Welcome to mirror list, hosted at ThFree Co, Russian Federation.

__init__.py « utils « bpy « modules « scripts « release - git.blender.org/blender.git - Unnamed repository; edit this file 'description' to name the repository.
summaryrefslogtreecommitdiff
blob: 58b20d9e3c8623d4621be2cfb20fe023855305e5 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
# ##### 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 #####

# <pep8-80 compliant>

"""
This module contains utility functions specific to blender but
not associated with blenders internal data.
"""

__all__ = (
    "blend_paths",
    "escape_identifier",
    "unescape_identifier",
    "keyconfig_init",
    "keyconfig_set",
    "load_scripts",
    "modules_from_path",
    "preset_find",
    "preset_paths",
    "refresh_script_paths",
    "app_template_paths",
    "register_class",
    "register_manual_map",
    "unregister_manual_map",
    "register_classes_factory",
    "register_submodule_factory",
    "register_tool",
    "make_rna_paths",
    "manual_map",
    "previews",
    "resource_path",
    "script_path_user",
    "script_path_pref",
    "script_paths",
    "smpte_from_frame",
    "smpte_from_seconds",
    "units",
    "unregister_class",
    "unregister_tool",
    "user_resource",
    "execfile",
)

from _bpy import (
    _utils_units as units,
    blend_paths,
    escape_identifier,
    unescape_identifier,
    register_class,
    resource_path,
    script_paths as _bpy_script_paths,
    unregister_class,
    user_resource as _user_resource,
    system_resource,
)

import bpy as _bpy
import os as _os
import sys as _sys

import addon_utils as _addon_utils

_preferences = _bpy.context.preferences
_script_module_dirs = "startup", "modules"
_is_factory_startup = _bpy.app.factory_startup


def execfile(filepath, *, mod=None):
    """
    Execute a file path as a Python script.

    :arg filepath: Path of the script to execute.
    :type filepath: string
    :arg mod: Optional cached module, the result of a previous execution.
    :type mod: Module or None
    :return: The module which can be passed back in as ``mod``.
    :rtype: ModuleType
    """

    import importlib.util
    mod_name = "__main__"
    mod_spec = importlib.util.spec_from_file_location(mod_name, filepath)
    if mod is None:
        mod = importlib.util.module_from_spec(mod_spec)

    # While the module name is not added to `sys.modules`, it's important to temporarily
    # include this so statements such as `sys.modules[cls.__module__].__dict__` behave as expected.
    # See: https://bugs.python.org/issue9499 for details.
    modules = _sys.modules
    mod_orig = modules.get(mod_name, None)
    modules[mod_name] = mod

    # No error supression, just ensure `sys.modules[mod_name]` is properly restored in the case of an error.
    try:
        mod_spec.loader.exec_module(mod)
    finally:
        if mod_orig is None:
            modules.pop(mod_name, None)
        else:
            modules[mod_name] = mod_orig

    return mod


def _test_import(module_name, loaded_modules):
    use_time = _bpy.app.debug_python

    if module_name in loaded_modules:
        return None
    if "." in module_name:
        print("Ignoring '%s', can't import files containing "
              "multiple periods" % module_name)
        return None

    if use_time:
        import time
        t = time.time()

    try:
        mod = __import__(module_name)
    except:
        import traceback
        traceback.print_exc()
        return None

    if use_time:
        print("time %s %.4f" % (module_name, time.time() - t))

    loaded_modules.add(mod.__name__)  # should match mod.__name__ too
    return mod


# Check before adding paths as reloading would add twice.

# Storing and restoring the full `sys.path` is risky as this may be intentionally modified
# by technical users/developers.
#
# Instead, track which paths have been added, clearing them before refreshing.
# This supports the case of loading a new preferences file which may reset scripts path.
_sys_path_ensure_paths = set()


def _sys_path_ensure_prepend(path):
    if path not in _sys.path:
        _sys.path.insert(0, path)
        _sys_path_ensure_paths.add(path)


def _sys_path_ensure_append(path):
    if path not in _sys.path:
        _sys.path.append(path)
        _sys_path_ensure_paths.add(path)


def modules_from_path(path, loaded_modules):
    """
    Load all modules in a path and return them as a list.

