# Copyright 2020 The HuggingFace Team. All rights reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

import argparse
import unittest
from argparse import Namespace
from dataclasses import dataclass, field
from enum import Enum
from typing import List, Optional

from transformers import HfArgumentParser, TrainingArguments


def list_field(default=None, metadata=None):
    return field(default_factory=lambda: default, metadata=metadata)


@dataclass
class BasicExample:
    foo: int
    bar: float
    baz: str
    flag: bool


@dataclass
class WithDefaultExample:
    foo: int = 42
    baz: str = field(default="toto", metadata={"help": "help message"})


@dataclass
class WithDefaultBoolExample:
    foo: bool = False
    baz: bool = True


class BasicEnum(Enum):
    titi = "titi"
    toto = "toto"


@dataclass
class EnumExample:
    foo: BasicEnum = BasicEnum.toto


@dataclass
class OptionalExample:
    foo: Optional[int] = None
    bar: Optional[float] = field(default=None, metadata={"help": "help message"})
    baz: Optional[str] = None
    ces: Optional[List[str]] = list_field(default=[])
    des: Optional[List[int]] = list_field(default=[])


@dataclass
class ListExample:
    foo_int: List[int] = list_field(default=[])
    bar_int: List[int] = list_field(default=[1, 2, 3])
    foo_str: List[str] = list_field(default=["Hallo", "Bonjour", "Hello"])
    foo_float: List[float] = list_field(default=[0.1, 0.2, 0.3])


class HfArgumentParserTest(unittest.TestCase):
    def argparsersEqual(self, a: argparse.ArgumentParser, b: argparse.ArgumentParser) -> bool:
        """
        Small helper to check pseudo-equality of parsed arguments on `ArgumentParser` instances.
        """
        self.assertEqual(len(a._actions), len(b._actions))
        for x, y in zip(a._actions, b._actions):
            xx = {k: v for k, v in vars(x).items() if k != "container"}
            yy = {k: v for k, v in vars(y).items() if k != "container"}
            self.assertEqual(xx, yy)

    def test_basic(self):
        parser = HfArgumentParser(BasicExample)

        expected = argparse.ArgumentParser()
        expected.add_argument("--foo", type=int, required=True)
        expected.add_argument("--bar", type=float, required=True)
        expected.add_argument("--baz", type=str, required=True)
        expected.add_argument("--flag", action="store_true")
        self.argparsersEqual(parser, expected)

    def test_with_default(self):
        parser = HfArgumentParser(WithDefaultExample)

        expected = argparse.ArgumentParser()
        expected.add_argument("--foo", default=42, type=int)
        expected.add_argument("--baz", default="toto", type=str, help="help message")
        self.argparsersEqual(parser, expected)

    def test_with_default_bool(self):
        parser = HfArgumentParser(WithDefaultBoolExample)

        expected = argparse.ArgumentParser()
        expected.add_argument("--foo", action="store_true")
        expected.add_argument("--no_baz", action="store_false", dest="baz")
        self.argparsersEqual(parser, expected)

        args = parser.parse_args([])
        self.assertEqual(args, Namespace(foo=False, baz=True))

        args = parser.parse_args(["--foo", "--no_baz"])
        self.assertEqual(args, Namespace(foo=True, baz=False))

    def test_with_enum(self):
        parser = HfArgumentParser(EnumExample)

        expected = argparse.ArgumentParser()
        expected.add_argument("--foo", default=BasicEnum.toto, choices=list(BasicEnum), type=BasicEnum)
        self.argparsersEqual(parser, expected)

        args = parser.parse_args([])
        self.assertEqual(args.foo, BasicEnum.toto)

        args = parser.parse_args(["--foo", "titi"])
        self.assertEqual(args.foo, BasicEnum.titi)

    def test_with_list(self):
        parser = HfArgumentParser(ListExample)

        expected = argparse.ArgumentParser()
        expected.add_argument("--foo_int", nargs="+", default=[], type=int)
        expected.add_argument("--bar_int", nargs="+", default=[1, 2, 3], type=int)
        expected.add_argument("--foo_str", nargs="+", default=["Hallo", "Bonjour", "Hello"], type=str)
        expected.add_argument("--foo_float", nargs="+", default=[0.1, 0.2, 0.3], type=float)

        self.argparsersEqual(parser, expected)

        args = parser.parse_args([])
        self.assertEqual(
            args,
            Namespace(foo_int=[], bar_int=[1, 2, 3], foo_str=["Hallo", "Bonjour", "Hello"], foo_float=[0.1, 0.2, 0.3]),
        )

        args = parser.parse_args("--foo_int 1 --bar_int 2 3 --foo_str a b c --foo_float 0.1 0.7".split())
        self.assertEqual(args, Namespace(foo_int=[1], bar_int=[2, 3], foo_str=["a", "b", "c"], foo_float=[0.1, 0.7]))

    def test_with_optional(self):
        parser = HfArgumentParser(OptionalExample)

        expected = argparse.ArgumentParser()
        expected.add_argument("--foo", default=None, type=int)
        expected.add_argument("--bar", default=None, type=float, help="help message")
        expected.add_argument("--baz", default=None, type=str)
        expected.add_argument("--ces", nargs="+", default=[], type=str)
        expected.add_argument("--des", nargs="+", default=[], type=int)
        self.argparsersEqual(parser, expected)

        args = parser.parse_args([])
        self.assertEqual(args, Namespace(foo=None, bar=None, baz=None, ces=[], des=[]))

        args = parser.parse_args("--foo 12 --bar 3.14 --baz 42 --ces a b c --des 1 2 3".split())
        self.assertEqual(args, Namespace(foo=12, bar=3.14, baz="42", ces=["a", "b", "c"], des=[1, 2, 3]))

    def test_parse_dict(self):
        parser = HfArgumentParser(BasicExample)

        args_dict = {
            "foo": 12,
            "bar": 3.14,
            "baz": "42",
            "flag": True,
        }

        parsed_args = parser.parse_dict(args_dict)[0]
        args = BasicExample(**args_dict)
        self.assertEqual(parsed_args, args)

    def test_integration_training_args(self):
        parser = HfArgumentParser(TrainingArguments)
        self.assertIsNotNone(parser)
