###############################################################################
# Name: ed_basestc.py                                                         #
# Purpose: Editra's base StyledTextCtrl.                                      #
# Author: Cody Precord <cprecord@editra.org>                                  #
# Copyright: (c) 2009 Cody Precord <staff@editra.org>                         #
# License: wxWindows License                                                  #
###############################################################################

"""
The EditraBaseStc is the base StyledTextCtrl that provides automatic styling and
syntax highlighting of all supported filetypes.

@summary: Editra's base styled text ctrl.

"""

__author__ = "Cody Precord <cprecord@editra.org>"
__svnid__ = "$Id: ed_basestc.py 60504 2009-05-03 18:31:47Z CJP $"
__revision__ = "$Revision: 60504 $"

#-----------------------------------------------------------------------------#
# Imports
import wx
import wx.stc

# Editra Imports
import ed_glob
import ed_style
import eclib
import ed_msg
import ed_txt
from syntax import syntax
from autocomp import autocomp
from extern import vertedit
from profiler import Profile_Get

#-----------------------------------------------------------------------------#

# Margins
MARK_MARGIN = 0
NUM_MARGIN  = 1
FOLD_MARGIN = 2

# Key code additions
ALT_SHIFT = wx.stc.STC_SCMOD_ALT|wx.stc.STC_SCMOD_SHIFT
CTRL_SHIFT = wx.stc.STC_SCMOD_CTRL|wx.stc.STC_SCMOD_SHIFT

#-----------------------------------------------------------------------------#

class EditraBaseStc(wx.stc.StyledTextCtrl, ed_style.StyleMgr):
    """Base StyledTextCtrl that provides all the base code editing
    functionatlity.

    """
    ED_STC_MASK_MARKERS = ~wx.stc.STC_MASK_FOLDERS
    def __init__(self, parent, id_,
                 pos=wx.DefaultPosition, size=wx.DefaultSize, style=0):
        wx.stc.StyledTextCtrl.__init__(self, parent, id_, pos, size, style)
        ed_style.StyleMgr.__init__(self, self.GetStyleSheet())

        # Attributes
        self.file = ed_txt.EdFile()
        self._code = dict(compsvc=autocomp.AutoCompService.GetCompleter(self),
                          synmgr=syntax.SyntaxMgr(ed_glob.CONFIG['CACHE_DIR']),
                          keywords=[ ' ' ],
                          comment=list(),
                          clexer=None,      # Container lexer method
                          indenter=None,    # Auto indenter
                          lang_id=0)        # Language ID from syntax module

        self.vert_edit = vertedit.VertEdit(self)

        # Set Up Margins
        ## Outer Left Margin Bookmarks
        self.SetMarginType(MARK_MARGIN, wx.stc.STC_MARGIN_SYMBOL)
        self.SetMarginMask(MARK_MARGIN, self.ED_STC_MASK_MARKERS)
        self.SetMarginSensitive(MARK_MARGIN, True)
        self.SetMarginWidth(MARK_MARGIN, 12)

        ## Middle Left Margin Line Number Indication
        self.SetMarginType(NUM_MARGIN, wx.stc.STC_MARGIN_NUMBER)
        self.SetMarginMask(NUM_MARGIN, 0)

        ## Inner Left Margin Setup Folders
        self.SetMarginType(FOLD_MARGIN, wx.stc.STC_MARGIN_SYMBOL)
        self.SetMarginMask(FOLD_MARGIN, wx.stc.STC_MASK_FOLDERS)
        self.SetMarginSensitive(FOLD_MARGIN, True)

        # Set Mac specific keybindings
        if wx.Platform == '__WXMAC__':
            for keys in _GetMacKeyBindings():
                self.CmdKeyAssign(*keys)

        # Setup Autocomp images
        # TODO: should be called on theme change messages
        self.RegisterImages()

        # Event Handlers
        self.Bind(wx.stc.EVT_STC_CHANGE, self.OnChanged)
        self.Bind(wx.stc.EVT_STC_MODIFIED, self.OnModified)

    def __del__(self):
        # Cleanup the file object callbacks
        self.file.RemoveModifiedCallback(self.FireModified)
        self.file.CleanUp()

