# Copyright (C) 2013 Riverbank Computing Limited.
# Copyright (C) 2022 The Qt Company Ltd.
# SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause

import sys
import math

from PySide6.QtCore import (QEasingCurve, QLineF, QMimeData, QPoint, QPointF,
                            QRandomGenerator, QRectF, QTimeLine, Qt)
from PySide6.QtGui import (QBrush, QColor, QDrag, QImage, QPainter, QPixmap,
                           QPen, QTransform)
from PySide6.QtWidgets import (QApplication, QGraphicsItem,
                               QGraphicsItemAnimation, QGraphicsScene,
                               QGraphicsView)

import dragdroprobot_rc


def random(boundary):
    return QRandomGenerator.global_().bounded(boundary)


class ColorItem(QGraphicsItem):
    n = 0

    def __init__(self):
        super().__init__()

        self.color = QColor(random(256), random(256), random(256))

        (r, g, b) = (self.color.red(), self.color.green(), self.color.blue())
        self.setToolTip(
            f"QColor({r}, {g}, {b})\nClick and drag this color onto the robot!")
        self.setCursor(Qt.OpenHandCursor)
        self._start_drag_distance = QApplication.startDragDistance()

    def boundingRect(self):
        return QRectF(-15.5, -15.5, 34, 34)

    def paint(self, painter, option, widget):
        painter.setPen(Qt.NoPen)
        painter.setBrush(Qt.darkGray)
        painter.drawEllipse(-12, -12, 30, 30)
        painter.setPen(QPen(Qt.black, 1))
        painter.setBrush(QBrush(self.color))
        painter.drawEllipse(-15, -15, 30, 30)

    def mousePressEvent(self, event):
        if event.button() != Qt.LeftButton:
            event.ignore()
            return

        self.setCursor(Qt.ClosedHandCursor)

    def mouseMoveEvent(self, event):
        start = QPointF(event.buttonDownScreenPos(Qt.LeftButton))
        if QLineF(event.screenPos(), start).length() < self._start_drag_distance:
            return

        drag = QDrag(event.widget())
        mime = QMimeData()
        drag.setMimeData(mime)

        ColorItem.n += 1
        if ColorItem.n > 2 and random(3) == 0:
            image = QImage(':/images/head.png')
            mime.setImageData(image)
            drag.setPixmap(QPixmap.fromImage(image).scaled(30, 40))
            drag.setHotSpot(QPoint(15, 30))
        else:
            mime.setColorData(self.color)
            (r, g, b) = (self.color.red(), self.color.green(), self.color.blue())
            mime.setText(f"#{r:02x}{g:02x}{b:02x}")

            pixmap = QPixmap(34, 34)
            pixmap.fill(Qt.white)

            with QPainter(pixmap) as painter:
                painter.translate(15, 15)
                painter.setRenderHint(QPainter.Antialiasing)
                self.paint(painter, None, None)

            pixmap.setMask(pixmap.createHeuristicMask())

            drag.setPixmap(pixmap)
            drag.setHotSpot(QPoint(15, 20))

        drag.exec()
        self.setCursor(Qt.OpenHandCursor)

    def mouseReleaseEvent(self, event):
        self.setCursor(Qt.OpenHandCursor)


class RobotPart(QGraphicsItem):
    def __init__(self, parent=None):
        super().__init__(parent)

        self.color = QColor(Qt.lightGray)
        self.pixmap = None
        self._drag_over = False

        self.setAcceptDrops(True)

    def dragEnterEvent(self, event):
        if (event.mimeData().hasColor() or
                (isinstance(self, RobotHead) and event.mimeData().hasImage())):
            event.setAccepted(True)
            self._drag_over = True
            self.update()
        else:
            event.setAccepted(False)

    def dragLeaveEvent(self, event):
        self._drag_over = False
        self.update()

    def dropEvent(self, event):
        self._drag_over = False
        if event.mimeData().hasColor():
            self.color = QColor(event.mimeData().colorData())
        elif event.mimeData().hasImage():
            self.pixmap = QPixmap(event.mimeData().imageData())

        self.update()


class RobotHead(RobotPart):
    def boundingRect(self):
        return QRectF(-15, -50, 30, 50)

    def paint(self, painter, option, widget=None):
        if not self.pixmap:
            painter.setBrush(self._drag_over and self.color.lighter(130)
                                            or self.color)
            painter.drawRoundedRect(-10, -30, 20, 30, 25, 25, Qt.RelativeSize)
            painter.setBrush(Qt.white)
            painter.drawEllipse(-7, -3 - 20, 7, 7)
            painter.drawEllipse(0, -3 - 20, 7, 7)
            painter.setBrush(Qt.black)
            painter.drawEllipse(-5, -1 - 20, 2, 2)
            painter.drawEllipse(2, -1 - 20, 2, 2)
            painter.setPen(QPen(Qt.black, 2))
            painter.setBrush(Qt.NoBrush)
            painter.drawArc(-6, -2 - 20, 12, 15, 190 * 16, 160 * 16)
        else:
            painter.scale(.2272, .2824)
            painter.drawPixmap(QPointF(-15 * 4.4, -50 * 3.54), self.pixmap)


