# -*- coding: utf-8 -*- # # Copyright (C) 2022 Chris Caron <lead2gold@gmail.com> # All rights reserved. # # This code is licensed under the MIT License. # # Permission is hereby granted, free of charge, to any person obtaining a copy # of this software and associated documentation files(the "Software"), to deal # in the Software without restriction, including without limitation the rights # to use, copy, modify, merge, publish, distribute, sublicense, and / or sell # copies of the Software, and to permit persons to whom the Software is # furnished to do so, subject to the following conditions : # # The above copyright notice and this permission notice shall be included in # all copies or substantial portions of the Software. # # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR # IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, # FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.IN NO EVENT SHALL THE # AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER # LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN # THE SOFTWARE. import re #from markdown import markdown from .common import NotifyFormat from .URLBase import URLBase from html.parser import HTMLParser def convert_between(from_format, to_format, content): """ Converts between different suported formats. If no conversion exists, or the selected one fails, the original text will be returned. This function returns the content translated (if required) """ converters = { # (NotifyFormat.MARKDOWN, NotifyFormat.HTML): markdown_to_html, (NotifyFormat.TEXT, NotifyFormat.HTML): text_to_html, (NotifyFormat.HTML, NotifyFormat.TEXT): html_to_text, # For now; use same converter for Markdown support # (NotifyFormat.HTML, NotifyFormat.MARKDOWN): html_to_text, } convert = converters.get((from_format, to_format)) return convert(content) if convert else content #def markdown_to_html(content): # """ # Converts specified content from markdown to HTML. # """ # return markdown(content) def text_to_html(content): """ Converts specified content from plain text to HTML. """ # First eliminate any carriage returns return URLBase.escape_html(content, convert_new_lines=True) def html_to_text(content): """ Converts a content from HTML to plain text. """ parser = HTMLConverter() parser.feed(content) parser.close() return parser.converted class HTMLConverter(HTMLParser, object): """An HTML to plain text converter tuned for email messages.""" # The following tags must start on a new line BLOCK_TAGS = ('p', 'h1', 'h2', 'h3', 'h4', 'h5', 'h6', 'div', 'td', 'th', 'code', 'pre', 'label', 'li',) # the folowing tags ignore any internal text IGNORE_TAGS = ( 'form', 'input', 'textarea', 'select', 'ul', 'ol', 'style', 'link', 'meta', 'title', 'html', 'head', 'script') # Condense Whitespace WS_TRIM = re.compile(r'[\s]+', re.DOTALL | re.MULTILINE) # Sentinel value for block tag boundaries, which may be consolidated into a # single line break. BLOCK_END = {} def __init__(self, **kwargs): super().__init__(**kwargs) # Shoudl we store the text content or not? self._do_store = True # Initialize internal result list self._result = [] # Initialize public result field (not populated until close() is # called) self.converted = "" def close(self): string = ''.join(self._finalize(self._result)) self.converted = string.strip() def _finalize(self, result): """ Combines and strips consecutive strings, then converts consecutive block ends into singleton newlines. [ {be} " Hello " {be} {be} " World!" ] -> "\nHello\nWorld!" """ # None means the last visited item was a block end. accum = None for item in result: if item == self.BLOCK_END: # Multiple consecutive block ends; do nothing. if accum is None: continue # First block end; yield the current string, plus a newline. yield accum.strip() + '\n' accum = None # Multiple consecutive strings; combine them. elif accum is not None: accum += item # First consecutive string; store it. else: accum = item # Yield the last string if we have not already done so. if accum is not None: yield accum.strip() def handle_data(self, data, *args, **kwargs): """ Store our data if it is not on the ignore list """ # initialize our previous flag if self._do_store: # Tidy our whitespace content = self.WS_TRIM.sub(' ', data) self._result.append(content) def handle_starttag(self, tag, attrs): """ Process our starting HTML Tag """ # Toggle initial states self._do_store = tag not in self.IGNORE_TAGS if tag in self.BLOCK_TAGS: self._result.append(self.BLOCK_END) if tag == 'li': self._result.append('- ') elif tag == 'br': self._result.append('\n') elif tag == 'hr': if self._result: self._result[-1] = self._result[-1].rstrip(' ') self._result.append('\n---\n') elif tag == 'blockquote': self._result.append(' >') def handle_endtag(self, tag): """ Edge case handling of open/close tags """ self._do_store = True if tag in self.BLOCK_TAGS: self._result.append(self.BLOCK_END)