kopia lustrzana https://github.com/ihabunek/toot
303 wiersze
9.9 KiB
Python
303 wiersze
9.9 KiB
Python
"""
|
|
richtext
|
|
"""
|
|
from typing import List, Tuple
|
|
import urwid
|
|
import unicodedata
|
|
|
|
from toot.utils import bs4_parse
|
|
from .constants import PALETTE
|
|
from bs4.element import NavigableString, Tag
|
|
|
|
|
|
PALETTE_NAMES = [name for name, _, _ in PALETTE]
|
|
|
|
|
|
class ContentParser:
|
|
"""Parse a limited subset of HTML and create urwid widgets."""
|
|
|
|
def html_to_widgets(self, html) -> List[urwid.Widget]:
|
|
"""Convert html to urwid widgets"""
|
|
widgets: List[urwid.Widget] = []
|
|
html = unicodedata.normalize("NFKC", html)
|
|
soup = bs4_parse(html)
|
|
|
|
for e in soup.body or soup:
|
|
if isinstance(e, NavigableString):
|
|
continue
|
|
name = e.name
|
|
# First, look for a custom tag handler method in this class
|
|
# If that fails, fall back to inline_tag_to_text handler
|
|
method = getattr(self, "_" + name, self.inline_tag_to_text)
|
|
markup = method(e) # either returns a Widget, or plain text
|
|
|
|
if not isinstance(markup, urwid.Widget):
|
|
# plaintext, so create a padded text widget
|
|
txt = urwid.Text(markup)
|
|
markup = urwid.Padding(
|
|
txt,
|
|
align="left",
|
|
width=("relative", 100),
|
|
min_width=None,
|
|
)
|
|
widgets.append(markup)
|
|
# separate top level widgets with a blank line
|
|
widgets.append(urwid.Divider(" "))
|
|
return widgets[:-1] # but suppress the last blank line
|
|
|
|
def inline_tag_to_text(self, tag) -> Tuple:
|
|
"""Convert html tag to plain text with tag as attributes recursively"""
|
|
markups = self.process_inline_tag_children(tag)
|
|
if not markups:
|
|
return (tag.name, "")
|
|
return (tag.name, markups)
|
|
|
|
def process_inline_tag_children(self, tag) -> List:
|
|
"""Recursively retrieve all children
|
|
and convert to a list of markup text"""
|
|
markups = []
|
|
for child in tag.children:
|
|
if isinstance(child, Tag):
|
|
method = getattr(self, "_" + child.name, self.inline_tag_to_text)
|
|
markup = method(child)
|
|
markups.append(markup)
|
|
else:
|
|
markups.append(child)
|
|
return markups
|
|
|
|
def process_block_tag_children(self, tag) -> List[urwid.Widget]:
|
|
"""Recursively retrieve all children
|
|
and convert to a list of widgets
|
|
any inline tags containing text will be
|
|
converted to Text widgets"""
|
|
|
|
pre_widget_markups = []
|
|
post_widget_markups = []
|
|
child_widgets = []
|
|
found_nested_widget = False
|
|
|
|
for child in tag.children:
|
|
if isinstance(child, Tag):
|
|
# child is a nested tag; process using custom method
|
|
# or default to inline_tag_to_text
|
|
method = getattr(self, "_" + child.name, self.inline_tag_to_text)
|
|
result = method(child)
|
|
if isinstance(result, urwid.Widget):
|
|
found_nested_widget = True
|
|
child_widgets.append(result)
|
|
else:
|
|
if not found_nested_widget:
|
|
pre_widget_markups.append(result)
|
|
else:
|
|
post_widget_markups.append(result)
|
|
else:
|
|
# child is text; append to the appropriate markup list
|
|
if not found_nested_widget:
|
|
pre_widget_markups.append(child)
|
|
else:
|
|
post_widget_markups.append(child)
|
|
|
|
widget_list = []
|
|
if len(pre_widget_markups):
|
|
widget_list.append(urwid.Text((tag.name, pre_widget_markups)))
|
|
|
|
if len(child_widgets):
|
|
widget_list += child_widgets
|
|
|
|
if len(post_widget_markups):
|
|
widget_list.append(urwid.Text((tag.name, post_widget_markups)))
|
|
|
|
return widget_list
|
|
|
|
def get_urwid_attr_name(self, tag) -> str:
|
|
"""Get the class name and translate to a
|
|
name suitable for use as an urwid
|
|
text attribute name"""
|
|
|
|
if "class" in tag.attrs:
|
|
clss = tag.attrs["class"]
|
|
if len(clss) > 0:
|
|
style_name = "class_" + "_".join(clss)
|
|
# return the class name, only if we
|
|
# find it as a defined palette name
|
|
if style_name in PALETTE_NAMES:
