#! /usr/bin/env python
import wx, sys, os, logging, operator
import wx.lib.newevent
log = logging.getLogger( 'squaremap' )
#log.setLevel( logging.DEBUG )

SquareHighlightEvent, EVT_SQUARE_HIGHLIGHTED = wx.lib.newevent.NewEvent()
SquareSelectionEvent, EVT_SQUARE_SELECTED = wx.lib.newevent.NewEvent()
SquareActivationEvent, EVT_SQUARE_ACTIVATED = wx.lib.newevent.NewEvent()


class HotMapNavigator(object):
    ''' Utility class for navigating the hot map and finding nodes. '''

    @classmethod
    def findNode(class_, hot_map, targetNode, parentNode=None):
        ''' Find the target node in the hot_map. '''
        for index, (rect, node, children) in enumerate(hot_map):
            if node == targetNode:
                return parentNode, hot_map, index
            result = class_.findNode(children, targetNode, node)
            if result:
                return result
        return None

    if hasattr( wx.Rect, 'Contains' ):
        # wx 2.8+
        @classmethod
        def findNodeAtPosition(class_, hot_map, position, parent=None):
            ''' Retrieve the node at the given position. '''
            for rect, node, children in hot_map:
                if rect.Contains(position):
                    return class_.findNodeAtPosition(children, position, node)
            return parent
    else:
        # wx 2.6
        @classmethod
        def findNodeAtPosition(class_, hot_map, position, parent=None):
            ''' Retrieve the node at the given position. '''
            for rect, node, children in hot_map:
                if rect.Inside(position):
                    return class_.findNodeAtPosition(children, position, node)
            return parent

    @staticmethod
    def firstChild(hot_map, index):
        ''' Return the first child of the node indicated by index. '''
        children = hot_map[index][2]
        if children:
            return children[0][1]
        else:
            return hot_map[index][1] # No children, return the node itself

    @staticmethod
    def nextChild(hotmap, index):
        ''' Return the next sibling of the node indicated by index. '''
        nextChildIndex = min(index + 1, len(hotmap) - 1)
        return hotmap[nextChildIndex][1]

    @staticmethod
    def previousChild(hotmap, index):
        ''' Return the previous sibling of the node indicated by index. '''
        previousChildIndex = max(0, index - 1)
        return hotmap[previousChildIndex][1]

    @staticmethod
    def firstNode(hot_map):
        ''' Return the very first node in the hot_map. '''
        return hot_map[0][1]

    @classmethod
    def lastNode(class_, hot_map):
        ''' Return the very last node (recursively) in the hot map. '''
        children = hot_map[-1][2]
        if children:
            return class_.lastNode(children)
        else:
            return hot_map[-1][1] # Return the last node


class SquareMap( wx.Panel ):
    """Construct a nested-box trees structure view"""

    BackgroundColour = wx.Colour( 128,128,128 )
    max_depth = None
    max_depth_seen = None

    def __init__(
        self,  parent=None, id=-1, pos=wx.DefaultPosition,
        size=wx.DefaultSize,
        style=wx.TAB_TRAVERSAL|wx.NO_BORDER|wx.FULL_REPAINT_ON_RESIZE,
        name='SquareMap', model = None,
        adapter = None,
        labels = True, 
        highlight = True,
        padding = 2,
        margin = 0,
        square_style = False,
    ):
        """Initialise the SquareMap
        
