import  sys
import  wx

py2 = sys.version[0] == '2'

try:
    if py2:
        from xml.parsers import expat
        parsermodule = expat
    else:
        from xml.parsers import pyexpat
        parsermodule = pyexpat
    haveXML = True
except ImportError:
    haveXML = False

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

if not haveXML:
    def runTest(frame, nb, log):
        dlg = wx.MessageDialog(
                frame, 'This demo requires the XML package.  '
                'See http://www.python.org/sigs/xml-sig/',
                'Sorry', wx.OK | wx.ICON_INFORMATION
                )

        dlg.ShowModal()
        dlg.Destroy()

else:

    class XMLTree(wx.TreeCtrl):
        def __init__(self, parent, ID):
            wx.TreeCtrl.__init__(self, parent, ID)
            self._root = self.AddRoot("Root")
            self.nodeStack = [self._root]

            # Trees need an image list to do DnD...
            self.il = wx.ImageList(16,16)
            self.SetImageList(self.il)

            # event handlers for DnD
            self.Bind(wx.EVT_TREE_BEGIN_DRAG, self.OnBeginDrag)
            self.Bind(wx.EVT_TREE_END_DRAG, self.OnEndDrag)


        def OnBeginDrag(self, event):
            item = event.GetItem()

            if item != self.GetRootItem():
                self.draggingItem = item
                event.Allow()  # if DnD of this item is okay Allow it.

        def IsDescendant(self, firstItem, secondItem):
            "Recursive check if firstItem is a descendant of a secondItem."
            if firstItem == self._root:
                return False
            parentItem = self.GetItemParent(firstItem)
            if parentItem == secondItem:
                return True
            else:
                return self.IsDescendant(parentItem, secondItem)

        def OnEndDrag(self, evt):
            itemSrc = self.draggingItem
            itemDst = evt.GetItem()
            self.draggingItem = None

            if not itemDst.IsOk():
                print "Can't drag to here..."
                return

            if self.IsDescendant(itemDst, itemSrc):
                print "Can't move item to its descendant"
                return

            # For this simple example just take the text of the source item
            # and append it to the destination item.  In real life you would
            # possibly want to copy subtrees...
            text = self.GetItemText(itemSrc)
            self.AppendItem(itemDst, text)
            self.Delete(itemSrc)


        # Define a handler for start element events
        def StartElement(self, name, attrs ):
            if py2:
                name = name.encode()

            id = self.AppendItem(self.nodeStack[-1], name)
            self.nodeStack.append(id)

        def EndElement(self,  name ):
            self.nodeStack = self.nodeStack[:-1]

        def CharacterData(self, data ):
            if data.strip():
                if py2:
                    data = data.encode()

                self.AppendItem(self.nodeStack[-1], data)


        def LoadTree(self, filename):
            # Create a parser
            Parser = parsermodule.ParserCreate()

            # Tell the parser what the start element handler is
            Parser.StartElementHandler = self.StartElement
            Parser.EndElementHandler = self.EndElement
            Parser.CharacterDataHandler = self.CharacterData

            # Parse the XML File
            ParserStatus = Parser.Parse(open(filename,'r').read(), 1)


    def runTest(frame, nb, log):
        win = XMLTree(nb, -1)
        win.LoadTree("paper.xml")
        return win

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



overview = """\
"""


if __name__ == '__main__':
    import sys,os
    import run
    run.main(['', os.path.basename(sys.argv[0])] + sys.argv[1:])