Inkycal/inkycal/custom/functions.py

"""
Inkycal custom-functions for ease-of-use

Copyright by aceinnolab
"""
import json
import logging
import os
import time
import traceback

import arrow
import PIL
import requests
import tzlocal
from PIL import Image
from PIL import ImageDraw
from PIL import ImageFont

logs = logging.getLogger(__name__)
logs.setLevel(level=logging.INFO)

# Get the path to the Inkycal folder
top_level = os.path.dirname(os.path.abspath(os.path.dirname(__file__))).split("/inkycal")[0]

# Get path of 'fonts' and 'images' folders within Inkycal folder
fonts_location = os.path.join(top_level, "fonts/")
image_folder = os.path.join(top_level, "image_folder/")

# Get available fonts within fonts folder
fonts = {}

for path, dirs, files in os.walk(fonts_location):
    for _ in files:
        if _.endswith(".otf"):
            name = _.split(".otf")[0]
            fonts[name] = os.path.join(path, _)

        if _.endswith(".ttf"):
            name = _.split(".ttf")[0]
            fonts[name] = os.path.join(path, _)
logs.debug(f"Found fonts: {json.dumps(fonts, indent=4, sort_keys=True)}")
available_fonts = [key for key, values in fonts.items()]


def get_fonts():
    """Print all available fonts by name.

    Searches the /font folder in Inkycal and displays all fonts found in
    there.

    Returns:
      printed output of all available fonts. To access a fontfile, use the
      fonts dictionary to access it.

      >>> fonts['fontname']

    To use a font, use the following sytax, where fontname is one of the
    printed fonts of this function:

    >>> ImageFont.truetype(fonts['fontname'], size = 10)
    """
    for fonts in available_fonts:
        print(fonts)


def get_system_tz() -> str:
    """Gets the system-timezone

    Gets the timezone set by the system.

    Returns:
      - A timezone if a system timezone was found.
      - UTC if no timezone was found.

    The extracted timezone can be used to show the local time instead of UTC. e.g.

      >>> import arrow
      >>> print(arrow.now()) # returns non-timezone-aware time
      >>> print(arrow.now(tz=get_system_tz()) # prints timezone aware time.
    """
    try:
        local_tz = tzlocal.get_localzone().key
        logs.debug(f"Local system timezone is {local_tz}.")
    except:
        logs.error("System timezone could not be parsed!")
        logs.error("Please set timezone manually!. Falling back to UTC...")
        local_tz = "UTC"
    logs.debug(f"The time is {arrow.now(tz=local_tz).format('YYYY-MM-DD HH:mm:ss ZZ')}.")
    return local_tz


def auto_fontsize(font, max_height):
    """Scales a given font to 80% of max_height.

    Gets the height of a font and scales it until 80% of the max_height
    is filled.


    Args:
        - font: A PIL Font object.
        - max_height: An integer representing the height to adjust the font to
          which the given font should be scaled to.

    Returns:
        A PIL font object with modified height.
    """
    text_bbox = font.getbbox("hg")
    text_height = text_bbox[3]
    fontsize = text_height
    while text_height <= (max_height * 0.80):
        fontsize += 1
        font = ImageFont.truetype(font.path, fontsize)
        text_height = text_bbox[3]
    return font


def write(image, xy, box_size, text, font=None, **kwargs):
    """Writes text on an image.

    Writes given text at given position on the specified image.

    Args:
      - image: The image to draw this text on, usually im_black or im_colour.
      - xy: tuple-> (x,y) representing the x and y co-ordinate.
      - box_size: tuple -> (width, height) representing the size of the text box.
      - text: string, the actual text to add on the image.
      - font: A PIL Font object e.g.
        ImageFont.truetype(fonts['fontname'], size = 10).

