File: schema.py

package info (click to toggle)
dataclass-wizard 0.39.1-1
  • links: PTS, VCS
  • area: main
  • in suites: forky, sid
  • size: 3,112 kB
  • sloc: python: 19,560; makefile: 126; javascript: 23
file content (1109 lines) | stat: -rw-r--r-- 34,983 bytes parent folder | download
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
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
"""
Generates a Python (dataclass) schema, given a JSON input. The entry point for
this module is the `gen-schema` subcommand.

This JSON to Dataclass conversion tool was inspired by the following projects:

    * https://github.com/mischareitsma/json2dataclass
    * https://github.com/russbiggs/json2dataclass
    * https://github.com/mholt/json-to-go

The parser supports the full JSON spec, so both `list` and `dict` as the
root type are properly handled as expected.

A few important notes on the behavior of JSON parsing:

    * Lists with multiple dictionaries will have all the keys and type
      definitions merged into a single model dataclass, as the dictionary
      objects are considered homogenous in this case.

    * Nested lists within the above structure (e.g. list -> dict -> list)
      should similarly merge all list elements with the list for that same key
      in each sibling `dict` object. For example, assuming the below input::
        ... [{"d1": [1, {"k": "v"}]}, {"d1": [{"k": 2}, {"k2": "v2"}, True]}]
      This should result in a single, merged type definition for "d1"::
        ... List[Union[int, dataclass(k: Union[str, int], k2: str), bool]]

    * Any nested dictionaries within lists will have their Model class name
      generated with the singular form of the key containing the model
      definition -- for example, {"Items":[{"key":"value"}]} will result in a
      model class named `Item`. In the case a dictionary is nested within a
      list, it will have the class name auto-incremented with a common
      prefix -- for example, `Data1`, `Data2`, etc.


The implementation below uses regex code in the `rules.english` module from
the library Python-Inflector (https://github.com/bermi/Python-Inflector).

This library is available under the BSD license, which can be
obtained from https://opensource.org/licenses.

The library Python-Inflector contains the following attribution notices:

    Copyright (c) 2006 Bermi Ferrer Martinez
    bermi a-t bermilabs - com

See the end of this file for the original BSD-style license from this library.

"""

__all__ = [
    'PyCodeGenerator'
]

import json
import re
import textwrap
from collections import defaultdict
from collections import deque
from collections.abc import Iterable
from dataclasses import dataclass, field, InitVar
from datetime import date, datetime, time
from enum import Enum
from pathlib import Path
from typing import Callable, Any, Optional, TypeVar, Type, ClassVar
from typing import DefaultDict, Set, List
from typing import (
    Union, Dict, Sequence
)

from .. import property_wizard
from ..constants import PACKAGE_NAME
from ..class_helper import get_class_name
from ..type_def import PyDeque, JSONList, JSONObject, JSONValue, T
from ..utils.string_conv import to_snake_case, to_pascal_case
# noinspection PyProtectedMember
from ..utils.type_conv import TRUTHY_VALUES
from ..utils.type_conv import as_datetime, as_date, as_time


# Some unconstrained type variables.  These are used by the container types.
# (These are not for export.)
_S = TypeVar('_S')

# Merge both the "truthy" and "falsy" values, so we can determine the criteria
# under which a string can be considered as a boolean value.
_FALSY_VALUES = {'false', 'f', 'no', 'n', 'off', '0'}
_BOOL_VALUES = TRUTHY_VALUES | _FALSY_VALUES

# Valid types for JSON contents; this can be either a list of any type,
# or a dictionary with `string` keys and values of any type.
JSONBlobType = Union[JSONList, JSONObject]

PyDataTypeOrSeq = Union['PyDataType', Sequence['PyDataType']]
TypeContainerElements = Union[PyDataTypeOrSeq,
                              'PyDataclassGenerator', 'PyListGenerator']


