import os
import types

import wx
import wx.lib.buttons

from EditorPanel import EditorPanel

from IDEFrame import TITLE, FILEMENU, PROJECTTREE, PAGETITLES

from controls import TextCtrlAutoComplete
from dialogs import BrowseValuesLibraryDialog
from util.BitmapLibrary import GetBitmap

if wx.Platform == '__WXMSW__':
    faces = { 'times': 'Times New Roman',
              'mono' : 'Courier New',
              'helv' : 'Arial',
              'other': 'Comic Sans MS',
              'size' : 16,
             }
else:
    faces = { 'times': 'Times',
              'mono' : 'Courier',
              'helv' : 'Helvetica',
              'other': 'new century schoolbook',
              'size' : 18,
             }

SCROLLBAR_UNIT = 10
WINDOW_COLOUR = wx.Colour(240, 240, 240)

CWD = os.path.split(os.path.realpath(__file__))[0]

def Bpath(*args):
    return os.path.join(CWD,*args)

# Some helpers to tweak GenBitmapTextButtons
# TODO: declare customized classes instead.
gen_mini_GetBackgroundBrush = lambda obj:lambda dc: wx.Brush(obj.GetParent().GetBackgroundColour(), wx.SOLID)
gen_textbutton_GetLabelSize = lambda obj:lambda:(wx.lib.buttons.GenButton._GetLabelSize(obj)[:-1] + (False,))

def make_genbitmaptogglebutton_flat(button):
    button.GetBackgroundBrush = gen_mini_GetBackgroundBrush(button)
    button.labelDelta = 0
    button.SetBezelWidth(0)
    button.SetUseFocusIndicator(False)

# Patch wx.lib.imageutils so that gray is supported on alpha images
import wx.lib.imageutils
from wx.lib.imageutils import grayOut as old_grayOut
def grayOut(anImage):
    if anImage.HasAlpha():
        AlphaData = anImage.GetAlphaData()
    else :
        AlphaData = None

    old_grayOut(anImage)

    if AlphaData is not None:
        anImage.SetAlphaData(AlphaData)

wx.lib.imageutils.grayOut = grayOut

class GenBitmapTextButton(wx.lib.buttons.GenBitmapTextButton):
    def _GetLabelSize(self):
        """ used internally """
        w, h = self.GetTextExtent(self.GetLabel())
        if not self.bmpLabel:
            return w, h, False       # if there isn't a bitmap use the size of the text

        w_bmp = self.bmpLabel.GetWidth()+2
        h_bmp = self.bmpLabel.GetHeight()+2
        height = h + h_bmp
        if w_bmp > w:
            width = w_bmp
        else:
            width = w
        return width, height, False

    def DrawLabel(self, dc, width, height, dw=0, dy=0):
        bmp = self.bmpLabel
        if bmp != None:     # if the bitmap is used
            if self.bmpDisabled and not self.IsEnabled():
                bmp = self.bmpDisabled
            if self.bmpFocus and self.hasFocus:
                bmp = self.bmpFocus
            if self.bmpSelected and not self.up:
                bmp = self.bmpSelected
            bw,bh = bmp.GetWidth(), bmp.GetHeight()
            if not self.up:
                dw = dy = self.labelDelta
            hasMask = bmp.GetMask() != None
        else:
            bw = bh = 0     # no bitmap -> size is zero

        dc.SetFont(self.GetFont())
        if self.IsEnabled():
            dc.SetTextForeground(self.GetForegroundColour())
        else:
            dc.SetTextForeground(wx.SystemSettings.GetColour(wx.SYS_COLOUR_GRAYTEXT))

        label = self.GetLabel()
        tw, th = dc.GetTextExtent(label)        # size of text
        if not self.up:
            dw = dy = self.labelDelta

        pos_x = (width-bw)/2+dw      # adjust for bitmap and text to centre
        pos_y = (height-bh-th)/2+dy
        if bmp !=None:
            dc.DrawBitmap(bmp, pos_x, pos_y, hasMask) # draw bitmap if available
            pos_x = (width-tw)/2+dw      # adjust for bitmap and text to centre
            pos_y += bh + 2

        dc.DrawText(label, pos_x, pos_y)      # draw the text


class GenStaticBitmap(wx.lib.statbmp.GenStaticBitmap):
    """ Customized GenStaticBitmap, fix transparency redraw bug on wx2.8/win32, 
    and accept image name as __init__ parameter, fail silently if file do not exist"""
    def __init__(self, parent, ID, bitmapname,
                 pos = wx.DefaultPosition, size = wx.DefaultSize,
                 style = 0,
                 name = "genstatbmp"):
        