    Args: (optional)
      - alignment: alignment of the text, use 'center', 'left', 'right'.
      - autofit: bool (True/False). Automatically increases fontsize to fill in
        as much of the box-height as possible.
      - colour: black by default, do not change as it causes issues with rendering
        on e-Paper.
      - rotation: Rotate the text with the text-box by a given angle anti-clockwise.
      - fill_width: Decimal representing a percentage e.g. 0.9 # 90%. Fill
        maximum of 90% of the size of the full width of text-box.
      - fill_height: Decimal representing a percentage e.g. 0.9 # 90%. Fill
        maximum of 90% of the size of the full height of the text-box.
    """
    allowed_kwargs = ["alignment", "autofit", "colour", "rotation", "fill_width", "fill_height"]

    # Validate kwargs
    for key, value in kwargs.items():
        if key not in allowed_kwargs:
            print(f'{key} does not exist')

    # Set kwargs if given, it not, use defaults
    alignment = kwargs["alignment"] if "alignment" in kwargs else "center"
    autofit = kwargs["autofit"] if "autofit" in kwargs else False
    fill_width = kwargs["fill_width"] if "fill_width" in kwargs else 1.0
    fill_height = kwargs["fill_height"] if "fill_height" in kwargs else 0.8
    colour = kwargs["colour"] if "colour" in kwargs else "black"
    rotation = kwargs["rotation"] if "rotation" in kwargs else None

    x, y = xy
    box_width, box_height = box_size

    # Increase fontsize to fit specified height and width of text box
    if autofit or (fill_width != 1.0) or (fill_height != 0.8):
        size = 8
        font = ImageFont.truetype(font.path, size)
        text_bbox = font.getbbox(text)
        text_width = text_bbox[2] - text_bbox[0]
        text_bbox_height = font.getbbox("hg")
        text_height = text_bbox_height[3] - text_bbox_height[1]

        while text_width < int(box_width * fill_width) and text_height < int(box_height * fill_height):
            size += 1
            font = ImageFont.truetype(font.path, size)
            text_bbox = font.getbbox(text)
            text_width = text_bbox[2] - text_bbox[0]
            text_bbox_height = font.getbbox("hg")
            text_height = text_bbox_height[3] - text_bbox_height[1]

    text_bbox = font.getbbox(text)
    text_width = text_bbox[2] - text_bbox[0]
    text_bbox_height = font.getbbox("hg")
    text_height = text_bbox_height[3] - text_bbox_height[1]

    # Truncate text if text is too long, so it can fit inside the box
    if (text_width, text_height) > (box_width, box_height):
        logs.debug(("truncating {}".format(text)))
        while (text_width, text_height) > (box_width, box_height):
            text = text[0:-1]
            text_bbox = font.getbbox(text)
            text_width = text_bbox[2] - text_bbox[0]
            text_bbox_height = font.getbbox("hg")
            text_height = text_bbox_height[3] - text_bbox_height[1]
        logs.debug(text)

    # Align text to desired position
    if alignment == "center" or None:
        x = int((box_width / 2) - (text_width / 2))
    elif alignment == "left":
        x = 0
    elif alignment == "right":
        x = int(box_width - text_width)

    # Draw the text in the text-box
    draw = ImageDraw.Draw(image)
    space = Image.new('RGBA', (box_width, box_height))
    ImageDraw.Draw(space).text((x, 0), text, fill=colour, font=font)

    # Uncomment following two lines, comment out above two lines to show
    # red text-box with white text (debugging purposes)

    # space = Image.new('RGBA', (box_width, box_height), color= 'red')
    # ImageDraw.Draw(space).text((x, 0), text, fill='white', font=font, anchor="la")

    if rotation:
        space.rotate(rotation, expand=True)

    # Update only region with text (add text with transparent background)
    image.paste(space, xy, space)


def text_wrap(text, font=None, max_width=None):
    """Splits a very long text into smaller parts

    Splits a long text to smaller lines which can fit in a line with max_width.
    Uses a Font object for more accurate calculations.

    Args:
      - text -> Text as a string
      - font: A PIL font object which is used to calculate the size.
      - max_width: int-> a width in pixels defining the maximum width before
        splitting the text into the next chunk.