@dataclass
class PyCodeGenerator:
    """
    This is the main class responsible for generating Python code that
    leverages dataclasses, given a JSON object as an input data.
    """

    # Either the file name (ex. file1.json) or the file contents as a string
    # can be passed in as an input to the constructor method.
    file_name: InitVar[str] = None
    file_contents: InitVar[str] = None

    # Should we force-resolve inferred types for strings? For example, a value
    # of "TRUE" will appear as a `Union[str, bool]` type by default.
    force_strings: InitVar[bool] = None

    # Enable experimental features via a `__future__` import, which allows
    # PEP-585 and PEP-604 style annotations in Python 3.7+
    experimental: InitVar[bool] = None

    # The rest of these fields are just for internal use.
    parser: 'JSONRootParser' = field(init=False)
    data: JSONBlobType = field(init=False)
    _py_code_lines: List[str] = field(default=None, init=False)

    def __post_init__(self, file_name: str, file_contents: str,
                      force_strings: bool, experimental: bool):

        # Set global flags
        global Globals
        Globals = _Globals(force_strings=force_strings,
                           experimental=experimental)

        # https://stackoverflow.com/a/62940588/10237506
        if file_name:
            file_path = Path(file_name)
            file_contents = file_path.read_bytes()

        self.data = json.loads(file_contents)
        self.parser = JSONRootParser(self.data)

    @property
    def py_code(self) -> str:

        if self._py_code_lines is None:
            # Generate Python code for the dataclass(es)
            dataclass_code: str = repr(self.parser)
            # Add any imports used at the top of the code
            self._py_code_lines = ModuleImporter.imports
            if self._py_code_lines:
                self._py_code_lines.append('')
            # Generate final Python code - imports + dataclass(es)
            self._py_code_lines.append(dataclass_code)

        return '\n'.join(self._py_code_lines)


# Global flags (generally passed in via command-line) which are shared by
# classes and functions.
Globals: '_Globals | None' = None


@dataclass
class _Globals:

    # Should we force-resolve inferred types for strings? For example, a value
    # of "TRUE" will appear as a `Union[str, bool]` type by default.
    force_strings: bool = False

    # Enable experimental features via a `__future__` import, which allows
    # PEP-585 and PEP-604 style annotations in Python 3.7+
    experimental: bool = False

    # Should we insert auto-generated comments under each dataclass.
    insert_comments: bool = True

    # Should we include a newline after the comments block mentioned above.
    newline_after_class_def: bool = True


# Credits: https://github.com/bermi/Python-Inflector
class English:
    """
    Inflector for pluralize and singularize English nouns.

    This is the default Inflector for the Inflector obj
    """

    @staticmethod
    def humanize(word):
        """
        Returns a human-readable string from word, by replacing
        underscores with a space, and by upper-casing the initial
        character by default.
        """
        return to_snake_case(word).replace('_', ' ').title()

    @staticmethod
    def singularize(word):
        """Singularizes English nouns."""

        rules = [
            ['(?i)(quiz)zes$', '\\1'],
            ['(?i)(matr)ices$', '\\1ix'],
            ['(?i)(vert|ind)ices$', '\\1ex'],
            ['(?i)^(ox)en', '\\1'],
            ['(?i)(alias|status)es$', '\\1'],
            ['(?i)([octop|vir])i$', '\\1us'],
            ['(?i)(cris|ax|test)es$', '\\1is'],
            ['(?i)(shoe)s$', '\\1'],
            ['(?i)(o)es$', '\\1'],
            ['(?i)(bus)es$', '\\1'],
            ['(?i)([m|l])ice$', '\\1ouse'],
            ['(?i)(x|ch|ss|sh)es$', '\\1'],
            ['(?i)(m)ovies$', '\\1ovie'],
            ['(?i)(s)eries$', '\\1eries'],
            ['(?i)([^aeiouy]|qu)ies$', '\\1y'],
            ['(?i)([lr])ves$', '\\1f'],
            ['(?i)(tive)s$', '\\1'],
            ['(?i)(hive)s$', '\\1'],
            ['(?i)([^f])ves$', '\\1fe'],
            ['(?i)(^analy)ses$', '\\1sis'],
            ['(?i)(^analysis)$', '\\1'],
            ['(?i)((a)naly|(b)a|(d)iagno|(p)arenthe|(p)rogno|(s)ynop|(t)he)ses$', '\\1\\2sis'],
            # I don't want 'Data' replaced with 'Datum', however
            ['(?i)(^data)$', '\\1'],
            ['(?i)([ti])a$', '\\1um'],
            ['(?i)(n)ews$', '\\1ews'],
            ['(?i)s$', ''],
        ]

