from dataclasses import dataclass
from operator import itemgetter
from typing import Tuple, Dict, List

from cache.Cache import Cache
from core.sheerka.services.sheerka_service import BaseService, ServiceObj


@dataclass
class FunctionParametersObj(ServiceObj):
    name: str
    params: Dict[int, List[Tuple[str, int]]]
    #
    # params = {
    #    1 : [('value 1', 1), ('value 2', 5)],
    #    3 : [('value 3', 5)]
    #
    # the key is the number of the parameter
    # the values are a tuple of (value seen, number of time this value is seen)


class SheerkaFunctionsParametersHistory(BaseService):
    """
    This service remembers the parameters expected by functions
    """

    NAME = "FunctionsParametersHistory"
    FUNCTIONS_PARAMETERS_ENTRY = "FunctionsParametersHistory:Functions"

    def __init__(self, sheerka):
        super().__init__(sheerka)
        self.cache = Cache(max_size=1024, default=lambda k: self.sheerka.sdp.get(self.FUNCTIONS_PARAMETERS_ENTRY, k))

    def initialize(self):
        self.sheerka.cache_manager.register_cache(self.FUNCTIONS_PARAMETERS_ENTRY, self.cache, True, True)
        return self

    def record_function_parameter(self, context, func_name: str, param_number: int, param_value: str):
        """
        Declare a new value to the parameter and function
        :param context:
        :param func_name:
        :param param_number:
        :param param_value:
        :return:
        """
        old = self.cache.get(func_name)
        if old is not None:
            if param_number in old.params:
                lst = old.params[param_number]
                for i, value in enumerate(lst):  # value is a tuple (param_value, counter)
                    if value[0] == param_value:
                        lst[i] = (param_value, value[1] + 1)
                        break
                else:
                    lst.append((param_value, 1))
            else:
                old.params[param_number] = [(param_value, 1)]
            self.cache.put(func_name, old)
        else:
            obj = FunctionParametersObj(context.event.get_digest(), func_name, {param_number: [(param_value, 1)]})
            self.cache.put(func_name, obj)

    def get_function_parameters(self, func_name: str, param_number: int):
        """
        Return the list of param
        :param func_name:
        :param param_number:
        :return:
        """
        values = self.cache.get(func_name)
        if values is None:
            return []

        if param_number not in values.params:
            return []

        return [item[0] for item in sorted(values.params[param_number], key=itemgetter(1), reverse=True)]