        wx.lib.statbmp.GenStaticBitmap.__init__(self, parent, ID, 
                 GetBitmap(bitmapname),
                 pos, size,
                 style,
                 name)
        
    def OnPaint(self, event):
        dc = wx.PaintDC(self)
        colour = self.GetParent().GetBackgroundColour()
        dc.SetPen(wx.Pen(colour))
        dc.SetBrush(wx.Brush(colour ))
        dc.DrawRectangle(0, 0, *dc.GetSizeTuple())
        if self._bitmap:
            dc.DrawBitmap(self._bitmap, 0, 0, True)

class ConfTreeNodeEditor(EditorPanel):
    
    SHOW_BASE_PARAMS = True
    SHOW_PARAMS = True
    
    def _init_ConfNodeEditor(self, prnt):
        self.ConfNodeEditor = None
    
    def _init_Editor(self, parent):
        self.Editor = wx.SplitterWindow(parent,
              style=wx.SUNKEN_BORDER|wx.SP_3D)
        self.SetNeedUpdating(True)
        self.SetMinimumPaneSize(1)
        
        if self.SHOW_PARAMS:
            self.ParamsEditor = wx.ScrolledWindow(self.Editor, 
                  style=wx.TAB_TRAVERSAL|wx.SUNKEN_BORDER|wx.HSCROLL|wx.VSCROLL)
            self.ParamsEditor.SetBackgroundColour(WINDOW_COLOUR)
            self.ParamsEditor.Bind(wx.EVT_SIZE, self.OnWindowResize)
            self.ParamsEditor.Bind(wx.EVT_MOUSEWHEEL, self.OnMouseWheel)
            
            # Variable allowing disabling of ParamsEditor scroll when Popup shown 
            self.ScrollingEnabled = True
            
            if self.SHOW_BASE_PARAMS:
                self.ParamsEditorSizer = wx.FlexGridSizer(cols=1, hgap=0, rows=2, vgap=5)
                self.ParamsEditorSizer.AddGrowableCol(0)
                self.ParamsEditorSizer.AddGrowableRow(1)
                
                self.ParamsEditor.SetSizer(self.ParamsEditorSizer)
                
                baseparamseditor_sizer = wx.BoxSizer(wx.HORIZONTAL)
                self.ParamsEditorSizer.AddSizer(baseparamseditor_sizer, border=5, 
                      flag=wx.GROW|wx.LEFT|wx.RIGHT|wx.TOP)
                
                self.FullIECChannel = wx.StaticText(self.ParamsEditor, -1)
                self.FullIECChannel.SetFont(
                    wx.Font(faces["size"], wx.DEFAULT, wx.NORMAL, 
                            wx.BOLD, faceName = faces["helv"]))
                baseparamseditor_sizer.AddWindow(self.FullIECChannel, 
                      flag=wx.ALIGN_CENTER_VERTICAL)
                
                updownsizer = wx.BoxSizer(wx.VERTICAL)
                baseparamseditor_sizer.AddSizer(updownsizer, border=5, 
                      flag=wx.LEFT|wx.ALIGN_CENTER_VERTICAL)
                
                self.IECCUpButton = wx.lib.buttons.GenBitmapTextButton(self.ParamsEditor, 
                      bitmap=GetBitmap('IECCDown'), size=wx.Size(16, 16), style=wx.NO_BORDER)
                self.IECCUpButton.Bind(wx.EVT_BUTTON, self.GetItemChannelChangedFunction(1), 
                      self.IECCUpButton)
                updownsizer.AddWindow(self.IECCUpButton, flag=wx.ALIGN_LEFT)
                
                self.IECCDownButton = wx.lib.buttons.GenBitmapButton(self.ParamsEditor, 
                      bitmap=GetBitmap('IECCUp'), size=wx.Size(16, 16), style=wx.NO_BORDER)
                self.IECCDownButton.Bind(wx.EVT_BUTTON, self.GetItemChannelChangedFunction(-1), 
                      self.IECCDownButton)
                updownsizer.AddWindow(self.IECCDownButton, flag=wx.ALIGN_LEFT)
                