    #---- Public Methods ----#

    def AutoIndent(self):
        """Indent from the current postion to match the indentation
        of the previous line.
        @postcondition: proper type of white space is added from current pos
                        to match that of indentation in above line
        """
        cpos = self.GetCurrentPos()

        # Check if a special purpose indenter has been registered
        if self._code['indenter'] is not None:
            txt = self._code['indenter'](self, cpos, self.GetIndentChar())
            txt = txt.replace('\n', self.GetEOLChar())
        else:
            # Default Indenter
            line = self.GetCurrentLine()
            text = self.GetTextRange(self.PositionFromLine(line), cpos)
            if text.strip() == u'':
                self.AddText(self.GetEOLChar() + text)
                self.EnsureCaretVisible()
                return
            indent = self.GetLineIndentation(line)
            i_space = indent / self.GetTabWidth()
            ndent = self.GetEOLChar() + self.GetIndentChar() * i_space
            txt = ndent + ((indent - (self.GetTabWidth() * i_space)) * u' ')

        self.AddText(txt)
        self.EnsureCaretVisible()

    def BraceBadLight(self, pos):
        """Highlight the character at the given position
        @param pos: position of character to highlight with STC_STYLE_BRACEBAD

        """
        # Check if we are still alive or not, as this may be called
        # after we have been deleted.
        if isinstance(self, wx.stc.StyledTextCtrl):
            super(EditraBaseStc, self).BraceBadLight(pos)

    def BraceHighlight(self, pos1, pos2):
        """Highlight characters at pos1 and pos2
        @param pos1: position of char 1
        @param pos2: position of char 2

        """
        # Check if we are still alive or not, as this may be called
        # after we have been deleted.
        if isinstance(self, wx.stc.StyledTextCtrl):
            super(EditraBaseStc, self).BraceHighlight(pos1, pos2)

    def CanCopy(self):
        """Check if copy/cut is possible"""
        return self.GetSelectionStart() != self.GetSelectionEnd()

    CanCut = CanCopy

    def Comment(self, start, end, uncomment=False):
        """(Un)Comments a line or a selected block of text
        in a document.
        @param start: begining line (int)
        @param end: end line (int)
        @keyword uncomment: uncomment selection

        """
        if len(self._code['comment']):
            sel = self.GetSelection()
            c_start = self._code['comment'][0]
            c_end = u''
            if len(self._code['comment']) > 1:
                c_end = self._code['comment'][1]

            # Modify the selected line(s)
            self.BeginUndoAction()
            try:
                nchars = 0
                lines = range(start, end+1)
                lines.reverse()
                for line_num in lines:
                    lstart = self.PositionFromLine(line_num)
                    lend = self.GetLineEndPosition(line_num)
                    text = self.GetTextRange(lstart, lend)
                    tmp = text.strip()
                    if len(tmp):
                        if uncomment:
                            if tmp.startswith(c_start):
                                text = text.replace(c_start, u'', 1)
                            if c_end and tmp.endswith(c_end):
                                text = text.replace(c_end, u'', 1)
                            nchars = nchars - len(c_start + c_end)
                        else:
                            text = c_start + text + c_end
                            nchars = nchars + len(c_start + c_end)

                        self.SetTargetStart(lstart)
                        self.SetTargetEnd(lend)
                        self.ReplaceTarget(text)
            finally:
                self.EndUndoAction()
                if sel[0] != sel[1]:
                    self.SetSelection(sel[0], sel[1] + nchars)
                else:
                    if len(self._code['comment']) > 1:
                        nchars = nchars - len(self._code['comment'][1])
                    self.GotoPos(sel[0] + nchars)

    def ConfigureAutoComp(self):
        """Sets up the Autocompleter, the autocompleter
        configuration depends on the currently set lexer
        @postcondition: autocomp is configured

