| import string |
| from Tkinter import * |
| from Delegator import Delegator |
| |
| #$ event <<redo>> |
| #$ win <Control-y> |
| #$ unix <Alt-z> |
| |
| #$ event <<undo>> |
| #$ win <Control-z> |
| #$ unix <Control-z> |
| |
| #$ event <<dump-undo-state>> |
| #$ win <Control-backslash> |
| #$ unix <Control-backslash> |
| |
| |
| class UndoDelegator(Delegator): |
| |
| max_undo = 1000 |
| |
| def __init__(self): |
| Delegator.__init__(self) |
| self.reset_undo() |
| |
| def setdelegate(self, delegate): |
| if self.delegate is not None: |
| self.unbind("<<undo>>") |
| self.unbind("<<redo>>") |
| self.unbind("<<dump-undo-state>>") |
| Delegator.setdelegate(self, delegate) |
| if delegate is not None: |
| self.bind("<<undo>>", self.undo_event) |
| self.bind("<<redo>>", self.redo_event) |
| self.bind("<<dump-undo-state>>", self.dump_event) |
| |
| def dump_event(self, event): |
| from pprint import pprint |
| pprint(self.undolist[:self.pointer]) |
| print "pointer:", self.pointer, |
| print "saved:", self.saved, |
| print "can_merge:", self.can_merge, |
| print "get_saved():", self.get_saved() |
| pprint(self.undolist[self.pointer:]) |
| return "break" |
| |
| def reset_undo(self): |
| self.was_saved = -1 |
| self.pointer = 0 |
| self.undolist = [] |
| self.undoblock = 0 # or a CommandSequence instance |
| self.set_saved(1) |
| |
| def set_saved(self, flag): |
| if flag: |
| self.saved = self.pointer |
| else: |
| self.saved = -1 |
| self.can_merge = False |
| self.check_saved() |
| |
| def get_saved(self): |
| return self.saved == self.pointer |
| |
| saved_change_hook = None |
| |
| def set_saved_change_hook(self, hook): |
| self.saved_change_hook = hook |
| |
| was_saved = -1 |
| |
| def check_saved(self): |
| is_saved = self.get_saved() |
| if is_saved != self.was_saved: |
| self.was_saved = is_saved |
| if self.saved_change_hook: |
| self.saved_change_hook() |
| |
| def insert(self, index, chars, tags=None): |
| self.addcmd(InsertCommand(index, chars, tags)) |
| |
| def delete(self, index1, index2=None): |
| self.addcmd(DeleteCommand(index1, index2)) |
| |
| # Clients should call undo_block_start() and undo_block_stop() |
| # around a sequence of editing cmds to be treated as a unit by |
| # undo & redo. Nested matching calls are OK, and the inner calls |
| # then act like nops. OK too if no editing cmds, or only one |
| # editing cmd, is issued in between: if no cmds, the whole |
| # sequence has no effect; and if only one cmd, that cmd is entered |
| # directly into the undo list, as if undo_block_xxx hadn't been |
| # called. The intent of all that is to make this scheme easy |
| # to use: all the client has to worry about is making sure each |
| # _start() call is matched by a _stop() call. |
| |
| def undo_block_start(self): |
| if self.undoblock == 0: |
| self.undoblock = CommandSequence() |
| self.undoblock.bump_depth() |
| |
| def undo_block_stop(self): |
| if self.undoblock.bump_depth(-1) == 0: |
| cmd = self.undoblock |
| self.undoblock = 0 |
| if len(cmd) > 0: |
| if len(cmd) == 1: |
| # no need to wrap a single cmd |
| cmd = cmd.getcmd(0) |
| # this blk of cmds, or single cmd, has already |
| # been done, so don't execute it again |
| self.addcmd(cmd, 0) |
| |
| def addcmd(self, cmd, execute=True): |
| if execute: |
| cmd.do(self.delegate) |
| if self.undoblock != 0: |
| self.undoblock.append(cmd) |
| return |
| if self.can_merge and self.pointer > 0: |
| lastcmd = self.undolist[self.pointer-1] |
| if lastcmd.merge(cmd): |
| return |
| self.undolist[self.pointer:] = [cmd] |
| if self.saved > self.pointer: |
| self.saved = -1 |
| self.pointer = self.pointer + 1 |
| if len(self.undolist) > self.max_undo: |
| ##print "truncating undo list" |
| del self.undolist[0] |
| self.pointer = self.pointer - 1 |
| if self.saved >= 0: |
| self.saved = self.saved - 1 |
| self.can_merge = True |
| self.check_saved() |
| |
| def undo_event(self, event): |
| if self.pointer == 0: |
| self.bell() |
| return "break" |
| cmd = self.undolist[self.pointer - 1] |
| cmd.undo(self.delegate) |
| self.pointer = self.pointer - 1 |
| self.can_merge = False |
| self.check_saved() |
| return "break" |
| |
| def redo_event(self, event): |
| if self.pointer >= len(self.undolist): |
| self.bell() |
| return "break" |
| cmd = self.undolist[self.pointer] |
| cmd.redo(self.delegate) |
| self.pointer = self.pointer + 1 |
| self.can_merge = False |
| self.check_saved() |
| return "break" |
| |
| |
| class Command: |
| |
| # Base class for Undoable commands |
| |
| tags = None |
| |
| def __init__(self, index1, index2, chars, tags=None): |
| self.marks_before = {} |
| self.marks_after = {} |
| self.index1 = index1 |
| self.index2 = index2 |
| self.chars = chars |
