qutebrowser/qutebrowser/browser/hints.py
2014-05-05 20:28:29 +02:00

489 lines
18 KiB
Python

# Copyright 2014 Florian Bruhin (The Compiler) <mail@qutebrowser.org>
#
# This file is part of qutebrowser.
#
# qutebrowser is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# qutebrowser 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 qutebrowser. If not, see <http://www.gnu.org/licenses/>.
"""A HintManager to draw hints over links."""
import logging
import math
from collections import namedtuple
from PyQt5.QtCore import pyqtSignal, pyqtSlot, QObject, QEvent, Qt
from PyQt5.QtGui import QMouseEvent, QClipboard
from PyQt5.QtWidgets import QApplication
import qutebrowser.config.config as config
import qutebrowser.keyinput.modeman as modeman
import qutebrowser.utils.message as message
import qutebrowser.utils.url as urlutils
import qutebrowser.utils.webelem as webelem
import qutebrowser.commands.utils as cmdutils
from qutebrowser.utils.usertypes import enum
ElemTuple = namedtuple('ElemTuple', 'elem, label')
Target = enum('normal', 'tab', 'bgtab', 'yank', 'yank_primary', 'cmd',
'cmd_tab', 'cmd_bgtab', 'rapid')
class HintManager(QObject):
"""Manage drawing hints over links or other elements.
Class attributes:
HINT_CSS: The CSS template to use for hints.
Attributes:
_frame: The QWebFrame to use.
_elems: A mapping from keystrings to (elem, label) namedtuples.
_baseurl: The URL of the current page.
_target: What to do with the opened links.
normal/tab/bgtab: Get passed to BrowserTab.
yank/yank_primary: Yank to clipboard/primary selection
cmd/cmd_tab/cmd_bgtab: Enter link to commandline
rapid: Rapid mode with background tabs
_to_follow: The link to follow when enter is pressed.
Signals:
hint_strings_updated: Emitted when the possible hint strings changed.
arg: A list of hint strings.
mouse_event: Mouse event to be posted in the web view.
arg: A QMouseEvent
openurl: Open a new url
arg 0: URL to open as QUrl.
arg 1: True if it should be opened in a new tab, else False.
set_open_target: Set a new target to open the links in.
"""
HINT_CSS = """
color: {config[colors][hints.fg]};
background: {config[colors][hints.bg]};
font: {config[fonts][hints]};
border: {config[hints][border]};
opacity: {config[hints][opacity]};
z-index: 100000;
pointer-events: none;
position: absolute;
left: {left}px;
top: {top}px;
"""
hint_strings_updated = pyqtSignal(list)
mouse_event = pyqtSignal('QMouseEvent')
openurl = pyqtSignal('QUrl', bool)
set_open_target = pyqtSignal(str)
def __init__(self, parent=None):
"""Constructor.
Args:
frame: The QWebFrame to use for finding elements and drawing.
"""
super().__init__(parent)
self._elems = {}
self._frame = None
self._target = None
self._baseurl = None
self._to_follow = None
modeman.instance().left.connect(self.on_mode_left)
def _hint_strings(self, elems):
"""Calculate the hint strings for elems.
Inspired by Vimium.
Args:
elems: The elements to get hint strings for.
Return:
A list of hint strings, in the same order as the elements.
"""
if config.get('hints', 'mode') == 'number':
chars = '0123456789'
else:
chars = config.get('hints', 'chars')
# Determine how many digits the link hints will require in the worst
# case. Usually we do not need all of these digits for every link
# single hint, so we can show shorter hints for a few of the links.
needed = math.ceil(math.log(len(elems), len(chars)))
# Short hints are the number of hints we can possibly show which are
# (needed - 1) digits in length.
short_count = math.floor((len(chars) ** needed - len(elems)) /
len(chars))
long_count = len(elems) - short_count
strings = []
if needed > 1:
for i in range(short_count):
strings.append(self._number_to_hint_str(i, chars, needed - 1))
start = short_count * len(chars)
for i in range(start, start + long_count):
strings.append(self._number_to_hint_str(i, chars, needed))
return self._shuffle_hints(strings, len(chars))
def _shuffle_hints(self, hints, length):
"""Shuffle the given set of hints so that they're scattered.
Hints starting with the same character will be spread evenly throughout
the array.
Inspired by Vimium.
Args:
hints: A list of hint strings.
length: Length of the available charset.
Return:
A list of shuffled hint strings.
"""
buckets = [[] for i in range(length)]
for i, hint in enumerate(hints):
buckets[i % len(buckets)].append(hint)
result = []
for bucket in buckets:
result += bucket
return result
def _number_to_hint_str(self, number, chars, digits=0):
"""Convert a number like "8" into a hint string like "JK".
This is used to sequentially generate all of the hint text.
The hint string will be "padded with zeroes" to ensure its length is >=
digits.
