#!/usr/bin/env python
# -*- coding:utf-8 -*-
""" gtk textbuffer with undo functionality """
#Copyright (C) 2009 Florian Heinle
#
# 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
#----------------------------------------------------------------------
# 2010-04-27 James Paige - Add dummy fallbacks for some other pygtksourceview
# classes and methods
#
# 2010-03-19 James Paige - Fixed a bug in the .undo method where the
# stop iterator was invalid when undoing a
# deletion
import gtk
class UndoableInsert(object):
"""something that has been inserted into our textbuffer"""
def __init__(self, text_iter, text, length):
self.offset = text_iter.get_offset()
self.text = text
self.length = length
if self.length > 1 or self.text in ("\r", "\n", " "):
self.mergeable = False
else:
self.mergeable = True
class UndoableDelete(object):
"""something that has ben deleted from our textbuffer"""
def __init__(self, text_buffer, start_iter, end_iter):
self.text = text_buffer.get_text(start_iter, end_iter)
self.start = start_iter.get_offset()
self.end = end_iter.get_offset()
# need to find out if backspace or delete key has been used
# so we don't mess up during redo
insert_iter = text_buffer.get_iter_at_mark(text_buffer.get_insert())
if insert_iter.get_offset() <= self.start:
self.delete_key_used = True
else:
self.delete_key_used = False
if self.end - self.start > 1 or self.text in ("\r", "\n", " "):
self.mergeable = False
else:
self.mergeable = True
class UndoableBuffer(gtk.TextBuffer):
"""text buffer with added undo capabilities
designed as a drop-in replacement for gtksourceview,
at least as far as undo is concerned"""
def __init__(self):
"""
we'll need empty stacks for undo/redo and some state keeping
"""
gtk.TextBuffer.__init__(self)
self.undo_stack = []
self.redo_stack = []
self.not_undoable_action = False
self.undo_in_progress = False
self.connect('insert-text', self.on_insert_text)
self.connect('delete-range', self.on_delete_range)
@property
def can_undo(self):
return bool(self.undo_stack)
@property
def can_redo(self):
return bool(self.redo_stack)
def on_insert_text(self, textbuffer, text_iter, text, length):
def can_be_merged(prev, cur):
"""see if we can merge multiple inserts here
will try to merge words or whitespace
can't merge if prev and cur are not mergeable in the first place
can't merge when user set the input bar somewhere else
can't merge across word boundaries"""
WHITESPACE = (' ', '\t')
if not cur.mergeable or not prev.mergeable:
return False
elif cur.offset != (prev.offset + prev.length):
return False
elif cur.text in WHITESPACE and not prev.text in WHITESPACE:
return False
elif prev.text in WHITESPACE and not cur.text in WHITESPACE:
return False
return True
if not self.undo_in_progress:
self.redo_stack = []
if self.not_undoable_action:
return
undo_action = UndoableInsert(text_iter, text, length)
try:
prev_insert = self.undo_stack.pop()
except IndexError:
self.undo_stack.append(undo_action)
return
if not isinstance(prev_insert, UndoableInsert):
self.undo_stack.append(prev_insert)
self.undo_stack.append(undo_action)
return
if can_be_merged(prev_insert, undo_action):
prev_insert.length += undo_action.length
prev_insert.text += undo_action.text
self.undo_stack.append(prev_insert)
else:
self.undo_stack.append(prev_insert)
self.undo_stack.append(undo_action)
def on_delete_range(self, text_buffer, start_iter, end_iter):
def can_be_merged(prev, cur):
"""see if we can merge multiple deletions here
will try to merge words or whitespace
can't merge if prev and cur are not mergeable in the first place
can't merge if delete and backspace key were both used
can't merge across word boundaries"""
WHITESPACE = (' ', '\t')
if not cur.mergeable or not prev.mergeable:
return False
elif prev.delete_key_used != cur.delete_key_used:
return False
elif prev.start != cur.start and prev.start != cur.end:
return False
elif cur.text not in WHITESPACE and \
prev.text in WHITESPACE:
return False
elif cur.text in WHITESPACE and \
prev.text not in WHITESPACE:
return False
return True
if not self.undo_in_progress:
self.redo_stack = []
if self.not_undoable_action:
return
undo_action = UndoableDelete(text_buffer, start_iter, end_iter)
try:
prev_delete = self.undo_stack.pop()
except IndexError:
self.undo_stack.append(undo_action)
return
if not isinstance(prev_delete, UndoableDelete):
self.undo_stack.append(prev_delete)
self.undo_stack.append(undo_action)
return
if can_be_merged(prev_delete, undo_action):
if prev_delete.start == undo_action.start: # delete key used
prev_delete.text += undo_action.text
prev_delete.end += (undo_action.end - undo_action.start)
else: # Backspace used
prev_delete.text = "%s%s" % (undo_action.text,
prev_delete.text)
prev_delete.start = undo_action.start
self.undo_stack.append(prev_delete)
else:
self.undo_stack.append(prev_delete)
self.undo_stack.append(undo_action)
def begin_not_undoable_action(self):
"""don't record the next actions
toggles self.not_undoable_action"""
self.not_undoable_action = True
def end_not_undoable_action(self):
"""record next actions
toggles self.not_undoable_action"""
self.not_undoable_action = False
def undo(self):
"""undo inserts or deletions
undone actions are being moved to redo stack"""
if not self.undo_stack:
return
self.begin_not_undoable_action()
self.undo_in_progress = True
undo_action = self.undo_stack.pop()
self.redo_stack.append(undo_action)
if isinstance(undo_action, UndoableInsert):
start = self.get_iter_at_offset(undo_action.offset)
stop = self.get_iter_at_offset(
undo_action.offset + undo_action.length
)
self.delete(start, stop)
self.place_cursor(start)
else:
start = self.get_iter_at_offset(undo_action.start)
self.insert(start, undo_action.text)
stop = self.get_iter_at_offset(undo_action.end)
if undo_action.delete_key_used:
self.place_cursor(start)
else:
self.place_cursor(stop)
self.end_not_undoable_action()
self.undo_in_progress = False
def redo(self):
"""redo inserts or deletions
redone actions are moved to undo stack"""
if not self.redo_stack:
return
self.begin_not_undoable_action()
self.undo_in_progress = True
redo_action = self.redo_stack.pop()
self.undo_stack.append(redo_action)
if isinstance(redo_action, UndoableInsert):
start = self.get_iter_at_offset(redo_action.offset)
self.insert(start, redo_action.text)
new_cursor_pos = self.get_iter_at_offset(
redo_action.offset + redo_action.length
)
self.place_cursor(new_cursor_pos)
else:
start = self.get_iter_at_offset(redo_action.start)
stop = self.get_iter_at_offset(redo_action.end)
self.delete(start, stop)
self.place_cursor(start)
self.end_not_undoable_action()
self.undo_in_progress = False
def set_language(self, dummy_lang_obj):
pass
def set_highlight_syntax(self, dummy_bool):
pass
def set_highlight_matching_brackets(self, dummy_bool):
pass
#----------------------------------------------------------------------
View = gtk.TextView
Buffer = UndoableBuffer
#----------------------------------------------------------------------
class LanguageManager(object):
def get_search_path(self):
return []
def set_search_path(self, path_list):
pass
def get_language(self, lang_name):
return DummyLanguage()
#----------------------------------------------------------------------
class DummyLanguage(object):
pass