ConnectableWidget.py

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import logging

from PyQt4.QtCore import QCoreApplication, QRect, QSize, QPoint, Qt
from PyQt4.QtGui import QMouseEvent, QPen, QColor

from Vispa.Gui.VispaWidget import VispaWidget
from Vispa.Gui.PortWidget import PortWidget,SinkPort,SourcePort
from Vispa.Gui.VispaWidgetOwner import VispaWidgetOwner
from Vispa.Gui.MenuWidget import MenuWidget

class ConnectableWidget(VispaWidget, VispaWidgetOwner):
    """ Widget which can be connection by PortConnections to other selectable widgets.
    
    Supports showing source and sink ports.
    The widget is owner of PortWidgets.
    """
    
    BACKGROUND_SHAPE = 'ROUNDRECT'
    SHOW_PORT_NAMES = False
    SHOW_PORT_LINES = False
    
    # possible positions for port names
    PORT_NAMES_NEXT_TO_PORTS = 0
    PORT_NAMES_ABOVE_PORTS = 1
    
    # default position for port names
    PORT_NAMES_POSITION = PORT_NAMES_NEXT_TO_PORTS
    
    NO_VALID_PORT_NAMES_POSITION_MESSAGE = "No valid position for port names was set."
    
    PORT_LINES_TARGET_X = -1     # See setShowPortNames()
    PORT_LINES_TARGET_Y = -1
   
    def __init__(self, parent=None, name=None):
        """ Constructor.
        """
        self._ports = []
        self._showPortNames = False
        self._portNamesPosition = None
        self._showPortLines = False
        self._menuWidget = None
        VispaWidget.__init__(self, parent)
        self.setShowPortNames(self.SHOW_PORT_NAMES)
        self.setPortNamesPosition(self.PORT_NAMES_POSITION)
        self.setShowPortLines(self.SHOW_PORT_LINES)
        
        if name:
            self.setTitle(name)
    
    def setShowPortNames(self, show):
        """ If True the port name's will be drawn.
        
        The port names wont be on the port itself.
        Instead they will appear next to the port icons on the ConnectableWidget.
        """
        self._showPortNames = show
        
    def setPortNamesPosition(self, position):
        """ Sets position where port names will be shown.
        
        Possible values are self.PORT_NAMES_NEXT_TO_PORTS and self.PORT_NAMES_ABOVE_PORTS.
        """
        self._portNamesPosition = position
    
    def setShowPortLines(self, show):
        """ If True lines from all ports to a specific target point are drawn.
        
        The target point is defined by PORT_LINES_TARGET_X and PORT_LINES_TARGET_Y.
        If both of these values are -1 the target point is set to the widget's centre.
        """
        self._showPortLines = show
        
    def getPortsHeight(self, portType):
        """ Returns height of all ports of given type.
        
        portType can either be 'sink" or 'source'.
        """
        if portType == "sink":
            ports = self.sinkPorts()
        elif portType == "source":
            ports = self.sourcePorts()
        else:
            return 0

        if len(ports) > 1:
            return ports[0].y() - ports[len(ports) -1].y() + 0.5 * self.getEffectivePortHeight(ports[len(ports) -1])
        elif len(ports) == 1:
            return self.getEffectivePortHeight(ports[0])
        else:
            return 0

    def sizeHint(self):
        """ Returns size needed to draw widget's content.
        """
        #logging.debug(self.__class__.__name__ + ": sizeHint()")
        # arrangePorts() needed because it will be called in rearnangeContent() after sizeHint()
        self.arrangePorts()
        
        neededWidth = self.getDistance('leftMargin', 1) + self.getDistance('rightMargin', 1)
        neededHeight = self.getDistance('topMargin', 1) + self.getDistance('bottomMargin', 1)
        imageSizeF = self.imageSizeF()
        
        # width
        titleWidth = 0
        if self.titleIsSet():
            titleWidth = self.getDistance('titleFieldWidth', 1)
            
        bodyWidth = 0
        sinkPortsWidth = 0
        sourcePortsWidth = 0
        if len(self.sinkPorts()) > 0:
            sinkPortsWidth = self.getDistance('leftMargin', 1) + PortWidget.WIDTH
        if len(self.sourcePorts()) > 0:
            sourcePortsWidth = self.getDistance('rightMargin', 1) + PortWidget.WIDTH
            