        adapter -- a DefaultAdapter or same-interface instance providing SquareMap data api
        labels -- set to True (default) to draw textual labels within the boxes
        highlight -- set to True (default) to highlight nodes on mouse-over 
        padding -- spacing within each square and its children (within the square's border)
        margin -- spacing around each square (on all sides)
        square_style -- use a more-recursive, less-linear, more "square" layout style which 
            works better on objects with large numbers of children, such as Meliae memory 
            dumps, works fine on profile views as well, but the layout is less obvious wrt 
            what node is "next" "previous" etc.
        """
        super( SquareMap, self ).__init__(
            parent, id, pos, size, style, name
        )
        self.model = model
        self.padding = padding
        self.square_style = square_style
        self.margin = margin
        self.labels = labels
        self.highlight = highlight
        self.selectedNode = None
        self.highlightedNode = None
        self._buffer = wx.EmptyBitmap(20, 20) # Have a default buffer ready
        self.Bind( wx.EVT_PAINT, self.OnPaint)
        self.Bind( wx.EVT_SIZE, self.OnSize )
        if highlight:
            self.Bind( wx.EVT_MOTION, self.OnMouse )
        self.Bind( wx.EVT_LEFT_UP, self.OnClickRelease )
        self.Bind( wx.EVT_LEFT_DCLICK, self.OnDoubleClick )
        self.Bind( wx.EVT_KEY_UP, self.OnKeyUp )
        self.hot_map = []
        self.adapter = adapter or DefaultAdapter()
        self.DEFAULT_PEN = wx.Pen( wx.BLACK, 1, wx.SOLID )
        self.SELECTED_PEN = wx.Pen( wx.WHITE, 2, wx.SOLID )
        self.OnSize(None)

    def OnMouse( self, event ):
        """Handle mouse-move event by selecting a given element"""
        node = HotMapNavigator.findNodeAtPosition(self.hot_map, event.GetPosition())
        self.SetHighlight( node, event.GetPosition() )

    def OnClickRelease( self, event ):
        """Release over a given square in the map"""
        node = HotMapNavigator.findNodeAtPosition(self.hot_map, event.GetPosition())
        self.SetSelected( node, event.GetPosition() )

    def OnDoubleClick(self, event):
        """Double click on a given square in the map"""
        node = HotMapNavigator.findNodeAtPosition(self.hot_map, event.GetPosition())
        if node:
            wx.PostEvent( self, SquareActivationEvent( node=node, point=event.GetPosition(), map=self ) )

    def OnKeyUp(self, event):
        event.Skip()
        if not self.selectedNode or not self.hot_map:
            return

        if event.KeyCode == wx.WXK_HOME:
            self.SetSelected(HotMapNavigator.firstNode(self.hot_map))
            return
        elif event.KeyCode == wx.WXK_END:
            self.SetSelected(HotMapNavigator.lastNode(self.hot_map))
            return

        try:
            parent, children, index = HotMapNavigator.findNode(self.hot_map, self.selectedNode)
        except TypeError:
            log.info( 'Unable to find hot-map record for node %s', self.selectedNode )
        else:
            if event.KeyCode == wx.WXK_DOWN:
                self.SetSelected(HotMapNavigator.nextChild(children, index))
            elif event.KeyCode == wx.WXK_UP:
                self.SetSelected(HotMapNavigator.previousChild(children, index))
            elif event.KeyCode == wx.WXK_RIGHT:
                self.SetSelected(HotMapNavigator.firstChild(children, index))
            elif event.KeyCode == wx.WXK_LEFT and parent:
                self.SetSelected(parent)
            elif event.KeyCode == wx.WXK_RETURN:
                wx.PostEvent(self, SquareActivationEvent(node=self.selectedNode,
                                                         map=self))

    def GetSelected(self):
        return self.selectedNode

    def SetSelected( self, node, point=None, propagate=True ):
        """Set the given node selected in the square-map"""
        if node == self.selectedNode:
            return
        self.selectedNode = node
        self.UpdateDrawing()
        if node:
            wx.PostEvent( self, SquareSelectionEvent( node=node, point=point, map=self ) )

    def SetHighlight( self, node, point=None, propagate=True ):
        """Set the currently-highlighted node"""
        if node == self.highlightedNode:
            return
        self.highlightedNode = node
        # TODO: restrict refresh to the squares for previous node and new node...
        self.UpdateDrawing()
        if node and propagate:
            wx.PostEvent( self, SquareHighlightEvent( node=node, point=point, map=self ) )

    def SetModel( self, model, adapter=None ):
        """Set our model object (root of the tree)"""
        self.model = model
        if adapter is not None:
            self.adapter = adapter
        self.UpdateDrawing()

    def OnPaint(self, event):
        dc = wx.BufferedPaintDC(self, self._buffer)

