#!/usr/bin/python

"""**************************************************************************
**
** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
** All rights reserved.
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the examples of the Qt Toolkit.
**
** You may use this file under the terms of the BSD license as follows:
**
** "Redistribution and use in source and binary forms, with or without
** modification, are permitted provided that the following conditions are
** met:
**   * Redistributions of source code must retain the above copyright
**     notice, this list of conditions and the following disclaimer.
**   * Redistributions in binary form must reproduce the above copyright
**     notice, this list of conditions and the following disclaimer in
**     the documentation and/or other materials provided with the
**     distribution.
**   * Neither the name of Nokia Corporation and its Subsidiary(-ies) nor
**     the names of its contributors may be used to endorse or promote
**     products derived from this software without specific prior written
**     permission.
**
** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
**
*****************************************************************************
** February 2011
** - stardelegate example ported to PySide by Arun Srinivasan 
**   <rulfzid@gmail.com>
**************************************************************************"""

from PySide.QtGui import (QWidget, QPainter)
from PySide.QtCore import Signal


class StarEditor(QWidget):
    """ The custome editor for editing StarRatings. """

    # A signal to tell the delegate when we've finished editing.
    editingFinished = Signal()

    def __init__(self, parent=None):
        """ Initialize the editor object, making sure we can watch mouse
            events.
        """
        super(StarEditor, self).__init__(parent)

        self.setMouseTracking(True)
        self.setAutoFillBackground(True)

    def sizeHint(self):
        """ Tell the caller how big we are. """
        return self.starRating.sizeHint()

    def paintEvent(self, event):
        """ Paint the editor, offloading the work to the StarRating class. """
        painter = QPainter(self)
        self.starRating.paint(painter, self.rect(), self.palette(), isEditable=True)
        
    def mouseMoveEvent(self, event):
        """ As the mouse moves inside the editor, track the position and 
            update the editor to display as many stars as necessary. 
        """
        star = self.starAtPosition(event.x())
        
        if (star != self.starRating.starCount) and (star != -1):
            self.starRating.starCount = star
            self.update()

    def mouseReleaseEvent(self, event):
        """ Once the user has clicked his/her chosen star rating, tell the
            delegate we're done editing.
        """
        self.editingFinished.emit()

    def starAtPosition(self, x):
        """ Calculate which star the user's mouse cursor is currently 
            hovering over.
        """
        star = (x / (self.starRating.sizeHint().width() /
                     self.starRating.maxStarCount)) + 1
        if (star <= 0) or (star > self.starRating.maxStarCount):
            return -1

        return star