forked from mirrors/bookwyrm
474 lines
15 KiB
Python
474 lines
15 KiB
Python
""" Generate social media preview images for twitter/mastodon/etc """
|
|
import math
|
|
import os
|
|
import textwrap
|
|
from io import BytesIO
|
|
from uuid import uuid4
|
|
import logging
|
|
|
|
import colorsys
|
|
from colorthief import ColorThief
|
|
from PIL import Image, ImageDraw, ImageFont, ImageOps, ImageColor
|
|
|
|
from django.core.files.base import ContentFile
|
|
from django.core.files.uploadedfile import InMemoryUploadedFile
|
|
from django.core.files.storage import default_storage
|
|
from django.db.models import Avg
|
|
|
|
from bookwyrm import models, settings
|
|
from bookwyrm.tasks import app
|
|
|
|
logger = logging.getLogger(__name__)
|
|
|
|
IMG_WIDTH = settings.PREVIEW_IMG_WIDTH
|
|
IMG_HEIGHT = settings.PREVIEW_IMG_HEIGHT
|
|
BG_COLOR = settings.PREVIEW_BG_COLOR
|
|
TEXT_COLOR = settings.PREVIEW_TEXT_COLOR
|
|
DEFAULT_COVER_COLOR = settings.PREVIEW_DEFAULT_COVER_COLOR
|
|
DEFAULT_FONT = settings.PREVIEW_DEFAULT_FONT
|
|
TRANSPARENT_COLOR = (0, 0, 0, 0)
|
|
|
|
margin = math.floor(IMG_HEIGHT / 10)
|
|
gutter = math.floor(margin / 2)
|
|
inner_img_height = math.floor(IMG_HEIGHT * 0.8)
|
|
inner_img_width = math.floor(inner_img_height * 0.7)
|
|
|
|
|
|
def get_imagefont(name, size):
|
|
"""Loads an ImageFont based on config"""
|
|
try:
|
|
config = settings.FONTS[name]
|
|
path = os.path.join(settings.FONT_DIR, config["directory"], config["filename"])
|
|
return ImageFont.truetype(path, size)
|
|
except KeyError:
|
|
logger.error("Font %s not found in config", name)
|
|
except OSError:
|
|
logger.error("Could not load font %s from file", name)
|
|
|
|
return ImageFont.load_default()
|
|
|
|
|
|
def get_font(weight, size=28):
|
|
"""Gets a custom font with the given weight and size"""
|
|
font = get_imagefont(DEFAULT_FONT, size)
|
|
|
|
try:
|
|
if weight == "light":
|
|
font.set_variation_by_name("Light")
|
|
if weight == "bold":
|
|
font.set_variation_by_name("Bold")
|
|
if weight == "regular":
|
|
font.set_variation_by_name("Regular")
|
|
except AttributeError:
|
|
pass
|
|
|
|
return font
|
|
|
|
|
|
def get_wrapped_text(text, font, content_width):
|
|
"""text wrap length depends on the max width of the content"""
|
|
|
|
low = 0
|
|
high = len(text)
|
|
|
|
try:
|
|
# ideal length is determined via binary search
|
|
while low < high:
|
|
mid = math.floor(low + high)
|
|
wrapped_text = textwrap.fill(text, width=mid)
|
|
width = font.getsize_multiline(wrapped_text)[0]
|
|
if width < content_width:
|
|
low = mid
|
|
else:
|
|
high = mid - 1
|
|
except AttributeError:
|
|
wrapped_text = text
|
|
|
|
return wrapped_text
|
|
|
|
|
|
def generate_texts_layer(texts, content_width):
|
|
"""Adds text for images"""
|
|
font_text_zero = get_font("bold", size=20)
|
|
font_text_one = get_font("bold", size=48)
|
|
font_text_two = get_font("bold", size=40)
|
|
font_text_three = get_font("regular", size=40)