    :arg path: this path is scanned for scripts and packages.
    :type path: string
    :arg loaded_modules: already loaded module names, files matching these
       names will be ignored.
    :type loaded_modules: set
    :return: all loaded modules.
    :rtype: list
    """
    modules = []

    for mod_name, _mod_path in _bpy.path.module_names(path):
        mod = _test_import(mod_name, loaded_modules)
        if mod:
            modules.append(mod)

    return modules


_global_loaded_modules = []  # store loaded module names for reloading.
import bpy_types as _bpy_types  # keep for comparisons, never ever reload this.


def load_scripts(*, reload_scripts=False, refresh_scripts=False):
    """
    Load scripts and run each modules register function.

    :arg reload_scripts: Causes all scripts to have their unregister method
       called before loading.
    :type reload_scripts: bool
    :arg refresh_scripts: only load scripts which are not already loaded
       as modules.
    :type refresh_scripts: bool
    """
    use_time = use_class_register_check = _bpy.app.debug_python
    use_user = not _is_factory_startup

    if use_time:
        import time
        t_main = time.time()

    loaded_modules = set()

    if refresh_scripts:
        original_modules = _sys.modules.values()

    if reload_scripts:
        # just unload, don't change user defaults, this means we can sync
        # to reload. note that they will only actually reload of the
        # modification time changes. This `won't` work for packages so...
        # its not perfect.
        for module_name in [ext.module for ext in _preferences.addons]:
            _addon_utils.disable(module_name)

    def register_module_call(mod):
        register = getattr(mod, "register", None)
        if register:
            try:
                register()
            except:
                import traceback
                traceback.print_exc()
        else:
            print("\nWarning! '%s' has no register function, "
                  "this is now a requirement for registerable scripts" %
                  mod.__file__)

    def unregister_module_call(mod):
        unregister = getattr(mod, "unregister", None)
        if unregister:
            try:
                unregister()
            except:
                import traceback
                traceback.print_exc()

    def test_reload(mod):
        import importlib
        # reloading this causes internal errors
        # because the classes from this module are stored internally
        # possibly to refresh internal references too but for now, best not to.
        if mod == _bpy_types:
            return mod

        try:
            return importlib.reload(mod)
        except:
            import traceback
            traceback.print_exc()

    def test_register(mod):

        if refresh_scripts and mod in original_modules:
            return

        if reload_scripts and mod:
            print("Reloading:", mod)
            mod = test_reload(mod)

        if mod:
            register_module_call(mod)
            _global_loaded_modules.append(mod.__name__)

    if reload_scripts:

        # module names -> modules
        _global_loaded_modules[:] = [_sys.modules[mod_name]
                                     for mod_name in _global_loaded_modules]

        # loop over and unload all scripts
        _global_loaded_modules.reverse()
        for mod in _global_loaded_modules:
            unregister_module_call(mod)

        for mod in _global_loaded_modules:
            test_reload(mod)

        del _global_loaded_modules[:]

    from bpy_restrict_state import RestrictBlend

    with RestrictBlend():
        for base_path in script_paths(use_user=use_user):
            for path_subdir in _script_module_dirs:
                path = _os.path.join(base_path, path_subdir)
                if _os.path.isdir(path):
                    _sys_path_ensure_prepend(path)

                    # Only add to 'sys.modules' unless this is 'startup'.
                    if path_subdir == "startup":
                        for mod in modules_from_path(path, loaded_modules):
                            test_register(mod)

    # load template (if set)
    if any(_bpy.utils.app_template_paths()):
        import bl_app_template_utils
        bl_app_template_utils.reset(reload_scripts=reload_scripts)
        del bl_app_template_utils

    # deal with addons separately
    _initialize = getattr(_addon_utils, "_initialize", None)
    if _initialize is not None:
        # first time, use fast-path
        _initialize()
        del _addon_utils._initialize
    else:
        _addon_utils.reset_all(reload_scripts=reload_scripts)
    del _initialize

    if reload_scripts:
        _bpy.context.window_manager.tag_script_reload()

        import gc
        print("gc.collect() -> %d" % gc.collect())

    if use_time:
        print("Python Script Load Time %.4f" % (time.time() - t_main))

    if use_class_register_check:
        for cls in _bpy.types.bpy_struct.__subclasses__():
            if getattr(cls, "is_registered", False):
                for subcls in cls.__subclasses__():
                    if not subcls.is_registered:
                        print(
                            "Warning, unregistered class: %s(%s)" %
                            (subcls.__name__, cls.__name__)
                        )


