import argparse
import os
from logging import Logger
from pathlib import Path
from typing import Dict, List, Optional, TextIO, Tuple

import pandas as pd
from attr import Factory, define, field

from distributed_downloader.tools.checkpoint import Checkpoint
from distributed_downloader.tools.config import Config
from distributed_downloader.tools.registry import ToolsRegistryBase
from distributed_downloader.tools.utils import (
    ensure_created,
    init_logger,
    preprocess_dep_ids,
    submit_job,
    truncate_paths,
)


@define
class Tools:
    config: Config
    tool_name: str

    logger: Logger = field(default=Factory(lambda: init_logger(__name__)))

    tool_folder: Optional[str] = None
    tool_job_history_path: Optional[str] = None
    tool_checkpoint_path: Optional[str] = None
    checkpoint_scheme = {
        "filtering_scheduled": False,
        "filtering_completed": False,
        "scheduling_scheduled": False,
        "scheduling_completed": False,
        "completed": False,
    }

    tool_checkpoint: Optional[Checkpoint] = None
    _checkpoint_override: Optional[Dict[str, bool]] = None
    tool_job_history: Optional[List[int]] = None
    tool_job_history_io: Optional[TextIO] = None

    @classmethod
    def from_path(
        cls,
        path: str,
        tool_name: str,
        checkpoint_override: Optional[Dict[str, bool]] = None,
        tool_name_override: Optional[bool] = False,
    ) -> "Tools":
        if (
            not tool_name_override
            and tool_name not in ToolsRegistryBase.TOOLS_REGISTRY.keys()
        ):
            raise ValueError("unknown tool name")

        return cls(
            config=Config.from_path(path, "tools"),
            tool_name=tool_name,
            checkpoint_override=checkpoint_override,
        )

    def __attrs_post_init__(self):
        # noinspection PyTypeChecker
        self.tool_folder: str = os.path.join(
            self.config.get_folder("tools_folder"), self.tool_name
        )
        self.tool_job_history_path: str = os.path.join(
            self.tool_folder, "job_history.csv"
        )
        self.tool_checkpoint_path: str = os.path.join(
            self.tool_folder, "tool_checkpoint.yaml"
        )

        self.__init_environment()
        self.__init_file_structure()

    def __init_environment(self) -> None:
        os.environ["CONFIG_PATH"] = self.config.config_path
        os.environ["DISTRIBUTED_DOWNLOADER_PATH"] = str(Path(__file__).parent.parent.resolve())

        os.environ["ACCOUNT"] = self.config["account"]
        os.environ["PATH_TO_INPUT"] = self.config["path_to_input"]

        os.environ["PATH_TO_OUTPUT"] = self.config["path_to_output_folder"]
        for output_folder, output_path in self.config.folder_structure.items():
            os.environ["OUTPUT_" + output_folder.upper()] = output_path
        os.environ["OUTPUT_TOOLS_LOGS_FOLDER"] = os.path.join(self.tool_folder, "logs")

        for downloader_var, downloader_value in self.config["tools_parameters"].items():
            os.environ["TOOLS_" + downloader_var.upper()] = str(downloader_value)

        self.logger.info("Environment initialized")

    def __init_file_structure(self):
        ensure_created(
            [
                self.tool_folder,
                os.path.join(self.tool_folder, "filter_table"),
                os.path.join(self.tool_folder, "verification"),
                os.path.join(self.tool_folder, "logs"),
            ]
        )

        self.tool_checkpoint = Checkpoint.from_path(
            self.tool_checkpoint_path, self.checkpoint_scheme
        )
        if self._checkpoint_override is not None:
            for key, value in self._checkpoint_override.items():
                if key == "verification":
                    truncate_paths([os.path.join(self.tool_folder, "verification")])
                    self.tool_checkpoint["completed"] = False
                    continue
                if key not in self.checkpoint_scheme.keys():
                    raise KeyError("Unknown key for override in checkpoint")

                self.tool_checkpoint[key] = value

        self.tool_job_history, self.tool_job_history_io = self.__load_job_history()

    def __load_job_history(self) -> Tuple[List[int], TextIO]:
        job_ids = []

        if os.path.exists(self.tool_job_history_path):
            df = pd.read_csv(self.tool_job_history_path)
            job_ids = df["job_ids"].to_list()
        else:
            with open(self.tool_job_history_path, "w") as f:
                print("job_ids", file=f)