|
|
return style_name
|
|
|
|
# fallback to returning the tag name
|
|
return tag.name
|
|
|
|
# Tag handlers start here.
|
|
# Tags not explicitly listed are "supported" by
|
|
# rendering as text.
|
|
# Inline tags return a list of marked up text for urwid.Text
|
|
# Block tags return urwid.Widget
|
|
|
|
def basic_block_tag_handler(self, tag) -> urwid.Widget:
|
|
"""default for block tags that need no special treatment"""
|
|
return urwid.Pile(self.process_block_tag_children(tag))
|
|
|
|
def _a(self, tag) -> Tuple:
|
|
markups = self.process_inline_tag_children(tag)
|
|
if not markups:
|
|
return (tag.name, "")
|
|
|
|
# hashtag anchors have a class of "mention hashtag"
|
|
# we'll return style "class_mention_hashtag"
|
|
# in that case; see corresponding palette entry
|
|
# in constants.py controlling hashtag highlighting
|
|
|
|
return (self.get_urwid_attr_name(tag), markups)
|
|
|
|
def _blockquote(self, tag) -> urwid.Widget:
|
|
widget_list = self.process_block_tag_children(tag)
|
|
blockquote_widget = urwid.LineBox(
|
|
urwid.Padding(
|
|
urwid.Pile(widget_list),
|
|
align="left",
|
|
width=("relative", 100),
|
|
min_width=None,
|
|
left=1,
|
|
right=1,
|
|
),
|
|
tlcorner="",
|
|
tline="",
|
|
lline="│",
|
|
trcorner="",
|
|
blcorner="",
|
|
rline="",
|
|
bline="",
|
|
brcorner="",
|
|
)
|
|
return urwid.Pile([urwid.AttrMap(blockquote_widget, "blockquote")])
|
|
|
|
def _br(self, tag) -> Tuple:
|
|
return ("br", "\n")
|
|
|
|
def _em(self, tag) -> Tuple:
|
|
# to simplify the number of palette entries
|
|
# translate EM to I (italic)
|
|
markups = self.process_inline_tag_children(tag)
|
|
if not markups:
|
|
return ("i", "")
|
|
|
|
# special case processing for bold and italic
|
|
for parent in tag.parents:
|
|
if parent.name == "b" or parent.name == "strong":
|
|
return ("bi", markups)
|
|
|
|
return ("i", markups)
|
|
|
|
def _ol(self, tag) -> urwid.Widget:
|
|
return self.list_widget(tag, ordered=True)
|
|
|
|
def _pre(self, tag) -> urwid.Widget:
|
|
|
|
# <PRE> tag spec says that text should not wrap,
|
|
# but horizontal screen space is at a premium
|
|
# and we have no horizontal scroll bar, so allow
|
|
# wrapping.
|
|
|
|
widget_list = [urwid.Divider(" ")]
|
|
widget_list += self.process_block_tag_children(tag)
|
|
|
|
pre_widget = urwid.Padding(
|
|
urwid.Pile(widget_list),
|
|
align="left",
|
|
width=("relative", 100),
|
|
min_width=None,
|
|
left=1,
|
|
right=1,
|
|
)
|
|
return urwid.Pile([urwid.AttrMap(pre_widget, "pre")])
|
|
|
|
def _span(self, tag) -> Tuple:
|
|
markups = self.process_inline_tag_children(tag)
|
|
|
|
if not markups:
|
|
return (tag.name, "")
|
|
|
|
# span inherits its parent's class definition
|
|
# unless it has a specific class definition
|
|
# of its own
|
|
|
|
if "class" in tag.attrs:
|
|
style_name = self.get_urwid_attr_name(tag)
|
|
if style_name != "span":
|
|
# unique class name matches an entry in our palette
|
|
return (style_name, markups)
|
|
|
|
if tag.parent:
|
|
return (self.get_urwid_attr_name(tag.parent), markups)
|
|
else:
|
|
# fallback
|
|
return ("span", markups)
|
|
|
|
def _strong(self, tag) -> Tuple:
|
|
# to simplify the number of palette entries
|
|
# translate STRONG to B (bold)
|
|
markups = self.process_inline_tag_children(tag)
|
|
if not markups:
|
|
return ("b", "")
|
|
|
|
# special case processing for bold and italic
|
|
for parent in tag.parents:
|
|
if parent.name == "i" or parent.name == "em":
|
|
return ("bi", markups)
|
|
|
|
return ("b", markups)
|
|
|
|
def _ul(self, tag) -> urwid.Widget:
|
|
return self.list_widget(tag, ordered=False)
|
|
|
|
def list_widget(self, tag, ordered=False) -> urwid.Widget:
|
|
"""common logic for ordered and unordered list rendering
|
|
as urwid widgets"""
|
|
widgets = []
|
|
i = 1
|
|
for li in tag.find_all("li", recursive=False):
|
|
method = getattr(self, "_li", self.inline_tag_to_text)
|
|
markup = method(li)
|
|
|
|
if not isinstance(markup, urwid.Widget):
|
|
if ordered:
|
|
txt = urwid.Text(
|
|
("li", [str(i), ". ", markup])
|
|
) # 1. foo, 2. bar, etc.
|
|
else:
|
|
txt = urwid.Text(
|
|
("li", ["\N{bullet} ", markup])
|
|
) # * foo, * bar, etc.
|
|
widgets.append(txt)
|
|
else:
|
|
if ordered:
|
|
txt = urwid.Text(("li", [str(i) + "."]))
|
|
else:
|
|
txt = urwid.Text(("li", "\N{bullet}"))
|
|
|
|
columns = urwid.Columns(
|
|
[txt, ("weight", 9999, markup)], dividechars=1, min_width=3
|
|
)
|
|
widgets.append(columns)
|
|
i += 1
|
|
|
|
return urwid.Pile(widgets)
|
|
|
|
# These tags are handled identically to others
|
|
# the only difference being the tag name used for
|
|
# urwid attribute mapping
|
|
|
|
_b = _strong
|
|
|
|
_div = basic_block_tag_handler
|
|
|
|
_i = _em
|
|
|
|
_li = basic_block_tag_handler
|
|
|
|
# Glitch-soc and Pleroma allow <H1>...<H6> in content
|
|
# Mastodon (PR #23913) does not; header tags are converted to <P><STRONG></STRONG></P>
|
|
|
|
_h1 = _h2 = _h3 = _h4 = _h5 = _h6 = basic_block_tag_handler
|
|
|
|
_p = basic_block_tag_handler
|