                self.ConfNodeName = wx.TextCtrl(self.ParamsEditor, 
                      size=wx.Size(150, 25), style=wx.NO_BORDER)
                self.ConfNodeName.SetFont(
                    wx.Font(faces["size"] * 0.75, wx.DEFAULT, wx.NORMAL, 
                            wx.BOLD, faceName = faces["helv"]))
                self.ConfNodeName.Bind(wx.EVT_TEXT, 
                      self.GetTextCtrlCallBackFunction(self.ConfNodeName, "BaseParams.Name", True), 
                      self.ConfNodeName)
                baseparamseditor_sizer.AddWindow(self.ConfNodeName, border=5, 
                      flag=wx.LEFT|wx.RIGHT|wx.ALIGN_CENTER_VERTICAL)
                
                buttons_sizer = self.GenerateMethodButtonSizer()
                baseparamseditor_sizer.AddSizer(buttons_sizer, flag=wx.ALIGN_CENTER)
            
            else:
                self.ParamsEditorSizer = wx.FlexGridSizer(cols=1, hgap=0, rows=1, vgap=5)
                self.ParamsEditorSizer.AddGrowableCol(0)
                self.ParamsEditorSizer.AddGrowableRow(0)
            
            self.ConfNodeParamsSizer = wx.BoxSizer(wx.VERTICAL)
            self.ParamsEditorSizer.AddSizer(self.ConfNodeParamsSizer, border=5, 
                  flag=wx.LEFT|wx.RIGHT|wx.BOTTOM)
            
            self.RefreshConfNodeParamsSizer()
        else:
            self.ParamsEditor = None
        
        self._init_ConfNodeEditor(self.Editor)
            
        if self.ConfNodeEditor is not None:
            if self.ParamsEditor is not None:
                min_size = self.ParamsEditorSizer.GetMinSize()
                self.Editor.SplitHorizontally(self.ParamsEditor, 
                                              self.ConfNodeEditor, 
                                              min(min_size.height, 200))
            else:
                self.Editor.Initialize(self.ConfNodeEditor)
        elif self.ParamsEditor is not None:
            self.Editor.Initialize(self.ParamsEditor)
    
    def __init__(self, parent, controler, window, tagname=""):
        EditorPanel.__init__(self, parent, tagname, window, controler)
        
        icon_name = self.Controler.GetIconName()
        if icon_name is not None:
            self.SetIcon(GetBitmap(icon_name))
        else:
            self.SetIcon(GetBitmap("Extension"))
        
    def __del__(self):
        self.Controler.OnCloseEditor(self)
    
    def GetTagName(self):
        return self.Controler.CTNFullName()
    
    def GetTitle(self):
        fullname = self.Controler.CTNFullName()
        if self.Controler.CTNTestModified():
            return "~%s~" % fullname
        return fullname
    
    def HasNoModel(self):
        return False
    
    def GetBufferState(self):
        return False, False
    
    def Undo(self):
        pass
    
    def Redo(self):
        pass
    
    def RefreshView(self):
        EditorPanel.RefreshView(self)
        if self.ParamsEditor is not None:
            if self.SHOW_BASE_PARAMS:
                self.ConfNodeName.ChangeValue(self.Controler.MandatoryParams[1].getName())
                self.RefreshIECChannelControlsState()
            self.RefreshConfNodeParamsSizer()
            self.RefreshScrollbars()
    
    def EnableScrolling(self, enable):
        self.ScrollingEnabled = enable
    
    def RefreshIECChannelControlsState(self):
        self.FullIECChannel.SetLabel(self.Controler.GetFullIEC_Channel())
        self.IECCDownButton.Enable(self.Controler.BaseParams.getIEC_Channel() > 0)
    
    def RefreshConfNodeParamsSizer(self):
        self.Freeze()
        self.ConfNodeParamsSizer.Clear(True)
        
        confnode_infos = self.Controler.GetParamsAttributes()
        if len(confnode_infos) > 0:
            self.GenerateSizerElements(self.ConfNodeParamsSizer, confnode_infos, None, False)
        
        self.ParamsEditorSizer.Layout()
        self.Thaw()
    
    def GenerateMethodButtonSizer(self):
        normal_bt_font=wx.Font(faces["size"] / 3, wx.DEFAULT, wx.NORMAL, wx.NORMAL, faceName = faces["helv"])
        mouseover_bt_font=wx.Font(faces["size"] / 3, wx.DEFAULT, wx.NORMAL, wx.NORMAL, underline=True, faceName = faces["helv"])
        
        msizer = wx.BoxSizer(wx.HORIZONTAL)
        
