Current File : //snap/core20/2434/lib/python3/dist-packages/urwid/canvas.py
#!/usr/bin/python
#
# Urwid canvas class and functions
# Copyright (C) 2004-2011 Ian Ward
#
# This library is free software; you can redistribute it and/or
# modify it under the terms of the GNU Lesser General Public
# License as published by the Free Software Foundation; either
# version 2.1 of the License, or (at your option) any later version.
#
# This library 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
# Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public
# License along with this library; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
#
# Urwid web site: http://excess.org/urwid/
from __future__ import division, print_function
import weakref
from urwid.util import rle_len, rle_append_modify, rle_join_modify, rle_product, \
calc_width, calc_text_pos, apply_target_encoding, trim_text_attr_cs
from urwid.text_layout import trim_line, LayoutSegment
from urwid.compat import bytes
class CanvasCache(object):
"""
Cache for rendered canvases. Automatically populated and
accessed by Widget render() MetaClass magic, cleared by
Widget._invalidate().
Stores weakrefs to the canvas objects, so an external class
must maintain a reference for this cache to be effective.
At present the Screen classes store the last topmost canvas
after redrawing the screen, keeping the canvases from being
garbage collected.
_widgets[widget] = {(wcls, size, focus): weakref.ref(canvas), ...}
_refs[weakref.ref(canvas)] = (widget, wcls, size, focus)
_deps[widget} = [dependent_widget, ...]
"""
_widgets = {}
_refs = {}
_deps = {}
hits = 0
fetches = 0
cleanups = 0
def store(cls, wcls, canvas):
"""
Store a weakref to canvas in the cache.
wcls -- widget class that contains render() function
canvas -- rendered canvas with widget_info (widget, size, focus)
"""
if not canvas.cacheable:
return
assert canvas.widget_info, "Can't store canvas without widget_info"
widget, size, focus = canvas.widget_info
def walk_depends(canv):
"""
Collect all child widgets for determining who we
depend on.
"""
# FIXME: is this recursion necessary? The cache
# invalidating might work with only one level.
depends = []
for x, y, c, pos in canv.children:
if c.widget_info:
depends.append(c.widget_info[0])
elif hasattr(c, 'children'):
depends.extend(walk_depends(c))
return depends
# use explicit depends_on if available from the canvas
depends_on = getattr(canvas, 'depends_on', None)
if depends_on is None and hasattr(canvas, 'children'):
depends_on = walk_depends(canvas)
if depends_on:
for w in depends_on:
if w not in cls._widgets:
return
for w in depends_on:
cls._deps.setdefault(w,[]).append(widget)
ref = weakref.ref(canvas, cls.cleanup)
cls._refs[ref] = (widget, wcls, size, focus)
cls._widgets.setdefault(widget, {})[(wcls, size, focus)] = ref
store = classmethod(store)
def fetch(cls, widget, wcls, size, focus):
"""
Return the cached canvas or None.
widget -- widget object requested
wcls -- widget class that contains render() function
size, focus -- render() parameters
"""
cls.fetches += 1 # collect stats
sizes = cls._widgets.get(widget, None)
if not sizes:
return None
ref = sizes.get((wcls, size, focus), None)
if not ref:
return None
canv = ref()
if canv:
cls.hits += 1 # more stats
return canv
fetch = classmethod(fetch)
def invalidate(cls, widget):
"""
Remove all canvases cached for widget.
"""
try:
for ref in cls._widgets[widget].values():
try:
del cls._refs[ref]
except KeyError:
pass
del cls._widgets[widget]
except KeyError:
pass
if widget not in cls._deps:
return
dependants = cls._deps.get(widget, [])
try:
del cls._deps[widget]
except KeyError:
pass
for w in dependants:
cls.invalidate(w)
invalidate = classmethod(invalidate)
def cleanup(cls, ref):
cls.cleanups += 1 # collect stats
w = cls._refs.get(ref, None)
del cls._refs[ref]
if not w:
return
widget, wcls, size, focus = w
sizes = cls._widgets.get(widget, None)
if not sizes:
return
try:
del sizes[(wcls, size, focus)]
except KeyError:
pass
if not sizes:
try:
del cls._widgets[widget]
del cls._deps[widget]
except KeyError:
pass
cleanup = classmethod(cleanup)
def clear(cls):
"""
Empty the cache.
