blender-archive/source/blender/python/intern/bpy_rna_callback.c

/*
 * 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.
 */

/** \file
 * \ingroup pythonintern
 *
 * This file currently exposes callbacks for interface regions but may be
 * extended later.
 */


#include <Python.h>

#include "RNA_types.h"

#include "BLI_utildefines.h"

#include "bpy_rna.h"
#include "bpy_rna_callback.h"
#include "bpy_capi_utils.h"

#include "DNA_space_types.h"
#include "DNA_screen_types.h"

#include "RNA_access.h"
#include "RNA_enum_types.h"

#include "BKE_context.h"
#include "BKE_screen.h"

#include "WM_api.h"

#include "ED_space_api.h"

#include "../generic/python_utildefines.h"

/* Use this to stop other capsules from being mis-used. */
static const char *rna_capsual_id = "RNA_HANDLE";
static const char *rna_capsual_id_invalid = "RNA_HANDLE_REMOVED";

static const EnumPropertyItem region_draw_mode_items[] = {
	{REGION_DRAW_POST_PIXEL, "POST_PIXEL", 0, "Post Pixel", ""},
	{REGION_DRAW_POST_VIEW, "POST_VIEW", 0, "Post View", ""},
	{REGION_DRAW_PRE_VIEW, "PRE_VIEW", 0, "Pre View", ""},
	{0, NULL, 0, NULL, NULL},
};

static void cb_region_draw(const bContext *C, ARegion *UNUSED(ar), void *customdata)
{
	PyObject *cb_func, *cb_args, *result;
	PyGILState_STATE gilstate;

	bpy_context_set((bContext *)C, &gilstate);

	cb_func = PyTuple_GET_ITEM((PyObject *)customdata, 1);
	cb_args = PyTuple_GET_ITEM((PyObject *)customdata, 2);
	result = PyObject_CallObject(cb_func, cb_args);

	if (result) {
		Py_DECREF(result);
	}
	else {
		PyErr_Print();
		PyErr_Clear();
	}

	bpy_context_clear((bContext *)C, &gilstate);
}

/* We could make generic utility */
static PyObject *PyC_Tuple_CopySized(PyObject *src, int len_dst)
{
	PyObject *dst = PyTuple_New(len_dst);
	int len_src = PyTuple_GET_SIZE(src);
	BLI_assert(len_src <= len_dst);
	for (int i = 0; i < len_src; i++) {
		PyObject *item = PyTuple_GET_ITEM(src, i);
		PyTuple_SET_ITEM(dst, i, item);
		Py_INCREF(item);
	}
	return dst;
}

static void cb_wm_cursor_draw(bContext *C, int x, int y, void *customdata)
{
	PyObject *cb_func, *cb_args, *result;
	PyGILState_STATE gilstate;

	bpy_context_set((bContext *)C, &gilstate);

	cb_func = PyTuple_GET_ITEM((PyObject *)customdata, 1);
	cb_args = PyTuple_GET_ITEM((PyObject *)customdata, 2);

	const int cb_args_len = PyTuple_GET_SIZE(cb_args);

	PyObject *cb_args_xy = PyTuple_New(2);
	PyTuple_SET_ITEMS(cb_args_xy, PyLong_FromLong(x), PyLong_FromLong(y));

	PyObject *cb_args_with_xy = PyC_Tuple_CopySized(cb_args, cb_args_len + 1);
	PyTuple_SET_ITEM(cb_args_with_xy, cb_args_len, cb_args_xy);

	result = PyObject_CallObject(cb_func, cb_args_with_xy);

	Py_DECREF(cb_args_with_xy);

	if (result) {
		Py_DECREF(result);
	}
	else {
		PyErr_Print();
		PyErr_Clear();
	}

	bpy_context_clear((bContext *)C, &gilstate);
}

#if 0
PyObject *pyrna_callback_add(BPy_StructRNA *self, PyObject *args)
{
	void *handle;

	PyObject *cb_func, *cb_args;
	char *cb_event_str = NULL;
	int cb_event;

	if (!PyArg_ParseTuple(args, "OO!|s:bpy_struct.callback_add", &cb_func, &PyTuple_Type, &cb_args, &cb_event_str)) {
		return NULL;
	}

	if (!PyCallable_Check(cb_func)) {
		PyErr_SetString(PyExc_TypeError, "callback_add(): first argument isn't callable");
		return NULL;
	}

	if (RNA_struct_is_a(self->ptr.type, &RNA_Region)) {
		if (cb_event_str) {
			if (pyrna_enum_value_from_id(
			            region_draw_mode_items, cb_event_str,
			            &cb_event, "bpy_struct.callback_add()") == -1)
			{
				return NULL;
			}
		}
		else {
			cb_event = REGION_DRAW_POST_PIXEL;
		}

		handle = ED_region_draw_cb_activate(((ARegion *)self->ptr.data)->type, cb_region_draw, (void *)args, cb_event);
		Py_INCREF(args);
	}
	else {
		PyErr_SetString(PyExc_TypeError, "callback_add(): type does not support callbacks");
		return NULL;
	}