        for confnode_method in self.Controler.ConfNodeMethods:
            if "method" in confnode_method and confnode_method.get("shown",True):
                button = GenBitmapTextButton(self.ParamsEditor,
                    bitmap=GetBitmap(confnode_method.get("bitmap", "Unknown")), 
                    label=confnode_method["name"], style=wx.NO_BORDER)
                button.SetFont(normal_bt_font)
                button.SetToolTipString(confnode_method["tooltip"])
                if confnode_method.get("push", False):
                    button.Bind(wx.EVT_LEFT_DOWN, self.GetButtonCallBackFunction(confnode_method["method"], True))
                else:
                    button.Bind(wx.EVT_BUTTON, self.GetButtonCallBackFunction(confnode_method["method"]), button)
                # a fancy underline on mouseover
                def setFontStyle(b, s):
                    def fn(event):
                        b.SetFont(s)
                        b.Refresh()
                        event.Skip()
                    return fn
                button.Bind(wx.EVT_ENTER_WINDOW, setFontStyle(button, mouseover_bt_font))
                button.Bind(wx.EVT_LEAVE_WINDOW, setFontStyle(button, normal_bt_font))
                #hack to force size to mini
                if not confnode_method.get("enabled",True):
                    button.Disable()
                msizer.AddWindow(button, flag=wx.ALIGN_CENTER)
        return msizer
    
    def GenerateSizerElements(self, sizer, elements, path, clean = True):
        if clean:
            sizer.Clear(True)
        first = True
        for element_infos in elements:
            if path:
                element_path = "%s.%s"%(path, element_infos["name"])
            else:
                element_path = element_infos["name"]
            if element_infos["type"] == "element":
                label = element_infos["name"]
                staticbox = wx.StaticBox(self.ParamsEditor, 
                      label=_(label), size=wx.Size(10, 0))
                staticboxsizer = wx.StaticBoxSizer(staticbox, wx.VERTICAL)
                if first:
                    sizer.AddSizer(staticboxsizer, border=5, 
                          flag=wx.GROW|wx.TOP|wx.BOTTOM)
                else:
                    sizer.AddSizer(staticboxsizer, border=5, 
                          flag=wx.GROW|wx.BOTTOM)
                self.GenerateSizerElements(staticboxsizer, 
                                           element_infos["children"], 
                                           element_path)
            else:
                boxsizer = wx.FlexGridSizer(cols=3, rows=1)
                boxsizer.AddGrowableCol(1)
                if first:
                    sizer.AddSizer(boxsizer, border=5, 
                          flag=wx.GROW|wx.ALL)
                else:
                    sizer.AddSizer(boxsizer, border=5, 
                          flag=wx.GROW|wx.LEFT|wx.RIGHT|wx.BOTTOM)
                
                staticbitmap = GenStaticBitmap(ID=-1, bitmapname=element_infos["name"],
                    name="%s_bitmap"%element_infos["name"], parent=self.ParamsEditor,
                    pos=wx.Point(0, 0), size=wx.Size(24, 24), style=0)
                boxsizer.AddWindow(staticbitmap, border=5, flag=wx.RIGHT)
                
                statictext = wx.StaticText(self.ParamsEditor, 
                      label="%s:"%_(element_infos["name"]))
                boxsizer.AddWindow(statictext, border=5, 
                      flag=wx.ALIGN_CENTER_VERTICAL|wx.RIGHT)
                
                if isinstance(element_infos["type"], types.ListType):
                    if isinstance(element_infos["value"], types.TupleType):
                        browse_boxsizer = wx.BoxSizer(wx.HORIZONTAL)
                        boxsizer.AddSizer(browse_boxsizer)
                        
                        textctrl = wx.TextCtrl(self.ParamsEditor, 
                              size=wx.Size(275, -1), style=wx.TE_READONLY)
                        if element_infos["value"] is not None:
                            textctrl.SetValue(element_infos["value"][0])
                            value_infos = element_infos["value"][1]
                        else:
                            value_infos = None
                        browse_boxsizer.AddWindow(textctrl)
                        
                        button = wx.Button(self.ParamsEditor, 
                              label="...", size=wx.Size(25, 25))
                        browse_boxsizer.AddWindow(button)
                        button.Bind(wx.EVT_BUTTON, 
                                    self.GetBrowseCallBackFunction(element_infos["name"], textctrl, element_infos["type"], 
                                                                   value_infos, element_path), 
                                    button)
                    else:
                        combobox = wx.ComboBox(self.ParamsEditor, 
                              size=wx.Size(300, -1), style=wx.CB_READONLY)
                        boxsizer.AddWindow(combobox)
                        