"""
cls._widgets = {}
cls._refs = {}
cls._deps = {}
clear = classmethod(clear)
class CanvasError(Exception):
pass
class Canvas(object):
"""
base class for canvases
"""
cacheable = True
_finalized_error = CanvasError("This canvas has been finalized. "
"Use CompositeCanvas to wrap this canvas if "
"you need to make changes.")
_renamed_error = CanvasError("The old Canvas class is now called "
"TextCanvas. Canvas is now the base class for all canvas "
"classes.")
_old_repr_error = CanvasError("The internal representation of "
"canvases is no longer stored as .text, .attr, and .cs "
"lists, please see the TextCanvas class for the new "
"representation of canvas content.")
def __init__(self, value1=None, value2=None, value3=None):
"""
value1, value2, value3 -- if not None, raise a helpful error:
the old Canvas class is now called TextCanvas.
"""
if value1 is not None:
raise self._renamed_error
self._widget_info = None
self.coords = {}
self.shortcuts = {}
def finalize(self, widget, size, focus):
"""
Mark this canvas as finalized (should not be any future
changes to its content). This is required before caching
the canvas. This happens automatically after a widget's
'render call returns the canvas thanks to some metaclass
magic.
widget -- widget that rendered this canvas
size -- size parameter passed to widget's render method
focus -- focus parameter passed to widget's render method
"""
if self.widget_info:
raise self._finalized_error
self._widget_info = widget, size, focus
def _get_widget_info(self):
return self._widget_info
widget_info = property(_get_widget_info)
def _raise_old_repr_error(self, val=None):
raise self._old_repr_error
def _text_content(self):
"""
Return the text content of the canvas as a list of strings,
one for each row.
"""
return [bytes().join([text for (attr, cs, text) in row])
for row in self.content()]
text = property(_text_content, _raise_old_repr_error)
attr = property(_raise_old_repr_error, _raise_old_repr_error)
cs = property(_raise_old_repr_error, _raise_old_repr_error)
def content(self, trim_left=0, trim_top=0, cols=None, rows=None,
attr=None):
raise NotImplementedError()
def cols(self):
raise NotImplementedError()
def rows(self):
raise NotImplementedError()
def content_delta(self):
raise NotImplementedError()
def get_cursor(self):
c = self.coords.get("cursor", None)
if not c:
return
return c[:2] # trim off data part
def set_cursor(self, c):
if self.widget_info and self.cacheable:
raise self._finalized_error
if c is None:
try:
del self.coords["cursor"]
except KeyError:
pass
return
self.coords["cursor"] = c + (None,) # data part
cursor = property(get_cursor, set_cursor)
def get_pop_up(self):
c = self.coords.get("pop up", None)
if not c:
return
return c
def set_pop_up(self, w, left, top, overlay_width, overlay_height):
"""
This method adds pop-up information to the canvas. This information
is intercepted by a PopUpTarget widget higher in the chain to
display a pop-up at the given (left, top) position relative to the
current canvas.
:param w: widget to use for the pop-up
:type w: widget
:param left: x position for left edge of pop-up >= 0
:type left: int
:param top: y position for top edge of pop-up >= 0
:type top: int
:param overlay_width: width of overlay in screen columns > 0
:type overlay_width: int
:param overlay_height: height of overlay in screen rows > 0
:type overlay_height: int
"""
if self.widget_info and self.cacheable:
raise self._finalized_error
self.coords["pop up"] = (left, top, (
w, overlay_width, overlay_height))
def translate_coords(self, dx, dy):
"""
Return coords shifted by (dx, dy).
