistogramAggregation field interval format preZone postZone preOffset postOffset dateHistoAggs)) =
    omitNulls ["date_histogram" .= omitNulls [ "field"       .= field,
                                               "interval"    .= interval,
                                               "format"      .= format,
                                               "pre_zone"    .= preZone,
                                               "post_zone"   .= postZone,
                                               "pre_offset"  .= preOffset,
                                               "post_offset" .= postOffset
                                             ],
               "aggs"           .= dateHistoAggs ]

type AggregationResults = M.Map Text Value

class BucketAggregation a where
  key :: a -> Text
  docCount :: a -> Int
  aggs :: a -> Maybe AggregationResults


data Bucket a = Bucket { buckets :: [a]} deriving (Show)

data TermsResult = TermsResult { termKey       :: Text
                               , termsDocCount :: Int
                               , termsAggs     :: Maybe AggregationResults } deriving (Show)

data DateHistogramResult = DateHistogramResult { dateKey           :: Int
                                               , dateKeyStr        :: Maybe Text
                                               , dateDocCount      :: Int
                                               , dateHistogramAggs :: Maybe AggregationResults } deriving (Show)

toTerms :: Text -> AggregationResults ->  Maybe (Bucket TermsResult)
toTerms t a = M.lookup t a >>= deserialize
  where deserialize = parseMaybe parseJSON

toDateHistogram :: Text -> AggregationResults -> Maybe (Bucket DateHistogramResult)
toDateHistogram t a = M.lookup t a >>= deserialize
  where deserialize = parseMaybe parseJSON

instance BucketAggregation TermsResult where
  key = termKey
  docCount = termsDocCount
  aggs = termsAggs

instance BucketAggregation DateHistogramResult where
  key = showText . dateKey
  docCount = dateDocCount
  aggs = dateHistogramAggs

instance (FromJSON a, BucketAggregation a) => FromJSON (Bucket a) where
  parseJSON (Object v) = Bucket <$>
                         v .: "buckets"
  parseJSON _ = mempty

instance FromJSON TermsResult where
  parseJSON (Object v) = TermsResult <$>
                         v .:   "key"       <*>
                         v .:   "doc_count" <*>
                         v .:?  "aggregations"
  parseJSON _ = mempty

instance FromJSON DateHistogramResult where
  parseJSON (Object v) = DateHistogramResult   <$>
                         v .:  "key"           <*>
                         v .:? "key_as_string" <*>
                         v .:  "doc_count"     <*>
                         v .:? "aggregations"
  parseJSON _ = mempty

instance Monoid Filter where
  mempty = IdentityFilter
  mappend a b = AndFilter [a, b] defaultCache

instance Seminearring Filter where
  a <||> b = OrFilter [a, b] defaultCache

instance ToJSON Filter where
  toJSON (AndFilter filters cache) =
    object ["and" .=
            object [ "filters" .= fmap toJSON filters
                   , "_cache"  .= cache]]

  toJSON (OrFilter filters cache) =
    object ["or" .=
            object [ "filters" .= fmap toJSON filters
                   , "_cache"  .= cache]]

  toJSON (NotFilter notFilter cache) =
    object ["not" .=
            object ["filter"  .= notFilter
                   , "_cache" .= cache]]

  toJSON (IdentityFilter) =
    object ["match_all" .= object []]

  toJSON (TermFilter (Term termFilterField termFilterValue) cache) =
    object ["term" .= object base]
    where base = [termFilterField .= termFilterValue,
                  "_cache"        .= cache]

  toJSON (ExistsFilter (FieldName fieldName)) =
    object ["exists"  .= object
            ["field"  .= fieldName]]

  toJSON (BoolFilter boolMatch) =
    object ["bool"    .= boolMatch]

  toJSON (GeoBoundingBoxFilter bbConstraint) =
    object ["geo_bounding_box" .= bbConstraint]

  toJSON (GeoDistanceFilter (GeoPoint (FieldName distanceGeoField) geoDistLatLon)
          distance distanceType optimizeBbox cache) =
    object ["geo_distance" .=
            object ["distance" .= distance
                   , "distance_type" .= distanceType
                   , "optimize_bbox" .= optimizeBbox
                   , distanceGeoField .= geoDistLatLon
                   , "_cache" .= cache]]