        """
        self.AutoCompSetAutoHide(False)
        self.AutoCompSetChooseSingle(True)
        extend = Profile_Get('AUTO_COMP_EX') # Using extended autocomp?
        self._code['compsvc'] = autocomp.AutoCompService.GetCompleter(self, extend)
        self.AutoCompSetIgnoreCase(not self._code['compsvc'].GetCaseSensitive())
        self.AutoCompStops(self._code['compsvc'].GetAutoCompStops())
        # TODO: come back to this it can cause some annoying behavior where
        #       it automatically completes strings that you don't want to be
        #       inserted in the buffer. (i.e typing self._value will bring up
        #       the autocomp list but if self._value is not in the list and you
        #       hit space it will automatically insert something from the list.)
#        self.AutoCompSetFillUps(self._code['compsvc'].GetAutoCompFillups())

    def ConfigureLexer(self, file_ext):
        """Sets Lexer and Lexer Keywords for the specifed file extension
        @param file_ext: a file extension to configure the lexer from

        """
        syn_data = self._code['synmgr'].SyntaxData(file_ext)

        # Set the ID of the selected lexer
        try:
            self._code['lang_id'] = syn_data[syntax.LANGUAGE]
        except KeyError:
            self._code['lang_id'] = 0

        lexer = syn_data[syntax.LEXER]
        # Check for special cases
        # TODO: add fetch method to check if container lexer requires extra
        #       style bytes beyond the default 5.
        if lexer in [ wx.stc.STC_LEX_HTML, wx.stc.STC_LEX_XML]:
            self.SetStyleBits(7)
        elif lexer == wx.stc.STC_LEX_NULL:
            self.SetStyleBits(5)
            self.SetLexer(lexer)
            self.ClearDocumentStyle()
            self.UpdateBaseStyles()
            return True
        else:
            self.SetStyleBits(5)

        try:
            keywords = syn_data[syntax.KEYWORDS]
        except KeyError:
            keywords = []

        try:
            synspec = syn_data[syntax.SYNSPEC]
        except KeyError:
            synspec = []

        try:
            props = syn_data[syntax.PROPERTIES]
        except KeyError:
            props = []

        try:
            comment = syn_data[syntax.COMMENT]
        except KeyError:
            comment = []

        try:
            clexer = syn_data[syntax.CLEXER]
        except KeyError:
            clexer = None

        try:
            indenter = syn_data[syntax.INDENTER]
        except KeyError:
            indenter = None

        # Set Lexer
        self.SetLexer(lexer)
        # Set Keywords
        self.SetKeyWords(keywords)
        # Set Lexer/Syntax Specifications
        self.SetSyntax(synspec)
        # Set Extra Properties
        self.SetProperties(props)
        # Set Comment Pattern
        self._code['comment'] = comment
        # Set the Container Lexer Method
        self._code['clexer'] = clexer
        # Auto-indenter function
        self._code['indenter'] = indenter

    def DefineMarkers(self):
        """Defines the folder and bookmark icons for this control
        @postcondition: all margin markers are defined

        """
        style = self.GetItemByName('foldmargin_style')
        # The foreground/background settings for the marker column seem to
        # backwards from what the parameters take so use our Fore color for
        # the stcs back and visa versa for our Back color.
        back = style.GetFore()
        rgb = eclib.HexToRGB(back[1:])
        back = wx.Colour(red=rgb[0], green=rgb[1], blue=rgb[2])

        fore = style.GetBack()
        rgb = eclib.HexToRGB(fore[1:])
        fore = wx.Colour(red=rgb[0], green=rgb[1], blue=rgb[2])