    def OnSize(self, event):
        # The buffer is initialized in here, so that the buffer is always
        # the same size as the Window.
        if event is None:
            return 0,0
        width, height = self.GetClientSizeTuple()
        if width <= 0 or height <=0:
            return 0,0
        # Make new off-screen bitmap: this bitmap will always have the
        # current drawing in it, so it can be used to save the image to
        # a file, or whatever.
        if width and height:
            # Macs can generate events with 0-size values
            self._buffer = wx.EmptyBitmap(width, height)
            self.UpdateDrawing()

    def UpdateDrawing(self):
        dc = wx.BufferedDC(wx.ClientDC(self), self._buffer)
        self.Draw(dc)

    def Draw(self, dc):
        ''' Draw the tree map on the device context. '''
        self.hot_map = []
        dc.BeginDrawing()
        brush = wx.Brush( self.BackgroundColour  )
        dc.SetBackground( brush )
        dc.Clear()
        if self.model:
            self.max_depth_seen = 0
            font = self.FontForLabels(dc)
            dc.SetFont(font)
            self._em_size_ = dc.GetFullTextExtent( 'm', font )[0]
            w, h = dc.GetSize()
            self.DrawBox( dc, self.model, 0,0,w,h, hot_map = self.hot_map )
        dc.EndDrawing()

    def FontForLabels(self, dc):
        ''' Return the default GUI font, scaled for printing if necessary. '''
        font = wx.SystemSettings_GetFont(wx.SYS_DEFAULT_GUI_FONT)
        scale = dc.GetPPI()[0] / wx.ScreenDC().GetPPI()[0]
        font.SetPointSize(scale*font.GetPointSize())
        return font

    def BrushForNode( self, node, depth=0 ):
        """Create brush to use to display the given node"""
        if node == self.selectedNode:
            colour = wx.SystemSettings_GetColour(wx.SYS_COLOUR_HIGHLIGHT)
        elif node == self.highlightedNode:
            colour = wx.Colour( red=0, green=255, blue=0 )
        else:
            colour = self.adapter.background_color(node, depth)
            if not colour:
                red = (depth * 10)%255
                green = 255-((depth * 5)%255)
                blue = (depth * 25)%255
                colour = wx.Colour( red, green, blue )
        return wx.Brush( colour  )

    def PenForNode( self, node, depth=0 ):
        """Determine the pen to use to display the given node"""
        if node == self.selectedNode:
            return self.SELECTED_PEN
        return self.DEFAULT_PEN

    def TextForegroundForNode(self, node, depth=0):
        """Determine the text foreground colour to use to display the label of
           the given node"""
        if node == self.selectedNode:
            fg_colour = wx.SystemSettings_GetColour(wx.SYS_COLOUR_HIGHLIGHTTEXT)
        else:
            fg_colour = self.adapter.foreground_color(node, depth)
            if not fg_colour:
                fg_colour = wx.SystemSettings_GetColour(wx.SYS_COLOUR_WINDOWTEXT)
        return fg_colour

    def DrawBox( self, dc, node, x,y,w,h, hot_map, depth=0 ):
        """Draw a model-node's box and all children nodes"""
        log.debug( 'Draw: %s to (%s,%s,%s,%s) depth %s',
            node, x,y,w,h, depth,
        )
        if self.max_depth and depth > self.max_depth:
            return
        self.max_depth_seen = max( (self.max_depth_seen,depth))
        dc.SetBrush( self.BrushForNode( node, depth ) )
        dc.SetPen( self.PenForNode( node, depth ) )
        # drawing offset by margin within the square...
        dx,dy,dw,dh = x+self.margin,y+self.margin,w-(self.margin*2),h-(self.margin*2)
        if sys.platform == 'darwin':
            # Macs don't like drawing small rounded rects...
            if w < self.padding*2 or h < self.padding*2:
                dc.DrawRectangle( dx,dy,dw,dh )
            else:
                dc.DrawRoundedRectangle( dx,dy,dw,dh, self.padding )
        else:
            dc.DrawRoundedRectangle( dx,dy,dw,dh, self.padding*3 )
#        self.DrawIconAndLabel(dc, node, x, y, w, h, depth)
        children_hot_map = []
        hot_map.append( (wx.Rect( int(x),int(y),int(w),int(h)), node, children_hot_map ) )
        x += self.padding
        y += self.padding
        w -= self.padding*2
        h -= self.padding*2
        