| if tags: |
| self.tags = tags |
| |
| def __repr__(self): |
| s = self.__class__.__name__ |
| t = (self.index1, self.index2, self.chars, self.tags) |
| if self.tags is None: |
| t = t[:-1] |
| return s + repr(t) |
| |
| def do(self, text): |
| pass |
| |
| def redo(self, text): |
| pass |
| |
| def undo(self, text): |
| pass |
| |
| def merge(self, cmd): |
| return 0 |
| |
| def save_marks(self, text): |
| marks = {} |
| for name in text.mark_names(): |
| if name != "insert" and name != "current": |
| marks[name] = text.index(name) |
| return marks |
| |
| def set_marks(self, text, marks): |
| for name, index in marks.items(): |
| text.mark_set(name, index) |
| |
| |
| class InsertCommand(Command): |
| |
| # Undoable insert command |
| |
| def __init__(self, index1, chars, tags=None): |
| Command.__init__(self, index1, None, chars, tags) |
| |
| def do(self, text): |
| self.marks_before = self.save_marks(text) |
| self.index1 = text.index(self.index1) |
| if text.compare(self.index1, ">", "end-1c"): |
| # Insert before the final newline |
| self.index1 = text.index("end-1c") |
| text.insert(self.index1, self.chars, self.tags) |
| self.index2 = text.index("%s+%dc" % (self.index1, len(self.chars))) |
| self.marks_after = self.save_marks(text) |
| ##sys.__stderr__.write("do: %s\n" % self) |
| |
| def redo(self, text): |
| text.mark_set('insert', self.index1) |
| text.insert(self.index1, self.chars, self.tags) |
| self.set_marks(text, self.marks_after) |
| text.see('insert') |
| ##sys.__stderr__.write("redo: %s\n" % self) |
| |
| def undo(self, text): |
| text.mark_set('insert', self.index1) |
| text.delete(self.index1, self.index2) |
| self.set_marks(text, self.marks_before) |
| text.see('insert') |
| ##sys.__stderr__.write("undo: %s\n" % self) |
| |
| def merge(self, cmd): |
| if self.__class__ is not cmd.__class__: |
| return False |
| if self.index2 != cmd.index1: |
| return False |
| if self.tags != cmd.tags: |
| return False |
| if len(cmd.chars) != 1: |
| return False |
| if self.chars and \ |
| self.classify(self.chars[-1]) != self.classify(cmd.chars): |
| return False |
| self.index2 = cmd.index2 |
| self.chars = self.chars + cmd.chars |
| return True |
| |
| alphanumeric = string.ascii_letters + string.digits + "_" |
| |
| def classify(self, c): |
| if c in self.alphanumeric: |
| return "alphanumeric" |
| if c == "\n": |
| return "newline" |
| return "punctuation" |
| |
| |
| class DeleteCommand(Command): |
| |
| # Undoable delete command |
| |
| def __init__(self, index1, index2=None): |
| Command.__init__(self, index1, index2, None, None) |
| |
| def do(self, text): |
| self.marks_before = self.save_marks(text) |
| self.index1 = text.index(self.index1) |
| if self.index2: |
| self.index2 = text.index(self.index2) |
| else: |
| self.index2 = text.index(self.index1 + " +1c") |
| if text.compare(self.index2, ">", "end-1c"): |
| # Don't delete the final newline |
| self.index2 = text.index("end-1c") |
| self.chars = text.get(self.index1, self.index2) |
| text.delete(self.index1, self.index2) |
| self.marks_after = self.save_marks(text) |
| ##sys.__stderr__.write("do: %s\n" % self) |
| |
| def redo(self, text): |
| text.mark_set('insert', self.index1) |
| text.delete(self.index1, self.index2) |
| self.set_marks(text, self.marks_after) |
| text.see('insert') |
| ##sys.__stderr__.write("redo: %s\n" % self) |
| |
| def undo(self, text): |
| text.mark_set('insert', self.index1) |
| text.insert(self.index1, self.chars) |
| self.set_marks(text, self.marks_before) |
| text.see('insert') |
| ##sys.__stderr__.write("undo: %s\n" % self) |
| |
| class CommandSequence(Command): |
| |
| # Wrapper for a sequence of undoable cmds to be undone/redone |
| # as a unit |
| |
| def __init__(self): |
| self.cmds = [] |
| self.depth = 0 |
| |
| def __repr__(self): |
| s = self.__class__.__name__ |
| strs = [] |
| for cmd in self.cmds: |
| strs.append(" %r" % (cmd,)) |
| return s + "(\n" + ",\n".join(strs) + "\n)" |
| |
| def __len__(self): |
| return len(self.cmds) |
| |
| def append(self, cmd): |
| self.cmds.append(cmd) |
| |
| def getcmd(self, i): |
| return self.cmds[i] |
| |
| def redo(self, text): |
| for cmd in self.cmds: |
| cmd.redo(text) |
| |
| def undo(self, text): |
| cmds = self.cmds[:] |
| cmds.reverse() |
| for cmd in cmds: |
| cmd.undo(text) |
| |
| def bump_depth(self, incr=1): |
| self.depth = self.depth + incr |
| return self.depth |
| |
| def main(): |
| from Percolator import Percolator |
| root = Tk() |
| root.wm_protocol("WM_DELETE_WINDOW", root.quit) |
| text = Text() |
| text.pack() |
| text.focus_set() |
| p = Percolator(text) |
| d = UndoDelegator() |
| p.insertfilter(d) |
| root.mainloop() |
| |
| if __name__ == "__main__": |
| main() |