"""
d = {}
for name, (x, y, data) in self.coords.items():
d[name] = (x+dx, y+dy, data)
return d
class TextCanvas(Canvas):
"""
class for storing rendered text and attributes
"""
def __init__(self, text=None, attr=None, cs=None,
cursor=None, maxcol=None, check_width=True):
"""
text -- list of strings, one for each line
attr -- list of run length encoded attributes for text
cs -- list of run length encoded character set for text
cursor -- (x,y) of cursor or None
maxcol -- screen columns taken by this canvas
check_width -- check and fix width of all lines in text
"""
Canvas.__init__(self)
if text == None:
text = []
if check_width:
widths = []
for t in text:
if type(t) != bytes:
raise CanvasError("Canvas text must be plain strings encoded in the screen's encoding", repr(text))
widths.append( calc_width( t, 0, len(t)) )
else:
assert type(maxcol) == int
widths = [maxcol] * len(text)
if maxcol is None:
if widths:
# find maxcol ourselves
maxcol = max(widths)
else:
maxcol = 0
if attr == None:
attr = [[] for x in range(len(text))]
if cs == None:
cs = [[] for x in range(len(text))]
# pad text and attr to maxcol
for i in range(len(text)):
w = widths[i]
if w > maxcol:
raise CanvasError("Canvas text is wider than the maxcol specified \n%r\n%r\n%r"%(maxcol,widths,text))
if w < maxcol:
text[i] = text[i] + bytes().rjust(maxcol-w)
a_gap = len(text[i]) - rle_len( attr[i] )
if a_gap < 0:
raise CanvasError("Attribute extends beyond text \n%r\n%r" % (text[i],attr[i]) )
if a_gap:
rle_append_modify( attr[i], (None, a_gap))
cs_gap = len(text[i]) - rle_len( cs[i] )
if cs_gap < 0:
raise CanvasError("Character Set extends beyond text \n%r\n%r" % (text[i],cs[i]) )
if cs_gap:
rle_append_modify( cs[i], (None, cs_gap))
self._attr = attr
self._cs = cs
self.cursor = cursor
self._text = text
self._maxcol = maxcol
def rows(self):
"""Return the number of rows in this canvas."""
rows = len(self._text)
assert isinstance(rows, int)
return rows
def cols(self):
"""Return the screen column width of this canvas."""
return self._maxcol
def translated_coords(self,dx,dy):
"""
Return cursor coords shifted by (dx, dy), or None if there
is no cursor.
"""
if self.cursor:
x, y = self.cursor
return x+dx, y+dy
return None
def content(self, trim_left=0, trim_top=0, cols=None, rows=None,
attr_map=None):
"""
Return the canvas content as a list of rows where each row
is a list of (attr, cs, text) tuples.
trim_left, trim_top, cols, rows may be set by
CompositeCanvas when rendering a partially obscured
canvas.
"""
maxcol, maxrow = self.cols(), self.rows()
if not cols:
cols = maxcol - trim_left
if not rows:
rows = maxrow - trim_top
assert trim_left >= 0 and trim_left < maxcol
assert cols > 0 and trim_left + cols <= maxcol
assert trim_top >=0 and trim_top < maxrow
assert rows > 0 and trim_top + rows <= maxrow
if trim_top or rows < maxrow:
text_attr_cs = zip(
self._text[trim_top:trim_top+rows],
self._attr[trim_top:trim_top+rows],
self._cs[trim_top:trim_top+rows])
else:
text_attr_cs = zip(self._text, self._attr, self._cs)
for text, a_row, cs_row in text_attr_cs:
if trim_left or cols < self._maxcol:
text, a_row, cs_row = trim_text_attr_cs(
text, a_row, cs_row, trim_left,
trim_left + cols)
attr_cs = rle_product(a_row, cs_row)
i = 0
row = []
for (a, cs), run in attr_cs:
if attr_map and a in attr_map:
a = attr_map[a]
row.append((a, cs, text[i:i+run]))
i += run
yield row
def content_delta(self, other):
"""
Return the differences between other and this canvas.
If other is the same object as self this will return no
differences, otherwise this is the same as calling
content().
"""
if other is self:
return [self.cols()]*self.rows()
return self.content()
class BlankCanvas(Canvas):
"""
a canvas with nothing on it, only works as part of a composite canvas
since it doesn't know its own size
"""
def __init__(self):
Canvas.__init__(self, None)
def content(self, trim_left, trim_top, cols, rows, attr):
"""
return (cols, rows) of spaces with default attributes.
"""
def_attr = None
if attr and None in attr:
def_attr = attr[None]
line = [(def_attr, None, bytes().rjust(cols))]
for i in range(rows):
yield line
def cols(self):
raise NotImplementedError("BlankCanvas doesn't know its own size!")
def rows(self):
raise NotImplementedError("BlankCanvas doesn't know its own size!")
def content_delta(self):
raise NotImplementedError("BlankCanvas doesn't know its own size!")
blank_canvas = BlankCanvas()
class SolidCanvas(Canvas):
"""
A canvas filled completely with a single character.