  toJSON (GeoDistanceRangeFilter (GeoPoint (FieldName gddrField) drLatLon)
          (DistanceRange geoDistRangeDistFrom drDistanceTo)) =
    object ["geo_distance_range" .=
            object ["from" .= geoDistRangeDistFrom
                   , "to"  .= drDistanceTo
                   , gddrField .= drLatLon]]

  toJSON (GeoPolygonFilter (FieldName geoPolygonFilterField) latLons) =
    object ["geo_polygon" .=
            object [geoPolygonFilterField .=
                    object ["points" .= fmap toJSON latLons]]]

  toJSON (IdsFilter (MappingName mappingName) values) =
    object ["ids" .=
            object ["type" .= mappingName
                   , "values" .= fmap unpackId values]]

  toJSON (LimitFilter limit) =
    object ["limit" .= object ["value" .= limit]]

  toJSON (MissingFilter (FieldName fieldName) (Existence existence) (NullValue nullValue)) =
    object ["missing" .=
            object ["field"       .= fieldName
                   , "existence"  .= existence
                   , "null_value" .= nullValue]]

  toJSON (PrefixFilter (FieldName fieldName) fieldValue cache) =
    object ["prefix" .=
            object [fieldName .= fieldValue
                   , "_cache" .= cache]]

  toJSON (QueryFilter query False) =
    object ["query" .= toJSON query ]
  toJSON (QueryFilter query True) =
    object ["fquery" .=
            object [ "query"  .= toJSON query
                   , "_cache" .= True ]]

  toJSON (RangeFilter (FieldName fieldName) rangeValue rangeExecution cache) =
    object ["range" .=
            object [ fieldName .= object (rangeValueToPair rangeValue)
                   , "execution" .= rangeExecution
                   , "_cache" .= cache]]

  toJSON (RegexpFilter (FieldName fieldName)
          (Regexp regexText) flags (CacheName cacheName) cache (CacheKey cacheKey)) =
    object ["regexp" .=
            object [fieldName .=
                    object ["value"  .= regexText
                           , "flags" .= flags]
                   , "_name"      .= cacheName
                   , "_cache"     .= cache
                   , "_cache_key" .= cacheKey]]

instance ToJSON GeoPoint where
  toJSON (GeoPoint (FieldName geoPointField) geoPointLatLon) =
    object [ geoPointField  .= geoPointLatLon ]


instance ToJSON Query where
  toJSON (TermQuery (Term termQueryField termQueryValue) boost) =
    object [ "term" .=
             object [termQueryField .= object merged]]
    where
      base = [ "value" .= termQueryValue ]
      boosted = maybe [] (return . ("boost" .=)) boost
      merged = mappend base boosted

  toJSON (TermsQuery terms) =
    object [ "terms" .= object conjoined ]
    where conjoined = [ getTermsField terms .=
                        fmap (toJSON . getTermValue) (toList terms)]
          getTermsField ((Term f _ ) :| _) = f
          getTermValue (Term _ v) = v
  toJSON (IdsQuery idsQueryMappingName docIds) =
    object [ "ids" .= object conjoined ]
    where conjoined = [ "type"   .= idsQueryMappingName
                      , "values" .= fmap toJSON docIds ]

  toJSON (QueryQueryStringQuery qQueryStringQuery) =
    object [ "query_string" .= qQueryStringQuery ]

  toJSON (QueryMatchQuery matchQuery) =
    object [ "match" .= matchQuery ]

  toJSON (QueryMultiMatchQuery multiMatchQuery) =
      toJSON multiMatchQuery

  toJSON (QueryBoolQuery boolQuery) =
    object [ "bool" .= boolQuery ]

  toJSON (QueryBoostingQuery boostingQuery) =
    object [ "boosting" .= boostingQuery ]

  toJSON (QueryCommonTermsQuery commonTermsQuery) =
    object [ "common" .= commonTermsQuery ]

  toJSON (ConstantScoreFilter csFilter boost) =
    object [ "constant_score" .= csFilter
           , "boost" .= boost]

  toJSON (ConstantScoreQuery query boost) =
    object [ "constant_score" .= query
           , "boost"          .= boost]

  toJSON (QueryDisMaxQuery disMaxQuery) =
    object [ "dis_max" .= disMaxQuery ]

  toJSON (QueryFilteredQuery qFilteredQuery) =
    object [ "filtered" .= qFilteredQuery ]

  toJSON (QueryFuzzyLikeThisQuery fuzzyQuery) =
    object [ "fuzzy_like_this" .= fuzzyQuery ]

