bpy_library.c

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/*
 * ***** 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.
 *
 * Contributor(s): Campbell Barton
 *
 * ***** END GPL LICENSE BLOCK *****
 */

/* nifty feature. swap out strings for RNA data */
#define USE_RNA_DATABLOCKS

#include <Python.h>
#include <stddef.h>

#include "BLO_readfile.h"

#include "BKE_global.h"
#include "BKE_main.h"
#include "BKE_library.h"
#include "BKE_idcode.h"
#include "BKE_report.h"
#include "BKE_context.h"

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

#include "DNA_space_types.h" /* FILE_LINK, FILE_RELPATH */

#include "bpy_util.h"

#ifdef USE_RNA_DATABLOCKS
#  include "bpy_rna.h"
#  include "RNA_access.h"
#endif

typedef struct {
    PyObject_HEAD /* required python macro   */
    /* collection iterator specific parts */
    char relpath[FILE_MAX];
    char abspath[FILE_MAX]; /* absolute path */
    BlendHandle *blo_handle;
    int flag;
    PyObject *dict;
} BPy_Library;

static PyObject *bpy_lib_load(PyObject *self, PyObject *args, PyObject *kwds);
static PyObject *bpy_lib_enter(BPy_Library *self, PyObject *args);
static PyObject *bpy_lib_exit(BPy_Library *self, PyObject *args);
static PyObject *bpy_lib_dir(BPy_Library *self);

static PyMethodDef bpy_lib_methods[] = {
    {"__enter__", (PyCFunction)bpy_lib_enter, METH_NOARGS},
    {"__exit__",  (PyCFunction)bpy_lib_exit,  METH_VARARGS},
    {"__dir__",   (PyCFunction)bpy_lib_dir,   METH_NOARGS},
    {NULL}           /* sentinel */
};

static void bpy_lib_dealloc(BPy_Library *self)
{
    Py_XDECREF(self->dict);
    Py_TYPE(self)->tp_free(self);
}


static PyTypeObject bpy_lib_Type = {
    PyVarObject_HEAD_INIT(NULL, 0)
    "bpy_lib",      /* tp_name */
    sizeof(BPy_Library),            /* tp_basicsize */
    0,                          /* tp_itemsize */
    /* methods */
    (destructor)bpy_lib_dealloc,/* tp_dealloc */
    NULL,                       /* printfunc tp_print; */
    NULL,                       /* getattrfunc tp_getattr; */
    NULL,                       /* setattrfunc tp_setattr; */
    NULL,                       /* tp_compare */ /* DEPRECATED in python 3.0! */
    NULL,                       /* tp_repr */

    /* Method suites for standard classes */

    NULL,                       /* PyNumberMethods *tp_as_number; */
    NULL,                       /* PySequenceMethods *tp_as_sequence; */
    NULL,                       /* PyMappingMethods *tp_as_mapping; */

    /* More standard operations (here for binary compatibility) */

    NULL,                       /* hashfunc tp_hash; */
    NULL,                       /* ternaryfunc tp_call; */
    NULL,                       /* reprfunc tp_str; */

    /* will only use these if this is a subtype of a py class */
    NULL /*PyObject_GenericGetAttr is assigned later */,    /* getattrofunc tp_getattro; */
    NULL,                       /* setattrofunc tp_setattro; */

    /* Functions to access object as input/output buffer */
    NULL,                       /* PyBufferProcs *tp_as_buffer; */

  /*** Flags to define presence of optional/expanded features ***/
    Py_TPFLAGS_DEFAULT,         /* long tp_flags; */

    NULL,                       /*  char *tp_doc;  Documentation string */
  /*** Assigned meaning in release 2.0 ***/
    /* call function for all accessible objects */
    NULL,                       /* traverseproc tp_traverse; */

    /* delete references to contained objects */
    NULL,                       /* inquiry tp_clear; */

  /***  Assigned meaning in release 2.1 ***/
  /*** rich comparisons ***/
    NULL, /* subclassed */      /* richcmpfunc tp_richcompare; */

  /***  weak reference enabler ***/
    0,
  /*** Added in release 2.2 ***/
    /*   Iterators */
    NULL,                       /* getiterfunc tp_iter; */
    NULL,                       /* iternextfunc tp_iternext; */

  /*** Attribute descriptor and subclassing stuff ***/
    bpy_lib_methods,            /* struct PyMethodDef *tp_methods; */
    NULL,                       /* struct PyMemberDef *tp_members; */
    NULL,                       /* struct PyGetSetDef *tp_getset; */
    NULL,                       /* struct _typeobject *tp_base; */
    NULL,                       /* PyObject *tp_dict; */
    NULL,                       /* descrgetfunc tp_descr_get; */
    NULL,                       /* descrsetfunc tp_descr_set; */
    offsetof(BPy_Library, dict),/* long tp_dictoffset; */
    NULL,                       /* initproc tp_init; */
    NULL,                       /* allocfunc tp_alloc; */
    NULL,                       /* newfunc tp_new; */
    /*  Low-level free-memory routine */
    NULL,                       /* freefunc tp_free;  */
    /* For PyObject_IS_GC */
    NULL,                       /* inquiry tp_is_gc;  */
    NULL,                       /* PyObject *tp_bases; */
    /* method resolution order */
    NULL,                       /* PyObject *tp_mro;  */
    NULL,                       /* PyObject *tp_cache; */
    NULL,                       /* PyObject *tp_subclasses; */
    NULL,                       /* PyObject *tp_weaklist; */
    NULL
};