    Returns:
      A list containing chunked strings of the full text.
    """
    lines = []

    text_width = font.getlength(text)

    if text_width < max_width:
        lines.append(text)
    else:
        words = text.split(" ")
        i = 0
        while i < len(words):
            line = ""
            while i < len(words) and font.getlength(line + words[i]) <= max_width:
                line = line + words[i] + " "
                i += 1
            if not line:
                line = words[i]
                i += 1
            lines.append(line)
    return lines


def internet_available():
    """checks if the internet is available.

    Attempts to connect to google.com with a timeout of 5 seconds to check
    if the network can be reached.

    Returns:
      - True if connection could be established.
      - False if the internet could not be reached.

    Returned output can be used to add a check for internet availability:

    >>> if internet_available():
    >>> #...do something that requires internet connectivity
    """
    for attempt in range(3):
        try:
            requests.get("https://google.com", timeout=5)
            return True
        except:
            print(f"Network could not be reached: {traceback.print_exc()}")
            time.sleep(5)
    return False


def draw_border(image, xy, size, radius=5, thickness=1, shrinkage=(0.1, 0.1)):
    """Draws a border at given coordinates.

    Args:
      - image: The image on which the border should be drawn (usually im_black or
        im_colour.

      - xy: Tuple representing the top-left corner of the border e.g. (32, 100)
        where 32 is the x co-ordinate and 100 is the y-coordinate.

      - size: Size of the border as a tuple -> (width, height).

      - radius: Radius of the corners, where 0 = plain rectangle, 5 = round corners.

      - thickness: Thickness of the border in pixels.

      - shrinkage: A tuple containing decimals presenting a percentage of shrinking
        -> (width_shrink_percentage, height_shrink_percentage).
        e.g. (0.1, 0.2) ~ shrinks the width of border by 10%, shrinks height of
        border by 20%
    """

    colour = "black"

    # size from function parameter
    width, height = int(size[0] * (1 - shrinkage[0])), int(size[1] * (1 - shrinkage[1]))

    # shift cursor to move rectangle to center
    offset_x, offset_y = int((size[0] - width) / 2), int((size[1] - height) / 2)

    x, y, diameter = xy[0] + offset_x, xy[1] + offset_y, radius * 2
    # length of rectangle size
    a, b = (width - diameter), (height - diameter)

    # Set coordinates for straight lines
    p1, p2 = (x + radius, y), (x + radius + a, y)
    p3, p4 = (x + width, y + radius), (x + width, y + radius + b)
    p5, p6 = (p2[0], y + height), (p1[0], y + height)
    p7, p8 = (x, p4[1]), (x, p3[1])
    if radius != 0:
        # Set coordinates for arcs
        c1, c2 = (x, y), (x + diameter, y + diameter)
        c3, c4 = ((x + width) - diameter, y), (x + width, y + diameter)
        c5, c6 = ((x + width) - diameter, (y + height) - diameter), (x + width, y + height)
        c7, c8 = (x, (y + height) - diameter), (x + diameter, y + height)

    # Draw lines and arcs, creating a square with round corners
    draw = ImageDraw.Draw(image)
    draw.line((p1, p2), fill=colour, width=thickness)
    draw.line((p3, p4), fill=colour, width=thickness)
    draw.line((p5, p6), fill=colour, width=thickness)
    draw.line((p7, p8), fill=colour, width=thickness)

    if radius != 0:
        draw.arc((c1, c2), 180, 270, fill=colour, width=thickness)
        draw.arc((c3, c4), 270, 360, fill=colour, width=thickness)
        draw.arc((c5, c6), 0, 90, fill=colour, width=thickness)
        draw.arc((c7, c8), 90, 180, fill=colour, width=thickness)


def draw_border_2(im: PIL.Image, xy: tuple, size: tuple, radius: int):
    draw = ImageDraw.Draw(im)

    x, y = xy
    w, h = size

    draw.rounded_rectangle(xy=(x, y, x + w, y + h), outline="black", radius=radius)