from __future__ import annotations
from .coordinate import Coordinate
from typing import Union

OFF_STATES = [False, 0, None]
OFF = False
ON = True


class Grid:
    def __init__(self, default=False):
        self.__default = default
        self.__grid = {}
        self.__minX = 0
        self.__minY = 0
        self.__maxX = 0
        self.__maxY = 0

    def __trackBoundaries(self, pos: Coordinate):
        if pos.x < self.__minX:
            self.__minX = pos.x

        if pos.y < self.__minY:
            self.__minY = pos.y

        if pos.x > self.__maxX:
            self.__maxX = pos.x

        if pos.y > self.__maxY:
            self.__maxY = pos.y

    def toggle(self, pos: Coordinate):
        if pos in self.__grid:
            del self.__grid[pos]
        else:
            self.__trackBoundaries(pos)
            self.__grid[pos] = not self.__default

    def set(self, pos: Coordinate, value: any):
        if value in OFF_STATES and pos in self.__grid:
            del self.__grid[pos]
        elif value not in OFF_STATES:
            self.__trackBoundaries(pos)
            self.__grid[pos] = value

    def getState(self, pos: Coordinate) -> bool:
        if pos not in self.__grid:
            return False
        else:
            return self.__grid[pos] not in OFF_STATES

    def getValue(self, pos: Coordinate) -> any:
        if pos not in self.__grid:
            return self.__default
        else:
            return self.__grid[pos]

    def getOnCount(self):
        return len(self.__grid)

    def isSet(self, pos: Coordinate) -> bool:
        return pos in self.__grid

    def isCorner(self, pos: Coordinate) -> bool:
        return pos in [
            Coordinate(self.__minX, self.__minY),
            Coordinate(self.__minX, self.__maxY),
            Coordinate(self.__maxX, self.__minY),
            Coordinate(self.__maxX, self.__maxY),
        ]

    def add(self, pos: Coordinate, value: Union[float, int] = 1):
        if pos in self.__grid:
            self.__grid[pos] += value
        else:
            self.__trackBoundaries(pos)
            self.__grid[pos] = self.__default + value

    def sub(self, pos: Coordinate, value: Union[float, int] = 1):
        if pos in self.__grid:
            self.__grid[pos] -= value
        else:
            self.__trackBoundaries(pos)
            self.__grid[pos] = self.__default - value

    def getSum(self, includeNegative: bool = True):
        grid_sum = 0
        for value in self.__grid.values():
            if includeNegative or value > 0:
                grid_sum += value

        return grid_sum

    def getNeighbourSum(self, pos: Coordinate, includeNegative: bool = True, includeDiagonal: bool = True) \
            -> Union[float, int]:
        neighbour_sum = 0
        for neighbour in pos.getNeighbours(
                includeDiagonal=includeDiagonal,
                minX=self.__minX, minY=self.__minY,
                maxX=self.__maxX, maxY=self.__maxY):
            if neighbour in self.__grid:
                if includeNegative or self.__grid[neighbour] > 0:
                    neighbour_sum += self.__grid[neighbour]

        return neighbour_sum