        if self._showPortNames:
            maxSinkTitleWidth = self._getMaxSinkTitleWidth()
            maxSourceTitleWidth = self._getMaxSourceTitleWidth()
            if self._portNamesPosition == self.PORT_NAMES_NEXT_TO_PORTS:
                bodyWidth += maxSinkTitleWidth + self.getDistance('rightMargin', 1) + maxSourceTitleWidth
            elif self._portNamesPosition == self.PORT_NAMES_ABOVE_PORTS:
                if maxSinkTitleWidth > PortWidget.WIDTH:
                    sinkPortsWidth = 0#self.getDistance('leftMargin', 1)
                if maxSourceTitleWidth > PortWidget.WIDTH:
                    sourcePortsWidth = 0#self.getDistance('rightMargin', 1)
                #bodyWidth += maxSinkTitleWidth + self.getDistance('rightMargin', 1) + maxSourceTitleWidth
                bodyWidth += maxSinkTitleWidth + maxSourceTitleWidth
            else:
                logging.waring(self.__class__.__name__ +": sizeHint() - "+ self.NO_VALID_PORT_NAMES_POSITION_MESSAGE)
        bodyWidth += sinkPortsWidth + sourcePortsWidth
                            
        if self.textFieldIsSet():
            bodyWidth += self.getDistance('textFieldWidth', 1)
        bodyWidth = max(imageSizeF.width() + self.getDistance("leftMargin", 1) + self.getDistance("rightMargin", 1), bodyWidth)
            
        neededWidth += max(titleWidth, bodyWidth)
        
        # height        
        if self.titleIsSet():
            neededHeight += self.getDistance('titleFieldHeight', 1)

        sinkPortsHeight = self.getPortsHeight("sink") / self.scale()
        sourcePortsHeight = self.getPortsHeight("source") / self.scale()
        textFieldHeight = 0
        if self.textFieldIsSet():
            textFieldHeight += self.textField().getHeight()
        neededHeight += max(sinkPortsHeight, sourcePortsHeight, textFieldHeight, imageSizeF.height())
        if bodyWidth != 0:
             neededHeight += self.getDistance('bottomMargin', 1)    # gap between header and body
             if self._showPortNames and (len(self.sinkPorts()) > 1 or len(self.sourcePorts()) > 1):
                 neededHeight += self.getDistance('bottomMargin', 1)    # additional gap for port names
        
        return QSize(neededWidth, neededHeight)
    
    def defineDistances(self, keepDefaultRatio=False):
        """ Extends distances of VispaWidget by the additionally needed distances for displaying ports.
        """
        #if scale == None:
        #    scale = self.scale()
        scale = 1.0
        
        if not VispaWidget.defineDistances(self, keepDefaultRatio):
            return False
        if len(self.sinkPorts()) > 0:
            self.distances()['textFieldX'] += PortWidget.WIDTH * scale + self.distances()['leftMargin']
            self.distances()['textFieldRight'] = self.distances()['textFieldX'] + self.distances()['textFieldWidth']
            if self._showPortNames:
                self.distances()['textFieldX'] += self._getMaxSinkTitleWidth() + self.distances()['leftMargin']
                self.distances()['textFieldRight'] += self._getMaxSinkTitleWidth() + self.distances()['leftMargin']
                
        firstPortY = self.distances()['height'] - self.distances()['bottomMargin'] - PortWidget.HEIGHT * scale
        self.distances()['firstSinkX'] = self.distances()['leftMargin']
        self.distances()['firstSinkY'] = firstPortY
        
        if self.textFieldIsSet():
            self.distances()['firstSourceX'] = self.distances()['textFieldRight'] + self.distances()['leftMargin']
        #else:
        self.distances()['firstSourceX'] = self.distances()['width'] - self.distances()['leftMargin'] - PortWidget.WIDTH * scale
        self.distances()['firstSourceY'] = firstPortY
        
        return True
        
#    def scaleChanged(self):
#        """ Arranges ports when scale has changed.
#        """
#        VispaWidget.scaleChanged(self)
#        self.arrangePorts()

    def setZoom(self, zoom):
        """ Arranges ports when zoom has changed.
        """
        VispaWidget.setZoom(self, zoom)
        #self.arrangePorts()
        
    def mousePressEvent(self, event):
        """ Makes sure event is forwarded to both base classes.
        