        uncountable_words = ['equipment', 'information', 'rice', 'money',
                             'species', 'series', 'fish', 'sheep', 'sms']

        irregular_words = {
            'people': 'person',
            'men': 'man',
            'children': 'child',
            'sexes': 'sex',
            'moves': 'move'
        }

        lower_cased_word = word.lower()

        for uncountable_word in uncountable_words:
            if lower_cased_word[-1 * len(uncountable_word):] == uncountable_word:
                return word

        for irregular in irregular_words.keys():
            match = re.search('(' + irregular + ')$', word, re.IGNORECASE)
            if match:
                return re.sub(
                    '(?i)' + irregular + '$',
                    match.expand('\\1')[0] + irregular_words[irregular][1:],
                    word)

        for rule in range(len(rules)):
            match = re.search(rules[rule][0], word, re.IGNORECASE)
            if match:
                groups = match.groups()
                for k in range(0, len(groups)):
                    if groups[k] == None:
                        rules[rule][1] = rules[
                            rule][1].replace('\\' + str(k + 1), '')

                return re.sub(rules[rule][0], rules[rule][1], word)

        return word


# noinspection SpellCheckingInspection, PyPep8Naming
class classproperty:
    """
    Decorator that converts a method with a single cls argument into a
    property that can be accessed directly from the class.

    Credits:
        - https://stackoverflow.com/a/57055258/10237506
        - https://docs.djangoproject.com/en/3.1/ref/utils/#django.utils.functional.classproperty

    """
    def __init__(self, method: Callable[[Any], T]) -> None:
        self.f = method

    def __get__(
            self, instance: Optional[_S], cls: Optional[Type[_S]] = None) -> T:
        return self.f(cls)

    def getter(self, method):
        self.f = method
        return self


def is_float(s: str) -> bool:
    """
    Check if a string is a :class:`float` value
      ex. '1.23'
    """
    try:
        _ = float(s)
        return True
    except ValueError:
        return False


def can_be_bool(o: str) -> bool:
    """
    Check if a string can be a :class:`bool` value. Note this doesn't mean
    that the string can or should be converted to bool, only that it *appears*
    to be one.

    """
    return o.lower() in _BOOL_VALUES


class PyDataType(Enum):
    """
    Enum representing a Python Data Type
    """
    STRING = str
    FLOAT = float
    INT = int
    BOOL = bool
    LIST = list
    DICT = dict
    DATE = date
    DATETIME = datetime
    TIME = time
    NULL = None

    def __str__(self) -> str:
        """
        Returns the string representation of an Enum member's value.
        """
        return getattr(
            self.value, '__name__', str(self.value))


class ModuleImporter:
    """
    Helper class responsible for constructing import statements in the
    generated Python code.
    """

    # Import level (e.g. stdlib or 3rd party) -> Module Name -> Module Imports
    _MOD_IMPORTS: DefaultDict[int, DefaultDict[str, Set[str]]] = defaultdict(
        lambda: defaultdict(set)
    )