  toJSON (QueryFuzzyLikeFieldQuery fuzzyFieldQuery) =
    object [ "fuzzy_like_this_field" .= fuzzyFieldQuery ]

  toJSON (QueryFuzzyQuery fuzzyQuery) =
    object [ "fuzzy" .= fuzzyQuery ]

  toJSON (QueryHasChildQuery childQuery) =
    object [ "has_child" .= childQuery ]

  toJSON (QueryHasParentQuery parentQuery) =
    object [ "has_parent" .= parentQuery ]

  toJSON (QueryIndicesQuery qIndicesQuery) =
    object [ "indices" .= qIndicesQuery ]

  toJSON (MatchAllQuery boost) =
    object [ "match_all" .= omitNulls [ "boost" .= boost ] ]

  toJSON (QueryMoreLikeThisQuery query) =
    object [ "more_like_this" .= query ]

  toJSON (QueryMoreLikeThisFieldQuery query) =
    object [ "more_like_this_field" .= query ]

  toJSON (QueryNestedQuery query) =
    object [ "nested" .= query ]

  toJSON (QueryPrefixQuery query) =
    object [ "prefix" .= query ]

  toJSON (QueryRangeQuery query) =
    object [ "range"  .= query ]

  toJSON (QueryRegexpQuery query) =
    object [ "regexp" .= query ]

  toJSON (QuerySimpleQueryStringQuery query) =
    object [ "simple_query_string" .= query ]


omitNulls :: [(Text, Value)] -> Value
omitNulls = object . filter notNull where
  notNull (_, Null)      = False
  notNull (_, Array a) = (not . V.null) a
  notNull _              = True


instance ToJSON SimpleQueryStringQuery where
  toJSON SimpleQueryStringQuery {..} =
    omitNulls (base ++ maybeAdd)
    where base = [ "query" .= simpleQueryStringQuery ]
          maybeAdd = [ "fields" .= simpleQueryStringField
                     , "default_operator" .= simpleQueryStringOperator
                     , "analyzer" .= simpleQueryStringAnalyzer
                     , "flags" .= simpleQueryStringFlags
                     , "lowercase_expanded_terms" .= simpleQueryStringLowercaseExpanded
                     , "locale" .= simpleQueryStringLocale ]


instance ToJSON FieldOrFields where
  toJSON (FofField fieldName) =
    toJSON fieldName
  toJSON (FofFields fieldNames) =
    toJSON fieldNames

instance ToJSON SimpleQueryFlag where
  toJSON SimpleQueryAll        = "ALL"
  toJSON SimpleQueryNone       = "NONE"
  toJSON SimpleQueryAnd        = "AND"
  toJSON SimpleQueryOr         = "OR"
  toJSON SimpleQueryPrefix     = "PREFIX"
  toJSON SimpleQueryPhrase     = "PHRASE"
  toJSON SimpleQueryPrecedence = "PRECEDENCE"
  toJSON SimpleQueryEscape     = "ESCAPE"
  toJSON SimpleQueryWhitespace = "WHITESPACE"
  toJSON SimpleQueryFuzzy      = "FUZZY"
  toJSON SimpleQueryNear       = "NEAR"
  toJSON SimpleQuerySlop       = "SLOP"


instance ToJSON RegexpQuery where
  toJSON (RegexpQuery (FieldName rqQueryField)
          (Regexp regexpQueryQuery) rqQueryFlags
          rqQueryBoost) =
   object [ rqQueryField .= omitNulls base ]
   where base = [ "value" .= regexpQueryQuery
                , "flags" .= rqQueryFlags
                , "boost" .= rqQueryBoost ]


instance ToJSON QueryStringQuery where
  toJSON (QueryStringQuery qsQueryString
          qsDefaultField qsOperator
          qsAnalyzer qsAllowWildcard
          qsLowercaseExpanded  qsEnablePositionIncrements
          qsFuzzyMaxExpansions qsFuzziness
          qsFuzzyPrefixLength qsPhraseSlop
          qsBoost qsAnalyzeWildcard
          qsGeneratePhraseQueries qsMinimumShouldMatch
          qsLenient qsLocale) =
    omitNulls base
    where
      base = [ "query" .= qsQueryString
             , "default_field" .= qsDefaultField
             , "default_operator" .= qsOperator
             , "analyzer" .= qsAnalyzer
             , "allow_leading_wildcard" .= qsAllowWildcard
             , "lowercase_expanded_terms" .= qsLowercaseExpanded
             , "enable_position_increments" .= qsEnablePositionIncrements
             , "fuzzy_max_expansions" .= qsFuzzyMaxExpansions
             , "fuzziness" .= qsFuzziness
             , "fuzzy_prefix_length" .= qsFuzzyPrefixLength
             , "phrase_slop" .= qsPhraseSlop
             , "boost" .= qsBoost
             , "analyze_wildcard" .= qsAnalyzeWildcard
             , "auto_generate_phrase_queries" .= qsGeneratePhraseQueries
             , "minimum_should_match" .= qsMinimumShouldMatch
             , "lenient" .= qsLenient
             , "locale" .= qsLocale ]


