Graphics/UMLGraphicsView.py

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

# Copyright (c) 2007 - 2011 Detlev Offenbach <detlev@die-offenbachs.de>
#

"""
Module implementing a subclass of E5GraphicsView for our diagrams.
"""

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

from E5Graphics.E5GraphicsView import E5GraphicsView

from E5Gui import E5MessageBox

from .UMLItem import UMLItem
from .UMLSceneSizeDialog import UMLSceneSizeDialog
from .ZoomDialog import ZoomDialog

import UI.Config
import UI.PixmapCache

import Preferences

class UMLGraphicsView(E5GraphicsView):
    """
    Class implementing a specialized E5GraphicsView for our diagrams.
    
    @signal relayout() emitted to indicate a relayout of the diagram
        is requested
    """
    relayout = pyqtSignal()
    
    def __init__(self, scene, diagramName = "Unnamed", parent = None, name = None):
        """
        Constructor
        
        @param scene reference to the scene object (QGraphicsScene)
        @param diagramName name of the diagram (string)
        @param parent parent widget of the view (QWidget)
        @param name name of the view widget (string)
        """
        E5GraphicsView.__init__(self, scene, parent)
        if name:
            self.setObjectName(name)
        
        self.diagramName = diagramName
        
        self.border = 10
        self.deltaSize = 100.0
        
        self.__initActions()
        
        scene.changed.connect(self.__sceneChanged)
        
    def __initActions(self):
        """
        Private method to initialize the view actions.
        """
        self.alignMapper = QSignalMapper(self)
        self.alignMapper.mapped[int].connect(self.__alignShapes)
        
        self.deleteShapeAct = \
            QAction(UI.PixmapCache.getIcon("deleteShape.png"),
                    self.trUtf8("Delete shapes"), self)
        self.deleteShapeAct.triggered[()].connect(self.__deleteShape)
        
        self.saveAct = \
            QAction(UI.PixmapCache.getIcon("fileSave.png"),
                    self.trUtf8("Save as PNG"), self)
        self.saveAct.triggered[()].connect(self.__saveImage)
        
        self.printAct = \
            QAction(UI.PixmapCache.getIcon("print.png"),
                    self.trUtf8("Print"), self)
        self.printAct.triggered[()].connect(self.__printDiagram)
        
        self.printPreviewAct = \
            QAction(UI.PixmapCache.getIcon("printPreview.png"),
                    self.trUtf8("Print Preview"), self)
        self.printPreviewAct.triggered[()].connect(self.__printPreviewDiagram)
        
        self.zoomInAct = \
            QAction(UI.PixmapCache.getIcon("zoomIn.png"),
                    self.trUtf8("Zoom in"), self)
        self.zoomInAct.triggered[()].connect(self.zoomIn)
        
        self.zoomOutAct = \
            QAction(UI.PixmapCache.getIcon("zoomOut.png"),
                    self.trUtf8("Zoom out"), self)
        self.zoomOutAct.triggered[()].connect(self.zoomOut)
        
        self.zoomAct = \
            QAction(UI.PixmapCache.getIcon("zoomTo.png"),
                    self.trUtf8("Zoom..."), self)
        self.zoomAct.triggered[()].connect(self.__zoom)
        
        self.zoomResetAct = \
            QAction(UI.PixmapCache.getIcon("zoomReset.png"),
                    self.trUtf8("Zoom reset"), self)
        self.zoomResetAct.triggered[()].connect(self.zoomReset)
        
        self.incWidthAct = \
            QAction(UI.PixmapCache.getIcon("sceneWidthInc.png"),
                    self.trUtf8("Increase width by {0} points").format(self.deltaSize), 
                    self)
        self.incWidthAct.triggered[()].connect(self.__incWidth)
        
        self.incHeightAct = \
            QAction(UI.PixmapCache.getIcon("sceneHeightInc.png"),
                    self.trUtf8("Increase height by {0} points").format(self.deltaSize), 
                    self)
        self.incHeightAct.triggered[()].connect(self.__incHeight)
        
        self.decWidthAct = \
            QAction(UI.PixmapCache.getIcon("sceneWidthDec.png"),
                    self.trUtf8("Decrease width by {0} points").format(self.deltaSize), 
                    self)
        self.decWidthAct.triggered[()].connect(self.__decWidth)
        
        self.decHeightAct = \
            QAction(UI.PixmapCache.getIcon("sceneHeightDec.png"),
                    self.trUtf8("Decrease height by {0} points").format(self.deltaSize), 
                    self)
        self.decHeightAct.triggered[()].connect(self.__decHeight)
        
