Add script engine and connect to std console

src/openrct2/Context.cpp

@@ -57,6 +57,7 @@
 #include "ride/TrackDesignRepository.h"
 #include "scenario/Scenario.h"
 #include "scenario/ScenarioRepository.h"
+#include "scripting/ScriptEngine.h"
 #include "title/TitleScreen.h"
 #include "title/TitleSequenceManager.h"
 #include "ui/UiContext.h"
@@ -76,6 +77,7 @@ using namespace OpenRCT2::Audio;
 using namespace OpenRCT2::Drawing;
 using namespace OpenRCT2::Localisation;
 using namespace OpenRCT2::Paint;
+using namespace OpenRCT2::Scripting;
 using namespace OpenRCT2::Ui;
 
 namespace OpenRCT2
@@ -100,6 +102,7 @@ namespace OpenRCT2
         std::unique_ptr<DiscordService> _discordService;
 #endif
         StdInOutConsole _stdInOutConsole;
+        ScriptEngine _scriptEngine;
 
         // Game states
         std::unique_ptr<TitleScreen> _titleScreen;
@@ -135,6 +138,7 @@ namespace OpenRCT2
             , _uiContext(uiContext)
             , _localisationService(std::make_unique<LocalisationService>(env))
             , _painter(std::make_unique<Painter>(uiContext))
+            , _scriptEngine(_stdInOutConsole, *env)
         {
             // Can't have more than one context currently.
             Guard::Assert(Instance == nullptr);
@@ -176,6 +180,11 @@ namespace OpenRCT2
             return _uiContext;
         }
 
+        Scripting::ScriptEngine& GetScriptEngine() override
+        {
+            return _scriptEngine;
+        }
+
         GameState* GetGameState() override
         {
             return _gameState.get();
@@ -1015,7 +1024,7 @@ namespace OpenRCT2
 
             Twitch::Update();
             chat_update();
-            _stdInOutConsole.ProcessEvalQueue();
+            _scriptEngine.Update();
             _uiContext->Update();
         }
 

src/openrct2/Context.h

@@ -85,6 +85,11 @@ namespace OpenRCT2
         class LocalisationService;
     }
 
+    namespace Scripting
+    {
+        class ScriptEngine;
+    }
+
     namespace Ui
     {
         interface IUiContext;
@@ -109,6 +114,7 @@ namespace OpenRCT2
         virtual Localisation::LocalisationService& GetLocalisationService() abstract;
         virtual IObjectManager& GetObjectManager() abstract;
         virtual IObjectRepository& GetObjectRepository() abstract;
+        virtual Scripting::ScriptEngine& GetScriptEngine() abstract;
         virtual ITrackDesignRepository* GetTrackDesignRepository() abstract;
         virtual IScenarioRepository* GetScenarioRepository() abstract;
         virtual IReplayManager* GetReplayManager() abstract;

src/openrct2/interface/InteractiveConsole.h

@@ -12,11 +12,8 @@
 #include "../common.h"
 #include "../localisation/FormatCodes.h"
 
-#include <deque>
 #include <future>
-#include <queue>
 #include <string>
-#include <tuple>
 
 struct rct_drawpixelinfo;
 struct TextInputSession;
@@ -53,13 +50,9 @@ public:
 
 class StdInOutConsole final : public InteractiveConsole
 {
-private:
-    std::queue<std::tuple<std::promise<void>, std::string>> _evalQueue;
-
 public:
     void Start();
     std::future<void> Eval(const std::string& s);
-    void ProcessEvalQueue();
 
     void Clear() override;
     void Close() override;

src/openrct2/interface/StdInOutConsole.cpp

@@ -7,11 +7,15 @@
  * OpenRCT2 is licensed under the GNU General Public License version 3.
  *****************************************************************************/
 
+#include "../Context.h"
 #include "../OpenRCT2.h"
 #include "../platform/Platform2.h"
+#include "../scripting/ScriptEngine.h"
 #include "../thirdparty/linenoise.hpp"
 #include "InteractiveConsole.h"
 