PyDoc_STRVAR(bpy_lib_load_doc,
".. method:: load(filepath, link=False, relative=False)\n"
"\n"
"   Returns a context manager which exposes 2 library objects on entering.\n"
"   Each object has attributes matching bpy.data which are lists of strings to be linked.\n"
"\n"
"   :arg filepath: The path to a blend file.\n"
"   :type filepath: string\n"
"   :arg link: When False reference to the original file is lost.\n"
"   :type link: bool\n"
"   :arg relative: When True the path is stored relative to the open blend file.\n"
"   :type relative: bool\n"
);
static PyObject *bpy_lib_load(PyObject *UNUSED(self), PyObject *args, PyObject *kwds)
{
    static const char *kwlist[] = {"filepath", "link", "relative", NULL};
    BPy_Library *ret;
    const char* filename = NULL;
    int is_rel = 0, is_link = 0;

    if (!PyArg_ParseTupleAndKeywords(args, kwds, "s|ii:load", (char **)kwlist, &filename, &is_link, &is_rel))
        return NULL;

    ret = PyObject_New(BPy_Library, &bpy_lib_Type);

    BLI_strncpy(ret->relpath, filename, sizeof(ret->relpath));
    BLI_strncpy(ret->abspath, filename, sizeof(ret->abspath));
    BLI_path_abs(ret->abspath, G.main->name);

    ret->blo_handle = NULL;
    ret->flag=  (is_link ? FILE_LINK : 0) |
                (is_rel ? FILE_RELPATH : 0);

    ret->dict = PyDict_New();

    return (PyObject *)ret;
}

static PyObject *_bpy_names(BPy_Library *self, int blocktype)
{
    PyObject *list;
    LinkNode *l, *names;
    int totnames;

    names = BLO_blendhandle_get_datablock_names(self->blo_handle, blocktype, &totnames);

    if (names) {
        int counter = 0;
        list = PyList_New(totnames);
        for (l = names; l; l = l->next) {
            PyList_SET_ITEM(list, counter, PyUnicode_FromString((char *)l->link));
            counter++;
        }
        BLI_linklist_free(names, free); /* free linklist *and* each node's data */
    }
    else {
        list = PyList_New(0);
    }

    return list;
}

static PyObject *bpy_lib_enter(BPy_Library *self, PyObject *UNUSED(args))
{
    PyObject *ret;
    BPy_Library *self_from;
    PyObject *from_dict = PyDict_New();
    ReportList reports;

    BKE_reports_init(&reports, RPT_STORE);

    self->blo_handle = BLO_blendhandle_from_file(self->abspath, &reports);

    if (self->blo_handle == NULL) {
        if (BPy_reports_to_error(&reports, PyExc_IOError, TRUE) != -1) {
            PyErr_Format(PyExc_IOError,
                         "load: %s failed to open blend file",
                         self->abspath);
        }
        return NULL;
    }
    else {
        int i = 0, code;
        while ((code = BKE_idcode_iter_step(&i))) {
            if (BKE_idcode_is_linkable(code)) {
                const char *name_plural = BKE_idcode_to_name_plural(code);
                PyObject *str = PyUnicode_FromString(name_plural);
                PyDict_SetItem(self->dict, str, PyList_New(0));
                PyDict_SetItem(from_dict, str, _bpy_names(self, code));
                Py_DECREF(str);
            }
        }
    }

    /* create a dummy */
    self_from = PyObject_New(BPy_Library, &bpy_lib_Type);
    BLI_strncpy(self_from->relpath, self->relpath, sizeof(self_from->relpath));
    BLI_strncpy(self_from->abspath, self->abspath, sizeof(self_from->abspath));

    self_from->blo_handle = NULL;
    self_from->flag = 0;
    self_from->dict = from_dict; /* owns the dict */

    /* return pair */
    ret = PyTuple_New(2);

    PyTuple_SET_ITEM(ret, 0, (PyObject *)self_from);

    PyTuple_SET_ITEM(ret, 1, (PyObject *)self);
    Py_INCREF(self);

