# Copyright 2025 the LlamaFactory team.
#
# 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.
from functools import lru_cache

import torch


def get_available_accelerator():
    """Get available accelerator in current environment.

    Note: this api requires torch>=2.7.0, 2.6 or lower will get an AttributeError or RuntimeError
    """
    accelerator = torch.accelerator.current_accelerator()
    if accelerator is None:
        return torch.device('cpu')
    return accelerator


@lru_cache
def is_torch_npu_available():
    return get_available_accelerator().type == 'npu'


@lru_cache
def is_torch_cuda_available():
    return get_available_accelerator().type == 'cuda'


@lru_cache
def is_torch_xpu_available():
    return get_available_accelerator().type == 'xpu'


@lru_cache
def is_torch_mps_available():
    return get_available_accelerator().type == 'mps'