        empty = self.adapter.empty( node )
        icon_drawn = False
        if self.max_depth and depth == self.max_depth:
            self.DrawIconAndLabel(dc, node, x, y, w, h, depth)
            icon_drawn = True
        elif empty:
            # is a fraction of the space which is empty...
            log.debug( '  empty space fraction: %s', empty )
            new_h = h * (1.0-empty)
            self.DrawIconAndLabel(dc, node, x, y, w, h-new_h, depth)
            icon_drawn = True
            y += (h-new_h)
            h = new_h

        if w >self.padding*2 and h> self.padding*2:
            children = self.adapter.children( node )
            if children:
                log.debug( '  children: %s', children )
                self.LayoutChildren( dc, children, node, x,y,w,h, children_hot_map, depth+1 )
            else:
                log.debug( '  no children' )
                if not icon_drawn:
                    self.DrawIconAndLabel(dc, node, x, y, w, h, depth)
        else:
            log.debug( '  not enough space: children skipped' )

    def DrawIconAndLabel(self, dc, node, x, y, w, h, depth):
        ''' Draw the icon, if any, and the label, if any, of the node. '''
        if w-2 < self._em_size_//2 or h-2 < self._em_size_ //2:
            return
        dc.SetClippingRegion(x+1, y+1, w-2, h-2) # Don't draw outside the box
        try:
            icon = self.adapter.icon(node, node==self.selectedNode)
            if icon and h >= icon.GetHeight() and w >= icon.GetWidth():
                iconWidth = icon.GetWidth() + 2
                dc.DrawIcon(icon, x+2, y+2)
            else:
                iconWidth = 0
            if self.labels and h >= dc.GetTextExtent('ABC')[1]:
                dc.SetTextForeground(self.TextForegroundForNode(node, depth))
                dc.DrawText(self.adapter.label(node), x + iconWidth + 2, y+2)
        finally:
            dc.DestroyClippingRegion()
    def LayoutChildren( self, dc, children, parent, x,y,w,h, hot_map, depth=0, node_sum=None ):
        """Layout the set of children in the given rectangle
        
        node_sum -- if provided, we are a recursive call that already has sizes and sorting,
            so skip those operations
        """
        if node_sum is None:
            nodes = [ (self.adapter.value(node,parent),node) for node in children ]
            nodes.sort(key=operator.itemgetter(0))
            total = self.adapter.children_sum( children,parent )
        else:
            nodes = children
            total = node_sum
        if total:
            if self.square_style and len(nodes) > 5:
                # new handling to make parents with large numbers of parents a little less 
                # "sliced" looking (i.e. more square)
                (head_sum,head),(tail_sum,tail) = split_by_value( total, nodes )
                if head and tail:
                    # split into two sub-boxes and render each...
                    head_coord,tail_coord = split_box( head_sum/float(total), x,y,w,h )
                    if head_coord:
                        self.LayoutChildren( 
                            dc, head, parent, head_coord[0],head_coord[1],head_coord[2],head_coord[3],
                            hot_map, depth,
                            node_sum = head_sum,
                        )
                    if tail_coord and coord_bigger_than_padding( tail_coord, self.padding+self.margin ):
                        self.LayoutChildren( 
                            dc, tail, parent, tail_coord[0],tail_coord[1],tail_coord[2],tail_coord[3],
                            hot_map, depth,
                            node_sum = tail_sum,
                        )
                    return 
                        
