from collections import namedtuple

from core.global_symbols import NotInit
from core.sheerka.services.sheerka_service import BaseService
from sdp.sheerkaDataProvider import Event

hist = namedtuple("HistoryTest", "text status")  # tests purposes only


class History:
    def __init__(self, event: Event, result, extra_info):
        self.event = event
        self.result = result
        self.extra_info = extra_info
        self._status = NotInit
        self._is_state_modified = NotInit
        self._format_instructions = None

    def __str__(self):
        if self.is_state_modified is NotInit:
            state_modified_str = "[?]"
        else:
            state_modified_str = "[X]" if self.is_state_modified else "[ ]"
        event_date = self.event.date.strftime('%d/%m/%Y %H:%M:%S')

        msg = f"{self.event.get_digest()} {event_date} {state_modified_str} : {self.event.message}"
        status = self.status
        if status is not None:
            msg += f" => {status}"
        return msg

    def __repr__(self):
        return f"History(event={self.event!r}, status={self.status}, result={self.result})"

    def __eq__(self, other):
        if id(self) == id(other):
            return True

        if isinstance(other, hist):
            return self.event.message == other.text and self.status == other.status

        if not isinstance(other, History):
            return False

        return self.event == other.event and self.result == other.result

    def __hash__(self):
        return hash((self.event, self.result, self.status))

    @property
    def status(self):
        if self._status is not NotInit:
            return self._status

        if self.extra_info and "status" in self.extra_info:
            self._status = self.extra_info["status"]
            return self._status

        self._status = self.result.get_status() if self.result else None
        return self._status

    @property
    def is_state_modified(self):
        if self._is_state_modified is not NotInit:
            return self._is_state_modified

        if self.extra_info and "is_state_modified" in self.extra_info:
            self._is_state_modified = self.extra_info["is_state_modified"]
            return self._is_state_modified

        self._is_state_modified = self.result.is_state_modified() if self.result else None
        return self._is_state_modified

    def get_format_instructions(self):
        return self._format_instructions

    def set_format_instructions(self, instructions):
        self._format_instructions = instructions


class SheerkaHistoryManager(BaseService):
    NAME = "History"

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

    def history(self, depth=10, start=0):
        """
        Load history
        :param depth: number of items
        :param start:
        :return:
        """

        events = list(self.sheerka.om.current_sdp().load_events(depth, start))
        for event in events:
            try:
                result = self.sheerka.om.current_sdp().load_result(event.get_digest())
            except (IOError, KeyError):
                result = None

            try:
                extra_info = self.sheerka.om.current_sdp().load_result_extra_info(event.get_digest())
            except (IOError, KeyError):
                extra_info = None

            yield History(event, result, extra_info)