#!/usr/bin/python

#############################################################################
##
## Copyright (C) 2010 Hans-Peter Jansen <hpj@urpla.net>
## Copyright (C) 2011 Arun Srinivasan <rulfzid@gmail.com>
## Copyright (C) 2016 The Qt Company Ltd.
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from PySide2.QtWidgets import (QWidget)
from PySide2.QtGui import (QPainter)
from PySide2.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