        If position of event is within the dropArea of a port a QMouseEvent is sent to the port. See dropArea().
        """
        dropAreaPort = self.dropAreaPort(event.pos())
        if dropAreaPort and dropAreaPort.isDragable():
            dropAreaPort.grabMouse()
            newEvent = QMouseEvent(event.type(), dropAreaPort.mapFromParent(event.pos()), event.button(), event.buttons(), event.modifiers())
            QCoreApplication.instance().sendEvent(dropAreaPort, newEvent)
        else:
            VispaWidgetOwner.mousePressEvent(self, event)
            VispaWidget.mousePressEvent(self, event)

    def mouseReleaseEvent(self, event):
        """ Calls realeseMouse() to make sure the widget does not grab the mouse.
        
        Necessary because ConnectableWidgetOwner.propagateEventUnderConnectionWidget() may call grabMouse() on this widget.
        """
        #logging.debug(self.__class__.__name__ +": mouseReleaseEvent()")
        self.releaseMouse()
        VispaWidget.mouseReleaseEvent(self, event)

    def ports(self):
        """ Returns list containing all source and sink port widgets.
        """
        return self._ports
    
    def addSinkPort(self, name, description=None):
        """ Adds sink port with name and optional description text.
        """
        port=SinkPort(self, name)
        self._addPort(port, description)
        return port
        
    def addSourcePort(self, name, description=None):
        """ Adds source port with name and optional description text.
        """
        port=SourcePort(self, name)
        self._addPort(port, description)
        return port
        
    def _addPort(self, port, description=None):
        self._ports.append(port)
        port.show()
        if description:
            self._ports[len(self._ports) - 1].setDescription(description)
        self.scheduleRearangeContent()
        
    def deleteLater(self):
        if self._menuWidget:
            self.removeMenu()
        for port in self._ports:
            port.deleteAttachedConnections()
        VispaWidget.deleteLater(self)
        
    def removePort(self, port):
        """ Removes given port if it is port of this widget.
        """
        if port in self._ports:
            port.deleteAttachedConnections()
            self._ports.remove(port)
            port.setParent(None)
            port.deleteLater()
            self.scheduleRearangeContent()
            
    def portExists(self, name, description=None):
        for port in self._ports:
            if port.name() == name and port.description() == description:
                return True
        return False

    def removePorts(self, filter=None):
        """ Remove registered ports.
        
        If filter is "sink" only sinks are removed, if it is "source" only sources are removed, otherwise all ports are removed.
        """
        if filter and (filter != "sink" and filter != "source"):
            filter = None
        
        parentIsWidgetOwner = False
        ports = self._ports[:]
        for port in ports:
            if not filter or port.portType() == filter:
                port.deleteAttachedConnections()
                self._ports.remove(port)
                port.setParent(None)
                port.deleteLater()
        self.scheduleRearangeContent()
        self.update()                    
        
    def sinkPorts(self):
        """ Returns list of all sink ports set.
        """
        return [port for port in self._ports if port.portType() == "sink"]
        def isSink(port):
            return port.portType() == 'sink'
        return filter(isSink, self._ports)
    
    def sourcePorts(self):
        """ Returns list of all source ports set.
        """
        return [port for port in self._ports if port.portType() == "source"]
        def isSource(port):
            return port.portType() == 'source'
        return filter(isSource, self._ports)
    
    def sinkPort(self, name):
        """ Returns sink port with given name or None if no such port is found.
        """
        return self.port(name, 'sink')
    
    def sourcePort(self, name):
        """ Returns source port with given name or None if no such port is found.
        """
        return self.port(name, 'source')
        
    def port(self, name, type):
        """ Returns port with given name and of given type.
        """
        if name == None:
            return None
        for port in self._ports:
            if port.portType() == type and port.name() == name:
                return port
        return None
    
    def _getMaxPortTitleWidth(self, type):
        if type == 'sink':
            ports = self.sinkPorts()
        elif type == 'source':
            ports = self.sourcePorts()
        else:
            return 0
        
        if len(ports) < 1:
            return 0
        return max([port.titleField().getWidth() for port in ports])
    
    def _getMaxSinkTitleWidth(self):
        return self._getMaxPortTitleWidth('sink')
    
    def _getMaxSourceTitleWidth(self):
        return self._getMaxPortTitleWidth('source')
    
    def getEffectivePortHeight(self, port):
        """ Returns the bigger value of the source height and the height of the port name text field.
        """ 
        portHeight = port.height()
        if not self._showPortNames:
            return portHeight
        
        titleHeight = port.titleField().getHeight() * self.scale()
        