# base scripts
_scripts = (
    _os.path.dirname(_os.path.dirname(_os.path.dirname(__file__))),
)


def script_path_user():
    """returns the env var and falls back to home dir or None"""
    path = _user_resource('SCRIPTS')
    return _os.path.normpath(path) if path else None


def script_path_pref():
    """returns the user preference or None"""
    path = _preferences.filepaths.script_directory
    return _os.path.normpath(path) if path else None


def script_paths(*, subdir=None, user_pref=True, check_all=False, use_user=True):
    """
    Returns a list of valid script paths.

    :arg subdir: Optional subdir.
    :type subdir: string
    :arg user_pref: Include the user preference script path.
    :type user_pref: bool
    :arg check_all: Include local, user and system paths rather just the paths
       blender uses.
    :type check_all: bool
    :return: script paths.
    :rtype: list
    """
    scripts = list(_scripts)

    # Only paths Blender uses.
    #
    # Needed this is needed even when 'check_all' is enabled,
    # so the 'BLENDER_SYSTEM_SCRIPTS' environment variable will be used.
    base_paths = _bpy_script_paths()

    # Defined to be (system, user) so we can skip the second if needed.
    if not use_user:
        base_paths = base_paths[:1]

    if check_all:
        # All possible paths, no duplicates, keep order.
        if use_user:
            test_paths = ('LOCAL', 'USER', 'SYSTEM')
        else:
            test_paths = ('LOCAL', 'SYSTEM')

        base_paths = (
            *(path for path in (
                _os.path.join(resource_path(res), "scripts")
                for res in test_paths) if path not in base_paths),
            *base_paths,
        )

    test_paths = (
        *base_paths,
        *((script_path_user(),) if use_user else ()),
        *((script_path_pref(),) if user_pref else ()),
    )

    for path in test_paths:
        if path:
            path = _os.path.normpath(path)
            if path not in scripts and _os.path.isdir(path):
                scripts.append(path)

    if subdir is None:
        return scripts

    scripts_subdir = []
    for path in scripts:
        path_subdir = _os.path.join(path, subdir)
        if _os.path.isdir(path_subdir):
            scripts_subdir.append(path_subdir)

    return scripts_subdir


def refresh_script_paths():
    """
    Run this after creating new script paths to update sys.path
    """

    for path in _sys_path_ensure_paths:
        try:
            _sys.path.remove(path)
        except ValueError:
            pass
    _sys_path_ensure_paths.clear()

    for base_path in script_paths():
        for path_subdir in _script_module_dirs:
            path = _os.path.join(base_path, path_subdir)
            if _os.path.isdir(path):
                _sys_path_ensure_prepend(path)

    for path in _addon_utils.paths():
        _sys_path_ensure_append(path)
        path = _os.path.join(path, "modules")
        if _os.path.isdir(path):
            _sys_path_ensure_append(path)


def app_template_paths(*, path=None):
    """
    Returns valid application template paths.

    :arg path: Optional subdir.
    :type path: string
    :return: app template paths.
    :rtype: generator
    """
    subdir_args = (path,) if path is not None else ()
    # Note: keep in sync with: Blender's 'BKE_appdir_app_template_any'.
    # Uses 'BLENDER_USER_SCRIPTS', 'BLENDER_SYSTEM_SCRIPTS'
    # ... in this case 'system' accounts for 'local' too.
    for resource_fn, module_name in (
            (_user_resource, "bl_app_templates_user"),
            (system_resource, "bl_app_templates_system"),
    ):
        path_test = resource_fn('SCRIPTS', path=_os.path.join("startup", module_name, *subdir_args))
        if path_test and _os.path.isdir(path_test):
            yield path_test


def preset_paths(subdir):
    """
    Returns a list of paths for a specific preset.

