mirror of
https://github.com/microsoft/PowerToys.git
synced 2024-12-14 19:49:15 +08:00
189 lines
7.2 KiB
Python
189 lines
7.2 KiB
Python
|
"""Simple textbox editing widget with Emacs-like keybindings."""
|
||
|
|
||
|
import curses
|
||
|
import curses.ascii
|
||
|
|
||
|
def rectangle(win, uly, ulx, lry, lrx):
|
||
|
"""Draw a rectangle with corners at the provided upper-left
|
||
|
and lower-right coordinates.
|
||
|
"""
|
||
|
win.vline(uly+1, ulx, curses.ACS_VLINE, lry - uly - 1)
|
||
|
win.hline(uly, ulx+1, curses.ACS_HLINE, lrx - ulx - 1)
|
||
|
win.hline(lry, ulx+1, curses.ACS_HLINE, lrx - ulx - 1)
|
||
|
win.vline(uly+1, lrx, curses.ACS_VLINE, lry - uly - 1)
|
||
|
win.addch(uly, ulx, curses.ACS_ULCORNER)
|
||
|
win.addch(uly, lrx, curses.ACS_URCORNER)
|
||
|
win.addch(lry, lrx, curses.ACS_LRCORNER)
|
||
|
win.addch(lry, ulx, curses.ACS_LLCORNER)
|
||
|
|
||
|
class Textbox:
|
||
|
"""Editing widget using the interior of a window object.
|
||
|
Supports the following Emacs-like key bindings:
|
||
|
|
||
|
Ctrl-A Go to left edge of window.
|
||
|
Ctrl-B Cursor left, wrapping to previous line if appropriate.
|
||
|
Ctrl-D Delete character under cursor.
|
||
|
Ctrl-E Go to right edge (stripspaces off) or end of line (stripspaces on).
|
||
|
Ctrl-F Cursor right, wrapping to next line when appropriate.
|
||
|
Ctrl-G Terminate, returning the window contents.
|
||
|
Ctrl-H Delete character backward.
|
||
|
Ctrl-J Terminate if the window is 1 line, otherwise insert newline.
|
||
|
Ctrl-K If line is blank, delete it, otherwise clear to end of line.
|
||
|
Ctrl-L Refresh screen.
|
||
|
Ctrl-N Cursor down; move down one line.
|
||
|
Ctrl-O Insert a blank line at cursor location.
|
||
|
Ctrl-P Cursor up; move up one line.
|
||
|
|
||
|
Move operations do nothing if the cursor is at an edge where the movement
|
||
|
is not possible. The following synonyms are supported where possible:
|
||
|
|
||
|
KEY_LEFT = Ctrl-B, KEY_RIGHT = Ctrl-F, KEY_UP = Ctrl-P, KEY_DOWN = Ctrl-N
|
||
|
KEY_BACKSPACE = Ctrl-h
|
||
|
"""
|
||
|
def __init__(self, win, insert_mode=False):
|
||
|
self.win = win
|
||
|
self.insert_mode = insert_mode
|
||
|
(self.maxy, self.maxx) = win.getmaxyx()
|
||
|
self.maxy = self.maxy - 1
|
||
|
self.maxx = self.maxx - 1
|
||
|
self.stripspaces = 1
|
||
|
self.lastcmd = None
|
||
|
win.keypad(1)
|
||
|
|
||
|
def _end_of_line(self, y):
|
||
|
"""Go to the location of the first blank on the given line,
|
||
|
returning the index of the last non-blank character."""
|
||
|
last = self.maxx
|
||
|
while True:
|
||
|
if curses.ascii.ascii(self.win.inch(y, last)) != curses.ascii.SP:
|
||
|
last = min(self.maxx, last+1)
|
||
|
break
|
||
|
elif last == 0:
|
||
|
break
|
||
|
last = last - 1
|
||
|
return last
|
||
|
|
||
|
def _insert_printable_char(self, ch):
|
||
|
(y, x) = self.win.getyx()
|
||
|
if y < self.maxy or x < self.maxx:
|
||
|
if self.insert_mode:
|
||
|
oldch = self.win.inch()
|
||
|
# The try-catch ignores the error we trigger from some curses
|
||
|
# versions by trying to write into the lowest-rightmost spot
|
||
|
# in the window.
|
||
|
try:
|
||
|
self.win.addch(ch)
|
||
|
except curses.error:
|
||
|
pass
|
||
|
if self.insert_mode:
|
||
|
(backy, backx) = self.win.getyx()
|
||
|
if curses.ascii.isprint(oldch):
|
||
|
self._insert_printable_char(oldch)
|
||
|
self.win.move(backy, backx)
|
||
|
|
||
|
def do_command(self, ch):
|
||
|
"Process a single editing command."