    # noinspection PyMethodParameters
    @classproperty
    def imports(cls: Type[T]) -> List[str]:
        """
        Returns a list of generated import statements based on the modules
        currently used in the code.
        """

        lines = []

        for lvl in sorted(cls._MOD_IMPORTS):
            modules = cls._MOD_IMPORTS[lvl]
            for mod in sorted(modules):
                imported = sorted(modules[mod])
                lines.append(f'from {mod} import {", ".join(imported)}')
            lines.append('')

        return lines

    @classmethod
    def wrap_string_with_import(cls, string: str,
                                imported: object,
                                wrap_chars='[]',
                                register_import=True,
                                level=1) -> str:
        """
        Wraps `string` so it is contained within `imported`. The `wrap_chars`
        parameter determines the enclosing characters to use -- defaults to
        braces by default, as subscripted type Generics often appear in this
        form.

        If `register_import` is true (default), an import statement will also
        be generated for the `imported` usage, if one needs to be added.

        Examples::

            >>> ModuleImporter.wrap_string_with_import('int', List)
            'List[int]'

        """

        module = imported.__module__
        name = cls._get_import_name(imported)
        start, end = wrap_chars

        if register_import:
            cls.register_import_by_name(module, name, level)

        return f'{name}{start}{string}{end}'

    # noinspection PyUnresolvedReferences
    @classmethod
    def wrap_with_import(cls, deck: PyDeque[str],
                         imported: object,
                         wrap_chars='[]',
                         register_import=True,
                         level=1) -> None:
        """
        Same as :meth:`wrap_string_with_import` above, except this accepts
        a list (deque) of strings to be wrapped instead.
        """

        module = imported.__module__
        name = cls._get_import_name(imported)
        start, end = wrap_chars

        if register_import:
            cls.register_import_by_name(module, name, level)

        deck.appendleft(start)
        deck.appendleft(name)
        deck.append(end)

    @classmethod
    def register_import(cls, imported: object, level=1) -> None:
        """
        Registers a new import for the given object.

        Examples::

            >>> ModuleImporter.register_import(datetime)

        """

        module = imported.__module__
        name = cls._get_import_name(imported)

        cls.register_import_by_name(module, name, level)

    @classmethod
    def register_import_by_name(cls, module: str, name: str, level: int) -> None:
        """
        Registers a new import for a module and the imported name.

        Note: any built-in's like "int" or "min" should be skipped by
        default.
        """

        # Skip any built-in helper functions
        #   if name in __builtins__.__dict__:
        if module == 'builtins':
            return

        cls._MOD_IMPORTS[level][module].add(name)

    @classmethod
    def register_future_import(cls, name: str) -> None:
        """
        Registers a top-level `__future__` import for a module, which is
        required to be the first import defined at the top of the file.

        """
        cls._MOD_IMPORTS[0]['__future__'].add(name)

    @classmethod
    def clear_imports(cls):
        """
        Clears all the module imports currently in the cache.
        """

        cls._MOD_IMPORTS.clear()

    @classmethod
    def _get_import_name(cls, imported: Any) -> str:
        """Retrieves the name of an imported object."""
        return cls._safe_get_class_name(imported)

    @staticmethod
    def _safe_get_class_name(cls: Any):
        """
        Retrieves the class name of the specified object or class.

        Note: the `_name` attribute is specific to most Generic types in
        the `typing` module.
        """

        try:
            return cls._name

        except AttributeError:
            # Useful to strip underscores from the start, for example
            # in Python 3.6 which doesn't have a `_name` attribute for the
            # `Union` type, and the class name is returned as `_Union`.
            return get_class_name(cls).lstrip('_')


@dataclass(repr=False)
class TypeContainer(List[TypeContainerElements]):
    """
    Custom list class which functions as a container for Python data types.
    """

