Sith/core/utils.py

# -*- coding:utf-8 -*
#
# Copyright 2016,2017
# - Skia <skia@libskia.so>
#
# Ce fichier fait partie du site de l'Association des Étudiants de l'UTBM,
# http://ae.utbm.fr.
#
# This program is free software; you can redistribute it and/or modify it under
# the terms of the GNU General Public License a published by the Free Software
# Foundation; either version 3 of the License, or (at your option) any later
# version.
#
# This program is distributed in the hope that it will be useful, but WITHOUT
# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
# FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
# details.
#
# You should have received a copy of the GNU General Public License along with
# this program; if not, write to the Free Sofware Foundation, Inc., 59 Temple
# Place - Suite 330, Boston, MA 02111-1307, USA.
#
#

import re

# Image utils

from io import BytesIO
from PIL import Image, ExifTags
# from exceptions import IOError
import PIL
from django.core.files.base import ContentFile

def scale_dimension(width, height, long_edge):
    if width > height:
        ratio = long_edge * 1. / width
    else:
        ratio = long_edge * 1. / height
    return int(width * ratio), int(height * ratio)

def resize_image(im, edge, format):
    (w, h) = im.size
    (width, height) = scale_dimension(w, h, long_edge=edge)
    content = BytesIO()
    im = im.resize((width, height), PIL.Image.ANTIALIAS)
    try:
        im.save(fp=content, format=format.upper(), quality=90, optimize=True, progressive=True)
    except IOError:
        PIL.ImageFile.MAXBLOCK = im.size[0] * im.size[1]
        im.save(fp=content, format=format.upper(), quality=90, optimize=True, progressive=True)
    return ContentFile(content.getvalue())

def exif_auto_rotate(image):
    for orientation in ExifTags.TAGS.keys() :
        if ExifTags.TAGS[orientation]=='Orientation' : break
    exif=dict(image._getexif().items())

    if   exif[orientation] == 3 :
        image=image.rotate(180, expand=True)
    elif exif[orientation] == 6 :
        image=image.rotate(270, expand=True)
    elif exif[orientation] == 8 :
        image=image.rotate(90, expand=True)

    return image

def doku_to_markdown(text):
    text = re.sub(r'([^:]|^)\/\/(.*?)\/\/', r'*\2*', text) # Italic (prevents protocol:// conflict)
    text = re.sub(r'<del>(.*?)<\/del>', r'~~\1~~', text, flags=re.DOTALL) # Strike (may be multiline)
    text = re.sub(r'<sup>(.*?)<\/sup>', r'^\1^', text) # Superscript (multiline not supported, because almost never used)
    text = re.sub(r'<sub>(.*?)<\/sub>', r'_\1_', text) # Subscript (idem)

    text = re.sub(r'^======(.*?)======', r'#\1', text, flags=re.MULTILINE) # Titles
    text = re.sub(r'^=====(.*?)=====', r'##\1', text, flags=re.MULTILINE)
    text = re.sub(r'^====(.*?)====', r'###\1', text, flags=re.MULTILINE)
    text = re.sub(r'^===(.*?)===', r'####\1', text, flags=re.MULTILINE)
    text = re.sub(r'^==(.*?)==', r'#####\1', text, flags=re.MULTILINE)
    text = re.sub(r'^=(.*?)=', r'######\1', text, flags=re.MULTILINE)

    text = re.sub(r'<nowiki>', r'<nosyntax>', text)
    text = re.sub(r'</nowiki>', r'</nosyntax>', text)
    text = re.sub(r'<code>', r'```\n', text)
    text = re.sub(r'</code>', r'\n```', text)
    text = re.sub(r'article://', r'page://', text)
    text = re.sub(r'dfile://', r'file://', text)

    i = 1
    for fn in re.findall(r'\(\((.*?)\)\)', text): # Footnotes
        text = re.sub(r'\(\((.*?)\)\)', r'[^%s]' % i, text, count=1)
        text += "\n[^%s]: %s\n" % (i, fn)
        i += 1

    text = re.sub(r'\\{2,}[\s]', r'   \n', text) # Carriage return

    text = re.sub(r'\[\[(.*?)(\|(.*?))?\]\]', r'[\3](\1)', text) # Links
    text = re.sub(r'{{(.*?)(\|(.*?))?}}', r'![\3](\1 "\3")', text) # Images
    text = re.sub(r'{\[(.*?)(\|(.*?))?\]}', r'[\1](\1)', text) # Video (transform to classic links, since we can't integrate them)

    text = re.sub(r'###(\d*?)###', r'[[[\1]]]', text) # Progress bar

    text = re.sub(r'(\n +[^* -][^\n]*(\n +[^* -][^\n]*)*)', r'```\1\n```', text, flags=re.DOTALL) # Block code without lists

    text = re.sub(r'( +)-(.*)', r'1.\2', text) # Ordered lists

    new_text = []
    quote_level = 0
    for line in text.splitlines(): # Tables and quotes
        enter = re.finditer(r'\[quote(=(.+?))?\]', line)
        quit = re.finditer(r'\[/quote\]', line)
        if re.search(r'\A\s*\^(([^\^]*?)\^)*', line): # Table part
            line = line.replace('^', '|')
            new_text.append("> " * quote_level + line)
            new_text.append("> " * quote_level + "|---|") # Don't keep the text alignement in tables it's really too complex for what it's worth
        elif enter or quit: # Quote part
            for quote in enter: # Enter quotes (support multiple at a time)
                quote_level += 1
                try:
                    new_text.append("> " * quote_level + "##### " + quote.group(2))
                except:
                    new_text.append("> " * quote_level)
                line = line.replace(quote.group(0), '')
            final_quote_level = quote_level # Store quote_level to use at the end, since it will be modified during quit iteration
            final_newline = False
            for quote in quit: # Quit quotes (support multiple at a time)
                line = line.replace(quote.group(0), '')
                quote_level -= 1
                final_newline = True
            new_text.append("> " * final_quote_level + line) # Finally append the line
            if final_newline: new_text.append("\n") # Add a new line to ensure the separation between the quote and the following text
        else:
            new_text.append(line)

    return "\n".join(new_text)