# Copyright 2021 The HuggingFace Inc. 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 importlib

import os

from collections import OrderedDict

import importlib_metadata

from requests.exceptions import HTTPError

from .logging import get_logger

logger = get_logger(__name__)

hf_cache_home = os.path.expanduser(

os.getenv("HF_HOME", os.path.join(os.getenv("XDG_CACHE_HOME", "~/.cache"), "huggingface"))

)

default_cache_path = os.path.join(hf_cache_home, "diffusers")

CONFIG_NAME = "config.json"

HUGGINGFACE_CO_RESOLVE_ENDPOINT = "https://huggingface.co"

DIFFUSERS_CACHE = default_cache_path

DIFFUSERS_DYNAMIC_MODULE_NAME = "diffusers_modules"

HF_MODULES_CACHE = os.getenv("HF_MODULES_CACHE", os.path.join(hf_cache_home, "modules"))

_transformers_available = importlib.util.find_spec("transformers") is not None

try:

_transformers_version = importlib_metadata.version("transformers")

logger.debug(f"Successfully imported transformers version {_transformers_version}")

except importlib_metadata.PackageNotFoundError:

_transformers_available = False

_inflect_available = importlib.util.find_spec("inflect") is not None

try:

_inflect_version = importlib_metadata.version("inflect")

logger.debug(f"Successfully imported inflect version {_inflect_version}")

except importlib_metadata.PackageNotFoundError:

_inflect_available = False

_unidecode_available = importlib.util.find_spec("unidecode") is not None

try:

_unidecode_version = importlib_metadata.version("unidecode")

logger.debug(f"Successfully imported unidecode version {_unidecode_version}")

except importlib_metadata.PackageNotFoundError:

_unidecode_available = False

def is_transformers_available():

return _transformers_available

def is_inflect_available():

return _inflect_available

def is_unidecode_available():

return _unidecode_available

class RepositoryNotFoundError(HTTPError):

"""

Raised when trying to access a hf.co URL with an invalid repository name, or with a private repo name the user does

not have access to.

"""

class EntryNotFoundError(HTTPError):

"""Raised when trying to access a hf.co URL with a valid repository and revision but an invalid filename."""

class RevisionNotFoundError(HTTPError):

"""Raised when trying to access a hf.co URL with a valid repository but an invalid revision."""

TRANSFORMERS_IMPORT_ERROR = """

{0} requires the transformers library but it was not found in your environment. You can install it with pip: `pip

install transformers`

"""

UNIDECODE_IMPORT_ERROR = """

{0} requires the unidecode library but it was not found in your environment. You can install it with pip: `pip install

Unidecode`

"""

INFLECT_IMPORT_ERROR = """

{0} requires the inflect library but it was not found in your environment. You can install it with pip: `pip install

inflect`

"""

BACKENDS_MAPPING = OrderedDict(

[

("transformers", (is_transformers_available, TRANSFORMERS_IMPORT_ERROR)),

("unidecode", (is_unidecode_available, UNIDECODE_IMPORT_ERROR)),

("inflect", (is_inflect_available, INFLECT_IMPORT_ERROR)),

]

)

def requires_backends(obj, backends):

if not isinstance(backends, (list, tuple)):

backends = [backends]

name = obj.__name__ if hasattr(obj, "__name__") else obj.__class__.__name__

checks = (BACKENDS_MAPPING[backend] for backend in backends)

failed = [msg.format(name) for available, msg in checks if not available()]

if failed:

raise ImportError("".join(failed))

class DummyObject(type):

"""

Metaclass for the dummy objects. Any class inheriting from it will return the ImportError generated by

`requires_backend` each time a user tries to access any method of that class.

"""

def __getattr__(cls, key):

if key.startswith("_"):

return super().__getattr__(cls, key)

requires_backends(cls, cls._backends)