Graphics/UMLClassDiagram.py

# -*- coding: utf-8 -*-

# Copyright (c) 2007 - 2010 Detlev Offenbach <detlev@die-offenbachs.de>
#

"""
Module implementing a dialog showing a UML like class diagram.
"""

import itertools

from PyQt4.QtCore import *
from PyQt4.QtGui import *

import Utilities.ModuleParser

from .UMLDialog import UMLDialog
from .ClassItem import ClassItem, ClassModel
from .AssociationItem import AssociationItem, Generalisation
from . import GraphicsUtilities

class UMLClassDiagram(UMLDialog):
    """
    Class implementing a dialog showing a UML like class diagram.
    """
    def __init__(self, file, parent = None, name = None, noAttrs = False):
        """
        Constructor
        
        @param file filename of a python module to be shown (string)
        @param parent parent widget of the view (QWidget)
        @param name name of the view widget (string)
        @keyparam noAttrs flag indicating, that no attributes should be shown (boolean)
        """
        self.file = file
        self.noAttrs = noAttrs
        
        UMLDialog.__init__(self, self.file, parent)
        
        if not name:
            self.setObjectName("UMLClassDiagram")
        else:
            self.setObjectName(name)
        
        self.allClasses = {}
        self.allModules = {}
        
        self.connect(self.umlView, SIGNAL("relayout()"), self.relayout)
        
    def __getCurrentShape(self, name):
        """
        Private method to get the named shape.
        
        @param name name of the shape (string)
        @return shape (QGraphicsItem)
        """
        return self.allClasses.get(name)
        
    def __buildClasses(self):
        """
        Private method to build the class shapes of the class diagram.
        
        The algorithm is borrowed from Boa Constructor.
        """
        try:
            module = Utilities.ModuleParser.readModule(self.file)
        except ImportError:
            ct = QGraphicsTextItem(None, self.scene)
            ct.setHtml(\
                self.trUtf8("The module <b>'{0}'</b> could not be found.")
                    .format(self.file))
            return
        
        if self.file not in self.allModules:
            self.allModules[self.file] = []
        
        routes = []
        nodes = []
        todo = [module.createHierarchy()]
        classesFound = False
        while todo:
            hierarchy = todo[0]
            for className in hierarchy:
                classesFound = True
                cw = self.__getCurrentShape(className)
                if not cw and className.find('.') >= 0:
                    cw = self.__getCurrentShape(className.split('.')[-1])
                    if cw:
                        self.allClasses[className] = cw
                        if className not in self.allModules[self.file]:
                            self.allModules[self.file].append(className)
                if cw and cw.noAttrs != self.noAttrs:
                    cw = None
                if cw and not (cw.external and \
                               (className in module.classes or
                                className in module.modules)
                              ):
                    if cw.scene() != self.scene:
                        self.scene.addItem(cw)
                        cw.setPos(10, 10)
                        if className not in nodes:
                            nodes.append(className)
                else:
                    if className in module.classes:
                        # this is a local class (defined in this module)
                        self.__addLocalClass(\
                            className, module.classes[className], 0, 0)
                    elif className in module.modules:
                        # this is a local module (defined in this module)
                        self.__addLocalClass(\
                            className, module.modules[className], 0, 0, True)
                    else:
                        self.__addExternalClass(className, 0, 0)
                    nodes.append(className)
                
                if hierarchy.get(className):
                    todo.append(hierarchy.get(className))
                    children = list(hierarchy.get(className).keys())
                    for child in children:
                        if (className, child) not in routes:
                            routes.append((className, child))
            
            del todo[0]
        
        if classesFound:
            self.__arrangeClasses(nodes, routes[:])
            self.__createAssociations(routes)
        else:
            ct = QGraphicsTextItem(None, self.scene)
            ct.setHtml(\
                self.trUtf8("The module <b>'{0}'</b> does not contain any classes.")\
                .format(self.file))
        
    def __arrangeClasses(self, nodes, routes, whiteSpaceFactor = 1.2):
        """
        Private method to arrange the shapes on the canvas.
        