"""
def __init__(self, fill_char, cols, rows):
Canvas.__init__(self)
end, col = calc_text_pos(fill_char, 0, len(fill_char), 1)
assert col == 1, "Invalid fill_char: %r" % fill_char
self._text, cs = apply_target_encoding(fill_char[:end])
self._cs = cs[0][0]
self.size = cols, rows
self.cursor = None
def cols(self):
return self.size[0]
def rows(self):
return self.size[1]
def content(self, trim_left=0, trim_top=0, cols=None, rows=None,
attr=None):
if cols is None:
cols = self.size[0]
if rows is None:
rows = self.size[1]
def_attr = None
if attr and None in attr:
def_attr = attr[None]
line = [(def_attr, self._cs, self._text*cols)]
for i in range(rows):
yield line
def content_delta(self, other):
"""
Return the differences between other and this canvas.
"""
if other is self:
return [self.cols()]*self.rows()
return self.content()
class CompositeCanvas(Canvas):
"""
class for storing a combination of canvases
"""
def __init__(self, canv=None):
"""
canv -- a Canvas object to wrap this CompositeCanvas around.
if canv is a CompositeCanvas, make a copy of its contents
"""
# a "shard" is a (num_rows, list of cviews) tuple, one for
# each cview starting in this shard
# a "cview" is a tuple that defines a view of a canvas:
# (trim_left, trim_top, cols, rows, attr_map, canv)
# a "shard tail" is a list of tuples:
# (col_gap, done_rows, content_iter, cview)
# tuples that define the unfinished cviews that are part of
# shards following the first shard.
Canvas.__init__(self)
if canv is None:
self.shards = []
self.children = []
else:
if hasattr(canv, "shards"):
self.shards = canv.shards
else:
self.shards = [(canv.rows(), [
(0, 0, canv.cols(), canv.rows(),
None, canv)])]
self.children = [(0, 0, canv, None)]
self.coords.update(canv.coords)
for shortcut in canv.shortcuts:
self.shortcuts[shortcut] = "wrap"
def rows(self):
for r,cv in self.shards:
try:
assert isinstance(r, int)
except AssertionError:
raise AssertionError(r, cv)
rows = sum([r for r,cv in self.shards])
assert isinstance(rows, int)
return rows
def cols(self):
if not self.shards:
return 0
cols = sum([cv[2] for cv in self.shards[0][1]])
assert isinstance(cols, int)
return cols
def content(self):
"""
Return the canvas content as a list of rows where each row
is a list of (attr, cs, text) tuples.
"""
shard_tail = []
for num_rows, cviews in self.shards:
# combine shard and shard tail
sbody = shard_body(cviews, shard_tail)
# output rows
for i in range(num_rows):
yield shard_body_row(sbody)
# prepare next shard tail
shard_tail = shard_body_tail(num_rows, sbody)
def content_delta(self, other):
"""
Return the differences between other and this canvas.
"""
if not hasattr(other, 'shards'):
for row in self.content():
yield row
return
shard_tail = []
for num_rows, cviews in shards_delta(
self.shards, other.shards):
# combine shard and shard tail
sbody = shard_body(cviews, shard_tail)
# output rows
row = []
for i in range(num_rows):
# if whole shard is unchanged, don't keep
# calling shard_body_row
if len(row) != 1 or type(row[0]) != int:
row = shard_body_row(sbody)
yield row
# prepare next shard tail
shard_tail = shard_body_tail(num_rows, sbody)
def trim(self, top, count=None):
"""Trim lines from the top and/or bottom of canvas.
top -- number of lines to remove from top
count -- number of lines to keep, or None for all the rest
"""
assert top >= 0, "invalid trim amount %d!"%top
assert top < self.rows(), "cannot trim %d lines from %d!"%(
top, self.rows())
if self.widget_info:
raise self._finalized_error
if top:
self.shards = shards_trim_top(self.shards, top)
if count == 0:
self.shards = []
elif count is not None:
self.shards = shards_trim_rows(self.shards, count)
self.coords = self.translate_coords(0, -top)
def trim_end(self, end):
"""Trim lines from the bottom of the canvas.