	return PyCapsule_New((void *)handle, rna_capsual_id, NULL);
}

PyObject *pyrna_callback_remove(BPy_StructRNA *self, PyObject *args)
{
	PyObject *py_handle;
	void *handle;
	void *customdata;

	if (!PyArg_ParseTuple(args, "O!:callback_remove", &PyCapsule_Type, &py_handle)) {
		return NULL;
	}

	handle = PyCapsule_GetPointer(py_handle, rna_capsual_id);

	if (handle == NULL) {
		PyErr_SetString(PyExc_ValueError, "callback_remove(handle): NULL handle given, invalid or already removed");
		return NULL;
	}

	if (RNA_struct_is_a(self->ptr.type, &RNA_Region)) {
		customdata = ED_region_draw_cb_customdata(handle);
		Py_DECREF((PyObject *)customdata);

		ED_region_draw_cb_exit(((ARegion *)self->ptr.data)->type, handle);
	}
	else {
		PyErr_SetString(PyExc_TypeError, "callback_remove(): type does not support callbacks");
		return NULL;
	}

	/* don't allow reuse */
	PyCapsule_SetName(py_handle, rna_capsual_id_invalid);

	Py_RETURN_NONE;
}
#endif

/* reverse of rna_Space_refine() */
static eSpace_Type rna_Space_refine_reverse(StructRNA *srna)
{
	if (srna == &RNA_SpaceView3D)           { return SPACE_VIEW3D; }
	if (srna == &RNA_SpaceGraphEditor)      { return SPACE_GRAPH; }
	if (srna == &RNA_SpaceOutliner)         { return SPACE_OUTLINER; }
	if (srna == &RNA_SpaceProperties)       { return SPACE_PROPERTIES; }
	if (srna == &RNA_SpaceFileBrowser)      { return SPACE_FILE; }
	if (srna == &RNA_SpaceImageEditor)      { return SPACE_IMAGE; }
	if (srna == &RNA_SpaceInfo)             { return SPACE_INFO; }
	if (srna == &RNA_SpaceSequenceEditor)   { return SPACE_SEQ; }
	if (srna == &RNA_SpaceTextEditor)       { return SPACE_TEXT; }
	if (srna == &RNA_SpaceDopeSheetEditor)  { return SPACE_ACTION; }
	if (srna == &RNA_SpaceNLA)              { return SPACE_NLA; }
	if (srna == &RNA_SpaceNodeEditor)       { return SPACE_NODE; }
	if (srna == &RNA_SpaceConsole)          { return SPACE_CONSOLE; }
	if (srna == &RNA_SpacePreferences)      { return SPACE_USERPREF; }
	if (srna == &RNA_SpaceClipEditor)       { return SPACE_CLIP; }
	return SPACE_EMPTY;
}

PyObject *pyrna_callback_classmethod_add(PyObject *UNUSED(self), PyObject *args)
{
	void *handle;
	PyObject *cls;
	PyObject *cb_func, *cb_args;
	StructRNA *srna;

	if (PyTuple_GET_SIZE(args) < 2) {
		PyErr_SetString(PyExc_ValueError, "handler_add(handler): expected at least 2 args");
		return NULL;
	}

	cls = PyTuple_GET_ITEM(args, 0);
	if (!(srna = pyrna_struct_as_srna(cls, false, "handler_add"))) {
		return NULL;
	}
	cb_func = PyTuple_GET_ITEM(args, 1);
	if (!PyCallable_Check(cb_func)) {
		PyErr_SetString(PyExc_TypeError, "first argument isn't callable");
		return NULL;
	}

	/* class specific callbacks */

	if (srna == &RNA_WindowManager) {
		const char *error_prefix = "WindowManager.draw_cursor_add";
		struct {
			const char *space_type_str;
			const char *region_type_str;

			int space_type;
			int region_type;
		} params = {
			.space_type_str = NULL,
			.region_type_str = NULL,
			.space_type = SPACE_TYPE_ANY,
			.region_type = RGN_TYPE_ANY,
		};

		if (!PyArg_ParseTuple(
		            args, "OOO!|ss:WindowManager.draw_cursor_add",
		            &cls, &cb_func,  /* already assigned, no matter */
		            &PyTuple_Type, &cb_args, &params.space_type_str, &params.region_type_str))
		{
			return NULL;
		}

		if (params.space_type_str && pyrna_enum_value_from_id(
		            rna_enum_space_type_items, params.space_type_str,
		            &params.space_type, error_prefix) == -1)
		{
			return NULL;
		}
		else if (params.region_type_str && pyrna_enum_value_from_id(
		            rna_enum_region_type_items, params.region_type_str,
		            &params.region_type, error_prefix) == -1)
		{
			return NULL;
		}

		bContext *C = BPy_GetContext();
		struct wmWindowManager *wm = CTX_wm_manager(C);
		handle = WM_paint_cursor_activate(
		        wm,
		        params.space_type, params.region_type,
		        NULL, cb_wm_cursor_draw, (void *)args);
	}
	else if (RNA_struct_is_a(srna, &RNA_Space)) {
		const char *error_prefix = "Space.draw_handler_add";
		struct {
			const char *region_type_str;
			const char *event_str;