        The algorithm is borrowed from Boa Constructor.
        """
        generations = GraphicsUtilities.sort(nodes, routes)
        
        # calculate width and height of all elements
        sizes = []
        for generation in generations:
            sizes.append([])
            for child in generation:
                sizes[-1].append(self.__getCurrentShape(child).sceneBoundingRect())
        
        # calculate total width and total height
        width = 0
        height = 0
        widths = []
        heights = []
        for generation in sizes:
            currentWidth = 0
            currentHeight = 0
            
            for rect in generation:
                if rect.bottom() > currentHeight:
                    currentHeight = rect.bottom()
                currentWidth = currentWidth + rect.right()
            
            # update totals
            if currentWidth > width:
                width = currentWidth
            height = height + currentHeight
            
            # store generation info
            widths.append(currentWidth)
            heights.append(currentHeight)
        
        # add in some whitespace
        width = width * whiteSpaceFactor
        rawHeight = height
        height = height * whiteSpaceFactor - 20
        verticalWhiteSpace = (height - rawHeight) / (len(generations) - 1.0 or 2.0)
        
        sceneRect = self.umlView.sceneRect()
        width += 50.0
        height += 50.0
        swidth = width < sceneRect.width() and sceneRect.width() or width
        sheight = height < sceneRect.height() and sceneRect.height() or height
        self.umlView.setSceneSize(swidth, sheight)
        
        # distribute each generation across the width and the
        # generations across height
        y = 10.0
        for currentWidth, currentHeight, generation in \
                itertools.zip_longest(widths, heights, generations):
            x = 10.0
            # whiteSpace is the space between any two elements
            whiteSpace = (width - currentWidth - 20) / (len(generation) - 1.0 or 2.0)
            for className in generation:
                cw = self.__getCurrentShape(className)
                cw.setPos(x, y)
                rect = cw.sceneBoundingRect()
                x = x + rect.width() + whiteSpace
            y = y + currentHeight + verticalWhiteSpace
        
    def __addLocalClass(self, className, _class, x, y, isRbModule = False):
        """
        Private method to add a class defined in the module.
        
        @param className name of the class to be as a dictionary key (string)
        @param _class class to be shown (ModuleParser.Class)
        @param x x-coordinate (float)
        @param y y-coordinate (float)
        @param isRbModule flag indicating a Ruby module (boolean)
        """
        meths = sorted(_class.methods.keys())
        attrs = sorted(_class.attributes.keys())
        name = _class.name
        if isRbModule:
            name = "%s (Module)" % name
        cl = ClassModel(name, meths[:], attrs[:])
        cw = ClassItem(cl, False, x, y, noAttrs = self.noAttrs, scene = self.scene)
        self.allClasses[className] = cw
        if _class.name not in self.allModules[self.file]:
            self.allModules[self.file].append(_class.name)
        
    def __addExternalClass(self, _class, x, y):
        """
        Private method to add a class defined outside the module.
        
        If the canvas is too small to take the shape, it
        is enlarged.
        
        @param _class class to be shown (string)
        @param x x-coordinate (float)
        @param y y-coordinate (float)
        """
        cl = ClassModel(_class)
        cw = ClassItem(cl, True, x, y, noAttrs = self.noAttrs, scene = self.scene)
        self.allClasses[_class] = cw
        if _class not in self.allModules[self.file]:
            self.allModules[self.file].append(_class)
        
    def __createAssociations(self, routes):
        """
        Private method to generate the associations between the class shapes.
        
        @param routes list of relationsships
        """
        for route in routes:
            if len(route) > 1:
                assoc = AssociationItem(\
                        self.__getCurrentShape(route[1]),
                        self.__getCurrentShape(route[0]),
                        Generalisation)
                self.scene.addItem(assoc)
        
    def show(self):
        """
        Overriden method to show the dialog.
        """
        self.__buildClasses()
        UMLDialog.show(self)
        
    def relayout(self):
        """
        Public method to relayout the diagram.
        """
        self.allClasses.clear()
        self.allModules.clear()
        self.__buildClasses()