From 36a38f774a41d2050108874f2ff2321cabeb6942 Mon Sep 17 00:00:00 2001
From: Ollie Charles <ollie@ocharles.org.uk>
Date: Wed, 27 Jan 2021 09:12:38 +0000
Subject: [PATCH] Wrap GetCurrentContext and SetCurrentContext

---
 src/DearImGui.hs         | 20 +++++++++++++++++---
 src/DearImGui/Context.hs |  4 ++++
 2 files changed, 21 insertions(+), 3 deletions(-)

diff --git a/src/DearImGui.hs b/src/DearImGui.hs
index a796b22..9591853 100644
--- a/src/DearImGui.hs
+++ b/src/DearImGui.hs
@@ -18,6 +18,8 @@ module DearImGui
     Context(..)
   , createContext
   , destroyContext
+  , getCurrentContext
+  , setCurrentContext
 
     -- * Main
   , newFrame
@@ -139,19 +141,31 @@ Cpp.using "namespace ImGui"
 
 
 -- | Wraps @ImGuiContext*@.
-newtype Context = Context (Ptr ())
+newtype Context = Context (Ptr ImGuiContext)
 
 
 -- | Wraps @ImGui::CreateContext()@.
 createContext :: MonadIO m => m Context
 createContext = liftIO do
-  Context <$> [C.exp| void* { CreateContext() } |]
+  Context <$> [C.exp| ImGuiContext* { CreateContext() } |]
 
 
 -- | Wraps @ImGui::DestroyContext()@.
 destroyContext :: MonadIO m => Context -> m ()
 destroyContext (Context contextPtr) = liftIO do
-  [C.exp| void { DestroyContext((ImGuiContext*)$(void* contextPtr)); } |]
+  [C.exp| void { DestroyContext($(ImGuiContext* contextPtr)); } |]
+
+
+-- | Wraps @ImGui::GetCurrentContext()@.
+getCurrentContext :: MonadIO m => m Context
+getCurrentContext = liftIO do
+  Context <$> [C.exp| ImGuiContext* { GetCurrentContext() } |]
+
+
+-- | Wraps @ImGui::SetCurrentContext()@.
+setCurrentContext :: MonadIO m => Context -> m ()
+setCurrentContext (Context contextPtr) = liftIO do
+  [C.exp| void { SetCurrentContext($(ImGuiContext* contextPtr)) } |]
 
 
 -- | Start a new Dear ImGui frame, you can submit any command from this point
diff --git a/src/DearImGui/Context.hs b/src/DearImGui/Context.hs
index 3220ae3..37937a4 100644
--- a/src/DearImGui/Context.hs
+++ b/src/DearImGui/Context.hs
@@ -53,10 +53,14 @@ instance Storable ImVec4 where
     return ImVec4{ x, y, z, w }
 
 
+data ImGuiContext
+
+
 imguiContext :: Context
 imguiContext = mempty
   { ctxTypesTable = Map.fromList
       [ ( TypeName "ImVec3", [t| ImVec3 |] )
       , ( TypeName "ImVec4", [t| ImVec4 |] )
+      , ( TypeName "ImGuiContext", [t| ImGuiContext |])
       ]
   }