Inspired by Vimium.
Args:
number: The hint number.
chars: The charset to use.
digits: The minimum output length.
Return:
A hint string.
"""
base = len(chars)
hintstr = []
remainder = 0
while True:
remainder = number % base
hintstr.insert(0, chars[remainder])
number -= remainder
number //= base
if number <= 0:
break
# Pad the hint string we're returning so that it matches digits.
for _ in range(0, digits - len(hintstr)):
hintstr.insert(0, chars[0])
return ''.join(hintstr)
def _draw_label(self, elem, string):
"""Draw a hint label over an element.
Args:
elem: The QWebElement to use.
string: The hint string to print.
Return:
The newly created label elment
"""
rect = elem.geometry()
css = self.HINT_CSS.format(left=rect.x(), top=rect.y(),
config=config.instance())
doc = self._frame.documentElement()
# It seems impossible to create an empty QWebElement for which isNull()
# is false so we can work with it.
# As a workaround, we use appendInside() with markup as argument, and
# then use lastChild() to get a reference to it.
# See: http://stackoverflow.com/q/7364852/2085149
doc.appendInside('<span class="qutehint" style="{}">{}</span>'.format(
css, string))
return doc.lastChild()
def _click(self, elem):
"""Click an element.
Args:
elem: The QWebElement to click.
"""
if self._target == Target.rapid:
target = Target.bgtab
else:
target = self._target
self.set_open_target.emit(Target[target])
point = elem.geometry().topLeft()
scrollpos = self._frame.scrollPosition()
logging.debug("Clicking on \"{}\" at {}/{} - {}/{}".format(
elem.toPlainText(), point.x(), point.y(), scrollpos.x(),
scrollpos.y()))
point -= scrollpos
events = [
QMouseEvent(QEvent.MouseMove, point, Qt.NoButton, Qt.NoButton,
Qt.NoModifier),
QMouseEvent(QEvent.MouseButtonPress, point, Qt.LeftButton,
Qt.NoButton, Qt.NoModifier),
QMouseEvent(QEvent.MouseButtonRelease, point, Qt.LeftButton,
Qt.NoButton, Qt.NoModifier),
]
for evt in events:
self.mouse_event.emit(evt)
def _yank(self, link):
"""Yank an element to the clipboard or primary selection.
Args:
link: The URL to open.
"""
sel = self._target == Target.yank_primary
mode = QClipboard.Selection if sel else QClipboard.Clipboard
QApplication.clipboard().setText(urlutils.urlstring(link), mode)
message.info("URL yanked to {}".format("primary selection" if sel
else "clipboard"))
def _preset_cmd_text(self, link):
"""Preset a commandline text based on a hint URL.
Args:
link: The link to open.
"""
commands = {
Target.cmd: 'open',
Target.cmd_tab: 'tabopen',
Target.cmd_bgtab: 'backtabopen',
}
message.set_cmd_text(':{} {}'.format(commands[self._target],
urlutils.urlstring(link)))
def _resolve_link(self, elem, baseurl=None):
"""Resolve a link and check if we want to keep it.
Args:
elem: The QWebElement to get the link of.
baseurl: The baseurl of the current tab (overrides self._baseurl).
Return:
A QUrl with the absolute link, or None.
"""
link = elem.attribute('href')
if not link:
return None
if baseurl is None:
baseurl = self._baseurl
link = urlutils.qurl(link)
if link.isRelative():
link = baseurl.resolved(link)
return link
def _find_prevnext(self, frame, prev=False):
"""Find a prev/next element in frame."""
# First check for <link rel="prev(ious)|next">
elems = frame.findAllElements(webelem.SELECTORS['prevnext_rel'])
rel_values = ['prev', 'previous'] if prev else ['next']
for e in elems:
if e.attribute('rel') in rel_values:
return e
# Then check for regular links
elems = frame.findAllElements(webelem.SELECTORS['prevnext'])
option = 'prev-regexes' if prev else 'next-regexes'
if not elems:
return None
for regex in config.get('hints', option):
for e in elems:
if regex.match(e.toPlainText()):
return e
return None
def follow_prevnext(self, frame, baseurl, prev=False, newtab=False):
"""Click a "previous"/"next" element on the page.
Args:
frame: The frame where the element is in.
baseurl: The base URL of the current tab.
prev: True to open a "previous" link, False to open a "next" link.
newtab: True to open in a new tab, False for the current tab.
"""
elem = self._find_prevnext(frame, prev)
if elem is None:
message.error("No {} links found!".format("prev" if prev
else "forward"))
return
link = self._resolve_link(elem, baseurl)
if link is None:
message.error("No {} links found!".format("prev" if prev
else "forward"))
return
self.openurl.emit(link, newtab)
def start(self, frame, baseurl, group=webelem.Group.all,
target=Target.normal):
"""Start hinting.
