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

# Copyright (c) 2012 - 2020 Detlev Offenbach <detlev@die-offenbachs.de>
#

"""
Module implementing the snapshot timer widget.
"""


from PyQt5.QtCore import pyqtSignal, Qt, QTimer, QRect
from PyQt5.QtGui import QPainter, QPalette
from PyQt5.QtWidgets import QWidget, QApplication, QToolTip

from Globals import qVersionTuple


class SnapshotTimer(QWidget):
    """
    Class implementing the snapshot timer widget.
    
    @signal timeout() emitted after the timer timed out
    """
    timeout = pyqtSignal()
    
    def __init__(self):
        """
        Constructor
        """
        super(SnapshotTimer, self).__init__(None)
        
        self.setWindowFlags(Qt.WindowStaysOnTopHint | Qt.FramelessWindowHint |
                            Qt.X11BypassWindowManagerHint)
        
        self.__timer = QTimer()
        self.__textRect = QRect()
        self.__time = 0
        self.__length = 0
        self.__toggle = True
        
        # text is taken from paintEvent with maximum number plus some margin
        try:
            fmWidth = self.fontMetrics().horizontalAdvance(self.tr(
                "Snapshot will be taken in %n seconds", "", 99))
        except AttributeError:
            fmWidth = self.fontMetrics().width(self.tr(
                "Snapshot will be taken in %n seconds", "", 99))
        self.resize(fmWidth + 6, self.fontMetrics().height() + 4)
        
        self.__timer.timeout.connect(self.__bell)
    
    def start(self, seconds):
        """
        Public method to start the timer.
        
        @param seconds timeout value (integer)
        """
        if qVersionTuple() >= (5, 10, 0):
            screenGeom = QApplication.screens()[0].geometry()
        else:
            screenGeom = QApplication.desktop().screenGeometry()
        self.move(screenGeom.width() // 2 - self.size().width() // 2,
                  screenGeom.top())
        self.__toggle = True
        self.__time = 0
        self.__length = seconds
        self.__timer.start(1000)
        self.show()
    
    def stop(self):
        """
        Public method to stop the timer.
        """
        self.setVisible(False)
        self.hide()
        self.__timer.stop()
    
    def __bell(self):
        """
        Private slot handling timer timeouts.
        """
        if self.__time == self.__length - 1:
            self.hide()
        else:
            if self.__time == self.__length:
                self.__timer.stop()
                self.timeout.emit()
        
        self.__time += 1
        self.__toggle = not self.__toggle
        self.update()
    
    def paintEvent(self, evt):
        """
        Protected method handling paint events.
        
        @param evt paint event (QPaintEvent)
        """
        painter = QPainter(self)
        
        if self.__time < self.__length:
            pal = QToolTip.palette()
            textBackgroundColor = pal.color(QPalette.Active, QPalette.Base)
            if self.__toggle:
                textColor = pal.color(QPalette.Active, QPalette.Text)
            else:
                textColor = pal.color(QPalette.Active, QPalette.Base)
            painter.setPen(textColor)
            painter.setBrush(textBackgroundColor)
            helpText = self.tr("Snapshot will be taken in %n seconds", "",
                               self.__length - self.__time)
            textRect = painter.boundingRect(
                self.rect().adjusted(2, 2, -2, -2),
                Qt.AlignHCenter | Qt.TextSingleLine, helpText)
            painter.drawText(textRect, Qt.AlignHCenter | Qt.TextSingleLine,
                             helpText)
    
    def enterEvent(self, evt):
        """
        Protected method handling the mouse cursor entering the widget.
        
        @param evt enter event (QEvent)
        """
        if qVersionTuple() >= (5, 10, 0):
            screenGeom = QApplication.screens()[0].geometry()
        else:
            screenGeom = QApplication.desktop().screenGeometry()
        if self.x() == screenGeom.left():
            self.move(
                screenGeom.x() +
                (screenGeom.width() // 2 - self.size().width() // 2),
                screenGeom.top())
        else:
            self.move(screenGeom.topLeft())
