from dataclasses import dataclass
from enum import Enum
from typing import Dict, Union


class QuorumKind(Enum):
    """QuorumKind defines the kind of quorum.

    Kinds:
        - NONE      - there ain't no quorum
        - ABSOLUTE  - absolute number of minimum voters is required
        - PERCENT   - minimum percentage of valid voters must have voted
    """
    NONE = 0
    ABSOLUTE = 1
    PERCENT = 2


@dataclass
class Quorum:
    """Quorm defines the required quorum of a Voting.
    
    Absolute quorums must be greater than 0.
    Percent quorums must be greather than 0.0 and less then or equal to 100.0.
    """

    kind: QuorumKind
    value: Union[int, float]

    def __init__(self, kind: QuorumKind = None, value: Union[float, int, None] = None):
        super(Quorum)
        if kind is None:
            self.kind = QuorumKind.NONE
        elif isinstance(kind, str):
            self.kind = QuorumKind[kind]
        else:
            self.kind = kind

        if self.kind == QuorumKind.NONE:
            self.value = 0
        elif self.kind == QuorumKind.ABSOLUTE:
            self.value = int(value)
            if self.value <= 0:
                raise ValueError(f"Value can not be less than or equal to zero: {self.value}")
        elif self.kind == QuorumKind.PERCENT:
            self.value = float(value)
            if self.value <= 0.0 or self.value > 100.0:
                raise ValueError(f"Value must be greater than 0.0 and less then or equal to 100.0: {self.value}")

    def as_dict(self) -> Dict:
        return {
            "kind": self.kind.name,
            "value": self.value,
        }