        self.MarkerDefine(wx.stc.STC_MARKNUM_FOLDEROPEN,
                          wx.stc.STC_MARK_BOXMINUS, fore, back)
        self.MarkerDefine(wx.stc.STC_MARKNUM_FOLDER,
                          wx.stc.STC_MARK_BOXPLUS,  fore, back)
        self.MarkerDefine(wx.stc.STC_MARKNUM_FOLDERSUB,
                          wx.stc.STC_MARK_VLINE, fore, back)
        self.MarkerDefine(wx.stc.STC_MARKNUM_FOLDERTAIL,
                          wx.stc.STC_MARK_LCORNER, fore, back)
        self.MarkerDefine(wx.stc.STC_MARKNUM_FOLDEREND,
                          wx.stc.STC_MARK_BOXPLUSCONNECTED, fore, back)
        self.MarkerDefine(wx.stc.STC_MARKNUM_FOLDEROPENMID,
                          wx.stc.STC_MARK_BOXMINUSCONNECTED, fore, back)
        self.MarkerDefine(wx.stc.STC_MARKNUM_FOLDERMIDTAIL,
                          wx.stc.STC_MARK_TCORNER, fore, back)
        self.MarkerDefine(0, wx.stc.STC_MARK_SHORTARROW, fore, back)
        self.SetFoldMarginHiColour(True, fore)
        self.SetFoldMarginColour(True, fore)

    def DoZoom(self, mode):
        """Zoom control in or out
        @param mode: either zoom in or out
        @type mode: int id value

        """
        id_type = mode
        zoomlevel = self.GetZoom()
        if id_type == ed_glob.ID_ZOOM_OUT:
            if zoomlevel > -9:
                self.ZoomOut()
        elif id_type == ed_glob.ID_ZOOM_IN:
            if zoomlevel < 19:
                self.ZoomIn()
        else:
            self.SetZoom(0)
        return self.GetZoom()

    @property
    def File(self):
        return self.file

    def FindLexer(self, set_ext=u''):
        """Sets Text Controls Lexer Based on File Extension
        @param set_ext: explicit extension to use in search
        @postcondition: lexer is configured for file

        """
        if set_ext != u'':
            ext = set_ext.lower()
        else:
            ext = self.file.GetExtension()
        self.ClearDocumentStyle()

        # Configure Lexer from File Extension
        self.ConfigureLexer(ext)

        # If syntax auto detection fails from file extension try to
        # see if there is an interpreter line that can be parsed.
        if self.GetLexer() == wx.stc.STC_LEX_NULL:
            interp = self.GetLine(0)
            if interp != wx.EmptyString:
                interp = interp.split(u"/")[-1]
                interp = interp.strip().split()
                if len(interp) and interp[-1][0] != "-":
                    interp = interp[-1]
                elif len(interp):
                    interp = interp[0]
                else:
                    interp = u''
                ex_map = { "python" : "py", "wish" : "tcl", "ruby" : "rb",
                           "bash" : "sh", "csh" : "csh", "perl" : "pl",
                           "ksh" : "ksh", "php" : "php", "booi" : "boo",
                           "pike" : "pike"}
                self.ConfigureLexer(ex_map.get(interp, interp))
        self.Colourise(0, -1)

    def FireModified(self):
        """Fire a modifed event"""
        self.OnChanged(wx.stc.StyledTextEvent(wx.stc.wxEVT_STC_CHANGE,
                                              self.GetId()))

    def GetCommandStr(self):
        """Gets the command string to the left of the autocomp
        activation character.
        @return: the command string to the left of the autocomp char
        @todo: fillups are currently disabled. See note in Configure.

        """
        # NOTE: the column position retuned by GetCurLine is not correct
        #       for multibyte characters.
        line, col = self.GetCurLine()
        col = self.GetColumn(self.GetCurrentPos())
        cmd_lmt = list(self._code['compsvc'].GetAutoCompStops() + \
                       self._code['compsvc'].GetAutoCompFillups())
        for key in self._code['compsvc'].GetAutoCompKeys():
            kval = unichr(key)
            if kval in cmd_lmt:
                cmd_lmt.remove(kval)

        curr_pos = col - 1
        cmd = u''
        while curr_pos > -1:
            cmd = line[curr_pos:col]
            if len(cmd) and cmd[0] not in cmd_lmt:
                curr_pos -= 1
            else:
                break

        for char in cmd_lmt:
            cmd = cmd.replace(char, u'')

        return cmd.strip()

    def GetCommentChars(self):
        """Return the list of characters used to comment a string in the
        current language.
        @return: list of strings