        self.setSizeAct = \
            QAction(UI.PixmapCache.getIcon("sceneSize.png"),
                    self.trUtf8("Set size"), self)
        self.setSizeAct.triggered[()].connect(self.__setSize)
        
        self.relayoutAct = \
            QAction(UI.PixmapCache.getIcon("reload.png"),
                    self.trUtf8("Re-Layout"), self)
        self.relayoutAct.triggered[()].connect(self.__relayout)
        
        self.alignLeftAct = \
            QAction(UI.PixmapCache.getIcon("shapesAlignLeft.png"), 
                    self.trUtf8("Align Left"), self)
        self.alignMapper.setMapping(self.alignLeftAct, Qt.AlignLeft)
        self.alignLeftAct.triggered[()].connect(self.alignMapper.map)
        
        self.alignHCenterAct = \
            QAction(UI.PixmapCache.getIcon("shapesAlignHCenter.png"), 
                    self.trUtf8("Align Center Horizontal"), self)
        self.alignMapper.setMapping(self.alignHCenterAct, Qt.AlignHCenter)
        self.alignHCenterAct.triggered[()].connect(self.alignMapper.map)
        
        self.alignRightAct = \
            QAction(UI.PixmapCache.getIcon("shapesAlignRight.png"), 
                    self.trUtf8("Align Right"), self)
        self.alignMapper.setMapping(self.alignRightAct, Qt.AlignRight)
        self.alignRightAct.triggered[()].connect(self.alignMapper.map)
        
        self.alignTopAct = \
            QAction(UI.PixmapCache.getIcon("shapesAlignTop.png"), 
                    self.trUtf8("Align Top"), self)
        self.alignMapper.setMapping(self.alignTopAct, Qt.AlignTop)
        self.alignTopAct.triggered[()].connect(self.alignMapper.map)
        
        self.alignVCenterAct = \
            QAction(UI.PixmapCache.getIcon("shapesAlignVCenter.png"), 
                    self.trUtf8("Align Center Vertical"), self)
        self.alignMapper.setMapping(self.alignVCenterAct, Qt.AlignVCenter)
        self.alignVCenterAct.triggered[()].connect(self.alignMapper.map)
        
        self.alignBottomAct = \
            QAction(UI.PixmapCache.getIcon("shapesAlignBottom.png"), 
                    self.trUtf8("Align Bottom"), self)
        self.alignMapper.setMapping(self.alignBottomAct, Qt.AlignBottom)
        self.alignBottomAct.triggered[()].connect(self.alignMapper.map)
        
    def __checkSizeActions(self):
        """
        Private slot to set the enabled state of the size actions.
        """
        diagramSize = self._getDiagramSize(10)
        sceneRect = self.scene().sceneRect()
        if (sceneRect.width() - self.deltaSize) <= diagramSize.width():
            self.decWidthAct.setEnabled(False)
        else:
            self.decWidthAct.setEnabled(True)
        if (sceneRect.height() - self.deltaSize) <= diagramSize.height():
            self.decHeightAct.setEnabled(False)
        else:
            self.decHeightAct.setEnabled(True)
        
    def __sceneChanged(self, areas):
        """
        Private slot called when the scene changes.
        
        @param areas list of rectangles that contain changes (list of QRectF)
        """
        if len(self.scene().selectedItems()) > 0:
            self.deleteShapeAct.setEnabled(True)
        else:
            self.deleteShapeAct.setEnabled(False)
        
    def initToolBar(self):
        """
        Public method to populate a toolbar with our actions.
        
        @return the populated toolBar (QToolBar)
        """
        toolBar = QToolBar(self.trUtf8("Graphics"), self)
        toolBar.setIconSize(UI.Config.ToolBarIconSize)
        toolBar.addAction(self.deleteShapeAct)
        toolBar.addSeparator()
        toolBar.addAction(self.saveAct)
        toolBar.addSeparator()
        toolBar.addAction(self.printPreviewAct)
        toolBar.addAction(self.printAct)
        toolBar.addSeparator()
        toolBar.addAction(self.zoomInAct)
        toolBar.addAction(self.zoomOutAct)
        toolBar.addAction(self.zoomAct)
        toolBar.addAction(self.zoomResetAct)
        toolBar.addSeparator()
        toolBar.addAction(self.alignLeftAct)
        toolBar.addAction(self.alignHCenterAct)
        toolBar.addAction(self.alignRightAct)
        toolBar.addAction(self.alignTopAct)
        toolBar.addAction(self.alignVCenterAct)
        toolBar.addAction(self.alignBottomAct)
        toolBar.addSeparator()
        toolBar.addAction(self.incWidthAct)
        toolBar.addAction(self.incHeightAct)
        toolBar.addAction(self.decWidthAct)
        toolBar.addAction(self.decHeightAct)
        toolBar.addAction(self.setSizeAct)
        toolBar.addSeparator()
        toolBar.addAction(self.relayoutAct)
        