instance ToJSON RangeQuery where
  toJSON (RangeQuery (FieldName fieldName) range boost) =
    object [ fieldName .= conjoined ]
    where conjoined = [ "boost" .= boost ] ++ (rangeValueToPair range)


instance ToJSON PrefixQuery where
  toJSON (PrefixQuery (FieldName fieldName) queryValue boost) =
    object [ fieldName .= omitNulls base ]
    where base = [ "value" .= queryValue
                 , "boost" .= boost ]


instance ToJSON NestedQuery where
  toJSON (NestedQuery nqPath nqScoreType nqQuery) =
    object [ "path"       .= nqPath
           , "score_mode" .= nqScoreType
           , "query"      .= nqQuery ]


instance ToJSON MoreLikeThisFieldQuery where
  toJSON (MoreLikeThisFieldQuery text (FieldName fieldName)
          percent mtf mqt stopwords mindf maxdf
          minwl maxwl boostTerms boost analyzer) =
    object [ fieldName .= omitNulls base ]
    where base = [ "like_text" .= text
                 , "percent_terms_to_match" .= percent
                 , "min_term_freq" .= mtf
                 , "max_query_terms" .= mqt
                 , "stop_words" .= stopwords
                 , "min_doc_freq" .= mindf
                 , "max_doc_freq" .= maxdf
                 , "min_word_length" .= minwl
                 , "max_word_length" .= maxwl
                 , "boost_terms" .= boostTerms
                 , "boost" .= boost
                 , "analyzer" .= analyzer ]


instance ToJSON MoreLikeThisQuery where
  toJSON (MoreLikeThisQuery text fields percent
          mtf mqt stopwords mindf maxdf
          minwl maxwl boostTerms boost analyzer) =
    omitNulls base
    where base = [ "like_text" .= text
                 , "fields" .= fields
                 , "percent_terms_to_match" .= percent
                 , "min_term_freq" .= mtf
                 , "max_query_terms" .= mqt
                 , "stop_words" .= stopwords
                 , "min_doc_freq" .= mindf
                 , "max_doc_freq" .= maxdf
                 , "min_word_length" .= minwl
                 , "max_word_length" .= maxwl
                 , "boost_terms" .= boostTerms
                 , "boost" .= boost
                 , "analyzer" .= analyzer ]


instance ToJSON IndicesQuery where
  toJSON (IndicesQuery indices query noMatch) =
    omitNulls [ "indices" .= indices
              , "no_match_query" .= noMatch
              , "query" .= query ]


instance ToJSON HasParentQuery where
  toJSON (HasParentQuery queryType query scoreType) =
    omitNulls [ "parent_type" .= queryType
              , "score_type" .= scoreType
              , "query" .= query ]


instance ToJSON HasChildQuery where
  toJSON (HasChildQuery queryType query scoreType) =
    omitNulls [ "query" .= query
              , "score_type" .= scoreType
              , "type"  .= queryType ]


instance ToJSON FuzzyQuery where
  toJSON (FuzzyQuery (FieldName fieldName) queryText
          prefixLength maxEx fuzziness boost) =
    object [ fieldName .= omitNulls base ]
    where base = [ "value"          .= queryText
                 , "fuzziness"      .= fuzziness
                 , "prefix_length"  .= prefixLength
                 , "boost" .= boost
                 , "max_expansions" .= maxEx ]


instance ToJSON FuzzyLikeFieldQuery where
  toJSON (FuzzyLikeFieldQuery (FieldName fieldName)
          fieldText maxTerms ignoreFreq fuzziness prefixLength
          boost analyzer) =
    object [ fieldName .=
             omitNulls [ "like_text"       .= fieldText
                       , "max_query_terms" .= maxTerms
                       , "ignore_tf"       .= ignoreFreq
                       , "fuzziness"       .= fuzziness
                       , "prefix_length"   .= prefixLength
                       , "analyzer" .= analyzer
                       , "boost"           .= boost ]]