                        if element_infos["use"] == "optional":
                            combobox.Append("")
                        if len(element_infos["type"]) > 0 and isinstance(element_infos["type"][0], types.TupleType):
                            for choice, xsdclass in element_infos["type"]:
                                combobox.Append(choice)
                            name = element_infos["name"]
                            value = element_infos["value"]
                        
                            staticbox = wx.StaticBox(self.ParamsEditor, 
                                  label="%s - %s"%(_(name), _(value)), size=wx.Size(10, 0))
                            staticboxsizer = wx.StaticBoxSizer(staticbox, wx.VERTICAL)
                            sizer.AddSizer(staticboxsizer, border=5, flag=wx.GROW|wx.BOTTOM)
                            self.GenerateSizerElements(staticboxsizer, element_infos["children"], element_path)
                            callback = self.GetChoiceContentCallBackFunction(combobox, staticboxsizer, element_path)
                        else:
                            for choice in element_infos["type"]:
                                combobox.Append(choice)
                            callback = self.GetChoiceCallBackFunction(combobox, element_path)
                        if element_infos["value"] is None:
                            combobox.SetStringSelection("")
                        else:
                            combobox.SetStringSelection(element_infos["value"])
                        combobox.Bind(wx.EVT_COMBOBOX, callback, combobox)
                
                elif isinstance(element_infos["type"], types.DictType):
                    scmin = -(2**31)
                    scmax = 2**31-1
                    if "min" in element_infos["type"]:
                        scmin = element_infos["type"]["min"]
                    if "max" in element_infos["type"]:
                        scmax = element_infos["type"]["max"]
                    spinctrl = wx.SpinCtrl(self.ParamsEditor, 
                          size=wx.Size(300, -1), style=wx.SP_ARROW_KEYS|wx.ALIGN_RIGHT)
                    spinctrl.SetRange(scmin, scmax)
                    boxsizer.AddWindow(spinctrl)
                    if element_infos["value"] is not None:
                        spinctrl.SetValue(element_infos["value"])
                    spinctrl.Bind(wx.EVT_SPINCTRL, 
                                  self.GetTextCtrlCallBackFunction(spinctrl, element_path),
                                  spinctrl)
                
                else:
                    if element_infos["type"] == "boolean":
                        checkbox = wx.CheckBox(self.ParamsEditor, size=wx.Size(17, 25))
                        boxsizer.AddWindow(checkbox)
                        if element_infos["value"] is not None:
                            checkbox.SetValue(element_infos["value"])
                        checkbox.Bind(wx.EVT_CHECKBOX, 
                                      self.GetCheckBoxCallBackFunction(checkbox, element_path), 
                                      checkbox)
                    
                    elif element_infos["type"] in ["unsignedLong", "long","integer"]:
                        if element_infos["type"].startswith("unsigned"):
                            scmin = 0
                        else:
                            scmin = -(2**31)
                        scmax = 2**31-1
                        spinctrl = wx.SpinCtrl(self.ParamsEditor, 
                              size=wx.Size(300, -1), style=wx.SP_ARROW_KEYS|wx.ALIGN_RIGHT)
                        spinctrl.SetRange(scmin, scmax)
                        boxsizer.AddWindow(spinctrl)
                        if element_infos["value"] is not None:
                            spinctrl.SetValue(element_infos["value"])
                        spinctrl.Bind(wx.EVT_SPINCTRL, 
                                      self.GetTextCtrlCallBackFunction(spinctrl, element_path), 
                                      spinctrl)
                    
                    else:
                        choices = self.ParentWindow.GetConfigEntry(element_path, [""])
                        textctrl = TextCtrlAutoComplete(name=element_infos["name"], 
                                                        parent=self.ParamsEditor, 
                                                        appframe=self, 
                                                        choices=choices, 
                                                        element_path=element_path,
                                                        size=wx.Size(300, -1))
                        
