{-# LANGUAGE OverloadedStrings, RecordWildCards, FlexibleContexts #-}

module Database.Redis.ManualCommands where

import Prelude hiding (min, max)
import Data.ByteString (ByteString, empty, append)
import Data.Maybe (maybeToList)
import Database.Redis.Core
import Database.Redis.Protocol
import Database.Redis.Types


objectRefcount
    :: (RedisCtx m f)
    => ByteString -- ^ key
    -> m (f Integer)
objectRefcount key = sendRequest ["OBJECT", "refcount", encode key]

objectIdletime
    :: (RedisCtx m f)
    => ByteString -- ^ key
    -> m (f Integer)
objectIdletime key = sendRequest ["OBJECT", "idletime", encode key]

objectEncoding
    :: (RedisCtx m f)
    => ByteString -- ^ key
    -> m (f ByteString)
objectEncoding key = sendRequest ["OBJECT", "encoding", encode key]

linsertBefore
    :: (RedisCtx m f)
    => ByteString -- ^ key
    -> ByteString -- ^ pivot
    -> ByteString -- ^ value
    -> m (f Integer)
linsertBefore key pivot value =
    sendRequest ["LINSERT", encode key, "BEFORE", encode pivot, encode value]

linsertAfter
    :: (RedisCtx m f)
    => ByteString -- ^ key
    -> ByteString -- ^ pivot
    -> ByteString -- ^ value
    -> m (f Integer)
linsertAfter key pivot value =
        sendRequest ["LINSERT", encode key, "AFTER", encode pivot, encode value]

getType
    :: (RedisCtx m f)
    => ByteString -- ^ key
    -> m (f RedisType)
getType key = sendRequest ["TYPE", encode key]

-- |A single entry from the slowlog.
data Slowlog = Slowlog
    { slowlogId        :: Integer
      -- ^ A unique progressive identifier for every slow log entry.
    , slowlogTimestamp :: Integer
      -- ^ The unix timestamp at which the logged command was processed.
    , slowlogMicros    :: Integer
      -- ^ The amount of time needed for its execution, in microseconds.
    , slowlogCmd       :: [ByteString]
      -- ^ The command and it's arguments.
    } deriving (Show, Eq)

instance RedisResult Slowlog where
    decode (MultiBulk (Just [logId,timestamp,micros,cmd])) = do
        slowlogId        <- decode logId
        slowlogTimestamp <- decode timestamp
        slowlogMicros    <- decode micros
        slowlogCmd       <- decode cmd
        return Slowlog{..}
    decode r = Left r

slowlogGet
    :: (RedisCtx m f)
    => Integer -- ^ cnt
    -> m (f [Slowlog])
slowlogGet n = sendRequest ["SLOWLOG", "GET", encode n]

slowlogLen :: (RedisCtx m f) => m (f Integer)
slowlogLen = sendRequest ["SLOWLOG", "LEN"]

slowlogReset :: (RedisCtx m f) => m (f Status)
slowlogReset = sendRequest ["SLOWLOG", "RESET"]

zrange
    :: (RedisCtx m f)
    => ByteString -- ^ key
    -> Integer -- ^ start
    -> Integer -- ^ stop
    -> m (f [ByteString])
zrange key start stop =
    sendRequest ["ZRANGE", encode key, encode start, encode stop]

zrangeWithscores
    :: (RedisCtx m f)
    => ByteString -- ^ key
    -> Integer -- ^ start
    -> Integer -- ^ stop
    -> m (f [(ByteString, Double)])
zrangeWithscores key start stop =
    sendRequest ["ZRANGE", encode key, encode start, encode stop, "WITHSCORES"]

zrevrange
    :: (RedisCtx m f)
    => ByteString -- ^ key
    -> Integer -- ^ start
    -> Integer -- ^ stop
    -> m (f [ByteString])
zrevrange key start stop =
    sendRequest ["ZREVRANGE", encode key, encode start, encode stop]

zrevrangeWithscores
    :: (RedisCtx m f)
    => ByteString -- ^ key
    -> Integer -- ^ start
    -> Integer -- ^ stop
    -> m (f [(ByteString, Double)])
zrevrangeWithscores key start stop =
    sendRequest ["ZREVRANGE", encode key, encode start, encode stop
                ,"WITHSCORES"]