instance ToJSON FuzzyLikeThisQuery where
  toJSON (FuzzyLikeThisQuery fields text maxTerms
          ignoreFreq fuzziness prefixLength boost analyzer) =
    omitNulls base
    where base = [ "fields"          .= fields
                 , "like_text"       .= text
                 , "max_query_terms" .= maxTerms
                 , "ignore_tf"       .= ignoreFreq
                 , "fuzziness"       .= fuzziness
                 , "prefix_length"   .= prefixLength
                 , "analyzer"        .= analyzer
                 , "boost"           .= boost ]


instance ToJSON FilteredQuery where
  toJSON (FilteredQuery query fFilter) =
    object [ "query"  .= query
           , "filter" .= fFilter ]


instance ToJSON DisMaxQuery where
  toJSON (DisMaxQuery queries tiebreaker boost) =
    omitNulls base
    where base = [ "queries"     .= queries
                 , "boost"       .= boost
                 , "tie_breaker" .= tiebreaker ]


instance ToJSON CommonTermsQuery where
  toJSON (CommonTermsQuery (FieldName fieldName)
          (QueryString query) cf lfo hfo msm
          boost analyzer disableCoord) =
    object [fieldName .= omitNulls base ]
    where base = [ "query"              .= query
                 , "cutoff_frequency"   .= cf
                 , "low_freq_operator"  .= lfo
                 , "minimum_should_match" .= msm
                 , "boost" .= boost
                 , "analyzer" .= analyzer
                 , "disable_coord" .= disableCoord
                 , "high_freq_operator" .= hfo ]


instance ToJSON CommonMinimumMatch where
  toJSON (CommonMinimumMatch mm) = toJSON mm
  toJSON (CommonMinimumMatchHighLow (MinimumMatchHighLow lowF highF)) =
    object [ "low_freq"  .= lowF
           , "high_freq" .= highF ]

instance ToJSON BoostingQuery where
  toJSON (BoostingQuery bqPositiveQuery bqNegativeQuery bqNegativeBoost) =
    object [ "positive"       .= bqPositiveQuery
           , "negative"       .= bqNegativeQuery
           , "negative_boost" .= bqNegativeBoost ]


instance ToJSON BoolQuery where
  toJSON (BoolQuery mustM notM shouldM bqMin boost disableCoord) =
    omitNulls base
    where base = [ "must" .= mustM
                 , "must_not" .= notM
                 , "should" .= shouldM
                 , "minimum_should_match" .= bqMin
                 , "boost" .= boost
                 , "disable_coord" .= disableCoord ]


instance ToJSON MatchQuery where
  toJSON (MatchQuery (FieldName fieldName)
          (QueryString mqQueryString) booleanOperator
          zeroTermsQuery cutoffFrequency matchQueryType
          analyzer maxExpansions lenient) =
    object [ fieldName .= omitNulls base ]
    where base = [ "query" .= mqQueryString
                 , "operator" .= booleanOperator
                 , "zero_terms_query" .= zeroTermsQuery
                 , "cutoff_frequency" .= cutoffFrequency
                 , "type" .= matchQueryType
                 , "analyzer" .= analyzer
                 , "max_expansions" .= maxExpansions
                 , "lenient" .= lenient ]


instance ToJSON MultiMatchQuery where
  toJSON (MultiMatchQuery fields (QueryString query) boolOp
          ztQ tb mmqt cf analyzer maxEx lenient) =
    object ["multi_match" .= omitNulls base]
    where base = [ "fields" .= fmap toJSON fields
                 , "query" .= query
                 , "operator" .= boolOp
                 , "zero_terms_query" .= ztQ
                 , "tiebreaker" .= tb
                 , "type" .= mmqt
                 , "cutoff_frequency" .= cf
                 , "analyzer" .= analyzer
                 , "max_expansions" .= maxEx
                 , "lenient" .= lenient ]


instance ToJSON MultiMatchQueryType where
  toJSON MultiMatchBestFields = "best_fields"
  toJSON MultiMatchMostFields = "most_fields"
  toJSON MultiMatchCrossFields = "cross_fields"
  toJSON MultiMatchPhrase = "phrase"
  toJSON MultiMatchPhrasePrefix = "phrase_prefix"

instance ToJSON BooleanOperator where
  toJSON And = String "and"
  toJSON Or = String "or"