    # This keeps track of whether we've seen a `null` type before.
    is_optional = False

    def append(self, o: TypeContainerElements):
        """
        Appends an object (or a sequence of objects) to the
        :class:`TypeContainer` instance.
        """

        if isinstance(o, Iterable):
            for elem in o:
                self.append(elem)
            return

        if o is PyDataType.NULL:
            self.is_optional = True
            return

        if o in self:
            return

        if isinstance(o, PyDataType):
            # Register the types in case they are not standard imports.
            # For example, `uuid` and `datetime` objects.
            ModuleImporter.register_import(o.value)

        super(TypeContainer, self).append(o)

    def __or__(self, other):
        """
        Performs logical OR, to merge instances of :class:`TypeContainer`
        """

        if not isinstance(other, TypeContainer):
            raise TypeError(
                f'TypeContainer: incorrect type for __add__: {type(other)}')

        # Remember to carry over the `is_optional` flag
        self.is_optional |= other.is_optional

        if len(self) == 1 and len(other) == 1:
            self_item = self[0]
            other_item = other[0]

            for typ in PyDataclassGenerator, PyListGenerator:
                if isinstance(self_item, typ) and isinstance(other_item, typ):
                    # We call  `__or__` to merge the lists or dataclasses
                    # together.
                    self_item |= other_item

                    return self

        for elem in other:
            self.append(elem)

        return self

    def __repr__(self):
        """
        Iteratively calls the `repr` method of all our model collection types.
        """

        lines = []

        for typ in self:
            if isinstance(typ, (PyDataclassGenerator, PyListGenerator)):
                lines.append(repr(typ))

        return '\n'.join(lines)

    def __str__(self):
        ...

    def _default_str(self):
        """
        Return the string representation of the resolved type -
          ex.`Optional[Union[str, int]]`

        """

        # I'm using `deque`s here to avoid doing `list.insert(0, x)` or later
        # iterating over `reversed(list)`, as this might be a bit faster.
        # noinspection PyUnresolvedReferences
        typing_imports: PyDeque[object] = deque()
        # noinspection PyUnresolvedReferences
        parts: PyDeque[str]

        if not self:
            # This is the case when the only value encountered for a field is
            # a `null` - hence, we're unable to determine the type.
            typing_imports.appendleft(Any)

        elif self.is_optional:
            typing_imports.appendleft(Optional)

        if len(self) > 1:
            # Else, if we have more than one type for a field, then the
            # resolved type should be a `Union` of all the seen types.
            typing_imports.appendleft(Union)

        parts = deque(', '.join(str(typ) for typ in self))

        for tp in typing_imports:
            ModuleImporter.wrap_with_import(parts, tp)

        return ''.join(parts).replace('[]', '')

    def _experimental_features_str(self):

        if not self:
            # This is the case when the only value encountered for a field is
            # a `null` - hence, we're unable to determine the type.
            ModuleImporter.register_import(Any)
            return 'Any'

        parts = [str(typ) for typ in self]
        if self.is_optional:
            parts.append('None')

        return ' | '.join(parts)


def possible_types_for_string_value(string: str) -> PyDataTypeOrSeq:
    """
    Returns possible types for a JSON field with a :class:`string` value,
    depending on what that value appears to be.

    If `Globals.force_strings` is true and there is more than one possible
    type, we simply return the inferred type, instead of the
    `Union[T..., str]` syntax.
    """

    exc_types = TypeError, ValueError

    try:
        _ = as_date(string)
        return PyDataType.DATE
    except exc_types:
        pass

    # I want to eliminate false positives so this seems the easiest
    # way to do that. Otherwise strings like "24" seem to get parsed
    # as a :class:`Time` object, which might not be expected.
    if ':' not in string:
        possible_types = []

        if string.isnumeric():
            possible_types.append(PyDataType.INT)

        elif is_float(string):
            possible_types.append(PyDataType.FLOAT)

        elif can_be_bool(string):
            possible_types.append(PyDataType.BOOL)

