{- |
Copyright  : Will Thompson, Iñaki García Etxebarria and Jonas Platte
License    : LGPL-2.1
Maintainer : Iñaki García Etxebarria (inaki@blueleaf.cc)

An opaque structure used to iterate over attributes
in a 'GI.GIRepository.Structs.BaseInfo.BaseInfo' struct.
-}

#define ENABLE_OVERLOADING (MIN_VERSION_haskell_gi_overloading(1,0,0) \
       && !defined(__HADDOCK_VERSION__))

module GI.GIRepository.Structs.AttributeIter
    (

-- * Exported types
    AttributeIter(..)                       ,
    newZeroAttributeIter                    ,
    noAttributeIter                         ,


    ) where

import Data.GI.Base.ShortPrelude
import qualified Data.GI.Base.ShortPrelude as SP
import qualified Data.GI.Base.Overloading as O
import qualified Prelude as P

import qualified Data.GI.Base.Attributes as GI.Attributes
import qualified Data.GI.Base.ManagedPtr as B.ManagedPtr
import qualified Data.GI.Base.GClosure as B.GClosure
import qualified Data.GI.Base.GError as B.GError
import qualified Data.GI.Base.GVariant as B.GVariant
import qualified Data.GI.Base.GValue as B.GValue
import qualified Data.GI.Base.GParamSpec as B.GParamSpec
import qualified Data.GI.Base.CallStack as B.CallStack
import qualified Data.GI.Base.Properties as B.Properties
import qualified Data.Text as T
import qualified Data.ByteString.Char8 as B
import qualified Data.Map as Map
import qualified Foreign.Ptr as FP
import qualified GHC.OverloadedLabels as OL


-- | Memory-managed wrapper type.
newtype AttributeIter = AttributeIter (ManagedPtr AttributeIter)
instance WrappedPtr AttributeIter where
    wrappedPtrCalloc = callocBytes 32
    wrappedPtrCopy = \p -> withManagedPtr p (copyBytes 32 >=> wrapPtr AttributeIter)
    wrappedPtrFree = Just ptr_to_g_free

-- | Construct a `AttributeIter` struct initialized to zero.
newZeroAttributeIter :: MonadIO m => m AttributeIter
newZeroAttributeIter = liftIO $ wrappedPtrCalloc >>= wrapPtr AttributeIter

instance tag ~ 'AttrSet => Constructible AttributeIter tag where
    new _ attrs = do
        o <- newZeroAttributeIter
        GI.Attributes.set o attrs
        return o


-- | A convenience alias for `Nothing` :: `Maybe` `AttributeIter`.
noAttributeIter :: Maybe AttributeIter
noAttributeIter = Nothing


#if ENABLE_OVERLOADING
instance O.HasAttributeList AttributeIter
type instance O.AttributeList AttributeIter = AttributeIterAttributeList
type AttributeIterAttributeList = ('[ ] :: [(Symbol, *)])
#endif

#if ENABLE_OVERLOADING
type family ResolveAttributeIterMethod (t :: Symbol) (o :: *) :: * where
    ResolveAttributeIterMethod l o = O.MethodResolutionFailed l o

instance (info ~ ResolveAttributeIterMethod t AttributeIter, O.MethodInfo info AttributeIter p) => OL.IsLabel t (AttributeIter -> p) where
#if MIN_VERSION_base(4,10,0)
    fromLabel = O.overloadedMethod (O.MethodProxy :: O.MethodProxy info)
#else
    fromLabel _ = O.overloadedMethod (O.MethodProxy :: O.MethodProxy info)
#endif

#endif