instance ToJSON ZeroTermsQuery where
  toJSON ZeroTermsNone = String "none"
  toJSON ZeroTermsAll  = String "all"

instance ToJSON MatchQueryType where
  toJSON MatchPhrase = "phrase"
  toJSON MatchPhrasePrefix = "phrase_prefix"

instance ToJSON FieldName where
  toJSON (FieldName fieldName) = String fieldName

instance ToJSON ReplicaCount
instance ToJSON ShardCount
instance ToJSON CutoffFrequency
instance ToJSON Analyzer
instance ToJSON MaxExpansions
instance ToJSON Lenient
instance ToJSON Boost
instance ToJSON Version
instance ToJSON Tiebreaker
instance ToJSON MinimumMatch
instance ToJSON DisableCoord
instance ToJSON PrefixLength
instance ToJSON Fuzziness
instance ToJSON IgnoreTermFrequency
instance ToJSON MaxQueryTerms
instance ToJSON TypeName
instance ToJSON IndexName
instance ToJSON BoostTerms
instance ToJSON MaxWordLength
instance ToJSON MinWordLength
instance ToJSON MaxDocFrequency
instance ToJSON MinDocFrequency
instance ToJSON PhraseSlop
instance ToJSON StopWord
instance ToJSON QueryPath
instance ToJSON MinimumTermFrequency
instance ToJSON PercentMatch
instance ToJSON MappingName
instance ToJSON DocId
instance ToJSON QueryString
instance ToJSON AllowLeadingWildcard
instance ToJSON LowercaseExpanded
instance ToJSON AnalyzeWildcard
instance ToJSON GeneratePhraseQueries
instance ToJSON Locale
instance ToJSON EnablePositionIncrements
instance FromJSON Version
instance FromJSON IndexName
instance FromJSON MappingName
instance FromJSON DocId


instance FromJSON Status where
  parseJSON (Object v) = Status <$>
                         v .:? "ok" <*>
                         v .: "status" <*>
                         v .: "name" <*>
                         v .: "version" <*>
                         v .: "tagline"
  parseJSON _          = empty


instance ToJSON IndexSettings where
  toJSON (IndexSettings s r) = object ["settings" .= object ["shards" .= s, "replicas" .= r]]


instance (FromJSON a) => FromJSON (EsResult a) where
  parseJSON (Object v) = EsResult <$>
                         v .:  "_index"   <*>
                         v .:  "_type"    <*>
                         v .:  "_id"      <*>
                         v .:  "_version" <*>
                         v .:? "found"    <*>
                         v .:  "_source"
  parseJSON _          = empty


instance ToJSON Search where
  toJSON (Search query sFilter sort searchAggs highlight sTrackSortScores sFrom sSize) =
    omitNulls [ "query"        .= query
              , "filter"       .= sFilter
              , "sort"         .= sort
              , "aggregations" .= searchAggs
              , "highlight"    .= highlight
              , "from"         .= sFrom
              , "size"         .= sSize
              , "track_scores" .= sTrackSortScores]


instance ToJSON FieldHighlight where
    toJSON (FieldHighlight (FieldName fName) (Just fSettings)) =
        object [ fName .= fSettings ]
    toJSON (FieldHighlight (FieldName fName) Nothing) =
        object [ fName .= emptyObject ]

instance ToJSON Highlights where
    toJSON (Highlights global fields) =
        omitNulls (("fields" .= fields)
                  : highlightSettingsPairs global)

instance ToJSON HighlightSettings where
    toJSON hs = omitNulls (highlightSettingsPairs (Just hs))

highlightSettingsPairs :: Maybe HighlightSettings -> [Pair]
highlightSettingsPairs Nothing = []
highlightSettingsPairs (Just (Plain plh)) = plainHighPairs (Just plh)
highlightSettingsPairs (Just (Postings ph)) = postHighPairs (Just ph)
highlightSettingsPairs (Just (FastVector fvh)) = fastVectorHighPairs (Just fvh)


plainHighPairs :: Maybe PlainHighlight -> [Pair]
plainHighPairs Nothing = []
plainHighPairs (Just (PlainHighlight plCom plNonPost)) =
    [ "type" .= String "plain"]
    ++ commonHighlightPairs plCom
    ++ nonPostingsToPairs plNonPost

postHighPairs :: Maybe PostingsHighlight -> [Pair]
postHighPairs Nothing = []
postHighPairs (Just (PostingsHighlight pCom)) =
    ("type" .= String "postings")
    : commonHighlightPairs pCom