        # If force-resolve is enabled, just return the inferred type if one
        # was determined.
        # noinspection PyUnresolvedReferences
        if Globals.force_strings and possible_types:
            return possible_types[0]

        possible_types.append(PyDataType.STRING)

        return possible_types

    try:
        _ = as_time(string)
        return PyDataType.TIME
    except exc_types:
        pass

    try:
        _ = as_datetime(string)
        return PyDataType.DATETIME
    except exc_types:
        pass

    return PyDataType.STRING


def json_to_python_type(o: JSONValue) -> PyDataTypeOrSeq:
    """
    Convert a JSON object to a Python Data Type, or a Union of Python Data
    Types.
    """

    if o is None:
        return PyDataType.NULL

    if isinstance(o, str):
        return possible_types_for_string_value(o)

    # `bool` needs to come before `int`, as it's a subclass of `int`
    if isinstance(o, bool):
        return PyDataType.BOOL

    if isinstance(o, int):
        return PyDataType.INT

    if isinstance(o, float):
        return PyDataType.FLOAT

    if isinstance(o, list):
        return PyDataType.LIST

    if isinstance(o, dict):
        return PyDataType.DICT


@dataclass
class JSONRootParser:

    data: JSONBlobType

    model: Union['PyListGenerator',
                 'PyDataclassGenerator'] = field(init=False)

    def __post_init__(self):

        # Clear imports from last run
        ModuleImporter.clear_imports()

        str_method_prefix = 'default'

        # Check if experimental features are enabled
        if Globals.experimental:
            # Add the required `__future__` import
            ModuleImporter.register_future_import('annotations')
            # Update how annotations are resolved
            str_method_prefix = 'experimental_features'

        # Set the `__str__` method to use for classes
        str_method_name = f'_{str_method_prefix}_str'
        for typ in TypeContainer, PyListGenerator, PyDataclassGenerator:
            typ.__str__ = getattr(typ, str_method_name)

        # We'll need an import for the @dataclass decorator, at a minimum
        ModuleImporter.register_import(dataclass)

        if isinstance(self.data, list):
            self.model = PyListGenerator(self.data,
                                         is_root=True)

        elif isinstance(self.data, dict):
            self.model = PyDataclassGenerator(self.data,
                                              is_root=True)

        else:
            raise TypeError(
                'Incorrect type, expected a JSON `list` or `dict`. '
                f'actual_type={type(self.data)!r}, data={self.data!r}')

    def __repr__(self):
        return repr(self.model) + '\n'


@dataclass
class PyDataclassGenerator(metaclass=property_wizard):

    data: InitVar[JSONObject]

    _name: str = 'data'
    indent: str = ' ' * 4
    is_root: bool = False

    nested_lvl: InitVar[int] = 0

    parsed_types: DefaultDict[str, TypeContainer] = field(
        init=False,
        default_factory=lambda: defaultdict(TypeContainer)
    )

    @property
    def name(self):
        return self._name

    @name.setter
    def name(self, name: str):
        """Title case the name"""
        self._name = to_pascal_case(name)

    @classmethod
    def load_parsed(
            cls: Type[T],
            parsed_types: Dict[str,
                               Union[PyDataType, 'PyDataclassGenerator']],
            **constructor_kwargs
    ) -> T:

        obj = cls({}, **constructor_kwargs)

        for k, typ in parsed_types.items():
            underscored_field = to_snake_case(k)
            obj.parsed_types[underscored_field].append(typ)

        return obj

    def __post_init__(self, data: JSONObject, nested_lvl: int):

        for k, v in data.items():
            underscored_field = to_snake_case(k)
            typ = json_to_python_type(v)

            if typ is PyDataType.DICT:
                typ = PyDataclassGenerator(
                    v, k,
                    nested_lvl=nested_lvl,
                )
            elif typ is PyDataType.LIST:
                nested_lvl += 1
                typ = PyListGenerator(
                    v, k, k,
                    nested_lvl=nested_lvl,
                )

            self.parsed_types[underscored_field].append(typ)

