# Copyright (c) 2022 PaddlePaddle Authors. 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 io
import os
from typing import List
from typing import Optional
from typing import Union

import librosa
import paddle
import soundfile

from paddlespeech.cli.asr.infer import ASRExecutor
from paddlespeech.cli.log import logger
from paddlespeech.s2t.frontend.featurizer.text_featurizer import TextFeaturizer
from paddlespeech.s2t.transform.transformation import Transformation
from paddlespeech.s2t.utils.dynamic_import import dynamic_import
from paddlespeech.s2t.utils.utility import UpdateConfig
from paddlespeech.server.engine.base_engine import BaseEngine
from paddlespeech.server.utils.config import get_config

__all__ = ['ASREngine']


class ASRServerExecutor(ASRExecutor):
    def __init__(self):
        super().__init__()
        pass


class ASREngine(BaseEngine):
    """ASR server engine

    Args:
        metaclass: Defaults to Singleton.
    """

    def __init__(self):
        super(ASREngine, self).__init__()

    def init(self, config_file: str) -> bool:
        """init engine resource

        Args:
            config_file (str): config file

        Returns:
            bool: init failed or success
        """
        self.input = None
        self.output = None
        self.executor = ASRServerExecutor()

        self.config = get_config(config_file)
        paddle.set_device(paddle.get_device())
        self.executor._init_from_path(
            self.config.model, self.config.lang, self.config.sample_rate,
            self.config.cfg_path, self.config.decode_method,
            self.config.ckpt_path)

        logger.info("Initialize ASR server engine successfully.")
        return True

    def run(self, audio_data):
        """engine run 

        Args:
            audio_data (bytes): base64.b64decode
        """
        if self.executor._check(
                io.BytesIO(audio_data), self.config.sample_rate,
                self.config.force_yes):
            logger.info("start run asr engine")
            self.executor.preprocess(self.config.model, io.BytesIO(audio_data))
            self.executor.infer(self.config.model)
            self.output = self.executor.postprocess()  # Retrieve result of asr.
        else:
            logger.info("file check failed!")
            self.output = None

    def postprocess(self):
        """postprocess
        """
        return self.output