+using namespace OpenRCT2;
+
 void StdInOutConsole::Start()
 {
     std::thread replThread([this]() -> void {
@@ -51,28 +55,8 @@ void StdInOutConsole::Start()
 
 std::future<void> StdInOutConsole::Eval(const std::string& s)
 {
-    // Push on-demand evaluations onto a queue so that it can be processed deterministically
-    // on the main thead at the right time.
-    std::promise<void> barrier;
-    auto future = barrier.get_future();
-    _evalQueue.emplace(std::move(barrier), s);
-    return future;
-}
-
-void StdInOutConsole::ProcessEvalQueue()
-{
-    while (_evalQueue.size() > 0)
-    {
-        auto item = std::move(_evalQueue.front());
-        _evalQueue.pop();
-        auto promise = std::move(std::get<0>(item));
-        auto command = std::move(std::get<1>(item));
-
-        Execute(command);
-
-        // Signal the promise so caller can continue
-        promise.set_value();
-    }
+    auto& scriptEngine = GetContext()->GetScriptEngine();
+    return scriptEngine.Eval(s);
 }
 
 void StdInOutConsole::Clear()

src/openrct2/scripting/ScriptEngine.cpp

@@ -0,0 +1,79 @@
+/*****************************************************************************
+ * Copyright (c) 2014-2018 OpenRCT2 developers
+ *
+ * For a complete list of all authors, please refer to contributors.md
+ * Interested in contributing? Visit https://github.com/OpenRCT2/OpenRCT2
+ *
+ * OpenRCT2 is licensed under the GNU General Public License version 3.
+ *****************************************************************************/
+
+#include "ScriptEngine.h"
+#include "../interface/InteractiveConsole.h"
+#include <duktape.h>
+#include <stdexcept>
+
+using namespace OpenRCT2;
+using namespace OpenRCT2::Scripting;
+
+static std::string Stringify(duk_context * ctx, duk_idx_t idx);
+
+ScriptEngine::ScriptEngine(InteractiveConsole& console, IPlatformEnvironment& env) :
+    _console(console),
+    _env(env)
+{
+    _context = duk_create_heap_default();
+    if (_context == nullptr)
+    {
+        throw std::runtime_error("Unable to initialise duktape context.");
+    }
+}
+
+ScriptEngine::~ScriptEngine()
+{
+    duk_destroy_heap(_context);
+}
+
+void ScriptEngine::Update()
+{
+    while (_evalQueue.size() > 0)
+    {
+        auto item = std::move(_evalQueue.front());
+        _evalQueue.pop();
+        auto promise = std::move(std::get<0>(item));
+        auto command = std::move(std::get<1>(item));
+        if (duk_peval_string(_context, command.c_str()) != 0)
+        {
+            std::string result = std::string(duk_safe_to_string(_context, -1));
+            _console.WriteLineError(result);
+        }
+        else
+        {
+            std::string result = Stringify(_context, -1);
+            _console.WriteLine(result);
+        }
+        duk_pop(_context);
+        // Signal the promise so caller can continue
+        promise.set_value();
+    }
+}
+
+std::future<void> ScriptEngine::Eval(const std::string &s)
+{
+    std::promise<void> barrier;
+    auto future = barrier.get_future();
+    _evalQueue.emplace(std::move(barrier), s);
+    return future;
+}
+
+static std::string Stringify(duk_context * ctx, duk_idx_t idx)
+{
+    auto type = duk_get_type(ctx, idx);
+    if (type == DUK_TYPE_OBJECT && !duk_is_function(ctx, idx))
+    {
+        return duk_json_encode(ctx, idx);
+    }
+    else
+    {
+        return duk_safe_to_string(ctx, idx);
+    }
+}

src/openrct2/scripting/ScriptEngine.h

@@ -0,0 +1,45 @@
+/*****************************************************************************
+ * Copyright (c) 2014-2018 OpenRCT2 developers
+ *
+ * For a complete list of all authors, please refer to contributors.md
+ * Interested in contributing? Visit https://github.com/OpenRCT2/OpenRCT2
+ *
+ * OpenRCT2 is licensed under the GNU General Public License version 3.
+ *****************************************************************************/
+
+#pragma once
+
+#include "../common.h"
+#include <future>
+#include <queue>
+#include <string>
+
+struct duk_hthread;
+typedef struct duk_hthread duk_context;
+
+class InteractiveConsole;
+
+namespace OpenRCT2
+{
+    interface IPlatformEnvironment;
+}
+
+namespace OpenRCT2::Scripting
+{
+    class ScriptEngine
+    {
+    private:
+        InteractiveConsole& _console;
+        IPlatformEnvironment& _env;
+        duk_context * _context;
+        std::queue<std::tuple<std::promise<void>, std::string>> _evalQueue;
+
+    public:
+        ScriptEngine(InteractiveConsole& console, IPlatformEnvironment& env);
+        ScriptEngine(ScriptEngine&&) = delete;
+        ~ScriptEngine();
+
+        void Update();
+        std::future<void> Eval(const std::string &s);
+    };
+}