    def __or__(self, other):
        if not isinstance(other, PyDataclassGenerator):
            raise TypeError(
                f'{self.__class__.__name__}: Incorrect type for `__or__`. '
                f'actual_type: {type(other)}, object={other}')

        for k, v in other.parsed_types.items():
            if k in self.parsed_types:
                self.parsed_types[k] |= v

            else:
                self.parsed_types[k] = v

        return self

    def get_lines(self) -> List[str]:
        if self.is_root:
            ModuleImporter.register_import_by_name(
                PACKAGE_NAME, 'JSONWizard', level=2)
            class_name = f'class {self.name}(JSONWizard):'
        else:
            class_name = f'class {self.name}:'

        class_parts = ['@dataclass',
                       class_name]
        parts = []
        nested_parts = []

        # noinspection PyUnresolvedReferences
        if Globals.insert_comments:
            class_parts.append(
                textwrap.indent('"""', self.indent))
            class_parts.append(
                textwrap.indent(f'{self.name} dataclass', self.indent))

            # noinspection PyUnresolvedReferences
            if Globals.newline_after_class_def:
                class_parts.append('')

            class_parts.append(textwrap.indent(
                '"""', self.indent))

        for k, v in self.parsed_types.items():
            line = f'{k}: {v}'
            wrapped_line = textwrap.indent(line, self.indent)
            parts.append(wrapped_line)

            nested_part = repr(v)
            if nested_part:
                nested_parts.append(nested_part)

        for part in nested_parts:
            parts.append('\n')
            parts.append(part)

        if not parts:
            parts = [textwrap.indent('pass', self.indent)]

        class_parts.extend(parts)

        return class_parts

    def __str__(self):
        ...

    def _default_str(self):
        return f"'{self.name}'"

    def _experimental_features_str(self):
        return self.name

    def __repr__(self):
        """
        Returns the Python `dataclasses` representation of the object.
        """
        return '\n'.join(self.get_lines())


@dataclass(repr=False)
class PyListGenerator(metaclass=property_wizard):
    """
    Parse a list in a JSON object to a Python list, based on the following
    rules:

    * If the JSON list contains *only* simple types, for example int,
      str, or bool, then invoking ``str()`` on this object should return
      a Union representation of those types, for example
      `Union[int, str, bool]`.

    * If the JSON list contains *any* complex type, like a dict, then
      all `dict`s should have their keys and values merged together.
      Optional and Union should be included if needed.

      Additionally, if `is_root` is true, then calling ``str()`` will
      effectively ignore any simple types,

    """

    # Default name for model class if none is provided.
    default_name: ClassVar[str] = 'data'

    data: JSONList

    container_name: str = 'container'
    _name: str = None

    indent: str = ' ' * 4

    is_root: InitVar[bool] = False
    nested_lvl: InitVar[int] = 0

    root: PyDataclassGenerator = field(init=False, default=None)

    parsed_types: TypeContainer = field(init=False,
                                        default_factory=TypeContainer)

    # Model is our model dataclass object, which may or may not be present
    # in the list. If there are multiple models (i.e. dicts), their keys
    # and the associated type defs should be merged into one model.
    model: PyDataclassGenerator = field(init=False, default=None)

    @property
    def name(self):
        return self._name

    @name.setter
    def name(self, name: Optional[str]):
        """Title case and singularize the name."""
        if name:
            name = English.humanize(name)
            name = English.singularize(name).replace(' ', '')

        self._name = name

    def __post_init__(self, is_root: bool, nested_lvl: int):

        if not self.name:
            # Increment the suffix if needed
            if nested_lvl:
                self.name = f'{self.default_name}{nested_lvl}'
            else:
                self.name = self.default_name