zrangebyscore
    :: (RedisCtx m f)
    => ByteString -- ^ key
    -> Double -- ^ min
    -> Double -- ^ max
    -> m (f [ByteString])
zrangebyscore key min max =
    sendRequest ["ZRANGEBYSCORE", encode key, encode min, encode max]

zrangebyscoreWithscores
    :: (RedisCtx m f)
    => ByteString -- ^ key
    -> Double -- ^ min
    -> Double -- ^ max
    -> m (f [(ByteString, Double)])
zrangebyscoreWithscores key min max =
    sendRequest ["ZRANGEBYSCORE", encode key, encode min, encode max
                ,"WITHSCORES"]

zrangebyscoreLimit
    :: (RedisCtx m f)
    => ByteString -- ^ key
    -> Double -- ^ min
    -> Double -- ^ max
    -> Integer -- ^ offset
    -> Integer -- ^ count
    -> m (f [ByteString])
zrangebyscoreLimit key min max offset count =
    sendRequest ["ZRANGEBYSCORE", encode key, encode min, encode max
                ,"LIMIT", encode offset, encode count]

zrangebyscoreWithscoresLimit
    :: (RedisCtx m f)
    => ByteString -- ^ key
    -> Double -- ^ min
    -> Double -- ^ max
    -> Integer -- ^ offset
    -> Integer -- ^ count
    -> m (f [(ByteString, Double)])
zrangebyscoreWithscoresLimit key min max offset count =
    sendRequest ["ZRANGEBYSCORE", encode key, encode min, encode max
                ,"WITHSCORES","LIMIT", encode offset, encode count]

zrevrangebyscore
    :: (RedisCtx m f)
    => ByteString -- ^ key
    -> Double -- ^ max
    -> Double -- ^ min
    -> m (f [ByteString])
zrevrangebyscore key min max =
    sendRequest ["ZREVRANGEBYSCORE", encode key, encode min, encode max]

zrevrangebyscoreWithscores
    :: (RedisCtx m f)
    => ByteString -- ^ key
    -> Double -- ^ max
    -> Double -- ^ min
    -> m (f [(ByteString, Double)])
zrevrangebyscoreWithscores key min max =
    sendRequest ["ZREVRANGEBYSCORE", encode key, encode min, encode max
                ,"WITHSCORES"]

zrevrangebyscoreLimit
    :: (RedisCtx m f)
    => ByteString -- ^ key
    -> Double -- ^ max
    -> Double -- ^ min
    -> Integer -- ^ offset
    -> Integer -- ^ count
    -> m (f [ByteString])
zrevrangebyscoreLimit key min max offset count =
    sendRequest ["ZREVRANGEBYSCORE", encode key, encode min, encode max
                ,"LIMIT", encode offset, encode count]

zrevrangebyscoreWithscoresLimit
    :: (RedisCtx m f)
    => ByteString -- ^ key
    -> Double -- ^ max
    -> Double -- ^ min
    -> Integer -- ^ offset
    -> Integer -- ^ count
    -> m (f [(ByteString, Double)])
zrevrangebyscoreWithscoresLimit key min max offset count =
    sendRequest ["ZREVRANGEBYSCORE", encode key, encode min, encode max
                ,"WITHSCORES","LIMIT", encode offset, encode count]

-- |Options for the 'sort' command.
data SortOpts = SortOpts
    { sortBy     :: Maybe ByteString
    , sortLimit  :: (Integer,Integer)
    , sortGet    :: [ByteString]
    , sortOrder  :: SortOrder
    , sortAlpha  :: Bool
    } deriving (Show, Eq)

-- |Redis default 'SortOpts'. Equivalent to omitting all optional parameters.
--
-- @
-- SortOpts
--     { sortBy    = Nothing -- omit the BY option
--     , sortLimit = (0,-1)  -- return entire collection
--     , sortGet   = []      -- omit the GET option
--     , sortOrder = Asc     -- sort in ascending order
--     , sortAlpha = False   -- sort numerically, not lexicographically
--     }
-- @
--
defaultSortOpts :: SortOpts
defaultSortOpts = SortOpts
    { sortBy    = Nothing
    , sortLimit = (0,-1)
    , sortGet   = []
    , sortOrder = Asc
    , sortAlpha = False
    }

data SortOrder = Asc | Desc deriving (Show, Eq)