    :arg subdir: preset subdirectory (must not be an absolute path).
    :type subdir: string
    :return: script paths.
    :rtype: list
    """
    dirs = []
    for path in script_paths(subdir="presets", check_all=True):
        directory = _os.path.join(path, subdir)
        if not directory.startswith(path):
            raise Exception("invalid subdir given %r" % subdir)
        elif _os.path.isdir(directory):
            dirs.append(directory)

    # Find addons preset paths
    for path in _addon_utils.paths():
        directory = _os.path.join(path, "presets", subdir)
        if _os.path.isdir(directory):
            dirs.append(directory)

    return dirs


def is_path_builtin(path):
    """
    Returns True if the path is one of the built-in paths used by Blender.

    :arg path: Path you want to check if it is in the built-in settings directory
    :type path: str
    :rtype: bool
    """
    # Note that this function is is not optimized for speed,
    # it's intended to be used to check if it's OK to remove presets.
    #
    # If this is used in a draw-loop for example, we could cache some of the values.
    user_path = resource_path('USER')

    for res in ('SYSTEM', 'LOCAL'):
        parent_path = resource_path(res)
        if not parent_path or parent_path == user_path:
            # Make sure that the current path is not empty string and that it is
            # not the same as the user config path. IE "~/.config/blender" on Linux
            # This can happen on portable installs.
            continue

        try:
            if _os.path.samefile(
                    _os.path.commonpath([parent_path]),
                    _os.path.commonpath([parent_path, path])
            ):
                return True
        except FileNotFoundError:
            # The path we tried to look up doesn't exist.
            pass
        except ValueError:
            # Happens on Windows when paths don't have the same drive.
            pass

    return False


def smpte_from_seconds(time, *, fps=None, fps_base=None):
    """
    Returns an SMPTE formatted string from the *time*:
    ``HH:MM:SS:FF``.

    If *fps* and *fps_base* are not given the current scene is used.

    :arg time: time in seconds.
    :type time: int, float or ``datetime.timedelta``.
    :return: the frame string.
    :rtype: string
    """

    return smpte_from_frame(
        time_to_frame(time, fps=fps, fps_base=fps_base),
        fps=fps,
        fps_base=fps_base
    )


def smpte_from_frame(frame, *, fps=None, fps_base=None):
    """
    Returns an SMPTE formatted string from the *frame*:
    ``HH:MM:SS:FF``.

    If *fps* and *fps_base* are not given the current scene is used.

    :arg frame: frame number.
    :type frame: int or float.
    :return: the frame string.
    :rtype: string
    """

    if fps is None:
        fps = _bpy.context.scene.render.fps

    if fps_base is None:
        fps_base = _bpy.context.scene.render.fps_base

    fps = fps / fps_base
    sign = "-" if frame < 0 else ""
    frame = abs(frame)

    return (
        "%s%02d:%02d:%02d:%02d" % (
            sign,
            int(frame / (3600 * fps)),          # HH
            int((frame / (60 * fps)) % 60),     # MM
            int((frame / fps) % 60),            # SS
            int(frame % fps),                   # FF
        ))


def time_from_frame(frame, *, fps=None, fps_base=None):
    """
    Returns the time from a frame number .

    If *fps* and *fps_base* are not given the current scene is used.

    :arg frame: number.
    :type frame: int or float.
    :return: the time in seconds.
    :rtype: datetime.timedelta
    """

    if fps is None:
        fps = _bpy.context.scene.render.fps

    if fps_base is None:
        fps_base = _bpy.context.scene.render.fps_base

    fps = fps / fps_base

    from datetime import timedelta

    return timedelta(0, frame / fps)


def time_to_frame(time, *, fps=None, fps_base=None):
    """
    Returns a float frame number from a time given in seconds or
    as a datetime.timedelta object.

    If *fps* and *fps_base* are not given the current scene is used.