end -- number of lines to remove from the end
"""
assert end > 0, "invalid trim amount %d!"%end
assert end <= self.rows(), "cannot trim %d lines from %d!"%(
end, self.rows())
if self.widget_info:
raise self._finalized_error
self.shards = shards_trim_rows(self.shards, self.rows() - end)
def pad_trim_left_right(self, left, right):
"""
Pad or trim this canvas on the left and right
values > 0 indicate screen columns to pad
values < 0 indicate screen columns to trim
"""
if self.widget_info:
raise self._finalized_error
shards = self.shards
if left < 0 or right < 0:
trim_left = max(0, -left)
cols = self.cols() - trim_left - max(0, -right)
shards = shards_trim_sides(shards, trim_left, cols)
rows = self.rows()
if left > 0 or right > 0:
top_rows, top_cviews = shards[0]
if left > 0:
new_top_cviews = (
[(0,0,left,rows,None,blank_canvas)] +
top_cviews)
else:
new_top_cviews = top_cviews[:] #copy
if right > 0:
new_top_cviews.append(
(0,0,right,rows,None,blank_canvas))
shards = [(top_rows, new_top_cviews)] + shards[1:]
self.coords = self.translate_coords(left, 0)
self.shards = shards
def pad_trim_top_bottom(self, top, bottom):
"""
Pad or trim this canvas on the top and bottom.
"""
if self.widget_info:
raise self._finalized_error
orig_shards = self.shards
if top < 0 or bottom < 0:
trim_top = max(0, -top)
rows = self.rows() - trim_top - max(0, -bottom)
self.trim(trim_top, rows)
cols = self.cols()
if top > 0:
self.shards = [(top,
[(0,0,cols,top,None,blank_canvas)])] + \
self.shards
self.coords = self.translate_coords(0, top)
if bottom > 0:
if orig_shards is self.shards:
self.shards = self.shards[:]
self.shards.append((bottom,
[(0,0,cols,bottom,None,blank_canvas)]))
def overlay(self, other, left, top ):
"""Overlay other onto this canvas."""
if self.widget_info:
raise self._finalized_error
width = other.cols()
height = other.rows()
right = self.cols() - left - width
bottom = self.rows() - top - height
assert right >= 0, "top canvas of overlay not the size expected!" + repr((other.cols(),left,right,width))
assert bottom >= 0, "top canvas of overlay not the size expected!" + repr((other.rows(),top,bottom,height))
shards = self.shards
top_shards = []
side_shards = self.shards
bottom_shards = []
if top:
side_shards = shards_trim_top(shards, top)
top_shards = shards_trim_rows(shards, top)
if bottom:
bottom_shards = shards_trim_top(side_shards, height)
side_shards = shards_trim_rows(side_shards, height)
left_shards = []
right_shards = []
if left > 0:
left_shards = [shards_trim_sides(side_shards, 0, left)]
if right > 0:
right_shards = [shards_trim_sides(side_shards,
max(0, left + width), right)]
if not self.rows():
middle_shards = []
elif left or right:
middle_shards = shards_join(left_shards +
[other.shards] + right_shards)
else:
middle_shards = other.shards
self.shards = top_shards + middle_shards + bottom_shards
self.coords.update(other.translate_coords(left, top))
def fill_attr(self, a):
"""
Apply attribute a to all areas of this canvas with default
attribute currently set to None, leaving other attributes
intact."""
self.fill_attr_apply({None:a})
def fill_attr_apply(self, mapping):
"""
Apply an attribute-mapping dictionary to the canvas.
mapping -- dictionary of original-attribute:new-attribute items
"""
if self.widget_info:
raise self._finalized_error
shards = []
for num_rows, original_cviews in self.shards:
new_cviews = []
for cv in original_cviews:
# cv[4] == attr_map
if cv[4] is None:
new_cviews.append(cv[:4] +
(mapping,) + cv[5:])
else:
combined = dict(mapping)
combined.update([
(k, mapping.get(v, v)) for k,v in cv[4].items()])
new_cviews.append(cv[:4] +
(combined,) + cv[5:])
shards.append((num_rows, new_cviews))
self.shards = shards
def set_depends(self, widget_list):
"""
Explicitly specify the list of widgets that this canvas
depends on. If any of these widgets change this canvas
will have to be updated.
"""
if self.widget_info:
raise self._finalized_error
self.depends_on = widget_list
def shard_body_row(sbody):
"""
Return one row, advancing the iterators in sbody.
** MODIFIES sbody by calling next() on its iterators **
"""
row = []
for done_rows, content_iter, cview in sbody:
if content_iter:
row.extend(next(content_iter))
else:
# need to skip this unchanged canvas
if row and type(row[-1]) == int:
row[-1] = row[-1] + cview[2]
else:
row.append(cview[2])
return row
def shard_body_tail(num_rows, sbody):
"""
Return a new shard tail that follows this shard body.