    BKE_reports_clear(&reports);

    return ret;
}

static void bpy_lib_exit_warn_idname(BPy_Library *self, const char *name_plural, const char *idname)
{
    PyObject *exc, *val, *tb;
    PyErr_Fetch(&exc, &val, &tb);
    if (PyErr_WarnFormat(PyExc_UserWarning, 1,
                         "load: '%s' does not contain %s[\"%s\"]",
                         self->abspath, name_plural, idname)) {
        /* Spurious errors can appear at shutdown */
        if (PyErr_ExceptionMatches(PyExc_Warning)) {
            PyErr_WriteUnraisable((PyObject *)self);
        }
    }
    PyErr_Restore(exc, val, tb);
}

static void bpy_lib_exit_warn_type(BPy_Library *self, PyObject *item)
{
    PyObject *exc, *val, *tb;
    PyErr_Fetch(&exc, &val, &tb);
    if (PyErr_WarnFormat(PyExc_UserWarning, 1,
                         "load: '%s' expected a string type, not a %.200s",
                         self->abspath, Py_TYPE(item)->tp_name)) {
        /* Spurious errors can appear at shutdown */
        if (PyErr_ExceptionMatches(PyExc_Warning)) {
            PyErr_WriteUnraisable((PyObject *)self);
        }
    }
    PyErr_Restore(exc, val, tb);
}

static PyObject *bpy_lib_exit(BPy_Library *self, PyObject *UNUSED(args))
{
    Main *bmain = CTX_data_main(BPy_GetContext());
    Main *mainl = NULL;
    int err = 0;

    flag_all_listbases_ids(LIB_PRE_EXISTING, 1);

    /* here appending/linking starts */
    mainl = BLO_library_append_begin(bmain, &(self->blo_handle), self->relpath);

    {
        int i = 0, code;
        while ((code = BKE_idcode_iter_step(&i))) {
            if (BKE_idcode_is_linkable(code)) {
                const char *name_plural = BKE_idcode_to_name_plural(code);
                PyObject *ls = PyDict_GetItemString(self->dict, name_plural);
                // printf("lib: %s\n", name_plural);
                if (ls && PyList_Check(ls)) {
                    /* loop */
                    Py_ssize_t size = PyList_GET_SIZE(ls);
                    Py_ssize_t i;
                    PyObject *item;
                    const char *item_str;

                    for (i = 0; i < size; i++) {
                        item = PyList_GET_ITEM(ls, i);
                        item_str = _PyUnicode_AsString(item);

                        // printf("  %s\n", item_str);

                        if (item_str) {
                            ID *id = BLO_library_append_named_part(mainl, &(self->blo_handle), item_str, code);
                            if (id) {
#ifdef USE_RNA_DATABLOCKS
                                PointerRNA id_ptr;
                                RNA_id_pointer_create(id, &id_ptr);
                                Py_DECREF(item);
                                item = pyrna_struct_CreatePyObject(&id_ptr);
#endif
                            }
                            else {
                                bpy_lib_exit_warn_idname(self, name_plural, item_str);
                                /* just warn for now */
                                /* err = -1; */
#ifdef USE_RNA_DATABLOCKS
                                item = Py_None;
                                Py_INCREF(item);
#endif
                            }

                            /* ID or None */
                        }
                        else {
                            /* XXX, could complain about this */
                            bpy_lib_exit_warn_type(self, item);
                            PyErr_Clear();

#ifdef USE_RNA_DATABLOCKS
                            item = Py_None;
                            Py_INCREF(item);
#endif
                        }

#ifdef USE_RNA_DATABLOCKS
                        PyList_SET_ITEM(ls, i, item);
#endif
                    }
                }
            }
        }
    }

    if (err == -1) {
        /* exception raised above, XXX, this leaks some memory */
        BLO_blendhandle_close(self->blo_handle);
        self->blo_handle = NULL;
        flag_all_listbases_ids(LIB_PRE_EXISTING, 0);
        return NULL;
    }
    else {
        Library *lib = mainl->curlib; /* newly added lib, assign before append end */
        BLO_library_append_end(NULL, mainl, &(self->blo_handle), 0, self->flag);
        BLO_blendhandle_close(self->blo_handle);
        self->blo_handle = NULL;

        {   /* copied from wm_operator.c */
            /* mark all library linked objects to be updated */
            recalc_all_library_objects(G.main);

            /* append, rather than linking */
            if ((self->flag & FILE_LINK) == 0) {
                BKE_library_make_local(bmain, lib, 1);
            }
        }

        flag_all_listbases_ids(LIB_PRE_EXISTING, 0);

        Py_RETURN_NONE;
    }
}

static PyObject *bpy_lib_dir(BPy_Library *self)
{
    return PyDict_Keys(self->dict);
}


int bpy_lib_init(PyObject *mod_par)
{
    static PyMethodDef load_meth = {"load", (PyCFunction)bpy_lib_load,
                                   METH_STATIC|METH_VARARGS|METH_KEYWORDS,
                                   bpy_lib_load_doc};

    PyModule_AddObject(mod_par, "_library_load", PyCFunction_New(&load_meth, NULL));

    /* some compilers dont like accessing this directly, delay assignment */
    bpy_lib_Type.tp_getattro = PyObject_GenericGetAttr;

    if (PyType_Ready(&bpy_lib_Type) < 0)
        return -1;

    return 0;
}