|
|
|
|
text_layer = Image.new("RGBA", (content_width, IMG_HEIGHT), color=TRANSPARENT_COLOR)
|
|
text_layer_draw = ImageDraw.Draw(text_layer)
|
|
|
|
text_y = 0
|
|
|
|
if "text_zero" in texts and texts["text_zero"]:
|
|
# Text one (Book title)
|
|
text_zero = get_wrapped_text(texts["text_zero"], font_text_zero, content_width)
|
|
|
|
text_layer_draw.multiline_text(
|
|
(0, text_y), text_zero, font=font_text_zero, fill=TEXT_COLOR
|
|
)
|
|
|
|
try:
|
|
text_y = text_y + font_text_zero.getsize_multiline(text_zero)[1] + 16
|
|
except (AttributeError, IndexError):
|
|
text_y = text_y + 26
|
|
|
|
if "text_one" in texts and texts["text_one"]:
|
|
# Text one (Book title)
|
|
text_one = get_wrapped_text(texts["text_one"], font_text_one, content_width)
|
|
|
|
text_layer_draw.multiline_text(
|
|
(0, text_y), text_one, font=font_text_one, fill=TEXT_COLOR
|
|
)
|
|
|
|
try:
|
|
text_y = text_y + font_text_one.getsize_multiline(text_one)[1] + 16
|
|
except (AttributeError, IndexError):
|
|
text_y = text_y + 26
|
|
|
|
if "text_two" in texts and texts["text_two"]:
|
|
# Text one (Book subtitle)
|
|
text_two = get_wrapped_text(texts["text_two"], font_text_two, content_width)
|
|
|
|
text_layer_draw.multiline_text(
|
|
(0, text_y), text_two, font=font_text_two, fill=TEXT_COLOR
|
|
)
|
|
|
|
try:
|
|
text_y = text_y + font_text_one.getsize_multiline(text_two)[1] + 16
|
|
except (AttributeError, IndexError):
|
|
text_y = text_y + 26
|
|
|
|
if "text_three" in texts and texts["text_three"]:
|
|
# Text three (Book authors)
|
|
text_three = get_wrapped_text(
|
|
texts["text_three"], font_text_three, content_width
|
|
)
|
|
|
|
text_layer_draw.multiline_text(
|
|
(0, text_y), text_three, font=font_text_three, fill=TEXT_COLOR
|
|
)
|
|
|
|
text_layer_box = text_layer.getbbox()
|
|
return text_layer.crop(text_layer_box)
|
|
|
|
|
|
def generate_instance_layer(content_width):
|
|
"""Places components for instance preview"""
|
|
font_instance = get_font("light", size=28)
|
|
|
|
site = models.SiteSettings.objects.get()
|
|
|
|
if site.logo_small:
|
|
logo_img = Image.open(site.logo_small)
|
|
else:
|
|
try:
|
|
static_path = os.path.join(settings.STATIC_ROOT, "images/logo-small.png")
|
|
logo_img = Image.open(static_path)
|
|
except FileNotFoundError:
|
|
logo_img = None
|
|
|
|
instance_layer = Image.new("RGBA", (content_width, 62), color=TRANSPARENT_COLOR)
|
|
|
|
instance_text_x = 0
|
|
|
|
if logo_img:
|
|
logo_img.thumbnail((50, 50), Image.ANTIALIAS)
|
|
|
|
instance_layer.paste(logo_img, (0, 0))
|
|
|
|
instance_text_x = instance_text_x + 60
|
|
|
|
instance_layer_draw = ImageDraw.Draw(instance_layer)
|
|
instance_layer_draw.text(
|
|
(instance_text_x, 10), site.name, font=font_instance, fill=TEXT_COLOR
|
|
)
|
|
|
|
line_width = 50 + 10 + font_instance.getsize(site.name)[0]
|
|
|
|
line_layer = Image.new(
|
|
"RGBA", (line_width, 2), color=(*(ImageColor.getrgb(TEXT_COLOR)), 50)
|
|
)
|
|
