# copyright (c) 2024 PaddlePaddle Authors. All Rights Reserve.
#
# 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 os
import json
import time
import tarfile
from pathlib import Path
import paddle

from ..base import BaseTrainer, BaseTrainDeamon
from ...utils.config import AttrDict
from .model_list import MODELS


class TSCLSTrainer(BaseTrainer):
    """TS Classification Model Trainer"""

    entities = MODELS

    def build_deamon(self, config: AttrDict) -> "TSCLSTrainDeamon":
        """build deamon thread for saving training outputs timely

        Args:
            config (AttrDict): PaddleX pipeline config, which is loaded from pipeline yaml file.

        Returns:
            TSCLSTrainDeamon: the training deamon thread object for saving training outputs timely.
        """
        return TSCLSTrainDeamon(config)

    def train(self):
        """firstly, update and dump train config, then train model"""
        # XXX: using super().train() instead when the train_hook() is supported.
        os.makedirs(self.global_config.output, exist_ok=True)
        self.update_config()
        self.dump_config()
        train_result = self.pdx_model.train(**self.get_train_kwargs())
        assert (
            train_result.returncode == 0
        ), f"Encountered an unexpected error({train_result.returncode}) in \
training!"

        self.make_tar_file()
        self.deamon.stop()

    def make_tar_file(self):
        """make tar file to package the training outputs"""
        tar_path = Path(self.global_config.output) / "best_accuracy.pdparams.tar"
        with tarfile.open(tar_path, "w") as tar:
            tar.add(self.global_config.output, arcname="best_accuracy.pdparams")

    def update_config(self):
        """update training config"""
        self.pdx_config.update_dataset(self.global_config.dataset_dir, "TSCLSDataset")
        if self.train_config.time_col is not None:
            self.pdx_config.update_basic_info({"time_col": self.train_config.time_col})
        if self.train_config.target_cols is not None:
            self.pdx_config.update_basic_info(
                {"target_cols": self.train_config.target_cols.split(",")}
            )
        if self.train_config.group_id is not None:
            self.pdx_config.update_basic_info({"group_id": self.train_config.group_id})
        if self.train_config.static_cov_cols is not None:
            self.pdx_config.update_basic_info(
                {"static_cov_cols": self.train_config.static_cov_cols}
            )
        if self.train_config.freq is not None:
            try:
                self.train_config.freq = int(self.train_config.freq)
            except ValueError:
                pass
            self.pdx_config.update_basic_info({"freq": self.train_config.freq})
        if self.train_config.batch_size is not None:
            self.pdx_config.update_batch_size(self.train_config.batch_size)
        if self.train_config.learning_rate is not None:
            self.pdx_config.update_learning_rate(self.train_config.learning_rate)
        if self.train_config.epochs_iters is not None:
            self.pdx_config.update_epochs(self.train_config.epochs_iters)
        if self.global_config.output is not None:
            self.pdx_config.update_save_dir(self.global_config.output)

    def get_train_kwargs(self) -> dict:
        """get key-value arguments of model training function

        Returns:
            dict: the arguments of training function.
        """
        train_args = {"device": self.get_device()}
        if self.global_config.output is not None:
            train_args["save_dir"] = self.global_config.output
        return train_args


class TSCLSTrainDeamon(BaseTrainDeamon):
    """TSCLSTrainResultDemon"""

    def get_watched_model(self):
        """get the models needed to be watched"""
        watched_models = []
        watched_models.append("best")
        return watched_models

    def update(self):
        """update train result json"""
        self.processing = True
        for i, result in enumerate(self.results):
            self.results[i] = self.update_result(result, self.train_outputs[i])
        self.save_json()
        self.processing = False

    def update_train_log(self, train_output):
        """update train log"""
        train_log_path = train_output / "train_ct.log"
        with open(train_log_path, "w") as f:
            seconds = time.time()
            f.write(
                "current training time: "
                + time.strftime("%Y-%m-%d %H:%M:%S", time.localtime(seconds))
            )
        f.close()
        return train_log_path

    def update_result(self, result, train_output):
        """update every result"""
        train_output = Path(train_output).resolve()
        config_path = Path(train_output).joinpath("config.yaml").resolve()
        if not config_path.exists():
            return result

        model_name = result["model_name"]
        if (
            model_name in self.config_recorder
            and self.config_recorder[model_name] != config_path
        ):
            result["models"] = self.init_model_pkg()
        result["config"] = config_path
        self.config_recorder[model_name] = config_path

        result["config"] = config_path
        result["train_log"] = self.update_train_log(train_output)
        result["visualdl_log"] = self.update_vdl_log(train_output)
        result["label_dict"] = self.update_label_dict(train_output)
        model = self.get_model(result["model_name"], config_path)
        self.update_models(result, model, train_output, "best")

        return result

    def update_models(self, result, model, train_output, model_key):
        """update info of the models to be saved"""
        pdparams = Path(train_output).joinpath("best_accuracy.pdparams.tar")
        if pdparams.exists():

            score = self.get_score(Path(train_output).joinpath("score.json"))

            result["models"][model_key] = {
                "score": "%.3f" % score,
                "pdparams": pdparams,
                "pdema": "",
                "pdopt": "",
                "pdstates": "",
                "inference_config": "",
                "pdmodel": "",
                "pdiparams": pdparams,
                "pdiparams.info": "",
            }
        self.update_inference_model(
            model,
            train_output,
            train_output.joinpath(f"inference"),
            result["models"][model_key],
        )

    def update_inference_model(
        self, model, weight_path, export_save_dir, result_the_model
    ):
        """update inference model"""
        export_save_dir.mkdir(parents=True, exist_ok=True)
        export_result = model.export(weight_path=weight_path, save_dir=export_save_dir)

        if export_result.returncode == 0:
            inference_config = export_save_dir.joinpath("inference.yml")
            if not inference_config.exists():
                inference_config = ""
            use_pir = (
                hasattr(paddle.framework, "use_pir_api")
                and paddle.framework.use_pir_api()
            )
            pdmodel = (
                export_save_dir.joinpath("inference.json")
                if use_pir
                else export_save_dir.joinpath("inference.pdmodel")
            )
            pdiparams = export_save_dir.joinpath("inference.pdiparams")
            pdiparams_info = (
                "" if use_pir else export_save_dir.joinpath("inference.pdiparams.info")
            )
        else:
            inference_config = ""
            pdmodel = ""
            pdiparams = ""
            pdiparams_info = ""

        result_the_model["inference_config"] = inference_config
        result_the_model["pdmodel"] = pdmodel
        result_the_model["pdiparams"] = pdiparams
        result_the_model["pdiparams.info"] = pdiparams_info

    def get_score(self, score_path):
        """get the score by pdstates file"""
        if not Path(score_path).exists():
            return 0
        return json.load(open(score_path))["metric"]

    def get_best_ckp_prefix(self):
        """get the prefix of the best checkpoint file"""
        pass

    def get_epoch_id_by_pdparams_prefix(self):
        """get the epoch_id by pdparams file"""
        pass

    def get_ith_ckp_prefix(self):
        """get the prefix of the epoch_id checkpoint file"""
        pass

    def get_the_pdema_suffix(self):
        """get the suffix of pdema file"""
        pass

    def get_the_pdopt_suffix(self):
        """get the suffix of pdopt file"""
        pass

    def get_the_pdparams_suffix(self):
        """get the suffix of pdparams file"""
        pass

    def get_the_pdstates_suffix(self):
        """get the suffix of pdstates file"""
        pass