        # Temp data dictionary object
        data_list = []

        for elem in self.data:

            typ = json_to_python_type(elem)

            if typ is PyDataType.DICT:

                typ = PyDataclassGenerator(elem, self.name,
                                           nested_lvl=nested_lvl,
                                           is_root=is_root)

                if self.model:
                    self.model |= typ
                    continue

                self.model = typ

            else:
                # Nested lists.
                if typ is PyDataType.LIST:
                    nested_lvl += 1
                    typ = PyListGenerator(elem, nested_lvl=nested_lvl)

                data_list.append(typ)

            self.parsed_types.append(typ)

        if is_root:

            # We want to start off by adding the nested `dataclass` field
            # first, so it shows up at the top of the container `dataclass`.
            data_dict = {self.name: self.model} if self.model else {}

            data_dict.update({
                f'field_{i + 1}': elem
                for i, elem in enumerate(data_list)
            })

            self.root = PyDataclassGenerator.load_parsed(
                data_dict,
                nested_lvl=nested_lvl
            )
            self.root.name = self.container_name

    def __or__(self, other):
        """Merge two lists together."""
        if not isinstance(other, PyListGenerator):
            raise TypeError(
                f'{self.__class__.__name__}: Incorrect type for `__or__`. '
                f'actual_type: {type(other)}, object={other}')

        # To merge lists with equal number of elements, that's easy enough:
        #   [{"key": "v1"}] | [{"key2": 2}] = [{"key": "v1", "key2": 2}]
        #
        # But... what happens when it's something like this?
        #   [1, {"key": "v1"}] | [{"key2": "2}, "testing", 1, 2, 3]
        #
        # Solution is to merge the model in the other list class with our
        # model -- note that both ours and the other instance end up with only
        # one model after `__post_init__` runs. However, easiest way is to
        # iterate over the nested types in the other list and check for the
        # model explicitly. For the rest of the types in the other list
        # (including nested lists), we just add them to our current list.
        for t in other.parsed_types:
            if isinstance(t, PyDataclassGenerator):
                if self.model:
                    self.model |= t
                    continue
                self.model = t
            self.parsed_types.append(t)

        return self

    def get_lines(self) -> List[str]:

        lines = []

        if self.root:
            lines.append(repr(self.root))

        else:
            if self.model:
                lines.append(repr(self.model))

            for t in self.parsed_types:
                if isinstance(t, PyListGenerator):
                    code = repr(t)
                    if code:
                        # Only if our list already has a dataclass, append
                        # a newline. This should add the proper number of
                        # spaces, in a case like below.
                        #   [{"another_Key":  "value"}, [{"key":  "value"}]]
                        if self.model:
                            lines.append('\n')
                        lines.append(code)

        return lines

    def __str__(self):
        ...

    def _default_str(self):

        if len(self.parsed_types) == 0:
            # We could also wrap it with 'Optional' here, since we see it's
            # an empty list, but it's probably better to not not do that, as
            # 'Optional' generally means the value can be an explicit "null".
            #
            # return ModuleImporter.wrap_string_with_import('list', Optional)
            return ModuleImporter.wrap_string_with_import('', List)

        return ModuleImporter.wrap_string_with_import(
            str(self.parsed_types), List)

    def _experimental_features_str(self):

        if len(self.parsed_types) == 0:
            return 'list'

        return ModuleImporter.wrap_string_with_import(
            str(self.parsed_types), list)

    def __repr__(self):
        """
        Returns the Python `dataclasses` representation of the object.
        """
        return '\n'.join(self.get_lines())


if __name__ == '__main__':
    loader = PyCodeGenerator('../../tests/testdata/test1.json')
    print(loader.py_code)


# Copyright (c) 2006 Bermi Ferrer Martinez
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software to deal in this software without restriction, including
# without limitation the rights to use, copy, modify, merge, publish,
# distribute, sublicense, and/or sell copies of this software, and to permit
# persons to whom this software is furnished to do so, subject to the following
# condition:
#
# THIS SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THIS SOFTWARE OR THE USE OR OTHER DEALINGS IN
# THIS SOFTWARE.