sortStore
    :: (RedisCtx m f)
    => ByteString -- ^ key
    -> ByteString -- ^ destination
    -> SortOpts
    -> m (f Integer)
sortStore key dest = sortInternal key (Just dest)

sort
    :: (RedisCtx m f)
    => ByteString -- ^ key
    -> SortOpts
    -> m (f [ByteString])
sort key = sortInternal key Nothing

sortInternal
    :: (RedisResult a, RedisCtx m f)
    => ByteString -- ^ key
    -> Maybe ByteString -- ^ destination
    -> SortOpts
    -> m (f a)
sortInternal key destination SortOpts{..} = sendRequest $
    concat [["SORT", encode key], by, limit, get, order, alpha, store]
  where
    by    = maybe [] (\pattern -> ["BY", pattern]) sortBy
    limit = let (off,cnt) = sortLimit in ["LIMIT", encode off, encode cnt]
    get   = concatMap (\pattern -> ["GET", pattern]) sortGet
    order = case sortOrder of Desc -> ["DESC"]; Asc -> ["ASC"]
    alpha = ["ALPHA" | sortAlpha]
    store = maybe [] (\dest -> ["STORE", dest]) destination


data Aggregate = Sum | Min | Max deriving (Show,Eq)

zunionstore
    :: (RedisCtx m f)
    => ByteString -- ^ destination
    -> [ByteString] -- ^ keys
    -> Aggregate
    -> m (f Integer)
zunionstore dest keys =
    zstoreInternal "ZUNIONSTORE" dest keys []

zunionstoreWeights
    :: (RedisCtx m f)
    => ByteString -- ^ destination
    -> [(ByteString,Double)] -- ^ weighted keys
    -> Aggregate
    -> m (f Integer)
zunionstoreWeights dest kws =
    let (keys,weights) = unzip kws
    in zstoreInternal "ZUNIONSTORE" dest keys weights

zinterstore
    :: (RedisCtx m f)
    => ByteString -- ^ destination
    -> [ByteString] -- ^ keys
    -> Aggregate
    -> m (f Integer)
zinterstore dest keys =
    zstoreInternal "ZINTERSTORE" dest keys []

zinterstoreWeights
    :: (RedisCtx m f)
    => ByteString -- ^ destination
    -> [(ByteString,Double)] -- ^ weighted keys
    -> Aggregate
    -> m (f Integer)
zinterstoreWeights dest kws =
    let (keys,weights) = unzip kws
    in zstoreInternal "ZINTERSTORE" dest keys weights

zstoreInternal
    :: (RedisCtx m f)
    => ByteString -- ^ cmd
    -> ByteString -- ^ destination
    -> [ByteString] -- ^ keys
    -> [Double] -- ^ weights
    -> Aggregate
    -> m (f Integer)
zstoreInternal cmd dest keys weights aggregate = sendRequest $
    concat [ [cmd, dest, encode . toInteger $ length keys], keys
           , if null weights then [] else "WEIGHTS" : map encode weights
           , ["AGGREGATE", aggregate']
           ]
  where
    aggregate' = case aggregate of
        Sum -> "SUM"
        Min -> "MIN"
        Max -> "MAX"

eval
    :: (RedisCtx m f, RedisResult a)
    => ByteString -- ^ script
    -> [ByteString] -- ^ keys
    -> [ByteString] -- ^ args
    -> m (f a)
eval script keys args =
    sendRequest $ ["EVAL", script, encode numkeys] ++ keys ++ args
  where
    numkeys = toInteger (length keys)

evalsha
    :: (RedisCtx m f, RedisResult a)
    => ByteString -- ^ script
    -> [ByteString] -- ^ keys
    -> [ByteString] -- ^ args
    -> m (f a)
evalsha script keys args =
    sendRequest $ ["EVALSHA", script, encode numkeys] ++ keys ++ args
  where
    numkeys = toInteger (length keys)

bitcount
    :: (RedisCtx m f)
    => ByteString -- ^ key
    -> m (f Integer)
bitcount key = sendRequest ["BITCOUNT", key]

bitcountRange
    :: (RedisCtx m f)
    => ByteString -- ^ key
    -> Integer -- ^ start
    -> Integer -- ^ end
    -> m (f Integer)
bitcountRange key start end =
    sendRequest ["BITCOUNT", key, encode start, encode end]