fastVectorHighPairs :: Maybe FastVectorHighlight -> [Pair]
fastVectorHighPairs Nothing = []
fastVectorHighPairs (Just
                     (FastVectorHighlight fvCom fvNonPostSettings fvBoundChars
                                          fvBoundMaxScan fvFragOff fvMatchedFields
                                          fvPhraseLim)) =
                        [ "type" .= String "fvh"
                        , "boundary_chars" .= fvBoundChars
                        , "boundary_max_scan" .= fvBoundMaxScan
                        , "fragment_offset" .= fvFragOff
                        , "matched_fields" .= fvMatchedFields
                        , "phraseLimit" .= fvPhraseLim]
                        ++ commonHighlightPairs fvCom
                        ++ nonPostingsToPairs fvNonPostSettings

commonHighlightPairs :: Maybe CommonHighlight -> [Pair]
commonHighlightPairs Nothing = []
commonHighlightPairs (Just (CommonHighlight chScore chForceSource chTag chEncoder
                                      chNoMatchSize chHighlightQuery
                                      chRequireFieldMatch)) =
    [ "order" .= chScore
    , "force_source" .= chForceSource
    , "encoder" .= chEncoder
    , "no_match_size" .= chNoMatchSize
    , "highlight_query" .= chHighlightQuery
    , "require_fieldMatch" .= chRequireFieldMatch]
    ++ highlightTagToPairs chTag


nonPostingsToPairs :: Maybe NonPostings -> [Pair]
nonPostingsToPairs Nothing = []
nonPostingsToPairs (Just (NonPostings npFragSize npNumOfFrags)) =
    [ "fragment_size" .= npFragSize
    , "number_of_fragments" .= npNumOfFrags]



instance ToJSON HighlightEncoder where
    toJSON DefaultEncoder = String "default"
    toJSON HTMLEncoder    = String "html"

highlightTagToPairs :: Maybe HighlightTag -> [Pair]
highlightTagToPairs (Just (TagSchema _))            = [ "scheme"    .=  String "default"]
highlightTagToPairs (Just (CustomTags (pre, post))) = [ "pre_tags"  .= pre
                                                      , "post_tags" .= post]
highlightTagToPairs Nothing = []

instance ToJSON SortSpec where
  toJSON (DefaultSortSpec
          (DefaultSort (FieldName dsSortFieldName) dsSortOrder dsIgnoreUnmapped
           dsSortMode dsMissingSort dsNestedFilter)) =
    object [dsSortFieldName .= omitNulls base] where
      base = [ "order" .= dsSortOrder
             , "ignore_unmapped" .= dsIgnoreUnmapped
             , "mode" .= dsSortMode
             , "missing" .= dsMissingSort
             , "nested_filter" .= dsNestedFilter ]

  toJSON (GeoDistanceSortSpec gdsSortOrder (GeoPoint (FieldName field) gdsLatLon) units) =
    object [ "unit" .= units
           , field .= gdsLatLon
           , "order" .= gdsSortOrder ]


instance ToJSON SortOrder where
  toJSON Ascending  = String "asc"
  toJSON Descending = String "desc"


instance ToJSON SortMode where
  toJSON SortMin = String "min"
  toJSON SortMax = String "max"
  toJSON SortSum = String "sum"
  toJSON SortAvg = String "avg"


instance ToJSON Missing where
  toJSON LastMissing = String "_last"
  toJSON FirstMissing = String "_first"
  toJSON (CustomMissing txt) = String txt


instance ToJSON ScoreType where
  toJSON ScoreTypeMax  = "max"
  toJSON ScoreTypeAvg  = "avg"
  toJSON ScoreTypeSum  = "sum"
  toJSON ScoreTypeNone = "none"


instance ToJSON Distance where
  toJSON (Distance dCoefficient dUnit) =
    String boltedTogether where
      coefText = showText dCoefficient
      (String unitText) = toJSON dUnit
      boltedTogether = mappend coefText unitText


instance ToJSON DistanceUnit where
  toJSON Miles         = String "mi"
  toJSON Yards         = String "yd"
  toJSON Feet          = String "ft"
  toJSON Inches        = String "in"
  toJSON Kilometers    = String "km"
  toJSON Meters        = String "m"
  toJSON Centimeters   = String "cm"
  toJSON Millimeters   = String "mm"
  toJSON NauticalMiles = String "nmi"