        """
        return self._code['comment']

    def GetCompleter(self):
        """Get this buffers completer object
        @return: Completer

        """
        return self._code['compsvc']

    def GetDocument(self):
        """Return a reference to the document object represented in this buffer.
        @return: EdFile
        @see: L{ed_txt.EdFile}

        """
        return self.file

    def GetEOLChar(self):
        """Gets the eol character used in document
        @return: the character used for eol in this document

        """
        m_id = self.GetEOLMode()
        if m_id == wx.stc.STC_EOL_CR:
            return u'\r'
        elif m_id == wx.stc.STC_EOL_CRLF:
            return u'\r\n'
        else:
            return u'\n'

    def GetFileName(self):
        """Returns the full path name of the current file
        @return: full path name of document

        """
        return self.file.GetPath()

    def GetIndentChar(self):
        """Gets the indentation char used in document
        @return: indentation char used either space or tab

        """
        if self.GetUseTabs():
            return u'\t'
        else:
            return u' ' * self.GetIndent()

    def GetKeywords(self):
        """Get the keyword set for the current document.
        @return: list of strings

        """
        return self._code['keywords']

    def GetLangId(self):
        """Returns the language identifer of this control
        @return: language identifier of document
        @rtype: int

        """
        return self._code['lang_id']

    def GetModTime(self):
        """Get the value of the buffers file last modtime"""
        return self.file.GetModtime()

    def GetPos(self):
        """Update Line/Column information
        @return: tuple (line, column)

        """
        return (self.GetCurrentLine() + 1, self.GetColumn(self.GetCurrentPos()))

    def IsColumnMode(self):
        """Is the buffer in column edit mode
        @return: bool

        """
        return self.VertEdit.Enabled

    def IsComment(self, pos):
        """Is the given position in a comment region of the current buffer
        @param pos: int position in buffer
        @return: bool

        """
        pos = max(0, pos-1)
        return 'comment' in self.FindTagById(self.GetStyleAt(pos))

    def InitCompleter(self):
        """(Re)Initialize a completer object for this buffer"""
        self._code['compsvc'] = autocomp.AutoCompService.GetCompleter(self)

    def IsString(self, pos):
        """Is the given position in a string region of the current buffer
        @param pos: int position in buffer
        @return: bool

        """
        style = self.GetStyleAt(pos)
        return self.FindTagById(style) in ('string_style', 'char_style')

    def LoadFile(self, path):
        """Load the file at the given path into the buffer. Returns
        True if no errors and False otherwise. To retrieve the errors
        check the last error that was set in the file object returned by
        L{GetDocument}.
        @param path: path to file

        """
        # Post notification that a file load is starting
        ed_msg.PostMessage(ed_msg.EDMSG_FILE_OPENING, path)
        self.file.SetPath(path)
        txt = self.file.Read()
        if txt is not None:
            self.SetText(txt)
        else:
            self.file.SetPath('')
            return False

        if self.file.GetLastError() != 'None':
            # Return false if there was an encoding error and a fallback
            # was used. So the caller knows to check the error status
            return False
        else:
            return True

    def OnChanged(self, evt):
        """Handles updates that need to take place after
        the control has been modified.
        @param evt: event that called this handler
        @type evt: wx.stc.StyledTextEvent

