from PySide6.QtCore import QEvent, QObject, QPointF, QRect, QRectF, Qt
from PySide6.QtGui import QColor, QMouseEvent, QPaintEvent, QPainter, QPen
from PySide6.QtPdfWidgets import QPdfView
from PySide6.QtWidgets import QApplication, QWidget

def printParentHierarchy(obj: QObject, indent: int = 0):
    if obj:
        indentStr = '  ' * indent * 2
        print(f"{indentStr}{obj.metaObject().className()}:{obj.objectName()}")
        printParentHierarchy(obj.parent(), indent + 1)
    return
        
class scotusPdfView(QPdfView):

    drawing: bool
    start_point: QPointF
    end_point: QPointF
    
    def formatRect(self, rect: QRectF|QRect) -> str:
        return f"({rect.left()},{rect.top()}):({rect.right()},{rect.bottom()})"
    
    def __init__(self, parent: QWidget) -> None:
        self.drawing = False
        super(scotusPdfView, self).__init__(parent)
        print(self.viewport())
        return

    def paintEvent(self, event: QPaintEvent) -> None:
        super(scotusPdfView,self).paintEvent(event)
        if self.drawing:
            page = self.pageNavigator().currentPage()
            viewport = self.viewport()
            painter = QPainter(viewport)
            doc = self.document()
            dpi = QApplication.primaryScreen().logicalDotsPerInch()
            #
            # XXX: Our mouse events are storing coordinates in the "self"
            # coordinate system.  We need them in the viewport system
            #

            rect = QRectF(viewport.mapFrom(self, self.start_point),
                          viewport.mapFrom(self, self.end_point))
            redSolid = QPen(Qt.GlobalColor.red, 2, Qt.PenStyle.SolidLine)
            blueDash = QPen(Qt.GlobalColor.blue, 2, Qt.PenStyle.DashLine)
            greenDash = QPen(Qt.GlobalColor.green, 2, Qt.PenStyle.DashLine)
            painter.setPen(redSolid)
            painter.drawRect(rect) # Mouse drag box

            selectRect = QRectF(rect.left()/dpi*72,
                                rect.top()/dpi*72,
                                rect.right()/dpi*72,
                                rect.bottom()/dpi*72)
            painter.setPen(blueDash)
            selection = doc.getSelectionAtIndex(page, 10, 50)
            selection = doc.getSelection(page, selectRect.topLeft(), selectRect.bottomRight())
            bb = selection.boundingRectangle()
            painter.drawRect(bb) # Selection bounding box
            print(selection.text())
            print()

            painter.setPen(greenDash)
            bb.setLeft(bb.left()/72*dpi)
            bb.setTop(bb.top()/72*dpi)
            bb.setRight(bb.right()/72*dpi)
            bb.setBottom(bb.bottom()/72*dpi)
            painter.drawRect(bb) # Selection translated into viewport coordinates?
        return

    def mousePressEvent(self, event: QMouseEvent) -> None:
        if event.button() == Qt.MouseButton.LeftButton:
            self.start_point = event.pos()
            self.drawing = True
        return
    
    def mouseMoveEvent(self, event: QMouseEvent) -> None:
        if self.drawing:
            pos = event.pos()
            self.end_point = pos
            viewport = self.viewport()
            viewport.update()
        return

    def mouseReleaseEvent(self, event: QMouseEvent) -> None:
        if event.button() == Qt.MouseButton.LeftButton:
            self.drawing = False
            self.viewport().update()
        return