going-rogue/roguebasin/geometry.py

#!/usr/bin/env python3
# Eryn Wells <eryn@erynwells.me>

from dataclasses import dataclass
from typing import Any, Iterator, overload

@dataclass(frozen=True)
class Point:
    x: int = 0
    y: int = 0

    @overload
    def __add__(self, other: 'Vector') -> 'Point':
        ...

    def __add__(self, other: Any) -> 'Point':
        if not isinstance(other, Vector):
            raise TypeError('Only Vector can be added to a Point')
        return Point(self.x + other.dx, self.y + other.dy)

    def __iter__(self):
        yield self.x
        yield self.y

    def __str__(self):
        return f'(x:{self.x}, y:{self.y})'

@dataclass(frozen=True)
class Vector:
    dx: int = 0
    dy: int = 0

    def __iter__(self):
        yield self.dx
        yield self.dy

    def __str__(self):
        return f'(δx:{self.x}, δy:{self.y})'

class Direction:
    North = Vector(0, -1)
    NorthEast = Vector(1, -1)
    East = Vector(1, 0)
    SouthEast = Vector(1, 1)
    South = Vector(0, 1)
    SouthWest = Vector(-1, 1)
    West = Vector(-1, 0)
    NorthWest = Vector(-1, -1)

    @classmethod
    def all(cls) -> Iterator['Direction']:
        yield Direction.North
        yield Direction.NorthEast
        yield Direction.East
        yield Direction.SouthEast
        yield Direction.South
        yield Direction.SouthWest
        yield Direction.West
        yield Direction.NorthWest

@dataclass(frozen=True)
class Size:
    width: int = 0
    height: int = 0

    def __iter__(self):
        yield self.width
        yield self.height

    def __str__(self):
        return f'(w:{self.width}, h:{self.height})'

@dataclass(frozen=True)
class Rect:
    origin: Point
    size: Size

    @property
    def min_x(self) -> int:
        '''Minimum x-value that is still within the bounds of this rectangle. This is the origin's x-value.'''
        return self.origin.x

    @property
    def min_y(self) -> int:
        '''Minimum y-value that is still within the bounds of this rectangle. This is the origin's y-value.'''
        return self.origin.y

    @property
    def mid_x(self) -> int:
        '''The x-value of the center point of this rectangle.'''
        return int(self.origin.x + self.size.width / 2)

    @property
    def mid_y(self) -> int:
        '''The y-value of the center point of this rectangle.'''
        return int(self.origin.y + self.size.height / 2)

    @property
    def max_x(self) -> int:
        '''Maximum x-value that is still within the bounds of this rectangle.'''
        return self.origin.x + self.size.width - 1

    @property
    def max_y(self) -> int:
        '''Maximum y-value that is still within the bounds of this rectangle.'''
        return self.origin.y + self.size.height - 1

    @property
    def midpoint(self) -> Point:
        return Point(self.mid_x, self.mid_y)

    def inset_rect(self, top: int = 0, right: int = 0, bottom: int = 0, left: int = 0) -> 'Rect':
        '''
        Return a new Rect inset from this rect by the specified values. Arguments are listed in clockwise order around
        the permeter. This method doesn't do any validation or transformation of the returned Rect to make sure it's
        valid.
        '''
        return Rect(Point(self.origin.x + left, self.origin.y + top),
                    Size(self.size.width - right - left, self.size.height - top - bottom))

    def __iter__(self):
        yield tuple(self.origin)
        yield tuple(self.size)

    def __str__(self):
        return f'[{self.origin}, {self.size}]'