bitopAnd
    :: (RedisCtx m f)
    => ByteString -- ^ destkey
    -> [ByteString] -- ^ srckeys
    -> m (f Integer)
bitopAnd dst srcs = bitop "AND" (dst:srcs)

bitopOr
    :: (RedisCtx m f)
    => ByteString -- ^ destkey
    -> [ByteString] -- ^ srckeys
    -> m (f Integer)
bitopOr dst srcs = bitop "OR" (dst:srcs)

bitopXor
    :: (RedisCtx m f)
    => ByteString -- ^ destkey
    -> [ByteString] -- ^ srckeys
    -> m (f Integer)
bitopXor dst srcs = bitop "XOR" (dst:srcs)

bitopNot
    :: (RedisCtx m f)
    => ByteString -- ^ destkey
    -> ByteString -- ^ srckey
    -> m (f Integer)
bitopNot dst src = bitop "NOT" [dst, src]

bitop
    :: (RedisCtx m f)
    => ByteString -- ^ operation
    -> [ByteString] -- ^ keys
    -> m (f Integer)
bitop op ks = sendRequest $ "BITOP" : op : ks

-- setRange
--   ::
-- setRange = sendRequest (["SET"] ++ [encode key] ++ [encode value] ++ )

migrate
    :: (RedisCtx m f)
    => ByteString -- ^ host
    -> ByteString -- ^ port
    -> ByteString -- ^ key
    -> Integer -- ^ destinationDb
    -> Integer -- ^ timeout
    -> m (f Status)
migrate host port key destinationDb timeout =
  sendRequest ["MIGRATE", host, port, key, encode destinationDb, encode timeout]


-- |Options for the 'migrate' command.
data MigrateOpts = MigrateOpts
    { migrateCopy    :: Bool
    , migrateReplace :: Bool
    } deriving (Show, Eq)

-- |Redis default 'MigrateOpts'. Equivalent to omitting all optional parameters.
--
-- @
-- MigrateOpts
--     { migrateCopy    = False -- remove the key from the local instance
--     , migrateReplace = False -- don't replace existing key on the remote instance
--     }
-- @
--
defaultMigrateOpts :: MigrateOpts
defaultMigrateOpts = MigrateOpts
    { migrateCopy    = False
    , migrateReplace = False
    }

migrateMultiple
    :: (RedisCtx m f)
    => ByteString   -- ^ host
    -> ByteString   -- ^ port
    -> Integer      -- ^ destinationDb
    -> Integer      -- ^ timeout
    -> MigrateOpts
    -> [ByteString] -- ^ keys
    -> m (f Status)
migrateMultiple host port destinationDb timeout MigrateOpts{..} keys =
    sendRequest $
    concat [["MIGRATE", host, port, empty, encode destinationDb, encode timeout],
            copy, replace, keys]
  where
    copy = ["COPY" | migrateCopy]
    replace = ["REPLACE" | migrateReplace]


restore
    :: (RedisCtx m f)
    => ByteString -- ^ key
    -> Integer -- ^ timeToLive
    -> ByteString -- ^ serializedValue
    -> m (f Status)
restore key timeToLive serializedValue =
  sendRequest ["RESTORE", key, encode timeToLive, serializedValue]


restoreReplace
    :: (RedisCtx m f)
    => ByteString -- ^ key
    -> Integer -- ^ timeToLive
    -> ByteString -- ^ serializedValue
    -> m (f Status)
restoreReplace key timeToLive serializedValue =
  sendRequest ["RESTORE", key, encode timeToLive, serializedValue, "REPLACE"]


set
    :: (RedisCtx m f)
    => ByteString -- ^ key
    -> ByteString -- ^ value
    -> m (f Status)
set key value = sendRequest ["SET", key, value]


data Condition = Nx | Xx deriving (Show, Eq)


instance RedisArg Condition where
  encode Nx = "NX"
  encode Xx = "XX"


data SetOpts = SetOpts
  { setSeconds      :: Maybe Integer
  , setMilliseconds :: Maybe Integer
  , setCondition    :: Maybe Condition
  } deriving (Show, Eq)


