Source code for webtraversallibrary.graphics

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"""
Module containing helper functions for graphics-related operations on webdrivers and snapshots.
"""

import importlib.resources
import logging

from PIL import Image, ImageDraw, ImageFont

from .color import Color
from .geometry import Point, Rectangle

logger = logging.getLogger("wtl")


def crop_image(image: Image.Image, rect: Rectangle) -> Image.Image:
    """
    Crops the part of the image specified by its ``rect``.

    Rectangle specified by ``rect`` must lie inside of the image bounds.
    """

    if rect.area == 0:
        raise ValueError(f"Rectangle {rect} is degenerate")

    # Rectangle we crop out must be somewhere within the image
    image_rect = Rectangle(Point(0, 0), Point(image.width, image.height))
    if rect not in image_rect:
        raise ValueError(f"Bounds {rect} outside of image area {image_rect}")

    return image.crop(rect.bounds)


def draw_rect(image: Image.Image, rect: Rectangle, color: Color, width: int):
    """
    Draws a bounding box around the specified rectangle on the image.
    """
    draw = ImageDraw.Draw(image, mode="RGBA")
    draw.rectangle(rect.bounds, outline=color.to_tuple(with_alpha=True), width=width)


def draw_text(image: Image.Image, top_left: Point, color: Color, size: int, text: str):
    """
    Draws text on a PIL image.
    """
    padding = 2
    image_width, image_height = image.size

    with importlib.resources.path("webtraversallibrary.font", "OpenSans-Regular.ttf") as filepath:
        font = ImageFont.truetype(str(filepath), size)

    # Make sure text does not exceed image boundaries
    text_width, text_height = font.getsize(text)
    draw_text_x = min(top_left.x, image_width - text_width - padding)
    draw_text_y = min(top_left.y, image_height - text_height - padding)
    draw = ImageDraw.Draw(image, mode="RGB")
    draw.text(xy=(draw_text_x, draw_text_y), text=text, fill=color.to_tuple(), font=font)