instance ToJSON DistanceType where
  toJSON Arc       = String "arc"
  toJSON SloppyArc = String "sloppy_arc"
  toJSON Plane     = String "plane"


instance ToJSON OptimizeBbox where
  toJSON NoOptimizeBbox = String "none"
  toJSON (OptimizeGeoFilterType gft) = toJSON gft


instance ToJSON GeoBoundingBoxConstraint where
  toJSON (GeoBoundingBoxConstraint
          (FieldName gbbcGeoBBField) gbbcConstraintBox cache type') =
    object [gbbcGeoBBField .= gbbcConstraintBox
           , "_cache"  .= cache
           , "type" .= type']


instance ToJSON GeoFilterType where
  toJSON GeoFilterMemory  = String "memory"
  toJSON GeoFilterIndexed = String "indexed"


instance ToJSON GeoBoundingBox where
  toJSON (GeoBoundingBox gbbTopLeft gbbBottomRight) =
    object ["top_left"      .= gbbTopLeft
           , "bottom_right" .= gbbBottomRight]


instance ToJSON LatLon where
  toJSON (LatLon lLat lLon) =
    object ["lat"  .= lLat
           , "lon" .= lLon]


-- index for smaller ranges, fielddata for longer ranges
instance ToJSON RangeExecution where
  toJSON RangeExecutionIndex     = "index"
  toJSON RangeExecutionFielddata = "fielddata"


instance ToJSON RegexpFlags where
  toJSON AllRegexpFlags              = String "ALL"
  toJSON NoRegexpFlags               = String "NONE"
  toJSON (SomeRegexpFlags (h :| fs)) = String $ T.intercalate "|" flagStrs
    where flagStrs             = map flagStr . nub $ h:fs
          flagStr AnyString    = "ANYSTRING"
          flagStr Automaton    = "AUTOMATON"
          flagStr Complement   = "COMPLEMENT"
          flagStr Empty        = "EMPTY"
          flagStr Intersection = "INTERSECTION"
          flagStr Interval     = "INTERVAL"

instance ToJSON Term where
  toJSON (Term field value) = object ["term" .= object
                                      [field .= value]]


instance ToJSON BoolMatch where
  toJSON (MustMatch    term  cache) = object ["must"     .= term,
                                              "_cache" .= cache]
  toJSON (MustNotMatch term  cache) = object ["must_not" .= term,
                                              "_cache" .= cache]
  toJSON (ShouldMatch  terms cache) = object ["should"   .= fmap toJSON terms,
                                              "_cache" .= cache]


instance (FromJSON a) => FromJSON (SearchResult a) where
  parseJSON (Object v) = SearchResult <$>
                         v .:  "took"         <*>
                         v .:  "timed_out"    <*>
                         v .:  "_shards"      <*>
                         v .:  "hits"         <*>
                         v .:? "aggregations"
  parseJSON _          = empty

instance (FromJSON a) => FromJSON (SearchHits a) where
  parseJSON (Object v) = SearchHits <$>
                         v .: "total"     <*>
                         v .: "max_score" <*>
                         v .: "hits"
  parseJSON _          = empty

instance (FromJSON a) => FromJSON (Hit a) where
  parseJSON (Object v) = Hit <$>
                         v .:  "_index"  <*>
                         v .:  "_type"   <*>
                         v .:  "_id"     <*>
                         v .:  "_score"  <*>
                         v .:  "_source" <*>
                         v .:? "highlight"
  parseJSON _          = empty

instance FromJSON ShardResult where
  parseJSON (Object v) = ShardResult       <$>
                         v .: "total"      <*>
                         v .: "successful" <*>
                         v .: "failed"
  parseJSON _          = empty


instance FromJSON DocVersion where
  parseJSON v = do
    i <- parseJSON v
    maybe (fail "DocVersion out of range") return $ mkDocVersion i

instance Bounded DocVersion where
  minBound = DocVersion 1
  maxBound = DocVersion 9200000000000000000 -- 9.2e+18

instance Enum DocVersion where
  succ x
    | x /= maxBound = DocVersion (succ $ docVersionNumber x)
    | otherwise     = succError "DocVersion"
  pred x
    | x /= minBound = DocVersion (pred $ docVersionNumber x)
    | otherwise     = predError "DocVersion"
  toEnum i =
    fromMaybe (error $ show i ++ " out of DocVersion range") $ mkDocVersion i
  fromEnum = docVersionNumber
  enumFrom = boundedEnumFrom
  enumFromThen = boundedEnumFromThen