[WIP] feat: Add utils for table printing.

.gitignore

@@ -1,6 +1,7 @@
 # Singletons
 .env
 /__init__.py
+.table.png
 
 # IDE config folders
 .idea

requirements.txt

@@ -1,4 +1,6 @@
 bottle==0.12.19
+Pillow~=9.0.1
 python-dotenv==0.19.2
 slackclient==2.9.3
 sentry-sdk[bottle]==0.16.2
+tabulate~=0.8.9

slack_bot/messenger.py

@@ -59,7 +59,6 @@ def compose_message(event: GitHubEvent) -> tuple[str, str | None]:
         message: str = ""
         details: str | None = None
 
-        # TODO: Beautify messages.
         if event.type == EventType.BRANCH_CREATED:
             message = f"Branch created by {event.user}: `{event.ref}`"
         elif event.type == EventType.BRANCH_DELETED:

utils/table.py

@@ -0,0 +1,107 @@
+"""
+Contains the `Table` class, to convert an iterable into an image of a table.
+"""
+
+from math import ceil
+
+from PIL import ImageFont, Image, ImageDraw, ImageChops
+from tabulate import tabulate
+
+MARGIN_PIXELS = 2
+IMAGE_PATH = "../.table.png"
+
+
+class Table:
+    """
+    Wrapper for a single method (`iter_to_image`), for consistency's sake only.
+    """
+
+    @staticmethod
+    def data_to_image(headers: list[str], rows: list[list[str]]):
+        """
+        Converts the passed iterable into an image of a table and saves it in the `.table` file.
+        """
+        lines = Table._data_to_table(headers, rows)
+        Table._table_to_image(lines)
+
+    @staticmethod
+    def _data_to_table(headers: list[str], rows: list[list[str]]) -> list[str]:
+        """
+        Uses the `tabulate` package to create a table using ASCII characters.
+        :param headers: List of headers of the table.
+        :param rows: Row-wise data in the table.
+        :return: ASCII table as a list of lines.
+        """
+        table_string = tabulate(
+            rows,
+            headers=headers,
+            tablefmt="grid",
+        )
+        return table_string.splitlines()
+
+    @staticmethod
+    def _table_to_image(lines: list[str]) -> None:
+        """
+        Draws the passed ASCII table using `Pillow` and save to `IMAGE_PATH`.
+        :param lines: ASCII table as a list of lines.
+        """
+        font = ImageFont.truetype(font="font-style.ttf", size=40)
+
+        image, draw, max_line_height = Table._draw_background(lines, font)
+        Table._draw_text(draw, lines, font, max_line_height)
+        Table._save(image)
+
+    @staticmethod
+    def _draw_background(
+            lines: list[str],
+            font: ImageFont,
+    ) -> tuple[Image, ImageDraw, int]:
+        # Calculate dimensions
+        tallest_line = max(lines, key=lambda line: font.getsize(line)[1])
+        widest_line = max(lines, key=lambda line: font.getsize(line)[0])
+        max_line_height, max_line_width = (
+            Table._fpt_to_px(font.getsize(tallest_line)[1]),
+            Table._fpt_to_px(font.getsize(widest_line)[0]),
+        )
+        image_height = ceil(max_line_height * 0.8 * len(lines) + 2 * MARGIN_PIXELS)
+        image_width = ceil(max_line_width + 2 * MARGIN_PIXELS)
+
+        # Draw the background
+        background_color = 255
+        image = Image.new("L", (image_width, image_height), color=background_color)
+        draw = ImageDraw.Draw(image)
+
+        return image, draw, max_line_height
+
+    @staticmethod
+    def _draw_text(
+            draw: ImageDraw,
+            lines: list[str],
+            font: ImageFont,
+            max_line_height: int,
+    ):
+        for i, line in enumerate(lines):
+            draw.text(
+                (MARGIN_PIXELS, round(MARGIN_PIXELS + i * max_line_height * 0.8)),
+                line,
+                fill=0,
+                font=font,
+            )
+
+    @staticmethod
+    def _fpt_to_px(points: int) -> int:
+        """
+        Converts font points to pixels
+        :param points: Font points value
+        :return: Pixels value
+        """
+        return round(points * 96 / 72)
+
+    @staticmethod
+    def _save(image: Image):
+        background = image.getpixel((0, 0))
+        border = Image.new("L", image.size, background)
+        diff = ImageChops.difference(image, border)
+        bbox = diff.getbbox()
+        image = image.crop(bbox) if bbox else image
+        image.save(IMAGE_PATH)