|
||
|
(y, x) = self.win.getyx()
|
||
|
self.lastcmd = ch
|
||
|
if curses.ascii.isprint(ch):
|
||
|
if y < self.maxy or x < self.maxx:
|
||
|
self._insert_printable_char(ch)
|
||
|
elif ch == curses.ascii.SOH: # ^a
|
||
|
self.win.move(y, 0)
|
||
|
elif ch in (curses.ascii.STX,curses.KEY_LEFT, curses.ascii.BS,curses.KEY_BACKSPACE):
|
||
|
if x > 0:
|
||
|
self.win.move(y, x-1)
|
||
|
elif y == 0:
|
||
|
pass
|
||
|
elif self.stripspaces:
|
||
|
self.win.move(y-1, self._end_of_line(y-1))
|
||
|
else:
|
||
|
self.win.move(y-1, self.maxx)
|
||
|
if ch in (curses.ascii.BS, curses.KEY_BACKSPACE):
|
||
|
self.win.delch()
|
||
|
elif ch == curses.ascii.EOT: # ^d
|
||
|
self.win.delch()
|
||
|
elif ch == curses.ascii.ENQ: # ^e
|
||
|
if self.stripspaces:
|
||
|
self.win.move(y, self._end_of_line(y))
|
||
|
else:
|
||
|
self.win.move(y, self.maxx)
|
||
|
elif ch in (curses.ascii.ACK, curses.KEY_RIGHT): # ^f
|
||
|
if x < self.maxx:
|
||
|
self.win.move(y, x+1)
|
||
|
elif y == self.maxy:
|
||
|
pass
|
||
|
else:
|
||
|
self.win.move(y+1, 0)
|
||
|
elif ch == curses.ascii.BEL: # ^g
|
||
|
return 0
|
||
|
elif ch == curses.ascii.NL: # ^j
|
||
|
if self.maxy == 0:
|
||
|
return 0
|
||
|
elif y < self.maxy:
|
||
|
self.win.move(y+1, 0)
|
||
|
elif ch == curses.ascii.VT: # ^k
|
||
|
if x == 0 and self._end_of_line(y) == 0:
|
||
|
self.win.deleteln()
|
||
|
else:
|
||
|
# first undo the effect of self._end_of_line
|
||
|
self.win.move(y, x)
|
||
|
self.win.clrtoeol()
|
||
|
elif ch == curses.ascii.FF: # ^l
|
||
|
self.win.refresh()
|
||
|
elif ch in (curses.ascii.SO, curses.KEY_DOWN): # ^n
|
||
|
if y < self.maxy:
|
||
|
self.win.move(y+1, x)
|
||
|
if x > self._end_of_line(y+1):
|
||
|
self.win.move(y+1, self._end_of_line(y+1))
|
||
|
elif ch == curses.ascii.SI: # ^o
|
||
|
self.win.insertln()
|
||
|
elif ch in (curses.ascii.DLE, curses.KEY_UP): # ^p
|
||
|
if y > 0:
|
||
|
self.win.move(y-1, x)
|
||
|
if x > self._end_of_line(y-1):
|
||
|
self.win.move(y-1, self._end_of_line(y-1))
|
||
|
return 1
|
||
|
|
||
|
def gather(self):
|
||
|
"Collect and return the contents of the window."
|
||
|
result = ""
|
||
|
for y in range(self.maxy+1):
|
||
|
self.win.move(y, 0)
|
||
|
stop = self._end_of_line(y)
|
||
|
if stop == 0 and self.stripspaces:
|
||
|
continue
|
||
|
for x in range(self.maxx+1):
|
||
|
if self.stripspaces and x > stop:
|
||
|
break
|
||
|
result = result + chr(curses.ascii.ascii(self.win.inch(y, x)))
|
||
|
if self.maxy > 0:
|
||
|
result = result + "\n"
|
||
|
return result
|
||
|
|
||
|
def edit(self, validate=None):
|
||
|
"Edit in the widget window and collect the results."
|
||
|
while 1:
|
||
|
ch = self.win.getch()
|
||
|
if validate:
|
||
|
ch = validate(ch)
|
||
|
if not ch:
|
||
|
continue
|
||
|
if not self.do_command(ch):
|
||
|
break
|
||
|
self.win.refresh()
|
||
|
return self.gather()
|
||
|
|
||
|
if __name__ == '__main__':
|
||
|
def test_editbox(stdscr):
|
||
|
ncols, nlines = 9, 4
|
||
|
uly, ulx = 15, 20
|
||
|
stdscr.addstr(uly-2, ulx, "Use Ctrl-G to end editing.")
|
||
|
win = curses.newwin(nlines, ncols, uly, ulx)
|
||
|
rectangle(stdscr, uly-1, ulx-1, uly + nlines, ulx + ncols)
|
||
|
stdscr.refresh()
|
||
|
return Textbox(win).edit()
|
||
|
|
||
|
str = curses.wrapper(test_editbox)
|
||
|
print 'Contents of text box:', repr(str)
|