        return toolBar
        
    def filteredItems(self, items):
        """
        Public method to filter a list of items.
        
        @param items list of items as returned by the scene object
            (QGraphicsItem)
        @return list of interesting collision items (QGraphicsItem)
        """
        return [itm for itm in items if isinstance(itm, UMLItem)]
        
    def selectItems(self, items):
        """
        Public method to select the given items.
        
        @param items list of items to be selected (list of QGraphicsItemItem)
        """
        # step 1: deselect all items
        self.unselectItems()
        
        # step 2: select all given items
        for itm in items:
            if isinstance(itm, UMLWidget):
                itm.setSelected(True)
        
    def selectItem(self, item):
        """
        Public method to select an item.
        
        @param item item to be selected (QGraphicsItemItem)
        """
        if isinstance(item, UMLWidget):
            item.setSelected(not item.isSelected())
        
    def __deleteShape(self):
        """
        Private method to delete the selected shapes from the display.
        """
        for item in self.scene().selectedItems():
            item.removeAssociations()
            item.setSelected(False)
            self.scene().removeItem(item)
            del item
        
    def __incWidth(self):
        """
        Private method to handle the increase width context menu entry.
        """
        self.resizeScene(self.deltaSize, True)
        self.__checkSizeActions()
        
    def __incHeight(self):
        """
        Private method to handle the increase height context menu entry.
        """
        self.resizeScene(self.deltaSize, False)
        self.__checkSizeActions()
        
    def __decWidth(self):
        """
        Private method to handle the decrease width context menu entry.
        """
        self.resizeScene(-self.deltaSize, True)
        self.__checkSizeActions()
        
    def __decHeight(self):
        """
        Private method to handle the decrease height context menu entry.
        """
        self.resizeScene(-self.deltaSize, False)
        self.__checkSizeActions()
        
    def __setSize(self):
        """
        Private method to handle the set size context menu entry.
        """
        rect = self._getDiagramRect(10)
        sceneRect = self.scene().sceneRect()
        dlg = UMLSceneSizeDialog(sceneRect.width(), sceneRect.height(),
                                  rect.width(), rect.height(), self)
        if dlg.exec_() == QDialog.Accepted:
            width, height = dlg.getData()
            self.setSceneSize(width, height)
        self.__checkSizeActions()
        
    def __saveImage(self):
        """
        Private method to handle the save context menu entry.
        """
        fname, selectedFilter = QFileDialog.getSaveFileNameAndFilter(
            self,
            self.trUtf8("Save Diagram"),
            "",
            self.trUtf8("Portable Network Graphics (*.png);;"
                        "Scalable Vector Graphics (*.svg)"),
            "",
            QFileDialog.Options(QFileDialog.DontConfirmOverwrite |
                                QFileDialog.DontUseNativeDialog))
        if fname:
            ext = QFileInfo(fname).suffix()
            if not ext:
                ex = selectedFilter.split("(*")[1].split(")")[0]
                if ex:
                    fname += ex
            if QFileInfo(fname).exists():
                res = E5MessageBox.yesNo(self,
                    self.trUtf8("Save Diagram"),
                    self.trUtf8("<p>The file <b>{0}</b> already exists."
                                " Overwrite it?</p>").format(fname),
                    icon = E5MessageBox.Warning)
                if not res:
                    return
            
            success = self.saveImage(fname, QFileInfo(fname).suffix().upper())
            if not success:
                E5MessageBox.critical(self,
                    self.trUtf8("Save Diagram"),
                    self.trUtf8("""<p>The file <b>{0}</b> could not be saved.</p>""")
                        .format(fname))
        
    def __relayout(self):
        """
        Private method to handle the re-layout context menu entry.
        """
        scene = self.scene()
        for itm in list(scene.items())[:]:
            if itm.scene() == scene:
                scene.removeItem(itm)
        self.relayout.emit()
        