            (firstSize,firstNode) = nodes[-1]
            fraction = firstSize/float(total)
            head_coord,tail_coord = split_box( firstSize/float(total), x,y,w,h )
            if head_coord:
                self.DrawBox( 
                    dc, firstNode, head_coord[0],head_coord[1],head_coord[2],head_coord[3], 
                    hot_map, depth
                )
            else:
                return # no other node will show up as non-0 either
                
            if len(nodes) > 1 and tail_coord and coord_bigger_than_padding( tail_coord, self.padding+self.margin ):
                self.LayoutChildren( 
                    dc, nodes[:-1], parent, 
                    tail_coord[0],tail_coord[1],tail_coord[2],tail_coord[3], 
                    hot_map, depth,
                    node_sum = total - firstSize,
                )
def coord_bigger_than_padding( tail_coord, padding ):
    return (
        tail_coord and 
        tail_coord[2] > padding * 2 and 
        tail_coord[3] > padding * 2
    )
def split_box( fraction, x,y, w,h ):
    """Return set of two boxes where first is the fraction given"""
    if w >= h:
        new_w = int(w*fraction)
        if new_w:
            return (x,y,new_w,h),(x+new_w,y,w-new_w,h)
        else:
            return None,None
    else:
        new_h = int(h*fraction)
        if new_h:
            return (x,y,w,new_h),(x,y+new_h,w,h-new_h)
        else:
            return None,None
    
def split_by_value( total, nodes, headdivisor=2.0 ):
    """Produce, (sum,head),(sum,tail) for nodes to attempt binary partition"""
    head_sum,tail_sum = 0,0
    divider = 0
    for node in nodes[::-1]:
        if head_sum < total/headdivisor:
            head_sum += node[0]
            divider -= 1
        else:
            break
    return (head_sum,nodes[divider:]),(total-head_sum,nodes[:divider])


class DefaultAdapter( object ):
    """Default adapter class for adapting node-trees to SquareMap API"""
    def children( self, node ):
        """Retrieve the set of nodes which are children of this node"""
        return node.children
    def value( self, node, parent=None ):
        """Return value used to compare size of this node"""
        return node.size
    def label( self, node ):
        """Return textual description of this node"""
        return node.path
    def overall( self, node ):
        """Calculate overall size of the node including children and empty space"""
        return sum( [self.value(value,node) for value in self.children(node)] )
    def children_sum( self, children,node ):
        """Calculate children's total sum"""
        return sum( [self.value(value,node) for value in children] )
    def empty( self, node ):
        """Calculate empty space as a fraction of total space"""
        overall = self.overall( node )
        if overall:
            return (overall - self.children_sum( self.children(node), node))/float(overall)
        return 0
    def background_color(self, node, depth):
        ''' The color to use as background color of the node. '''
        return None
    def foreground_color(self, node, depth):
        ''' The color to use for the label. '''
        return None
    def icon(self, node, isSelected):
        ''' The icon to display in the node. '''
        return None
    def parents( self, node ):
        """Retrieve/calculate the set of parents for the given node"""
        return []


class TestApp(wx.App):
    """Basic application for holding the viewing Frame"""
    def OnInit(self):
        """Initialise the application"""
        self.frame = frame = wx.Frame( None,
        )
        frame.CreateStatusBar()

        model = model = self.get_model( sys.argv[1])
        self.sq = SquareMap( frame, model=model)
        EVT_SQUARE_HIGHLIGHTED( self.sq, self.OnSquareSelected )
        frame.Show(True)
        self.SetTopWindow(frame)
        return True
    def get_model( self, path ):
        nodes = []
        for f in os.listdir( path ):
            full = os.path.join( path,f )
            if not os.path.islink( full ):
                if os.path.isfile( full ):
                    nodes.append( Node( full, os.stat( full ).st_size, () ) )
                elif os.path.isdir( full ):
                    nodes.append( self.get_model( full ))
        return Node( path, sum([x.size for x in nodes]), nodes )
    def OnSquareSelected( self, event ):
        text = self.sq.adapter.label( event.node )
        self.frame.SetToolTipString( text )

class Node( object ):
    """Really dumb file-system node object"""
    def __init__( self, path, size, children ):
        self.path = path
        self.size = size
        self.children = children
    def __repr__( self ):
        return '%s( %r, %r, %r )'%( self.__class__.__name__, self.path, self.size, self.children )


usage = 'squaremap.py somedirectory'

def main():
    """Mainloop for the application"""
    if not sys.argv[1:]:
        print(usage)
    else:
        app = TestApp(0)
        app.MainLoop()

if __name__ == "__main__":
    main()