instance_layer.alpha_composite(line_layer, (0, 60))
|
|
|
|
return instance_layer
|
|
|
|
|
|
def generate_rating_layer(rating, content_width):
|
|
"""Places components for rating preview"""
|
|
try:
|
|
icon_star_full = Image.open(
|
|
os.path.join(settings.STATIC_ROOT, "images/icons/star-full.png")
|
|
)
|
|
icon_star_empty = Image.open(
|
|
os.path.join(settings.STATIC_ROOT, "images/icons/star-empty.png")
|
|
)
|
|
icon_star_half = Image.open(
|
|
os.path.join(settings.STATIC_ROOT, "images/icons/star-half.png")
|
|
)
|
|
except FileNotFoundError:
|
|
return None
|
|
|
|
icon_size = 64
|
|
icon_margin = 10
|
|
|
|
rating_layer_base = Image.new(
|
|
"RGBA", (content_width, icon_size), color=TRANSPARENT_COLOR
|
|
)
|
|
rating_layer_color = Image.new("RGBA", (content_width, icon_size), color=TEXT_COLOR)
|
|
rating_layer_mask = Image.new(
|
|
"RGBA", (content_width, icon_size), color=TRANSPARENT_COLOR
|
|
)
|
|
|
|
position_x = 0
|
|
|
|
for _ in range(math.floor(rating)):
|
|
rating_layer_mask.alpha_composite(icon_star_full, (position_x, 0))
|
|
position_x = position_x + icon_size + icon_margin
|
|
|
|
if math.floor(rating) != math.ceil(rating):
|
|
rating_layer_mask.alpha_composite(icon_star_half, (position_x, 0))
|
|
position_x = position_x + icon_size + icon_margin
|
|
|
|
for _ in range(5 - math.ceil(rating)):
|
|
rating_layer_mask.alpha_composite(icon_star_empty, (position_x, 0))
|
|
position_x = position_x + icon_size + icon_margin
|
|
|
|
rating_layer_mask = rating_layer_mask.getchannel("A")
|
|
rating_layer_mask = ImageOps.invert(rating_layer_mask)
|
|
|
|
rating_layer_composite = Image.composite(
|
|
rating_layer_base, rating_layer_color, rating_layer_mask
|
|
)
|
|
|
|
return rating_layer_composite
|
|
|
|
|
|
def generate_default_inner_img():
|
|
"""Adds cover image"""
|
|
font_cover = get_font("light", size=28)
|
|
|
|
default_cover = Image.new(
|
|
"RGB", (inner_img_width, inner_img_height), color=DEFAULT_COVER_COLOR
|
|
)
|
|
default_cover_draw = ImageDraw.Draw(default_cover)
|
|
|
|
text = "no image :("
|
|
text_dimensions = font_cover.getsize(text)
|
|
text_coords = (
|
|
math.floor((inner_img_width - text_dimensions[0]) / 2),
|
|
math.floor((inner_img_height - text_dimensions[1]) / 2),
|
|
)
|
|
default_cover_draw.text(text_coords, text, font=font_cover, fill="white")
|
|
|
|
return default_cover
|
|
|
|
|
|
# pylint: disable=too-many-locals
|
|
# pylint: disable=too-many-statements
|
|
def generate_preview_image(
|
|
texts=None, picture=None, rating=None, show_instance_layer=True
|
|
):
|
|
"""Puts everything together"""
|
|
texts = texts or {}
|
|
# Cover
|
|
try:
|
|
inner_img_layer = Image.open(picture)
|
|
inner_img_layer.thumbnail((inner_img_width, inner_img_height), Image.ANTIALIAS)
|
|
color_thief = ColorThief(picture)
|
|
dominant_color = color_thief.get_color(quality=1)
|
|
except: # pylint: disable=bare-except
|
|
inner_img_layer = generate_default_inner_img()
|
|