        if self._portNamesPosition == self.PORT_NAMES_NEXT_TO_PORTS:
            return max(portHeight, titleHeight)
        elif self._portNamesPosition == self.PORT_NAMES_ABOVE_PORTS:
            return portHeight + titleHeight
        logging.waring(self.__class__.__name__ +": getEffectivePortHeight() - "+ self.NO_VALID_PORT_NAMES_POSITION_MESSAGE)
        return 0

    def rearangeContent(self):
        """ Arranges ports after content is rearranged by VispaWidget.
        """
        VispaWidget.rearangeContent(self)
        self.arrangePorts()     # has to be after rearangeContent(), prevents infinite loop (..getDistance())

    def centerSinglePortVertically(self, ports, portX):
        """ Centers port vertically within body part (widget without title) of ModuleWidget.
        
        ports can either be the list of source or sink ports of ModuleWidget.
        portX specifies the designated x coordinate to be adjustable for sinks and sources.
        """
        if len(ports) != 1 or not isinstance(ports[0], PortWidget):
            logging.warning(self.__class__.__name__ + ": centerSinglePortVertically() - This method was designed for plugins with one port. Falling back to default arrangement.")
            return False
        ports[0].move(portX, (self.height() + self.getDistance("titleFieldHeight")) * 0.5)
        return True
    
    def arrangePorts(self, filter=None):
        """ Sets positions of set ports depending on zoom factor.
        
        If filter is set it may be 'sink' or 'source'.
        """
        if filter and (filter != "sink" and filter != "source"):
            filter = None
        sinkCounter = 0
        sourceCounter = 0
        
        sinkX = self.getDistance('firstSinkX')
        sinkY = self.getDistance('firstSinkY')
        sourceX = self.getDistance('firstSourceX')
        sourceY = self.getDistance('firstSourceY')
        
        for port in self._ports:
            if port.portType() == 'sink' and (not filter or filter == "sink"):
                sinkCounter += 1
                port.move(sinkX, sinkY)
                sinkY -= self.getDistance('topMargin') + self.getEffectivePortHeight(port)  #+ PortWidget.HEIGHT * self.scale()
                
            elif port.portType() == 'source' and (not filter or filter == "source"):
                sourceCounter += 1
                port.move(sourceX, sourceY)
                sourceY -= self.getDistance('topMargin') + self.getEffectivePortHeight(port) # + PortWidget.HEIGHT * self.scale()

    def drawBody(self, painter):
        """ Takes care of painting widget content on given painter.
        """
        self.drawPortLines(painter)
        self.drawTextField(painter)
        self.drawImage(painter)
        self.drawPortNames(painter)
    
    def drawPortNames(self, painter):
        """ Paints port names next to PortWidget.
        
        See setShowPortNames().
        """
        if not self._showPortNames:
            return
        
        # factor should be 0.5, but text height is calculated to big
        titleHeightFactor = 0.4
        
        if self._portNamesPosition == self.PORT_NAMES_NEXT_TO_PORTS:
            for port in self.sinkPorts():
                if port.titleField():
                    port.titleField().paint(painter, port.x() + self.getDistance('rightMargin') + port.width(), port.y() - titleHeightFactor * port.getDistance('titleFieldHeight'), self.scale())
                
            for port in self.sourcePorts():
                if port.titleField():
                    #logging.debug(self.__class__.__name__ +": drawPortNames() - "+ port.name() +", "+ str(port.titleField()._autoscaleFlag))
                    port.titleField().paint(painter, port.x() - port.getDistance('titleFieldWidth') - self.getDistance('rightMargin'), port.y() - titleHeightFactor * port.getDistance('titleFieldHeight'), self.scale())
        elif self._portNamesPosition == self.PORT_NAMES_ABOVE_PORTS:
            painter.pen().setWidth(2)
            for port in self.sinkPorts():
                if port.titleField():
                    port.titleField().paint(painter, self.getDistance('firstSinkX'), port.y() - titleHeightFactor * port.getDistance('titleFieldHeight') - port.height(), self.scale())
                
            for port in self.sourcePorts():
                if port.titleField():
                    #logging.debug(self.__class__.__name__ +": drawPortNames() - "+ port.name() +", "+ str(port.titleField()._autoscaleFlag))
                    port.titleField().paint(painter, self.width() - port.getDistance('titleFieldWidth')- port.width()*0.5, port.y() - titleHeightFactor * port.getDistance('titleFieldHeight') - port.height(), self.scale())
        else:
            logging.waring(self.__class__.__name__ +": drawPortNames() - "+ self.NO_VALID_PORT_NAMES_POSITION_MESSAGE)

    def drawPortLines(self, painter):
        """ Draws lines from every port to a common point.
        