"""
shard_tail = []
col_gap = 0
done_rows = 0
for done_rows, content_iter, cview in sbody:
cols, rows = cview[2:4]
done_rows += num_rows
if done_rows == rows:
col_gap += cols
continue
shard_tail.append((col_gap, done_rows, content_iter, cview))
col_gap = 0
return shard_tail
def shards_delta(shards, other_shards):
"""
Yield shards1 with cviews that are the same as shards2
having canv = None.
"""
other_shards_iter = iter(other_shards)
other_num_rows = other_cviews = None
done = other_done = 0
for num_rows, cviews in shards:
if other_num_rows is None:
other_num_rows, other_cviews = next(other_shards_iter)
while other_done < done:
other_done += other_num_rows
other_num_rows, other_cviews = next(other_shards_iter)
if other_done > done:
yield (num_rows, cviews)
done += num_rows
continue
# top-aligned shards, compare each cview
yield (num_rows, shard_cviews_delta(cviews, other_cviews))
other_done += other_num_rows
other_num_rows = None
done += num_rows
def shard_cviews_delta(cviews, other_cviews):
"""
"""
other_cviews_iter = iter(other_cviews)
other_cv = None
cols = other_cols = 0
for cv in cviews:
if other_cv is None:
other_cv = next(other_cviews_iter)
while other_cols < cols:
other_cols += other_cv[2]
other_cv = next(other_cviews_iter)
if other_cols > cols:
yield cv
cols += cv[2]
continue
# top-left-aligned cviews, compare them
if cv[5] is other_cv[5] and cv[:5] == other_cv[:5]:
yield cv[:5]+(None,)+cv[6:]
else:
yield cv
other_cols += other_cv[2]
other_cv = None
cols += cv[2]
def shard_body(cviews, shard_tail, create_iter=True, iter_default=None):
"""
Return a list of (done_rows, content_iter, cview) tuples for
this shard and shard tail.
If a canvas in cviews is None (eg. when unchanged from
shard_cviews_delta()) or if create_iter is False then no
iterator is created for content_iter.
iter_default is the value used for content_iter when no iterator
is created.
"""
col = 0
body = [] # build the next shard tail
cviews_iter = iter(cviews)
for col_gap, done_rows, content_iter, tail_cview in shard_tail:
while col_gap:
try:
cview = next(cviews_iter)
except StopIteration:
raise CanvasError("cviews do not fill gaps in"
" shard_tail!")
(trim_left, trim_top, cols, rows, attr_map, canv) = \
cview[:6]
col += cols
col_gap -= cols
if col_gap < 0:
raise CanvasError("cviews overflow gaps in"
" shard_tail!")
if create_iter and canv:
new_iter = canv.content(trim_left, trim_top,
cols, rows, attr_map)
else:
new_iter = iter_default
body.append((0, new_iter, cview))
body.append((done_rows, content_iter, tail_cview))
for cview in cviews_iter:
(trim_left, trim_top, cols, rows, attr_map, canv) = \
cview[:6]
if create_iter and canv:
new_iter = canv.content(trim_left, trim_top, cols, rows,
attr_map)
else:
new_iter = iter_default
body.append((0, new_iter, cview))
return body
def shards_trim_top(shards, top):
"""
Return shards with top rows removed.
"""
assert top > 0
shard_iter = iter(shards)
shard_tail = []
# skip over shards that are completely removed
for num_rows, cviews in shard_iter:
if top < num_rows:
break
sbody = shard_body(cviews, shard_tail, False)
shard_tail = shard_body_tail(num_rows, sbody)
top -= num_rows
else:
raise CanvasError("tried to trim shards out of existence")
sbody = shard_body(cviews, shard_tail, False)
shard_tail = shard_body_tail(num_rows, sbody)
# trim the top of this shard
new_sbody = []
for done_rows, content_iter, cv in sbody:
new_sbody.append((0, content_iter,
cview_trim_top(cv, done_rows+top)))
sbody = new_sbody
new_shards = [(num_rows-top,
[cv for done_rows, content_iter, cv in sbody])]
# write out the rest of the shards
new_shards.extend(shard_iter)
return new_shards
def shards_trim_rows(shards, keep_rows):
"""
Return the topmost keep_rows rows from shards.