dominant_color = ImageColor.getrgb(DEFAULT_COVER_COLOR)
|
|
|
|
# Color
|
|
if BG_COLOR in ["use_dominant_color_light", "use_dominant_color_dark"]:
|
|
red, green, blue = dominant_color
|
|
image_bg_color = f"rgb({red}, {green}, {blue})"
|
|
|
|
# Adjust color
|
|
image_bg_color_rgb = [x / 255.0 for x in ImageColor.getrgb(image_bg_color)]
|
|
image_bg_color_hls = colorsys.rgb_to_hls(*image_bg_color_rgb)
|
|
|
|
if BG_COLOR == "use_dominant_color_light":
|
|
lightness = max(0.9, image_bg_color_hls[1])
|
|
else:
|
|
lightness = min(0.15, image_bg_color_hls[1])
|
|
|
|
image_bg_color_hls = (
|
|
image_bg_color_hls[0],
|
|
lightness,
|
|
image_bg_color_hls[2],
|
|
)
|
|
image_bg_color = tuple(
|
|
math.ceil(x * 255) for x in colorsys.hls_to_rgb(*image_bg_color_hls)
|
|
)
|
|
else:
|
|
image_bg_color = BG_COLOR
|
|
|
|
# Background (using the color)
|
|
img = Image.new("RGBA", (IMG_WIDTH, IMG_HEIGHT), color=image_bg_color)
|
|
|
|
# Contents
|
|
inner_img_x = margin + inner_img_width - inner_img_layer.width
|
|
inner_img_y = math.floor((IMG_HEIGHT - inner_img_layer.height) / 2)
|
|
content_x = margin + inner_img_width + gutter
|
|
content_width = IMG_WIDTH - content_x - margin
|
|
|
|
contents_layer = Image.new(
|
|
"RGBA", (content_width, IMG_HEIGHT), color=TRANSPARENT_COLOR
|
|
)
|
|
contents_composite_y = 0
|
|
|
|
if show_instance_layer:
|
|
instance_layer = generate_instance_layer(content_width)
|
|
contents_layer.alpha_composite(instance_layer, (0, contents_composite_y))
|
|
contents_composite_y = contents_composite_y + instance_layer.height + gutter
|
|
|
|
texts_layer = generate_texts_layer(texts, content_width)
|
|
contents_layer.alpha_composite(texts_layer, (0, contents_composite_y))
|
|
contents_composite_y = contents_composite_y + texts_layer.height + gutter
|
|
|
|
if rating:
|
|
# Add some more margin
|
|
contents_composite_y = contents_composite_y + gutter
|
|
rating_layer = generate_rating_layer(rating, content_width)
|
|
|
|
if rating_layer:
|
|
contents_layer.alpha_composite(rating_layer, (0, contents_composite_y))
|
|
contents_composite_y = contents_composite_y + rating_layer.height + gutter
|
|
|
|
contents_layer_box = contents_layer.getbbox()
|
|
contents_layer_height = contents_layer_box[3] - contents_layer_box[1]
|
|
|
|
contents_y = math.floor((IMG_HEIGHT - contents_layer_height) / 2)
|
|
|
|
if show_instance_layer:
|
|
# Remove Instance Layer from centering calculations
|
|
contents_y = contents_y - math.floor((instance_layer.height + gutter) / 2)
|
|
|
|
contents_y = max(contents_y, margin)
|
|
|
|
# Composite layers
|
|
img.paste(
|
|
inner_img_layer, (inner_img_x, inner_img_y), inner_img_layer.convert("RGBA")
|
|
)
|
|
img.alpha_composite(contents_layer, (content_x, contents_y))
|
|
|
|
return img.convert("RGB")
|
|
|
|
|
|
def save_and_cleanup(image, instance=None):
|
|
"""Save and close the file"""
|
|
if not isinstance(instance, (models.Book, models.User, models.SiteSettings)):
