# Copyright (c) 2021 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.
"""Server-end for the ASR demo."""
import functools

import numpy as np
import paddle
from paddle.io import DataLoader
from yacs.config import CfgNode

from paddlespeech.s2t.io.collator import SpeechCollator
from paddlespeech.s2t.io.dataset import ManifestDataset
from paddlespeech.s2t.models.ds2 import DeepSpeech2Model
from paddlespeech.s2t.training.cli import default_argument_parser
from paddlespeech.s2t.utils.socket_server import AsrRequestHandler
from paddlespeech.s2t.utils.socket_server import AsrTCPServer
from paddlespeech.s2t.utils.socket_server import warm_up_test
from paddlespeech.utils.argparse import add_arguments
from paddlespeech.utils.argparse import print_arguments


def start_server(config, args):
    """Start the ASR server"""
    config.defrost()
    config.manifest = config.test_manifest
    dataset = ManifestDataset.from_config(config)

    config.augmentation_config = ""
    config.keep_transcription_text = True
    config.batch_size = 1
    config.num_workers = 0
    collate_fn = SpeechCollator.from_config(config)
    test_loader = DataLoader(dataset, collate_fn=collate_fn, num_workers=0)

    model = DeepSpeech2Model.from_pretrained(test_loader, config,
                                             args.checkpoint_path)
    model.eval()

    # prepare ASR inference handler
    def file_to_transcript(filename):
        feature = test_loader.collate_fn.process_utterance(filename, "")
        audio = np.array([feature[0]]).astype('float32')  #[1, T, D]
        # audio = audio.swapaxes(1,2)
        print('---file_to_transcript feature----')
        print(audio.shape)
        audio_len = feature[0].shape[0]
        print(audio_len)
        audio_len = np.array([audio_len]).astype('int64')  # [1]

        result_transcript = model.decode(
            paddle.to_tensor(audio),
            paddle.to_tensor(audio_len),
            vocab_list=test_loader.collate_fn.vocab_list,
            decoding_method=config.decode.decoding_method,
            lang_model_path=config.decode.lang_model_path,
            beam_alpha=config.decode.alpha,
            beam_beta=config.decode.beta,
            beam_size=config.decode.beam_size,
            cutoff_prob=config.decode.cutoff_prob,
            cutoff_top_n=config.decode.cutoff_top_n,
            num_processes=config.decode.num_proc_bsearch)
        return result_transcript[0]

    # warming up with utterrances sampled from Librispeech
    print('-----------------------------------------------------------')
    print('Warming up ...')
    warm_up_test(
        audio_process_handler=file_to_transcript,
        manifest_path=args.warmup_manifest,
        num_test_cases=3)
    print('-----------------------------------------------------------')

    # start the server
    server = AsrTCPServer(
        server_address=(args.host_ip, args.host_port),
        RequestHandlerClass=AsrRequestHandler,
        speech_save_dir=args.speech_save_dir,
        audio_process_handler=file_to_transcript)
    print("ASR Server Started.")
    server.serve_forever()


def main(config, args):
    start_server(config, args)


if __name__ == "__main__":
    parser = default_argument_parser()
    add_arg = functools.partial(add_arguments, argparser=parser)
    # yapf: disable
    add_arg('host_ip',          str,
            'localhost',
            "Server's IP address.")
    add_arg('host_port',        int,    8088,    "Server's IP port.")
    add_arg('speech_save_dir',  str,
            'demo_cache',
            "Directory to save demo audios.")
    add_arg('warmup_manifest', str, None, "Filepath of manifest to warm up.")
    args = parser.parse_args()
    print_arguments(args, globals())

    # https://yaml.org/type/float.html
    config = CfgNode(new_allowed=True)
    if args.config:
        config.merge_from_file(args.config)
    if args.decode_cfg:
        decode_confs = CfgNode(new_allowed=True)
        decode_confs.merge_from_file(args.decode_cfg)
        config.decode = decode_confs
    if args.opts:
        config.merge_from_list(args.opts)
    config.freeze()
    print(config)

    args.warmup_manifest = config.test_manifest
    print_arguments(args, globals())

    if args.dump_config:
        with open(args.dump_config, 'w') as f:
            print(config, file=f)

    main(config, args)
