/*
 * ***** BEGIN GPL LICENSE BLOCK *****
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 * ***** END GPL LICENSE BLOCK *****
 */

/** \file blender/python/intern/bpy_traceback.c
 *  \ingroup pythonintern
 *
 * This file contains utility functions for getting data from a python stack
 * trace.
 */


#include <Python.h>
#include <frameobject.h>

#include "BLI_utildefines.h"
#include "BLI_path_util.h"
#include "BLI_string.h"

#include "bpy_traceback.h"

static const char *traceback_filepath(PyTracebackObject *tb, PyObject **coerce)
{
	return PyBytes_AS_STRING((*coerce = PyUnicode_EncodeFSDefault(tb->tb_frame->f_code->co_filename)));
}

/* copied from pythonrun.c, 3.3.0 */
static int
parse_syntax_error(PyObject *err, PyObject **message, const char **filename,
                   int *lineno, int *offset, const char **text)
{
	long hold;
	PyObject *v;
	_Py_IDENTIFIER(msg);
	_Py_IDENTIFIER(filename);
	_Py_IDENTIFIER(lineno);
	_Py_IDENTIFIER(offset);
	_Py_IDENTIFIER(text);

	*message = NULL;

	/* new style errors.  `err' is an instance */
	*message = _PyObject_GetAttrId(err, &PyId_msg);
	if (!*message)
		goto finally;

	v = _PyObject_GetAttrId(err, &PyId_filename);
	if (!v)
		goto finally;
	if (v == Py_None) {
		Py_DECREF(v);
		*filename = NULL;
	}
	else {
		*filename = _PyUnicode_AsString(v);
		Py_DECREF(v);
		if (!*filename)
			goto finally;
	}

	v = _PyObject_GetAttrId(err, &PyId_lineno);
	if (!v)
		goto finally;
	hold = PyLong_AsLong(v);
	Py_DECREF(v);
	if (hold < 0 && PyErr_Occurred())
		goto finally;
	*lineno = (int)hold;

	v = _PyObject_GetAttrId(err, &PyId_offset);
	if (!v)
		goto finally;
	if (v == Py_None) {
		*offset = -1;
		Py_DECREF(v);
	} else {
		hold = PyLong_AsLong(v);
		Py_DECREF(v);
		if (hold < 0 && PyErr_Occurred())
			goto finally;
		*offset = (int)hold;
	}

	v = _PyObject_GetAttrId(err, &PyId_text);
	if (!v)
		goto finally;
	if (v == Py_None) {
		Py_DECREF(v);
		*text = NULL;
	}
	else {
		*text = _PyUnicode_AsString(v);
		Py_DECREF(v);
		if (!*text)
			goto finally;
	}
	return 1;

finally:
	Py_XDECREF(*message);
	return 0;
}
/* end copied function! */


void python_script_error_jump(const char *filepath, int *lineno, int *offset)
{
	PyObject *exception, *value;
	PyTracebackObject *tb;

	*lineno = -1;
	*offset = 0;

	PyErr_Fetch(&exception, &value, (PyObject **)&tb);

	if (exception && PyErr_GivenExceptionMatches(exception, PyExc_SyntaxError)) {
		/* no traceback available when SyntaxError.
		 * python has no api's to this. reference parse_syntax_error() from pythonrun.c */
		PyErr_NormalizeException(&exception, &value, (PyObject **)&tb);
		PyErr_Restore(exception, value, (PyObject *)tb);  /* takes away reference! */

		if (value) { /* should always be true */
			PyObject *message;
			const char *filename, *text;

			if (parse_syntax_error(value, &message, &filename, lineno, offset, &text)) {
				/* python adds a '/', prefix, so check for both */
				if ((BLI_path_cmp(filename, filepath) == 0) ||
				    ((filename[0] == '\\' || filename[0] == '/') && BLI_path_cmp(filename + 1, filepath) == 0))
				{
					/* good */
				}
				else {
					*lineno = -1;
				}
			}
			else {
				*lineno = -1;
			}
		}
	}
	else {
		PyErr_NormalizeException(&exception, &value, (PyObject **)&tb);
		PyErr_Restore(exception, value, (PyObject *)tb);  /* takes away reference! */
		PyErr_Print();

		for (tb = (PyTracebackObject *)PySys_GetObject("last_traceback");
		     tb && (PyObject *)tb != Py_None;
		     tb = tb->tb_next)
		{
			PyObject *coerce;
			const char *tb_filepath = traceback_filepath(tb, &coerce);
			const int match = ((BLI_path_cmp(tb_filepath, filepath) == 0) ||
			                   ((tb_filepath[0] == '\\' || tb_filepath[0] == '/') && BLI_path_cmp(tb_filepath + 1, filepath) == 0));
			Py_DECREF(coerce);

			if (match) {
				*lineno = tb->tb_lineno;
				/* used to break here, but better find the inner most line */
			}
		}
	}
}
