# Copyright 2021 Zilliz. 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 logging
import numpy
from typing import Union, List
from pathlib import Path

import torch
from sentence_transformers import SentenceTransformer

from towhee.operator import NNOperator
# from towhee.dc2 import accelerate

import os
import warnings

warnings.filterwarnings('ignore')
logging.getLogger('sentence_transformers').setLevel(logging.ERROR)
log = logging.getLogger('op_sbert')


class STransformers(NNOperator):
    """
    Operator using pretrained Sentence Transformers
    """

    def __init__(self, model_name: str = None, device: str = None):
        self.model_name = model_name
        if device:
            self.device = device
        else:
            self.device = 'cuda' if torch.cuda.is_available() else 'cpu'
        if self.model_name:
            self.model = SentenceTransformer(model_name_or_path=self.model_name, device=self.device)
        else:
            log.warning('The operator is initialized without specified model.')
            pass

    def __call__(self, txt: Union[List[str], str]):
        if isinstance(txt, str):
            sentences = [txt]
        else:
            sentences = txt
        embs = self.model.encode(sentences)  # return numpy.ndarray
        if isinstance(txt, str):
            embs = embs.squeeze(0)
        else:
            embs = list(embs)
        return embs

    @staticmethod
    def supported_model_names(format: str = None):
        import requests
        req = requests.get("https://www.sbert.net/_static/html/models_en_sentence_embeddings.html")
        data = req.text
        full_list = []
        for line in data.split('\r\n'):
            line = line.replace(' ', '')
            if line.startswith('"name":'):
                name = line.split(':')[-1].replace('"', '').replace(',', '')
                full_list.append(name)
        full_list.sort()
        if format is None:
            model_list = full_list
        elif format == 'pytorch':
            to_remove = []
            assert set(to_remove).issubset(set(full_list))
            model_list = list(set(full_list) - set(to_remove))
        else:
            raise ValueError(f'Invalid or unsupported format "{format}".')
            log.error(f'Invalid or unsupported format "{format}".')
        return model_list