                        boxsizer.AddWindow(textctrl)
                        if element_infos["value"] is not None:
                            textctrl.ChangeValue(str(element_infos["value"]))
                        textctrl.Bind(wx.EVT_TEXT, self.GetTextCtrlCallBackFunction(textctrl, element_path))
            first = False
    
    
    def GetItemChannelChangedFunction(self, dir):
        def OnConfNodeTreeItemChannelChanged(event):
            confnode_IECChannel = self.Controler.BaseParams.getIEC_Channel()
            res = self.SetConfNodeParamsAttribute("BaseParams.IEC_Channel", confnode_IECChannel + dir)
            wx.CallAfter(self.RefreshIECChannelControlsState)
            wx.CallAfter(self.ParentWindow._Refresh, TITLE, FILEMENU, PROJECTTREE)
            wx.CallAfter(self.ParentWindow.SelectProjectTreeItem, self.GetTagName())
            event.Skip()
        return OnConfNodeTreeItemChannelChanged
    
    def SetConfNodeParamsAttribute(self, *args, **kwargs):
        res, StructChanged = self.Controler.SetParamsAttribute(*args, **kwargs)
        if StructChanged:
            wx.CallAfter(self.RefreshConfNodeParamsSizer)
        wx.CallAfter(self.ParentWindow._Refresh, TITLE, FILEMENU)
        return res
    
    def GetButtonCallBackFunction(self, method, push=False):
        """ Generate the callbackfunc for a given confnode method"""
        def OnButtonClick(event):
            # Disable button to prevent re-entrant call 
            event.GetEventObject().Disable()
            # Call
            getattr(self.Controler,method)()
            # Re-enable button 
            event.GetEventObject().Enable()
            
            if not push:
                event.Skip()
        return OnButtonClick
    
    def GetChoiceCallBackFunction(self, choicectrl, path):
        def OnChoiceChanged(event):
            res = self.SetConfNodeParamsAttribute(path, choicectrl.GetStringSelection())
            choicectrl.SetStringSelection(res)
            event.Skip()
        return OnChoiceChanged
    
    def GetChoiceContentCallBackFunction(self, choicectrl, staticboxsizer, path):
        def OnChoiceContentChanged(event):
            res = self.SetConfNodeParamsAttribute(path, choicectrl.GetStringSelection())
            wx.CallAfter(self.RefreshConfNodeParamsSizer)
            event.Skip()
        return OnChoiceContentChanged
    
    def GetTextCtrlCallBackFunction(self, textctrl, path, refresh=False):
        def OnTextCtrlChanged(event):
            res = self.SetConfNodeParamsAttribute(path, textctrl.GetValue())
            if res != textctrl.GetValue():
                if isinstance(textctrl, wx.SpinCtrl):
                    textctrl.SetValue(res)
                else:
                    textctrl.ChangeValue(res)
            if refresh:
                wx.CallAfter(self.ParentWindow._Refresh, TITLE, FILEMENU, PROJECTTREE, PAGETITLES)
                wx.CallAfter(self.ParentWindow.SelectProjectTreeItem, self.GetTagName())
            event.Skip()
        return OnTextCtrlChanged
    
    def GetCheckBoxCallBackFunction(self, chkbx, path):
        def OnCheckBoxChanged(event):
            res = self.SetConfNodeParamsAttribute(path, chkbx.IsChecked())
            chkbx.SetValue(res)
            event.Skip()
        return OnCheckBoxChanged
    
    def GetBrowseCallBackFunction(self, name, textctrl, library, value_infos, path):
        infos = [value_infos]
        def OnBrowseButton(event):
            dialog = BrowseValuesLibraryDialog(self, name, library, infos[0])
            if dialog.ShowModal() == wx.ID_OK:
                value, value_infos = self.SetConfNodeParamsAttribute(path, dialog.GetValueInfos())
                textctrl.ChangeValue(value)
                infos[0] = value_infos
            dialog.Destroy()
            event.Skip()
        return OnBrowseButton
    
    def RefreshScrollbars(self):
        self.ParamsEditor.GetBestSize()
        xstart, ystart = self.ParamsEditor.GetViewStart()
        window_size = self.ParamsEditor.GetClientSize()
        maxx, maxy = self.ParamsEditorSizer.GetMinSize()
        posx = max(0, min(xstart, (maxx - window_size[0]) / SCROLLBAR_UNIT))
        posy = max(0, min(ystart, (maxy - window_size[1]) / SCROLLBAR_UNIT))
        self.ParamsEditor.Scroll(posx, posy)
        self.ParamsEditor.SetScrollbars(SCROLLBAR_UNIT, SCROLLBAR_UNIT, 
                maxx / SCROLLBAR_UNIT, maxy / SCROLLBAR_UNIT, posx, posy)
    
    def OnWindowResize(self, event):
        self.RefreshScrollbars()
        event.Skip()
    
    def OnMouseWheel(self, event):
        if self.ScrollingEnabled:
            event.Skip()