        """
        # Adjust line number margin width to expand as needed when line
        # number width over fills the area.
        lines = self.GetLineCount()
        mwidth = self.GetTextExtent(str(lines))[0]

        if wx.Platform == '__WXMAC__':
            adj = 2
        else:
            adj = 8

        nwidth = max(15, mwidth + adj)
        if self.GetMarginWidth(NUM_MARGIN) != nwidth:
            self.SetMarginWidth(NUM_MARGIN, nwidth)

        wx.PostEvent(self.GetParent(), evt)
        ed_msg.PostMessage(ed_msg.EDMSG_UI_STC_CHANGED)

    def OnModified(self, evt):
        """Handle modify events, includes style changes!"""
        if self.VertEdit.Enabled:
            self.VertEdit.OnModified(evt)
        else:
            evt.Skip()

    def OnStyleNeeded(self, evt):
        """Perform custom styling when registered for a container lexer"""
        if self._code['clexer'] is not None:
            self._code['clexer'](self, self.GetEndStyled(), evt.GetPosition())
        else:
            evt.Skip()

    def RegisterImages(self):
        """Register the images for the autocomp popup list"""
        images = [(autocomp.IMG_FUNCTION, ed_glob.ID_FUNCT_TYPE),
                  (autocomp.IMG_METHOD, ed_glob.ID_METHOD_TYPE),
                  (autocomp.IMG_PROPERTY, ed_glob.ID_PROPERTY_TYPE),
                  (autocomp.IMG_ATTRIBUTE, ed_glob.ID_ATTR_TYPE),
                  (autocomp.IMG_CLASS, ed_glob.ID_CLASS_TYPE),
                  (autocomp.IMG_VARIABLE, ed_glob.ID_VARIABLE_TYPE),
                  (autocomp.IMG_ELEMENT, ed_glob.ID_ELEM_TYPE)]
        for idx, img in images:
            bmp = wx.ArtProvider.GetBitmap(str(img), wx.ART_MENU)
            if bmp.IsOk():
                self.RegisterImage(idx, bmp)

    def SetDocument(self, doc):
        """Change the document object used.
        @param doc: an L{ed_txt.EdFile} instance

        """
        del self.file
        self.file = doc

    def SetEncoding(self, enc):
        """Sets the encoding of the current document
        @param enc: encoding to set for document

        """
        self.file.SetEncoding(enc)

    def SetFileName(self, path):
        """Set the buffers filename attributes from the given path"""
        self.file.SetPath(path)

    def SetFocus(self):
        """Set the focus to this control
        @note: overridden as a hack for msw

        """
        super(EditraBaseStc, self).SetFocus()
        if wx.Platform == '__WXMSW__':
            wx.PostEvent(self, wx.FocusEvent(wx.wxEVT_SET_FOCUS, self.GetId()))

    def SetKeyWords(self, kw_lst):
        """Sets the keywords from a list of keyword sets
        @param kw_lst: [ (KWLVL, "KEWORDS"), (KWLVL2, "KEYWORDS2"), ect...]
        @todo: look into if the uniquifying of the list has a more optimal
               solution.

        """
        # Parse Keyword Settings List simply ignoring bad values and badly
        # formed lists
        self._code['keywords'] = list()
        kwlist = ""
        for keyw in kw_lst:
            if len(keyw) != 2:
                continue
            else:
                if not isinstance(keyw[0], int) or \
                   not isinstance(keyw[1], basestring):
                    continue
                else:
                    kwlist += keyw[1]
                    super(EditraBaseStc, self).SetKeyWords(keyw[0], keyw[1])

        kwlist = kwlist.split()         # Split into a list of words
        kwlist = list(set(kwlist))      # Uniqueify the list
        kwlist.sort()                   # Sort into alphbetical order

        # Can't have ? in scintilla autocomp list unless specifying an image
        if '?' in kwlist:
            kwlist.remove('?')
        self._code['keywords'] = kwlist

    def SetLexer(self, lexer):
        """Set the buffers lexer
        @param lexer: lexer to use
        @note: Overrides StyledTextCtrl.SetLexer