setOpts
    :: (RedisCtx m f)
    => ByteString -- ^ key
    -> ByteString -- ^ value
    -> SetOpts
    -> m (f Status)
setOpts key value SetOpts{..} =
    sendRequest $ concat [["SET", key, value], ex, px, condition]
  where
    ex = maybe [] (\s -> ["EX", encode s]) setSeconds
    px = maybe [] (\s -> ["PX", encode s]) setMilliseconds
    condition = map encode $ maybeToList setCondition


data DebugMode = Yes | Sync | No deriving (Show, Eq)


instance RedisArg DebugMode where
  encode Yes = "YES"
  encode Sync = "SYNC"
  encode No = "NO"


scriptDebug
    :: (RedisCtx m f)
    => DebugMode
    -> m (f Bool)
scriptDebug mode =
    sendRequest ["SCRIPT DEBUG", encode mode]


zadd
    :: (RedisCtx m f)
    => ByteString -- ^ key
    -> [(Double,ByteString)] -- ^ scoreMember
    -> m (f Integer)
zadd key scoreMembers =
  zaddOpts key scoreMembers defaultZaddOpts


data ZaddOpts = ZaddOpts
  { zaddCondition :: Maybe Condition
  , zaddChange    :: Bool
  , zaddIncrement :: Bool
  } deriving (Show, Eq)


-- |Redis default 'ZaddOpts'. Equivalent to omitting all optional parameters.
--
-- @
-- ZaddOpts
--     { zaddCondition = Nothing -- omit NX and XX options
--     , zaddChange    = False   -- don't modify the return value from the number of new elements added, to the total number of elements changed
--     , zaddIncrement = False   -- don't add like ZINCRBY
--     }
-- @
--
defaultZaddOpts :: ZaddOpts
defaultZaddOpts = ZaddOpts
  { zaddCondition = Nothing
  , zaddChange    = False
  , zaddIncrement = False
  }


zaddOpts
    :: (RedisCtx m f)
    => ByteString            -- ^ key
    -> [(Double,ByteString)] -- ^ scoreMember
    -> ZaddOpts              -- ^ options
    -> m (f Integer)
zaddOpts key scoreMembers ZaddOpts{..} =
    sendRequest $ concat [["ZADD", key], condition, change, increment, scores]
  where
    scores = concatMap (\(x,y) -> [encode x,encode y]) scoreMembers
    condition = map encode $ maybeToList zaddCondition
    change = ["CH" | zaddChange]
    increment = ["INCR" | zaddIncrement]


data ReplyMode = On | Off | Skip deriving (Show, Eq)


instance RedisArg ReplyMode where
  encode On = "ON"
  encode Off = "OFF"
  encode Skip = "SKIP"


clientReply
    :: (RedisCtx m f)
    => ReplyMode
    -> m (f Bool)
clientReply mode =
    sendRequest ["CLIENT REPLY", encode mode]


srandmember
    :: (RedisCtx m f)
    => ByteString -- ^ key
    -> m (f (Maybe ByteString))
srandmember key = sendRequest ["SRANDMEMBER", key]


srandmemberN
    :: (RedisCtx m f)
    => ByteString -- ^ key
    -> Integer -- ^ count
    -> m (f [ByteString])
srandmemberN key count = sendRequest ["SRANDMEMBER", key, encode count]


spop
    :: (RedisCtx m f)
    => ByteString -- ^ key
    -> m (f (Maybe ByteString))
spop key = sendRequest ["SPOP", key]


spopN
    :: (RedisCtx m f)
    => ByteString -- ^ key
    -> Integer -- ^ count
    -> m (f [ByteString])
spopN key count = sendRequest ["SPOP", key, encode count]


info
    :: (RedisCtx m f)
    => m (f ByteString)
info = sendRequest ["INFO"]


infoSection
    :: (RedisCtx m f)
    => ByteString -- ^ section
    -> m (f ByteString)
infoSection section = sendRequest ["INFO", section]


exists
    :: (RedisCtx m f)
    => ByteString -- ^ key
    -> m (f Bool)
exists key = sendRequest ["EXISTS", key]

newtype Cursor = Cursor ByteString deriving (Show, Eq)


instance RedisArg Cursor where
  encode (Cursor c) = encode c


instance RedisResult Cursor where
  decode (Bulk (Just s)) = Right $ Cursor s
  decode r               = Left r


cursor0 :: Cursor
cursor0 = Cursor "0"


scan
    :: (RedisCtx m f)
    => Cursor
    -> m (f (Cursor, [ByteString])) -- ^ next cursor and values
scan cursor = scanOpts cursor defaultScanOpts


data ScanOpts = ScanOpts
  { scanMatch :: Maybe ByteString
  , scanCount :: Maybe Integer
  } deriving (Show, Eq)