|
|
return False
|
|
image_buffer = BytesIO()
|
|
|
|
try:
|
|
try:
|
|
file_name = instance.preview_image.name
|
|
except ValueError:
|
|
file_name = None
|
|
|
|
if not file_name or file_name == "":
|
|
uuid = uuid4()
|
|
file_name = f"{instance.id}-{uuid}.jpg"
|
|
|
|
# Clean up old file before saving
|
|
if file_name and default_storage.exists(file_name):
|
|
default_storage.delete(file_name)
|
|
|
|
# Save
|
|
image.save(image_buffer, format="jpeg", quality=75)
|
|
|
|
instance.preview_image = InMemoryUploadedFile(
|
|
ContentFile(image_buffer.getvalue()),
|
|
"preview_image",
|
|
file_name,
|
|
"image/jpg",
|
|
image_buffer.tell(),
|
|
None,
|
|
)
|
|
|
|
save_without_broadcast = isinstance(instance, (models.Book, models.User))
|
|
if save_without_broadcast:
|
|
instance.save(broadcast=False, update_fields=["preview_image"])
|
|
else:
|
|
instance.save(update_fields=["preview_image"])
|
|
|
|
finally:
|
|
image_buffer.close()
|
|
return True
|
|
|
|
|
|
# pylint: disable=invalid-name
|
|
@app.task(queue="low_priority")
|
|
def generate_site_preview_image_task():
|
|
"""generate preview_image for the website"""
|
|
if not settings.ENABLE_PREVIEW_IMAGES:
|
|
return
|
|
|
|
site = models.SiteSettings.objects.get()
|
|
|
|
if site.logo:
|
|
logo = site.logo
|
|
else:
|
|
logo = os.path.join(settings.STATIC_ROOT, "images/logo.png")
|
|
|
|
texts = {
|
|
"text_zero": settings.DOMAIN,
|
|
"text_one": site.name,
|
|
"text_three": site.instance_tagline,
|
|
}
|
|
|
|
image = generate_preview_image(texts=texts, picture=logo, show_instance_layer=False)
|
|
|
|
save_and_cleanup(image, instance=site)
|
|
|
|
|
|
# pylint: disable=invalid-name
|
|
@app.task(queue="low_priority")
|
|
def generate_edition_preview_image_task(book_id):
|
|
"""generate preview_image for a book"""
|
|
if not settings.ENABLE_PREVIEW_IMAGES:
|
|
return
|
|
|
|
book = models.Book.objects.select_subclasses().get(id=book_id)
|
|
|
|
rating = models.Review.objects.filter(
|
|
privacy="public",
|
|
deleted=False,
|
|
book__in=[book_id],
|
|
).aggregate(Avg("rating"))["rating__avg"]
|
|
|
|
texts = {
|
|
"text_one": book.title,
|
|
"text_two": book.subtitle,
|
|
"text_three": book.author_text,
|
|
}
|
|
|
|
image = generate_preview_image(texts=texts, picture=book.cover, rating=rating)
|
|
|
|
save_and_cleanup(image, instance=book)
|
|
|
|
|
|
@app.task(queue="low_priority")
|
|
def generate_user_preview_image_task(user_id):
|
|
"""generate preview_image for a book"""
|
|
if not settings.ENABLE_PREVIEW_IMAGES:
|
|
return
|
|
|
|
user = models.User.objects.get(id=user_id)
|
|
|
|
texts = {
|
|
"text_one": user.display_name,
|
|
"text_three": f"@{user.localname}@{settings.DOMAIN}",
|
|
}
|
|
|
|
if user.avatar:
|
|
avatar = user.avatar
|
|
else:
|
|
avatar = os.path.join(settings.STATIC_ROOT, "images/default_avi.jpg")
|
|
|
|
image = generate_preview_image(texts=texts, picture=avatar)
|
|
|
|
save_and_cleanup(image, instance=user)
|