    def __printDiagram(self):
        """
        Private slot called to print the diagram.
        """
        printer = QPrinter(mode = QPrinter.ScreenResolution)
        printer.setFullPage(True)
        if Preferences.getPrinter("ColorMode"):
            printer.setColorMode(QPrinter.Color)
        else:
            printer.setColorMode(QPrinter.GrayScale)
        if Preferences.getPrinter("FirstPageFirst"):
            printer.setPageOrder(QPrinter.FirstPageFirst)
        else:
            printer.setPageOrder(QPrinter.LastPageFirst)
        printer.setPrinterName(Preferences.getPrinter("PrinterName"))
        
        printDialog = QPrintDialog(printer, self)
        if printDialog.exec_():
            self.printDiagram(printer, self.diagramName)
        
    def __printPreviewDiagram(self):
        """
        Private slot called to show a print preview of the diagram.
        """
        from PyQt4.QtGui import QPrintPreviewDialog
        
        printer = QPrinter(mode = QPrinter.ScreenResolution)
        printer.setFullPage(True)
        if Preferences.getPrinter("ColorMode"):
            printer.setColorMode(QPrinter.Color)
        else:
            printer.setColorMode(QPrinter.GrayScale)
        if Preferences.getPrinter("FirstPageFirst"):
            printer.setPageOrder(QPrinter.FirstPageFirst)
        else:
            printer.setPageOrder(QPrinter.LastPageFirst)
        printer.setPrinterName(Preferences.getPrinter("PrinterName"))
        
        preview = QPrintPreviewDialog(printer, self)
        preview.paintRequested[QPrinter].connect(self.printDiagram)
        preview.exec_()
        
    def __zoom(self):
        """
        Private method to handle the zoom context menu action.
        """
        dlg = ZoomDialog(self.zoom(), self)
        if dlg.exec_() == QDialog.Accepted:
            zoom = dlg.getZoomSize()
            self.setZoom(zoom)
        
    def setDiagramName(self, name):
        """
        Public slot to set the diagram name.
        
        @param name diagram name (string)
        """
        self.diagramName = name
        
    def __alignShapes(self, alignment):
        """
        Private slot to align the selected shapes.
        
        @param alignment alignment type (Qt.AlignmentFlag)
        """
        # step 1: get all selected items
        items = self.scene().selectedItems()
        if len(items) <= 1:
            return
        
        # step 2: find the index of the item to align in relation to
        amount = None
        for i, item in enumerate(items):
            rect = item.sceneBoundingRect()
            if alignment == Qt.AlignLeft:
                if amount is None or rect.x() < amount:
                    amount = rect.x()
                    index = i
            elif alignment == Qt.AlignRight:
                if amount is None or rect.x() + rect.width() > amount:
                    amount = rect.x() + rect.width()
                    index = i
            elif alignment == Qt.AlignHCenter:
                if amount is None or rect.width() > amount:
                    amount = rect.width()
                    index = i
            elif alignment == Qt.AlignTop:
                if amount is None or rect.y() < amount:
                    amount = rect.y()
                    index = i
            elif alignment == Qt.AlignBottom:
                if amount is None or rect.y() + rect.height() > amount:
                    amount = rect.y() + rect.height()
                    index = i
            elif alignment == Qt.AlignVCenter:
                if amount is None or rect.height() > amount:
                    amount = rect.height()
                    index = i
        rect = items[index].sceneBoundingRect()
        
        # step 3: move the other items
        for i, item in enumerate(items):
            if i == index:
                continue
            itemrect = item.sceneBoundingRect()
            xOffset = yOffset = 0
            if alignment == Qt.AlignLeft:
                xOffset = rect.x() - itemrect.x()
            elif alignment == Qt.AlignRight:
                xOffset = (rect.x() + rect.width()) - \
                          (itemrect.x() + itemrect.width())
            elif alignment == Qt.AlignHCenter:
                xOffset = (rect.x() + rect.width() // 2) - \
                          (itemrect.x() + itemrect.width() // 2)
            elif alignment == Qt.AlignTop:
                yOffset = rect.y() - itemrect.y()
            elif alignment == Qt.AlignBottom:
                yOffset = (rect.y() + rect.height()) - \
                          (itemrect.y() + itemrect.height())
            elif alignment == Qt.AlignVCenter:
                yOffset = (rect.y() + rect.height() // 2) - \
                          (itemrect.y() + itemrect.height() // 2)
            item.moveBy(xOffset, yOffset)
        
        self.scene().update()