    :arg time: time in seconds.
    :type time: number or a ``datetime.timedelta`` object
    :return: the frame.
    :rtype: float
    """

    if fps is None:
        fps = _bpy.context.scene.render.fps

    if fps_base is None:
        fps_base = _bpy.context.scene.render.fps_base

    fps = fps / fps_base

    from datetime import timedelta

    if isinstance(time, timedelta):
        time = time.total_seconds()

    return time * fps


def preset_find(name, preset_path, *, display_name=False, ext=".py"):
    if not name:
        return None

    for directory in preset_paths(preset_path):

        if display_name:
            filename = ""
            for fn in _os.listdir(directory):
                if fn.endswith(ext) and name == _bpy.path.display_name(fn, title_case=False):
                    filename = fn
                    break
        else:
            filename = name + ext

        if filename:
            filepath = _os.path.join(directory, filename)
            if _os.path.exists(filepath):
                return filepath


def keyconfig_init():
    # Key configuration initialization and refresh, called from the Blender
    # window manager on startup and refresh.
    active_config = _preferences.keymap.active_keyconfig

    # Load the default key configuration.
    default_filepath = preset_find("Blender", "keyconfig")
    keyconfig_set(default_filepath)

    # Set the active key configuration if different
    filepath = preset_find(active_config, "keyconfig")

    if filepath and filepath != default_filepath:
        keyconfig_set(filepath)


def keyconfig_set(filepath, *, report=None):
    from os.path import basename, splitext

    if _bpy.app.debug_python:
        print("loading preset:", filepath)

    keyconfigs = _bpy.context.window_manager.keyconfigs

    try:
        error_msg = ""
        execfile(filepath)
    except:
        import traceback
        error_msg = traceback.format_exc()

    name = splitext(basename(filepath))[0]
    kc_new = keyconfigs.get(name)

    if error_msg:
        if report is not None:
            report({'ERROR'}, error_msg)
        print(error_msg)
        if kc_new is not None:
            keyconfigs.remove(kc_new)
        return False

    # Get name, exception for default keymap to keep backwards compatibility.
    if kc_new is None:
        if report is not None:
            report({'ERROR'}, "Failed to load keymap %r" % filepath)
        return False
    else:
        keyconfigs.active = kc_new
        return True


def user_resource(resource_type, *, path="", create=False):
    """
    Return a user resource path (normally from the users home directory).

    :arg type: Resource type in ['DATAFILES', 'CONFIG', 'SCRIPTS', 'AUTOSAVE'].
    :type type: string
    :arg path: Optional subdirectory.
    :type path: string
    :arg create: Treat the path as a directory and create
       it if its not existing.
    :type create: boolean
    :return: a path.
    :rtype: string
    """

    target_path = _user_resource(resource_type, path=path)

    if create:
        # should always be true.
        if target_path:
            # create path if not existing.
            if not _os.path.exists(target_path):
                try:
                    _os.makedirs(target_path)
                except:
                    import traceback
                    traceback.print_exc()
                    target_path = ""
            elif not _os.path.isdir(target_path):
                print("Path %r found but isn't a directory!" % target_path)
                target_path = ""

    return target_path


def register_classes_factory(classes):
    """
    Utility function to create register and unregister functions
    which simply registers and unregisters a sequence of classes.
    """
    def register():
        from bpy.utils import register_class
        for cls in classes:
            register_class(cls)

    def unregister():
        from bpy.utils import unregister_class
        for cls in reversed(classes):
            unregister_class(cls)

    return register, unregister


def register_submodule_factory(module_name, submodule_names):
    """
    Utility function to create register and unregister functions
    which simply load submodules,
    calling their register & unregister functions.

    .. note::

       Modules are registered in the order given,
       unregistered in reverse order.

    :arg module_name: The module name, typically ``__name__``.
    :type module_name: string
    :arg submodule_names: List of submodule names to load and unload.
    :type submodule_names: list of strings
    :return: register and unregister functions.
    :rtype: tuple pair of functions
    """

    module = None
    submodules = []

    def register():
        nonlocal module
        module = __import__(name=module_name, fromlist=submodule_names)
        submodules[:] = [getattr(module, name) for name in submodule_names]
        for mod in submodules:
            mod.register()

    def unregister():
        from sys import modules
        for mod in reversed(submodules):
            mod.unregister()
            name = mod.__name__
            delattr(module, name.partition(".")[2])
            del modules[name]
        submodules.clear()

    return register, unregister


# -----------------------------------------------------------------------------
# Tool Registration


def register_tool(tool_cls, *, after=None, separator=False, group=False):
    """
    Register a tool in the toolbar.