        job_io = open(self.tool_job_history_path, "a")

        return job_ids, job_io

    def __update_job_history(self, new_id: int) -> None:
        self.tool_job_history.append(new_id)
        print(new_id, file=self.tool_job_history_io)

    def __schedule_filtering(self) -> None:
        self.logger.info("Scheduling filtering script")
        job_id = submit_job(
            self.config.get_script("tools_submitter"),
            self.config.get_script("tools_filter_script"),
            self.tool_name,
            *preprocess_dep_ids(
                [self.tool_job_history[-1] if len(self.tool_job_history) != 0 else None]
            ),
            "--spark",
        )
        self.__update_job_history(job_id)
        self.tool_checkpoint["filtered"] = True
        self.logger.info("Scheduled filtering script")

    def __schedule_schedule_creation(self) -> None:
        self.logger.info("Scheduling schedule creation script")
        job_id = submit_job(
            self.config.get_script("tools_submitter"),
            self.config.get_script("tools_scheduling_script"),
            self.tool_name,
            *preprocess_dep_ids([self.tool_job_history[-1]]),
        )
        self.__update_job_history(job_id)
        self.tool_checkpoint["schedule_created"] = True
        self.logger.info("Scheduled schedule creation script")

    def __schedule_workers(self) -> None:
        self.logger.info("Scheduling workers script")

        for _ in range(self.config["tools_parameters"]["num_workers"]):
            job_id = submit_job(
                self.config.get_script("tools_submitter"),
                self.config.get_script("tools_worker_script"),
                self.tool_name,
                *preprocess_dep_ids([self.tool_job_history[-1]]),
            )
            self.__update_job_history(job_id)

        job_id = submit_job(
            self.config.get_script("tools_submitter"),
            self.config.get_script("tools_verification_script"),
            self.tool_name,
            *preprocess_dep_ids([self.tool_job_history[-1]]),
        )
        self.__update_job_history(job_id)

        self.logger.info("Scheduled workers script")

    def apply_tool(self):
        if not (
            self.tool_checkpoint.get("filtering_scheduled", False)
            or self.tool_checkpoint.get("filtering_completed", False)
        ):
            self.__schedule_filtering()
        else:
            self.logger.info(
                "Skipping filtering script: job is already scheduled or table has been already created"
            )

        if not (
            self.tool_checkpoint.get("schedule_scheduled", False)
            or self.tool_checkpoint.get("schedule_completed", False)
        ):
            self.__schedule_schedule_creation()
        else:
            self.logger.info(
                "Skipping schedule creation script: job is already scheduled or schedule has been already created"
            )

        if not self.tool_checkpoint.get("completed", False):
            self.__schedule_workers()
        else:
            self.logger.error("Tool completed its job")

    def __del__(self):
        if self.tool_job_history_io is not None:
            self.tool_job_history_io.close()


def main():
    parser = argparse.ArgumentParser(description="Tools")
    parser.add_argument(
        "config_path",
        metavar="config_path",
        type=str,
        help="the name of the tool that is intended to be used",
    )
    parser.add_argument(
        "tool_name",
        metavar="tool_name",
        type=str,
        help="the name of the tool that is intended to be used",
    )
    parser.add_argument(
        "--reset_filtering",
        action="store_true",
        help="Will reset filtering and scheduling steps",
    )
    parser.add_argument(
        "--reset_scheduling", action="store_true", help="Will reset scheduling step"
    )
    parser.add_argument(
        "--reset_runners",
        action="store_true",
        help="Will reset runners, making them to start over",
    )
    parser.add_argument(
        "--tool_name_override",
        action="store_true",
        help="Will override tool name check (allows for custom tool run)",
    )
    _args = parser.parse_args()

    config_path = _args.config_path
    tool_name = _args.tool_name
    state_override = None
    if _args.reset_filtering:
        state_override = {
            "filtering_scheduled": False,
            "filtering_completed": False,
            "scheduling_scheduled": False,
            "scheduling_completed": False,
            "verification": False,
            "completed": False,
        }
    elif _args.reset_scheduling:
        state_override = {
            "scheduling_scheduled": False,
            "scheduling_completed": False,
            "completed": False,
        }
    if _args.reset_runners:
        state_override = {"verification": False, "completed": False}

    dd = Tools.from_path(
        config_path, tool_name, state_override, _args.tool_name_override
    )
    dd.apply_tool()


if __name__ == "__main__":
    main()