Args:
frame: The QWebFrame to place hints in.
baseurl: URL of the current page.
group: Which group of elements to hint.
target: What to do with the link. See attribute docstring.
Emit:
hint_strings_updated: Emitted to update keypraser.
"""
elems = frame.findAllElements(webelem.SELECTORS[group])
self._target = target
self._baseurl = baseurl
if frame is None:
# This should never happen since we check frame before calling
# start. But since we had a bug where frame is None in
# on_mode_left, we are extra careful here.
raise ValueError("start() was called with frame=None")
self._frame = frame
filterfunc = webelem.FILTERS.get(group, lambda e: True)
visible_elems = []
for e in elems:
if filterfunc(e) and webelem.is_visible(e, self._frame):
visible_elems.append(e)
if not visible_elems:
message.error("No elements found.")
return
texts = {
Target.normal: "Follow hint...",
Target.tab: "Follow hint in new tab...",
Target.bgtab: "Follow hint in background tab...",
Target.yank: "Yank hint to clipboard...",
Target.yank_primary: "Yank hint to primary selection...",
Target.cmd: "Set hint in commandline...",
Target.cmd_tab: "Set hint in commandline as new tab...",
Target.cmd_bgtab: "Set hint in commandline as background tab...",
Target.rapid: "Follow hint (rapid mode)...",
}
message.text(texts[target])
strings = self._hint_strings(visible_elems)
for e, string in zip(visible_elems, strings):
label = self._draw_label(e, string)
self._elems[string] = ElemTuple(e, label)
frame.contentsSizeChanged.connect(self.on_contents_size_changed)
self.hint_strings_updated.emit(strings)
modeman.enter('hint')
@pyqtSlot(str)
def handle_partial_key(self, keystr):
"""Handle a new partial keypress."""
delete = []
for (string, elems) in self._elems.items():
if string.startswith(keystr):
matched = string[:len(keystr)]
rest = string[len(keystr):]
elems.label.setInnerXml('<font color="{}">{}</font>{}'.format(
config.get('colors', 'hints.fg.match'), matched, rest))
else:
elems.label.removeFromDocument()
delete.append(string)
for key in delete:
del self._elems[key]
@pyqtSlot(str)
def filter_hints(self, filterstr):
"""Filter displayed hints according to a text."""
delete = []
for (string, elems) in self._elems.items():
if not elems.elem.toPlainText().lower().startswith(filterstr):
elems.label.removeFromDocument()
delete.append(string)
for key in delete:
del self._elems[key]
if not self._elems:
# Whoops, filtered all hints
modeman.leave('hint')
elif len(self._elems) == 1 and config.get('hints', 'auto-follow'):
# unpacking gets us the first (and only) key in the dict.
self.fire(*self._elems)
@pyqtSlot(str)
def fire(self, keystr, force=False):
"""Fire a completed hint.
Args:
keystr: The keychain string to follow.
force: When True, follow even when auto-follow is false.
"""
if not (force or config.get('hints', 'auto-follow')):
self.handle_partial_key(keystr)
self._to_follow = keystr
return
# Handlers which take a QWebElement
elem_handlers = {
Target.normal: self._click,
Target.tab: self._click,
Target.bgtab: self._click,
Target.rapid: self._click,
}
# Handlers which take a link string
link_handlers = {
Target.yank: self._yank,
Target.yank_primary: self._yank,
Target.cmd: self._preset_cmd_text,
Target.cmd_tab: self._preset_cmd_text,
Target.cmd_bgtab: self._preset_cmd_text,
}
elem = self._elems[keystr].elem
if self._target in elem_handlers:
elem_handlers[self._target](elem)
elif self._target in link_handlers:
link = self._resolve_link(elem)
if link is None:
message.error("No suitable link found for this element.")
return
link_handlers[self._target](link)
else:
raise ValueError("No suitable handler found!")
if self._target != Target.rapid:
modeman.leave('hint')
@cmdutils.register(instance='hintmanager', hide=True)
def follow_hint(self):
"""Follow the currently selected hint."""
if not self._to_follow:
message.error("No hint to follow")
self.fire(self._to_follow, force=True)
@pyqtSlot('QSize')
def on_contents_size_changed(self, _size):
"""Reposition hints if contents size changed."""
for elems in self._elems.values():
rect = elems.elem.geometry()
css = self.HINT_CSS.format(left=rect.x(), top=rect.y(),
config=config.instance())
elems.label.setAttribute('style', css)
@pyqtSlot(str)
def on_mode_left(self, mode):
"""Stop hinting when hinting mode was left."""
logging.warn("mode {} left".format(mode))
if mode != 'hint':
return
for elem in self._elems.values():
elem.label.removeFromDocument()
self._frame.contentsSizeChanged.disconnect(
self.on_contents_size_changed)
self._elems = {}
self._to_follow = None
self._target = None
self._frame = None
message.clear()