    :arg tool: A tool subclass.
    :type tool: :class:`bpy.types.WorkSpaceTool` subclass.
    :arg space_type: Space type identifier.
    :type space_type: string
    :arg after: Optional identifiers this tool will be added after.
    :type after: collection of strings or None.
    :arg separator: When true, add a separator before this tool.
    :type separator: bool
    :arg group: When true, add a new nested group of tools.
    :type group: bool
    """
    space_type = tool_cls.bl_space_type
    context_mode = tool_cls.bl_context_mode

    from bl_ui.space_toolsystem_common import (
        ToolSelectPanelHelper,
        ToolDef,
    )

    cls = ToolSelectPanelHelper._tool_class_from_space_type(space_type)
    if cls is None:
        raise Exception("Space type %r has no toolbar" % space_type)
    tools = cls._tools[context_mode]

    # First sanity check
    from bpy.types import WorkSpaceTool
    tools_id = {
        item.idname for item in ToolSelectPanelHelper._tools_flatten(tools)
        if item is not None
    }
    if not issubclass(tool_cls, WorkSpaceTool):
        raise Exception("Expected WorkSpaceTool subclass, not %r" % type(tool_cls))
    if tool_cls.bl_idname in tools_id:
        raise Exception("Tool %r already exists!" % tool_cls.bl_idname)
    del tools_id, WorkSpaceTool

    # Convert the class into a ToolDef.
    def tool_from_class(tool_cls):
        # Convert class to tuple, store in the class for removal.
        tool_def = ToolDef.from_dict({
            "idname": tool_cls.bl_idname,
            "label": tool_cls.bl_label,
            "description": getattr(tool_cls, "bl_description", tool_cls.__doc__),
            "icon": getattr(tool_cls, "bl_icon", None),
            "cursor": getattr(tool_cls, "bl_cursor", None),
            "widget": getattr(tool_cls, "bl_widget", None),
            "keymap": getattr(tool_cls, "bl_keymap", None),
            "data_block": getattr(tool_cls, "bl_data_block", None),
            "operator": getattr(tool_cls, "bl_operator", None),
            "draw_settings": getattr(tool_cls, "draw_settings", None),
            "draw_cursor": getattr(tool_cls, "draw_cursor", None),
        })
        tool_cls._bl_tool = tool_def

        keymap_data = tool_def.keymap
        if keymap_data is not None:
            if context_mode is None:
                context_descr = "All"
            else:
                context_descr = context_mode.replace("_", " ").title()
            from bpy import context
            wm = context.window_manager
            keyconfigs = wm.keyconfigs
            kc_default = keyconfigs.default
            # Note that Blender's default tools use the default key-config for both.
            # We need to use the add-ons for 3rd party tools so reloading the key-map doesn't clear them.
            kc = keyconfigs.addon
            if callable(keymap_data[0]):
                cls._km_action_simple(kc_default, kc, context_descr, tool_def.label, keymap_data)
        return tool_def

    tool_converted = tool_from_class(tool_cls)

    if group:
        # Create a new group
        tool_converted = (tool_converted,)

    tool_def_insert = (
        (None, tool_converted) if separator else
        (tool_converted,)
    )

    def skip_to_end_of_group(seq, i):
        i_prev = i
        while i < len(seq) and seq[i] is not None:
            i_prev = i
            i += 1
        return i_prev

    changed = False
    if after is not None:
        for i, item in enumerate(tools):
            if item is None:
                pass
            elif isinstance(item, ToolDef):
                if item.idname in after:
                    i = skip_to_end_of_group(item, i)
                    tools[i + 1:i + 1] = tool_def_insert
                    changed = True
                    break
            elif isinstance(item, tuple):
                for j, sub_item in enumerate(item, 1):
                    if isinstance(sub_item, ToolDef):
                        if sub_item.idname in after:
                            if group:
                                # Can't add a group within a group,
                                # add a new group after this group.
                                i = skip_to_end_of_group(tools, i)
                                tools[i + 1:i + 1] = tool_def_insert
                            else:
                                j = skip_to_end_of_group(item, j)
                                item = item[:j + 1] + tool_def_insert + item[j + 1:]
                                tools[i] = item
                            changed = True
                            break
                if changed:
                    break

