Graphics/UMLClassDiagramBuilder.py

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

# Copyright (c) 2007 - 2013 Detlev Offenbach <detlev@die-offenbachs.de>
#

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

import itertools

from PyQt4.QtGui import QGraphicsTextItem

import Utilities
import Utilities.ModuleParser
import Preferences

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


class UMLClassDiagramBuilder(UMLDiagramBuilder):
    """
    Class implementing a builder for UML like class diagrams.
    """
    def __init__(self, dialog, view, project, file, noAttrs=False):
        """
        Constructor
        
        @param dialog reference to the UML dialog (UMLDialog)
        @param view reference to the view object (UMLGraphicsView)
        @param project reference to the project object (Project)
        @param file file name of a python module to be shown (string)
        @keyparam noAttrs flag indicating, that no attributes should be shown (boolean)
        """
        super().__init__(dialog, view, project)
        self.setObjectName("UMLClassDiagramBuilder")
        
        self.file = file
        self.noAttrs = noAttrs
    
    def initialize(self):
        """
        Public method to initialize the object.
        """
        pname = self.project.getProjectName()
        if pname and self.project.isProjectSource(self.file):
            name = self.trUtf8("Class Diagram {0}: {1}").format(
                pname, self.project.getRelativePath(self.file))
        else:
            name = self.trUtf8("Class Diagram: {0}").format(self.file)
        self.umlView.setDiagramName(name)
        
    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 buildDiagram(self):
        """
        Public method to build the class shapes of the class diagram.
        
        The algorithm is borrowed from Boa Constructor.
        """
        self.allClasses = {}
        self.allModules = {}
        
        try:
            extensions = Preferences.getPython("PythonExtensions") + \
                Preferences.getPython("Python3Extensions") + ['.rb']
            module = Utilities.ModuleParser.readModule(self.file, extensions=extensions,
                                                       caching=False)
        except ImportError:
            ct = QGraphicsTextItem(None)
            ct.setHtml(
                self.trUtf8("The module <b>'{0}'</b> could not be found.")
                    .format(self.file))
            self.scene.addItem(ct)
            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)
            self.umlView.autoAdjustSceneSize(limit=True)
        else:
            ct = QGraphicsTextItem(None)
            ct.setHtml(
                self.trUtf8("The module <b>'{0}'</b> does not contain any classes.")\
                .format(self.file))
            self.scene.addItem(ct)
        
    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 = max(
##            (height - rawHeight) / (len(generations) - 1.0 or 2.0),
##            40.0
##        )
        verticalWhiteSpace = 40.0
        
        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 = "{0} (Module)".format(name)
        cl = ClassModel(name, meths[:], attrs[:])
        cw = ClassItem(cl, False, x, y, noAttrs=self.noAttrs, scene=self.scene)
        cw.setId(self.umlView.getItemId())
        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)
        cw.setId(self.umlView.getItemId())
        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,
                        topToBottom=True)
                self.scene.addItem(assoc)
    
    def getPersistenceData(self):
        """
        Public method to get a string for data to be persisted.
        
        @return persisted data string (string)
        """
        return "file={0}, no_attributes={1}".format(self.file, self.noAttrs)
    
    def parsePersistenceData(self, version, data):
        """
        Public method to parse persisted data.
        
        @param version version of the data (string)
        @param data persisted data to be parsed (string)
        @return flag indicating success (boolean)
        """
        parts = data.split(", ")
        if len(parts) != 2 or \
           not parts[0].startswith("file=") or \
           not parts[1].startswith("no_attributes="):
            return False
        
        self.file = parts[0].split("=", 1)[1].strip()
        self.noAttrs = Utilities.toBool(parts[1].split("=", 1)[1].strip())
        
        self.initialize()
        
        return True