        See setShowPortLines().
        """
        if not self._showPortLines:
            return
        
        if self.PORT_LINES_TARGET_X == -1 and self.PORT_LINES_TARGET_Y == -1:
            targetPoint = QPoint(self.width(), self.height() + self.getDistance("titleFieldBottom")) * 0.5
        else:
            targetPoint = QPoint(self.PORT_LINES_TARGET_X, self.PORT_LINES_TARGET_Y) * self.scale()
        
        painter.setPen(QPen(QColor('black')))
        painter.pen().setWidth(1)
        
        for port in self.ports():
            painter.drawLine(port.connectionPoint("widget"), targetPoint)
    
    def dropArea(self, port):
        """ A drop area is a QRect in which the ConnectableWidget accepts dropping of PortWidgets to create connections.
        
        The area is greater than the port itself to make dropping easier.
        """
        if self._showPortNames:
            return port.frameGeometry().united(port.titleField().getDrawRect())
        topMargin = self.getDistance("topMargin")
        topMarginHalf = 0.5 * topMargin
        frameGeometry = port.frameGeometry()
        return QRect(frameGeometry.x() - topMarginHalf,
                     frameGeometry.y() - topMarginHalf,
                     frameGeometry.width() + topMargin,
                     frameGeometry.height() + topMargin)
            
    def dropAreaPort(self, position):
        """ If a port's drop area is associated with position the port is returned.
        
        If there is no drop area associated with the position None is returned.
        See dropArea().
        """
        for port in self._ports:
            if self.dropArea(port).contains(position):
                return port
        return None

    def mouseMoveEvent(self, event):
        if bool(event.buttons() & Qt.LeftButton):
            VispaWidget.mouseMoveEvent(self, event)
        elif self._menuWidget:
            self.positionizeMenuWidget()
        
        self.showMenu()
            
    def showMenu(self):            
        if self._menuWidget:
            self._menuWidget.show()
            self._menuWidget.raise_()
            
    def leaveEvent(self, event):
        #logging.debug("%s: leaveEvent()" % self.__class__.__name__)
        parentCursorPos = self.parent().mapFromGlobal(self.cursor().pos())
        bottomRight = self.geometry().bottomRight()
        if ( (not self.isSelected() or (self._menuWidget and self._menuWidget.cursorHasEntered())) \
         and (self._menuWidget and self.parent().childAt(parentCursorPos) != self._menuWidget) ) \
         or (self._menuWidget and ( parentCursorPos.x() > bottomRight.x() or parentCursorPos.y() > bottomRight.y())):
            self._menuWidget.hide()
    
    def menu(self):
        return self._menuWidget    
    
    def addMenuEntry(self, name, slot=None):
        if not self._menuWidget:
            self._menuWidget = MenuWidget(self.parent(), self)
            self.setMouseTracking(True)
        return self._menuWidget.addEntry(name, slot)

    def removeMenuEntry(self, entry):
        if not self._menuWidget:
            return
        self._menuWidget.removeEntry(entry)
        if self._menuWidget.len() == 0:
            self.removeMenu()
    
    def removeMenu(self):
        self._menuWidget.hide()
        self._menuWidget.setParent(None)
        self._menuWidget.deleteLater()
        self._menuWidget = None
        
    def positionizeMenuWidget(self):
        if self._menuWidget:
            headerOffset = 0
            if isinstance(self.parent(), VispaWidget):
                headerOffset = self.parent().getDistance("titleFieldBottom")
            self._menuWidget.move(max(0, self.x() - 0.5* (self._menuWidget.width() - self.width())), 
                                  max(0, headerOffset, self.y() - self._menuWidget.height() +1))
        
    def dragWidget(self, pPos):
        VispaWidget.dragWidget(self, pPos)
        self.positionizeMenuWidget()
        
    def select(self, sel=True, multiSelect=False):
        VispaWidget.select(self, sel, multiSelect)
        if not sel and self._menuWidget:
            self._menuWidget.hide()
    
    def move(self, *target):
        VispaWidget.move(self, *target)
        if self._menuWidget:
            self._menuWidget.hide()
        self.updateAttachedConnections()
            
    def updateAttachedConnections(self):
        for port in self._ports:
            port.updateAttachedConnections()
            
    def attachedConnections(self):
        connections = []
        for port in self._ports:
            connections += port.attachedConnections()
        return connections