        if not changed:
            print("bpy.utils.register_tool: could not find 'after'", after)
    if not changed:
        tools.extend(tool_def_insert)


def unregister_tool(tool_cls):
    space_type = tool_cls.bl_space_type
    context_mode = tool_cls.bl_context_mode

    from bl_ui.space_toolsystem_common import ToolSelectPanelHelper
    cls = ToolSelectPanelHelper._tool_class_from_space_type(space_type)
    if cls is None:
        raise Exception("Space type %r has no toolbar" % space_type)
    tools = cls._tools[context_mode]

    tool_def = tool_cls._bl_tool
    try:
        i = tools.index(tool_def)
    except ValueError:
        i = -1

    def tool_list_clean(tool_list):
        # Trim separators.
        while tool_list and tool_list[-1] is None:
            del tool_list[-1]
        while tool_list and tool_list[0] is None:
            del tool_list[0]
        # Remove duplicate separators.
        for i in range(len(tool_list) - 1, -1, -1):
            is_none = tool_list[i] is None
            if is_none and prev_is_none:
                del tool_list[i]
            prev_is_none = is_none

    changed = False
    if i != -1:
        del tools[i]
        tool_list_clean(tools)
        changed = True

    if not changed:
        for i, item in enumerate(tools):
            if isinstance(item, tuple):
                try:
                    j = item.index(tool_def)
                except ValueError:
                    j = -1

                if j != -1:
                    item_clean = list(item)
                    del item_clean[j]
                    tool_list_clean(item_clean)
                    if item_clean:
                        tools[i] = tuple(item_clean)
                    else:
                        del tools[i]
                        tool_list_clean(tools)
                    del item_clean

                    # tuple(sub_item for sub_item in items if sub_item is not tool_def)
                    changed = True
                    break

    if not changed:
        raise Exception("Unable to remove %r" % tool_cls)
    del tool_cls._bl_tool

    keymap_data = tool_def.keymap
    if keymap_data is not None:
        from bpy import context
        wm = context.window_manager
        keyconfigs = wm.keyconfigs
        for kc in (keyconfigs.default, keyconfigs.addon):
            km = kc.keymaps.get(keymap_data[0])
            if km is None:
                print("Warning keymap %r not found in %r!" % (keymap_data[0], kc.name))
            else:
                kc.keymaps.remove(km)


# -----------------------------------------------------------------------------
# Manual lookups, each function has to return a basepath and a sequence
# of...

# we start with the built-in default mapping
def _blender_default_map():
    import rna_manual_reference as ref_mod
    ret = (ref_mod.url_manual_prefix, ref_mod.url_manual_mapping)
    # avoid storing in memory
    del _sys.modules["rna_manual_reference"]
    return ret


# hooks for doc lookups
_manual_map = [_blender_default_map]


def register_manual_map(manual_hook):
    _manual_map.append(manual_hook)


def unregister_manual_map(manual_hook):
    _manual_map.remove(manual_hook)


def manual_map():
    # reverse so default is called last
    for cb in reversed(_manual_map):
        try:
            prefix, url_manual_mapping = cb()
        except:
            print("Error calling %r" % cb)
            import traceback
            traceback.print_exc()
            continue

        yield prefix, url_manual_mapping


# Build an RNA path from struct/property/enum names.
def make_rna_paths(struct_name, prop_name, enum_name):
    """
    Create RNA "paths" from given names.

    :arg struct_name: Name of a RNA struct (like e.g. "Scene").
    :type struct_name: string
    :arg prop_name: Name of a RNA struct's property.
    :type prop_name: string
    :arg enum_name: Name of a RNA enum identifier.
    :type enum_name: string
    :return: A triple of three "RNA paths"
       (most_complete_path, "struct.prop", "struct.prop:'enum'").
       If no enum_name is given, the third element will always be void.
    :rtype: tuple of strings
    """
    src = src_rna = src_enum = ""
    if struct_name:
        if prop_name:
            src = src_rna = ".".join((struct_name, prop_name))
            if enum_name:
                src = src_enum = "%s:'%s'" % (src_rna, enum_name)
        else:
            src = src_rna = struct_name
    return src, src_rna, src_enum