"""
assert keep_rows >= 0, keep_rows
new_shards = []
done_rows = 0
for num_rows, cviews in shards:
if done_rows >= keep_rows:
break
new_cviews = []
for cv in cviews:
if cv[3] + done_rows > keep_rows:
new_cviews.append(cview_trim_rows(cv,
keep_rows - done_rows))
else:
new_cviews.append(cv)
if num_rows + done_rows > keep_rows:
new_shards.append((keep_rows - done_rows, new_cviews))
else:
new_shards.append((num_rows, new_cviews))
done_rows += num_rows
return new_shards
def shards_trim_sides(shards, left, cols):
"""
Return shards with starting from column left and cols total width.
"""
assert left >= 0 and cols > 0, (left, cols)
shard_tail = []
new_shards = []
right = left + cols
for num_rows, cviews in shards:
sbody = shard_body(cviews, shard_tail, False)
shard_tail = shard_body_tail(num_rows, sbody)
new_cviews = []
col = 0
for done_rows, content_iter, cv in sbody:
cv_cols = cv[2]
next_col = col + cv_cols
if done_rows or next_col <= left or col >= right:
col = next_col
continue
if col < left:
cv = cview_trim_left(cv, left - col)
col = left
if next_col > right:
cv = cview_trim_cols(cv, right - col)
new_cviews.append(cv)
col = next_col
if not new_cviews:
prev_num_rows, prev_cviews = new_shards[-1]
new_shards[-1] = (prev_num_rows+num_rows, prev_cviews)
else:
new_shards.append((num_rows, new_cviews))
return new_shards
def shards_join(shard_lists):
"""
Return the result of joining shard lists horizontally.
All shards lists must have the same number of rows.
"""
shards_iters = [iter(sl) for sl in shard_lists]
shards_current = [next(i) for i in shards_iters]
new_shards = []
while True:
new_cviews = []
num_rows = min([r for r,cv in shards_current])
shards_next = []
for rows, cviews in shards_current:
if cviews:
new_cviews.extend(cviews)
shards_next.append((rows - num_rows, None))
shards_current = shards_next
new_shards.append((num_rows, new_cviews))
# advance to next shards
try:
for i in range(len(shards_current)):
if shards_current[i][0] > 0:
continue
shards_current[i] = next(shards_iters[i])
except StopIteration:
break
return new_shards
def cview_trim_rows(cv, rows):
return cv[:3] + (rows,) + cv[4:]
def cview_trim_top(cv, trim):
return (cv[0], trim + cv[1], cv[2], cv[3] - trim) + cv[4:]
def cview_trim_left(cv, trim):
return (cv[0] + trim, cv[1], cv[2] - trim,) + cv[3:]
def cview_trim_cols(cv, cols):
return cv[:2] + (cols,) + cv[3:]
def CanvasCombine(l):
"""Stack canvases in l vertically and return resulting canvas.
:param l: list of (canvas, position, focus) tuples:
position
a value that widget.set_focus will accept or None if not
allowed
focus
True if this canvas is the one that would be in focus
if the whole widget is in focus
"""
clist = [(CompositeCanvas(c),p,f) for c,p,f in l]
combined_canvas = CompositeCanvas()
shards = []
children = []
row = 0
focus_index = 0
n = 0
for canv, pos, focus in clist:
if focus:
focus_index = n
children.append((0, row, canv, pos))
shards.extend(canv.shards)
combined_canvas.coords.update(canv.translate_coords(0, row))
for shortcut in canv.shortcuts.keys():
combined_canvas.shortcuts[shortcut] = pos
row += canv.rows()
n += 1
if focus_index:
children = [children[focus_index]] + children[:focus_index] + \
children[focus_index+1:]
combined_canvas.shards = shards
combined_canvas.children = children
return combined_canvas
def CanvasOverlay(top_c, bottom_c, left, top):
"""
Overlay canvas top_c onto bottom_c at position (left, top).
"""
overlayed_canvas = CompositeCanvas(bottom_c)
overlayed_canvas.overlay(top_c, left, top)
overlayed_canvas.children = [(left, top, top_c, None),
(0, 0, bottom_c, None)]
overlayed_canvas.shortcuts = {} # disable background shortcuts
for shortcut in top_c.shortcuts.keys():
overlayed_canvas.shortcuts[shortcut]="fg"
return overlayed_canvas
def CanvasJoin(l):
"""
Join canvases in l horizontally. Return result.