        """
        if lexer == wx.stc.STC_LEX_CONTAINER:
            # If setting a container lexer only bind the event if it hasn't
            # been done yet.
            if self._code['clexer'] is None:
                self.Bind(wx.stc.EVT_STC_STYLENEEDED, self.OnStyleNeeded)
        else:
            # If changing from a container lexer to a non container
            # lexer we need to unbind the event.
            if self._code['clexer'] is not None:
                self.Unbind(wx.stc.EVT_STC_STYLENEEDED)
                self._code['clexer'] = None

        super(EditraBaseStc, self).SetLexer(lexer)

    def SetModTime(self, modtime):
        """Set the value of the files last modtime"""
        self.file.SetModTime(modtime)

    def SetProperties(self, prop_lst):
        """Sets the Lexer Properties from a list of specifications
        @param prop_lst: [ ("PROPERTY", "VAL"), ("PROPERTY2", "VAL2) ]

        """
        # Parses Property list, ignoring all bad values
        for prop in prop_lst:
            if len(prop) != 2:
                continue
            else:
                if not isinstance(prop[0], basestring) or not \
                   isinstance(prop[1], basestring):
                    continue
                else:
                    self.SetProperty(prop[0], prop[1])
        return True

    def ShowAutoCompOpt(self, command):
        """Shows the autocompletion options list for the command
        @param command: command to look for autocomp options for

        """
        pos = self.GetCurrentPos()
        lst = self._code['compsvc'].GetAutoCompList(command)
        if lst is not None and len(lst):
            self.BeginUndoAction()
            lst = u' '.join(lst)
            if lst.isspace():
                return

            self.AutoCompShow(pos - self.WordStartPosition(pos, True), lst)

            if len(lst) == 1 and self._code['compsvc'].GetAutoCompAfter():
                super(EditraBaseStc, self).GotoPos(pos)
            self.EndUndoAction()
            self.SetFocus()

    def ShowCallTip(self, command):
        """Shows call tip for given command
        @param command: command to  look for calltips for

        """
        if self.CallTipActive():
            self.CallTipCancel()

        tip = self._code['compsvc'].GetCallTip(command)
        if len(tip):
            curr_pos = self.GetCurrentPos()
            tip_pos = curr_pos - (len(command.split('.')[-1]) + 1)
            fail_safe = curr_pos - self.GetColumn(curr_pos)
            self.CallTipShow(max(tip_pos, fail_safe), tip)

    def ToggleColumnMode(self):
        """Toggle the column edit mode"""
        self.VertEdit.enable(not self.VertEdit.Enabled)

    def ToggleComment(self):
        """Toggle the comment of the selected region"""
        if len(self._code['comment']):
            sel = self.GetSelection()
            start = self.LineFromPosition(sel[0])
            end = self.LineFromPosition(sel[1])
            c_start = self._code['comment'][0]

            if end > start and self.GetColumn(sel[1]) == 0:
                end = end - 1

            # Analyze the seleted line(s)
            comment = 0
            for line in range(start, end+1):
                txt = self.GetLine(line)
                if txt.lstrip().startswith(c_start):
                    comment += 1

            lcount = end - start
            mod = 1
            if lcount == 0:
                mod = 0

            if comment > (lcount / 2) + mod:
                # Uncomment
                self.Comment(start, end, True)
            else:
                self.Comment(start, end, False)

    def ToggleLineNumbers(self, switch=None):
        """Toggles the visibility of the line number margin
        @keyword switch: force a particular setting

        """
        if (switch is None and \
            not self.GetMarginWidth(NUM_MARGIN)) or switch:
            self.SetMarginWidth(NUM_MARGIN, 30)
        else:
            self.SetMarginWidth(NUM_MARGIN, 0)

    @property
    def VertEdit(self):
        """Vertical edit mode accessor."""
        return self.vert_edit

    #---- Style Function Definitions ----#
    def RefreshStyles(self):
        """Refreshes the colorization of the window by reloading any
        style tags that may have been modified.
        @postcondition: all style settings are refreshed in the control

        """
        self.Freeze()
        self.StyleClearAll()
        self.SetSyntax(self.GetSyntaxParams())
        self.DefineMarkers()
        self.Thaw()
        self.Refresh()

    def UpdateBaseStyles(self):
        """Update the controls basic styles"""
        super(EditraBaseStc, self).UpdateBaseStyles()

        # Set control specific styles
        sback = self.GetItemByName('select_style')
        if not sback.IsNull():
            sback = sback.GetBack()
        else:
            sback = wx.SystemSettings.GetColour(wx.SYS_COLOUR_HIGHLIGHT)
        self.vert_edit.SetBlockColor(sback)
        self.DefineMarkers()

#-----------------------------------------------------------------------------#

def _GetMacKeyBindings():
    """Returns a list of 3-element tuples defining the standard key
    bindings for Mac text editors -- i.e., the behavior of option-arrow,
    shift-delete, and so on.