-- |Redis default 'ScanOpts'. Equivalent to omitting all optional parameters.
--
-- @
-- ScanOpts
--     { scanMatch = Nothing -- don't match any pattern
--     , scanCount = Nothing -- don't set any requirements on number elements returned (works like value @COUNT 10@)
--     }
-- @
--
defaultScanOpts :: ScanOpts
defaultScanOpts = ScanOpts
  { scanMatch = Nothing
  , scanCount = Nothing
  }


scanOpts
    :: (RedisCtx m f)
    => Cursor
    -> ScanOpts
    -> m (f (Cursor, [ByteString])) -- ^ next cursor and values
scanOpts cursor opts = sendRequest $ addScanOpts ["SCAN", encode cursor] opts


addScanOpts
    :: [ByteString] -- ^ main part of scan command
    -> ScanOpts
    -> [ByteString]
addScanOpts cmd ScanOpts{..} =
    concat [cmd, match, count]
  where
    prepend x y = [x, y]
    match       = maybe [] (prepend "MATCH") scanMatch
    count       = maybe [] ((prepend "COUNT").encode) scanCount

sscan
    :: (RedisCtx m f)
    => ByteString -- ^ key
    -> Cursor
    -> m (f (Cursor, [ByteString])) -- ^ next cursor and values
sscan key cursor = sscanOpts key cursor defaultScanOpts


sscanOpts
    :: (RedisCtx m f)
    => ByteString -- ^ key
    -> Cursor
    -> ScanOpts
    -> m (f (Cursor, [ByteString])) -- ^ next cursor and values
sscanOpts key cursor opts = sendRequest $ addScanOpts ["SSCAN", key, encode cursor] opts


hscan
    :: (RedisCtx m f)
    => ByteString -- ^ key
    -> Cursor
    -> m (f (Cursor, [(ByteString, ByteString)])) -- ^ next cursor and values
hscan key cursor = hscanOpts key cursor defaultScanOpts


hscanOpts
    :: (RedisCtx m f)
    => ByteString -- ^ key
    -> Cursor
    -> ScanOpts
    -> m (f (Cursor, [(ByteString, ByteString)])) -- ^ next cursor and values
hscanOpts key cursor opts = sendRequest $ addScanOpts ["HSCAN", key, encode cursor] opts


zscan
    :: (RedisCtx m f)
    => ByteString -- ^ key
    -> Cursor
    -> m (f (Cursor, [(ByteString, Double)])) -- ^ next cursor and values
zscan key cursor = zscanOpts key cursor defaultScanOpts


zscanOpts
    :: (RedisCtx m f)
    => ByteString -- ^ key
    -> Cursor
    -> ScanOpts
    -> m (f (Cursor, [(ByteString, Double)])) -- ^ next cursor and values
zscanOpts key cursor opts = sendRequest $ addScanOpts ["ZSCAN", key, encode cursor] opts

data RangeLex a = Incl a | Excl a | Minr | Maxr

instance RedisArg a => RedisArg (RangeLex a) where
  encode (Incl bs) = "[" `append` encode bs
  encode (Excl bs) = "(" `append` encode bs
  encode Minr      = "-"
  encode Maxr      = "+"

zrangebylex::(RedisCtx m f) =>
    ByteString             -- ^ key
    -> RangeLex ByteString -- ^ min
    -> RangeLex ByteString -- ^ max
    -> m (f [ByteString])
zrangebylex key min max =
    sendRequest ["ZRANGEBYLEX", encode key, encode min, encode max]

zrangebylexLimit
    ::(RedisCtx m f)
    => ByteString -- ^ key
    -> RangeLex ByteString -- ^ min
    -> RangeLex ByteString -- ^ max
    -> Integer             -- ^ offset
    -> Integer             -- ^ count
    -> m (f [ByteString])
zrangebylexLimit key min max offset count  =
    sendRequest ["ZRANGEBYLEX", encode key, encode min, encode max,
                 "LIMIT", encode offset, encode count]