// This is a rudimentary way to get some 'debug' information
// when a script goes awry.  I put this code in my ScriptManager
//  class.  I *called* it if the module_object returned from
// PyImport_ExecCodeModule returns NULL (for me this was on
// line 56 of ScriptManager.cpp).  I dumped the return value
// of this string to the log (using LL_SCRIPT log-level)

std::string ssurge::ScriptManager::getErrorString()
{
	PyObject * ptype, *pvalue;
	PyObject *ptrace;
	std::string s = "";

	PyErr_Fetch(&ptype, &pvalue, &ptrace);

	if (ptype != NULL)
	{
		PyObject * temps = PyObject_Str(ptype);
		char * tempcstr = PyUnicode_AsUTF8(temps);
		s += "ptype = " + std::string(tempcstr) + "\n";
		Py_DECREF(temps);
	}

	if (pvalue != NULL)
	{
		PyObject * temps = PyObject_Str(pvalue);
		char * tempcstr = PyUnicode_AsUTF8(temps);
		s += "pvalue = " + std::string(tempcstr) + "\n";
		Py_DECREF(temps);
	}

	if (ptrace != NULL)
	{
		s += "ptrace =\n";

		// The traceback object is more complex than the others: it's a linked-list
		// of "frames".  Each frame is a context (e.g. A called B, who called C would generate
		// a linked list of A -> B -> C).  Each frame has info about the filename, line#, etc.
		// Reference: http://stackoverflow.com/questions/1796510/accessing-a-python-traceback-from-the-c-api
		PyFrameObject * cur_frame;
		std::stringstream ss;
		PyTracebackObject * pactual_trace = (PyTracebackObject*)ptrace;
		
		while (pactual_trace != NULL)
		{
			cur_frame = pactual_trace->tb_frame;
			unsigned int frame_num = 0;
		
			char * fname = PyUnicode_AsUTF8(cur_frame->f_code->co_filename);
			int line = PyFrame_GetLineNumber(cur_frame);

			ss << "frame" << frame_num << ": " << fname << "@" << line << "\n";
			frame_num++;
			//cur_frame = cur_frame->f_back;
			pactual_trace = pactual_trace->tb_next;
		}
		s += ss.str() + "\n";
	}

	return s;
}