:param l: list of (canvas, position, focus, cols) tuples:
position
value that widget.set_focus will accept or None if not allowed
focus
True if this canvas is the one that would be in focus if
the whole widget is in focus
cols
is the number of screen columns that this widget will require,
if larger than the actual canvas.cols() value then this widget
will be padded on the right.
"""
l2 = []
focus_item = 0
maxrow = 0
n = 0
for canv, pos, focus, cols in l:
rows = canv.rows()
pad_right = cols - canv.cols()
if focus:
focus_item = n
if rows > maxrow:
maxrow = rows
l2.append((canv, pos, pad_right, rows))
n += 1
shard_lists = []
children = []
joined_canvas = CompositeCanvas()
col = 0
for canv, pos, pad_right, rows in l2:
canv = CompositeCanvas(canv)
if pad_right:
canv.pad_trim_left_right(0, pad_right)
if rows < maxrow:
canv.pad_trim_top_bottom(0, maxrow - rows)
joined_canvas.coords.update(canv.translate_coords(col, 0))
for shortcut in canv.shortcuts.keys():
joined_canvas.shortcuts[shortcut] = pos
shard_lists.append(canv.shards)
children.append((col, 0, canv, pos))
col += canv.cols()
if focus_item:
children = [children[focus_item]] + children[:focus_item] + \
children[focus_item+1:]
joined_canvas.shards = shards_join(shard_lists)
joined_canvas.children = children
return joined_canvas
def apply_text_layout(text, attr, ls, maxcol):
t = []
a = []
c = []
class AttrWalk:
pass
aw = AttrWalk
aw.k = 0 # counter for moving through elements of a
aw.off = 0 # current offset into text of attr[ak]
def arange( start_offs, end_offs ):
"""Return an attribute list for the range of text specified."""
if start_offs < aw.off:
aw.k = 0
aw.off = 0
o = []
while aw.off < end_offs:
if len(attr)<=aw.k:
# run out of attributes
o.append((None,end_offs-max(start_offs,aw.off)))
break
at,run = attr[aw.k]
if aw.off+run <= start_offs:
# move forward through attr to find start_offs
aw.k += 1
aw.off += run
continue
if end_offs <= aw.off+run:
o.append((at, end_offs-max(start_offs,aw.off)))
break
o.append((at, aw.off+run-max(start_offs, aw.off)))
aw.k += 1
aw.off += run
return o
for line_layout in ls:
# trim the line to fit within maxcol
line_layout = trim_line( line_layout, text, 0, maxcol )
line = []
linea = []
linec = []
def attrrange( start_offs, end_offs, destw ):
"""
Add attributes based on attributes between
start_offs and end_offs.
"""
if start_offs == end_offs:
[(at,run)] = arange(start_offs,end_offs)
rle_append_modify( linea, ( at, destw ))
return
if destw == end_offs-start_offs:
for at, run in arange(start_offs,end_offs):
rle_append_modify( linea, ( at, run ))
return
# encoded version has different width
o = start_offs
for at, run in arange(start_offs, end_offs):
if o+run == end_offs:
rle_append_modify( linea, ( at, destw ))
return
tseg = text[o:o+run]
tseg, cs = apply_target_encoding( tseg )
segw = rle_len(cs)
rle_append_modify( linea, ( at, segw ))
o += run
destw -= segw
for seg in line_layout:
#if seg is None: assert 0, ls
s = LayoutSegment(seg)
if s.end:
tseg, cs = apply_target_encoding(
text[s.offs:s.end])
line.append(tseg)
attrrange(s.offs, s.end, rle_len(cs))
rle_join_modify( linec, cs )
elif s.text:
tseg, cs = apply_target_encoding( s.text )
line.append(tseg)
attrrange( s.offs, s.offs, len(tseg) )
rle_join_modify( linec, cs )
elif s.offs:
if s.sc:
line.append(bytes().rjust(s.sc))
attrrange( s.offs, s.offs, s.sc )
else:
line.append(bytes().rjust(s.sc))
linea.append((None, s.sc))
linec.append((None, s.sc))
t.append(bytes().join(line))
a.append(linea)
c.append(linec)
return TextCanvas(t, a, c, maxcol=maxcol)
Mini Shell