    @return: list of (key code, modifier keys, STC action)

    """
    # A good reference for these: http://www.yellowbrain.com/stc/keymap.html
    return [
            # Move/select/delete by word
            (wx.stc.STC_KEY_LEFT, wx.stc.STC_SCMOD_ALT,
             wx.stc.STC_CMD_WORDLEFT),
            (wx.stc.STC_KEY_RIGHT, wx.stc.STC_SCMOD_ALT,
             wx.stc.STC_CMD_WORDRIGHT),
            (wx.stc.STC_KEY_LEFT, ALT_SHIFT, wx.stc.STC_CMD_WORDLEFTEXTEND),
            (wx.stc.STC_KEY_RIGHT, ALT_SHIFT, wx.stc.STC_CMD_WORDRIGHTEXTEND),
            (wx.stc.STC_KEY_BACK, wx.stc.STC_SCMOD_ALT,
             wx.stc.STC_CMD_DELWORDLEFT),
            (wx.stc.STC_KEY_DELETE, wx.stc.STC_SCMOD_ALT,
             wx.stc.STC_CMD_DELWORDRIGHT),
            (wx.stc.STC_KEY_BACK, ALT_SHIFT, wx.stc.STC_CMD_DELWORDRIGHT),
            (wx.stc.STC_KEY_DELETE, ALT_SHIFT, wx.stc.STC_CMD_DELWORDLEFT),

            # Move/select/delete by line
            (wx.stc.STC_KEY_LEFT, wx.stc.STC_SCMOD_CTRL,
             wx.stc.STC_CMD_VCHOME),
            (wx.stc.STC_KEY_LEFT, CTRL_SHIFT, wx.stc.STC_CMD_VCHOMEEXTEND),
            (wx.stc.STC_KEY_RIGHT, wx.stc.STC_SCMOD_CTRL,
             wx.stc.STC_CMD_LINEEND),
            (wx.stc.STC_KEY_RIGHT, CTRL_SHIFT, wx.stc.STC_CMD_LINEENDEXTEND),
            (wx.stc.STC_KEY_BACK, wx.stc.STC_SCMOD_CTRL,
             wx.stc.STC_CMD_DELLINELEFT),
            (wx.stc.STC_KEY_DELETE, wx.stc.STC_SCMOD_CTRL,
             wx.stc.STC_CMD_DELLINERIGHT),
            (wx.stc.STC_KEY_BACK, CTRL_SHIFT, wx.stc.STC_CMD_DELLINERIGHT),
            (wx.stc.STC_KEY_DELETE, CTRL_SHIFT, wx.stc.STC_CMD_DELLINELEFT),

            # By-character deletion behavior
            (wx.stc.STC_KEY_BACK, wx.stc.STC_SCMOD_NORM,
             wx.stc.STC_CMD_DELETEBACK),
            (wx.stc.STC_KEY_DELETE, wx.stc.STC_SCMOD_SHIFT,
             wx.stc.STC_CMD_DELETEBACK),

            # NOTE: The following two are a special case, since Scintilla
            # doesn't have a forward-delete action.  So here we just cancel any
            # tip our auto-completion display, and then implement forward
            # delete in OnKeyDown.
            #(wx.stc.STC_KEY_DELETE, 0, wx.stc.STC_CMD_CANCEL),
            (wx.stc.STC_KEY_BACK, wx.stc.STC_SCMOD_SHIFT,
             wx.stc.STC_CMD_CANCEL),
            ]
