Source code for webtraversallibrary.color

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#   http://www.apache.org/licenses/LICENSE-2.0

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"""Representation of an RGB(A) color."""

from __future__ import annotations

from dataclasses import dataclass
from typing import Tuple


@dataclass(order=True)
class Color:
    """Representation of an 8-bit RGBA color."""

    r: int
    g: int
    b: int
    a: int = 255

    def __post_init__(self):
        assert all(0 <= channel <= 255 for channel in (self.r, self.g, self.b, self.a))

    @staticmethod
    def from_str(color: str) -> Color:
        """Creates a color from a "#RRGGBBAA" representation. Alpha is optional."""
        if color.startswith("#"):
            color = color[1:]
        r = int(color[0:2], 16)
        g = int(color[2:4], 16)
        b = int(color[4:6], 16)
        a = int(color[6:], 16) if len(color) == 8 else 255
        return Color(r, g, b, a)

    def to_str(self, with_alpha: bool = False) -> str:
        """Creates an "#RRGGBBAA" string from this color. Alpha is optional."""

        def _hex(n):
            return hex(n)[2:].zfill(2)

        color = f"#{_hex(self.r)}{_hex(self.g)}{_hex(self.b)}"
        if with_alpha:
            color += f"{hex(self.a)[2:]}"
        return color.upper()

    def to_tuple(self, with_alpha: bool = False) -> Tuple:
        """
        Returns either a 3- or a 4-tuple with the values,
        depending on the value of `with_alpha`.
        """
        if with_alpha:
            return (self.r, self.g, self.b, self.a)
        return (self.r, self.g, self.b)