			int region_type;
			int event;
		} params;

		if (!PyArg_ParseTuple(
		            args, "OOO!ss:Space.draw_handler_add",
		            &cls, &cb_func,  /* already assigned, no matter */
		            &PyTuple_Type, &cb_args,
		            &params.region_type_str, &params.event_str))
		{
			return NULL;
		}

		if (pyrna_enum_value_from_id(
		            region_draw_mode_items, params.event_str,
		            &params.event, error_prefix) == -1)
		{
			return NULL;
		}
		else if (pyrna_enum_value_from_id(
		                 rna_enum_region_type_items, params.region_type_str,
		                 &params.region_type, error_prefix) == -1)
		{
			return NULL;
		}
		else {
			const eSpace_Type spaceid = rna_Space_refine_reverse(srna);
			if (spaceid == SPACE_EMPTY) {
				PyErr_Format(PyExc_TypeError, "unknown space type '%.200s'", RNA_struct_identifier(srna));
				return NULL;
			}
			else {
				SpaceType *st = BKE_spacetype_from_id(spaceid);
				ARegionType *art = BKE_regiontype_from_id(st, params.region_type);
				if (art == NULL) {
					PyErr_Format(PyExc_TypeError, "region type '%.200s' not in space", params.region_type_str);
					return NULL;
				}
				handle = ED_region_draw_cb_activate(art, cb_region_draw, (void *)args, params.event);
			}
		}
	}
	else {
		PyErr_SetString(PyExc_TypeError, "callback_add(): type does not support callbacks");
		return NULL;
	}

	PyObject *ret = PyCapsule_New((void *)handle, rna_capsual_id, NULL);

	/* Store 'args' in context as well as the handler custom-data,
	 * because the handle may be freed by Blender (new file, new window... etc) */
	PyCapsule_SetContext(ret, args);
	Py_INCREF(args);

	return ret;
}

PyObject *pyrna_callback_classmethod_remove(PyObject *UNUSED(self), PyObject *args)
{
	PyObject *cls;
	PyObject *py_handle;
	void *handle;
	StructRNA *srna;
	bool capsule_clear = false;

	if (PyTuple_GET_SIZE(args) < 2) {
		PyErr_SetString(PyExc_ValueError, "callback_remove(handler): expected at least 2 args");
		return NULL;
	}

	cls = PyTuple_GET_ITEM(args, 0);
	if (!(srna = pyrna_struct_as_srna(cls, false, "callback_remove"))) {
		return NULL;
	}
	py_handle = PyTuple_GET_ITEM(args, 1);
	handle = PyCapsule_GetPointer(py_handle, rna_capsual_id);
	if (handle == NULL) {
		PyErr_SetString(PyExc_ValueError, "callback_remove(handler): NULL handler given, invalid or already removed");
		return NULL;
	}
	PyObject *handle_args = PyCapsule_GetContext(py_handle);

	if (srna == &RNA_WindowManager) {
		if (!PyArg_ParseTuple(
		            args, "OO!:WindowManager.draw_cursor_remove",
		            &cls, &PyCapsule_Type, &py_handle))
		{
			return NULL;
		}
		bContext *C = BPy_GetContext();
		struct wmWindowManager *wm = CTX_wm_manager(C);
		WM_paint_cursor_end(wm, handle);
		capsule_clear = true;
	}
	else if (RNA_struct_is_a(srna, &RNA_Space)) {
		const char *error_prefix = "Space.draw_handler_remove";
		struct {
			const char *region_type_str;

			int region_type;
		} params;

		if (!PyArg_ParseTuple(
		            args, "OO!s:Space.draw_handler_remove",
		            &cls, &PyCapsule_Type, &py_handle,  /* already assigned, no matter */
		            &params.region_type_str))
		{
			return NULL;
		}

		if (pyrna_enum_value_from_id(
		            rna_enum_region_type_items, params.region_type_str,
		            &params.region_type, error_prefix) == -1)
		{
			return NULL;
		}
		else {
			const eSpace_Type spaceid = rna_Space_refine_reverse(srna);
			if (spaceid == SPACE_EMPTY) {
				PyErr_Format(PyExc_TypeError, "unknown space type '%.200s'", RNA_struct_identifier(srna));
				return NULL;
			}
			else {
				SpaceType *st = BKE_spacetype_from_id(spaceid);
				ARegionType *art = BKE_regiontype_from_id(st, params.region_type);
				if (art == NULL) {
					PyErr_Format(PyExc_TypeError, "region type '%.200s' not in space", params.region_type_str);
					return NULL;
				}
				ED_region_draw_cb_exit(art, handle);
				capsule_clear = true;
			}
		}
	}
	else {
		PyErr_SetString(PyExc_TypeError, "callback_remove(): type does not support callbacks");
		return NULL;
	}

	/* don't allow reuse */
	if (capsule_clear) {
		Py_DECREF(handle_args);
		PyCapsule_SetName(py_handle, rna_capsual_id_invalid);
	}

	Py_RETURN_NONE;
}