From 972768eb265d2a95796d63400c10d9e8364076cb Mon Sep 17 00:00:00 2001
From: John McCardle <mccardle.john@gmail.com>
Date: Tue, 12 Mar 2024 21:02:48 -0400
Subject: [PATCH] inital PyCallable work; isolate very well behaved usage of
 PyObject references behind RAII

---
 src/GameEngine.cpp |  6 ++---
 src/GameEngine.h   |  4 +++-
 src/McRFPy_API.h   |  6 -----
 src/PyCallable.cpp | 57 ++++++++++++++++++++++++++++++++++++++++++++++
 src/PyCallable.h   | 26 +++++++++++++++++++++
 5 files changed, 89 insertions(+), 10 deletions(-)
 create mode 100644 src/PyCallable.cpp
 create mode 100644 src/PyCallable.h

diff --git a/src/GameEngine.cpp b/src/GameEngine.cpp
index 554eabf..beb2b31 100644
--- a/src/GameEngine.cpp
+++ b/src/GameEngine.cpp
@@ -75,7 +75,7 @@ void GameEngine::manageTimer(std::string name, PyObject* target, int interval)
     {
         if (target == NULL || target == Py_None) // delete
         {
-            Py_DECREF(timers[name].target);
+            //Py_DECREF(timers[name].target);
             timers.erase(it);
             return;
         }
@@ -85,7 +85,7 @@ void GameEngine::manageTimer(std::string name, PyObject* target, int interval)
         std::cout << "Refusing to initialize timer to None. It's not an error, it's just pointless." << std::endl;
         return;
     }
-    timers[name] = Timer(target, interval, runtime.getElapsedTime().asMilliseconds());
+    timers[name] = std::make_shared<PyTimerCallable>(target, interval, runtime.getElapsedTime().asMilliseconds());
     Py_INCREF(target);
 }
 
@@ -94,7 +94,7 @@ void GameEngine::testTimers()
     int now = runtime.getElapsedTime().asMilliseconds();
     for (auto& [name, timer]: timers)
     {
-        timer.test(now);
+        timer->test(now);
     }
 }
 
diff --git a/src/GameEngine.h b/src/GameEngine.h
index 138e74d..8d688b3 100644
--- a/src/GameEngine.h
+++ b/src/GameEngine.h
@@ -5,6 +5,7 @@
 #include "McRFPy_API.h"
 #include "IndexTexture.h"
 #include "Timer.h"
+#include "PyCallable.h"
 
 class GameEngine
 {
@@ -20,7 +21,8 @@ class GameEngine
     std::string window_title;
 
     sf::Clock runtime;
-    std::map<std::string, Timer> timers;
+    //std::map<std::string, Timer> timers;
+    std::map<std::string, std::shared_ptr<PyTimerCallable>> timers;
     void testTimers();
 
 public:
diff --git a/src/McRFPy_API.h b/src/McRFPy_API.h
index 588f897..025706b 100644
--- a/src/McRFPy_API.h
+++ b/src/McRFPy_API.h
@@ -12,12 +12,6 @@ private:
         texture_width = 12, texture_height = 11, // w & h sprite/frame count
         texture_sprite_count = 11 * 12; // t_width * t_height, minus blanks?
 
-    // TODO: this is wrong, load resources @ GameEngineSprite sprite;
-    // sf::Texture texture;
-
-    //std::vector<PyMethodDef> mcrfpyMethodsVector;
-    //static PyObject* PyInit_mcrfpy();
-
     McRFPy_API();
 
 public:
diff --git a/src/PyCallable.cpp b/src/PyCallable.cpp
new file mode 100644
index 0000000..5e16884
--- /dev/null
+++ b/src/PyCallable.cpp
@@ -0,0 +1,57 @@
+#include "PyCallable.h"
+
+PyCallable::PyCallable(PyObject* _target)
+{
+    target = Py_XNewRef(_target);
+}
+
+PyCallable::~PyCallable()
+{
+    if (target)
+        Py_DECREF(target);
+}
+
+PyObject* PyCallable::call(PyObject* args, PyObject* kwargs)
+{
+    return PyObject_Call(target, args, kwargs);
+}
+
+PyTimerCallable::PyTimerCallable(PyObject* _target, int _interval, int now)
+: PyCallable(_target), interval(_interval), last_ran(now)
+{}
+
+PyTimerCallable::PyTimerCallable()
+: PyCallable(Py_None), interval(0), last_ran(0)
+{}
+
+bool PyTimerCallable::hasElapsed(int now)
+{
+    return now >= last_ran + interval;
+}
+
+void PyTimerCallable::call(int now)
+{
+    PyObject* args = Py_BuildValue("(i)", now);
+    PyObject* retval = PyCallable::call(args, NULL);
+    if (!retval)
+    {
+        std::cout << "timer has raised an exception. It's going to STDERR and being dropped:" << std::endl;
+        PyErr_Print();
+        PyErr_Clear();
+    } else if (retval != Py_None)
+    {
+        std::cout << "timer returned a non-None value. It's not an error, it's just not being saved or used." << std::endl;
+        std::cout << PyUnicode_AsUTF8(PyObject_Repr(retval)) << std::endl;
+    }
+}
+
+bool PyTimerCallable::test(int now)
+{
+    if(hasElapsed(now))
+    {
+        call(now);
+        last_ran = now;
+        return true;
+    }
+    return false;
+}
diff --git a/src/PyCallable.h b/src/PyCallable.h
new file mode 100644
index 0000000..fd9257d
--- /dev/null
+++ b/src/PyCallable.h
@@ -0,0 +1,26 @@
+#pragma once
+#include "Common.h"
+#include "Python.h"
+
+class PyCallable
+{
+private:
+    PyObject* target;
+protected:
+    PyCallable(PyObject*);
+    ~PyCallable();
+    PyObject* call(PyObject*, PyObject*);
+};
+
+class PyTimerCallable: public PyCallable
+{
+private:
+    int interval;
+    int last_ran;
+    void call(int);
+public:
+    bool hasElapsed(int);
+    bool test(int);
+    PyTimerCallable(PyObject*, int, int);
+    PyTimerCallable();
+};