class RobotTorso(RobotPart):
    def boundingRect(self):
        return QRectF(-30, -20, 60, 60)

    def paint(self, painter, option, widget=None):
        painter.setBrush(self._drag_over and self.color.lighter(130)
                                        or self.color)
        painter.drawRoundedRect(-20, -20, 40, 60, 25, 25, Qt.RelativeSize)
        painter.drawEllipse(-25, -20, 20, 20)
        painter.drawEllipse(5, -20, 20, 20)
        painter.drawEllipse(-20, 22, 20, 20)
        painter.drawEllipse(0, 22, 20, 20)


class RobotLimb(RobotPart):
    def boundingRect(self):
        return QRectF(-5, -5, 40, 10)

    def paint(self, painter, option, widget=None):
        painter.setBrush(self._drag_over and self.color.lighter(130) or self.color)
        painter.drawRoundedRect(self.boundingRect(), 50, 50,
                Qt.RelativeSize)
        painter.drawEllipse(-5, -5, 10, 10)


class Robot(RobotPart):
    def __init__(self):
        super().__init__()

        self.torsoItem         = RobotTorso(self)
        self.headItem          = RobotHead(self.torsoItem)
        self.upperLeftArmItem  = RobotLimb(self.torsoItem)
        self.lowerLeftArmItem  = RobotLimb(self.upperLeftArmItem)
        self._upper_right_arm_item = RobotLimb(self.torsoItem)
        self._lower_right_arm_item = RobotLimb(self._upper_right_arm_item)
        self._upper_right_leg_item = RobotLimb(self.torsoItem)
        self._lower_right_leg_item = RobotLimb(self._upper_right_leg_item)
        self.upperLeftLegItem  = RobotLimb(self.torsoItem)
        self.lowerLeftLegItem  = RobotLimb(self.upperLeftLegItem)

        self.timeline = QTimeLine()
        settings = [
        #             item               position    rotation at
        #                                 x    y    time 0  /  1
            ( self.headItem,              0,  -18,      20,   -20 ),
            ( self.upperLeftArmItem,    -15,  -10,     190,   180 ),
            ( self.lowerLeftArmItem,     30,    0,      50,    10 ),
            ( self._upper_right_arm_item,    15,  -10,     300,   310 ),
            ( self._lower_right_arm_item,    30,    0,       0,   -70 ),
            ( self._upper_right_leg_item,    10,   32,      40,   120 ),
            ( self._lower_right_leg_item,    30,    0,      10,    50 ),
            ( self.upperLeftLegItem,    -10,   32,     150,    80 ),
            ( self.lowerLeftLegItem,     30,    0,      70,    10 ),
            ( self.torsoItem,             0,    0,       5,   -20 )
        ]
        self.animations = []
        for item, pos_x, pos_y, rotation1, rotation2 in settings:
            item.setPos(pos_x,pos_y)
            animation = QGraphicsItemAnimation()
            animation.setItem(item)
            animation.setTimeLine(self.timeline)
            animation.setRotationAt(0, rotation1)
            animation.setRotationAt(1, rotation2)
            self.animations.append(animation)
        self.animations[0].setScaleAt(1, 1.1, 1.1)

        self.timeline.setUpdateInterval(1000 / 25)
        curve = QEasingCurve(QEasingCurve.SineCurve)
        self.timeline.setEasingCurve(curve)
        self.timeline.setLoopCount(0)
        self.timeline.setDuration(2000)
        self.timeline.start()

    def boundingRect(self):
        return QRectF()

    def paint(self, painter, option, widget=None):
        pass


if __name__== '__main__':
    app = QApplication(sys.argv)

    scene = QGraphicsScene(-200, -200, 400, 400)

    for i in range(10):
        item = ColorItem()
        angle = i * 2.0 * math.pi / 10.0
        item.setPos(math.sin(angle) * 150, math.cos(angle) * 150)
        scene.addItem(item)

    robot = Robot()
    robot.setTransform(QTransform().scale(1.2, 1.2))
    robot.setPos(0, -20)
    scene.addItem(robot)

    view = QGraphicsView(scene)
    view.setRenderHint(QPainter.Antialiasing)
    view.setViewportUpdateMode(QGraphicsView.BoundingRectViewportUpdate)
    view.setBackgroundBrush(QColor(230, 200, 167))
    view.setWindowTitle("Drag and Drop Robot")
    view.show()

    sys.exit(app.exec())
