from PyQt6.QtWidgets import QGraphicsScene, QGraphicsView, QSizePolicy
from PyQt6 import uic, QtGui, QtCore
from PyQt6.QtCore import Qt, QRect, QEvent, QCoreApplication
import math
#https://forum.qt.io/topic/93327/how-can-i-use-qpainter-to-paint-on-qgraphicsview/5
#https://www.pythonguis.com/tutorials/pyqt6-bitmap-graphics/#qpainter

# to solve the fit problem: https://stackoverflow.com/questions/61886358/qgraphicsview-fitinview-not-working-as-expected

DaySelectedEvent = QEvent.registerEventType()

class CalQGraphicsView(QGraphicsView):
    def __init__(self, scene):
        super().__init__(None)
        self.setScene(scene)
        self.setMouseTracking(True) # Allow to keep track of mouse location in the scene
        
    def resizeEvent(self, event):
        self.fitInView(self.sceneRect(), Qt.AspectRatioMode.IgnoreAspectRatio)

        
class CalDrawerScene(QGraphicsScene):
    def __init__(self, parent, env):
        self.parent=parent
        self.gridWidth=2
        self.daysLabelBG="#dddddd"
        self.eventsLabelBG="#36e364"
        super().__init__(None)
        self.showWeekends=True
        self.daysRect=list()
        self.eventsRect=list()
        self.mouseOver=-1
        self.env=env
        self.calState=env.calState
        self.daysNames=["Monday","Tuesday","Wednesday","Thursday","Friday","Saturday","Sunday"]
        self.pullState()
        self.selection=self.today

    def drawForeground(self, painter, rect):
        origXF, origYF, widthF, heightF = rect.getRect()
        origXI, origYI, widthI, heightI = (int(origXF),int(origYF),int(widthF),int(heightF))
        self.defaultBrush=painter.brush()
        self.daysRect.clear()
        self.eventsRect.clear()
        daysNamesH=self.drawDaysName(painter, origXI, origYI, widthI, heightI)
        self.drawGrid(painter, origXI, origYI+daysNamesH, widthI, heightI-daysNamesH)
        self.drawDaysLabel(painter)
        self.drawEvents(painter)

    def drawDaysName(self, painter, x, y, width, height):
        # Init Pen
        pen=QtGui.QPen()
        pen.setWidth(self.gridWidth)
        pen.setJoinStyle(Qt.PenJoinStyle.MiterJoin)
        po=int(self.gridWidth/2) # Pen offset
        painter.setPen(pen)
        # Init Brush
        painter.setBrush(Qt.BrushStyle.NoBrush)
        # Setup dimensions
        weekLength=7
        font=painter.font()
        metric=QtGui.QFontMetrics(font);
        labelH=metric.boundingRect("".join(self.daysNames)).height()
        margin=0
        offsetY=int(labelH/2)+int(labelH/4)+margin
        w=int((width-po*2)/weekLength)
        h=int(labelH)
        for i in range(0, 7):
            labelW=metric.boundingRect(self.daysNames[i]).width()
            offsetX=int(w/2-labelW/2)
#            painter.drawText(x+offsetX+w*i,y+offsetY,self.daysNames[i])
            painter.drawText(x+w*i,y,w,h,Qt.AlignmentFlag.AlignHCenter,self.daysNames[i])
            rect=QRect(x+po+w*i,y+po,w,h) # Draw grid
            painter.drawRect(rect)
        return labelH
        
    def drawGrid(self,painter, x, y, width, height):
        # Init Pen
        pen=QtGui.QPen()
        pen.setWidth(self.gridWidth)
        pen.setJoinStyle(Qt.PenJoinStyle.MiterJoin)
        po=int(self.gridWidth/2) # Pen offset
        painter.setPen(pen)
        # Init Brush
        brushHL=QtGui.QBrush()
        brushHL.setColor(QtGui.QColor("#e5e5e5"))
        brushHL.setStyle(Qt.BrushStyle.SolidPattern)
        painter.setBrush(Qt.BrushStyle.NoBrush)
        # Setup dimensions
        weekLength=7
        if not self.showWeekends:
            weekLength=5
        daysCount=weekLength*6


        # brush=QtGui.QBrush()
        # brush.setColor(QtGui.QColor("#0000FF"))
        # brush.setStyle(Qt.BrushStyle.SolidPattern)

        
        w=int((width-po*2)/weekLength)
        h=int((height-po*2)/6)
        row=0
        col=0
        self.daysRect.clear()
        while row*weekLength+col<daysCount:
            rect=QRect(x+po+w*col,y+po+row*h,w,h) # Draw grid
            rectInside=QRect(rect.x()+po,rect.y()+po,rect.width()-po*2,rect.height()-po*2) # Area within grid (within stroke)
            self.daysRect.append(rectInside) # Store this region for later drawing
            # if col==0 and row == 0:
            #     painter.setBrush(brush)
            #     painter.setPen(Qt.PenStyle.NoPen)
            #     painter.drawRect(QRect(b.x(),b.y(),b.width(),b.height()))
            #     painter.setPen(self.gridPen)
            #     painter.setBrush(self.defaultBrush)
            if row*weekLength+col == self.mouseOver:
                painter.setBrush(brushHL)
                painter.drawRect(rect)
                painter.setBrush(Qt.BrushStyle.NoBrush)
            else:
                painter.drawRect(rect)
            col+=1
            if col==weekLength:
                col=0
                row+=1

    def drawDaysLabel(self,painter):
        # Init Pen
        pen=QtGui.QPen()
        pen.setWidth(self.gridWidth)
        pen.setJoinStyle(Qt.PenJoinStyle.MiterJoin)
        po=int(self.gridWidth/2) # Pen offset
        # Init Brush
        brush=QtGui.QBrush()
        brush.setColor(QtGui.QColor(self.daysLabelBG))
        brush.setStyle(Qt.BrushStyle.SolidPattern)
        painter.setBrush(brush)
        # Init various things
        days=self.calState.getMonthDays()
        font=painter.font()
        metric=QtGui.QFontMetrics(font);
        labelH=metric.boundingRect("1234567890").height()
        margin=0
        offsetY=int(labelH/2)+int(labelH/4)+margin
        today=self.calState.today()
        # Draw labels
        for i in range(0,len(self.daysRect)):
            r=self.daysRect[i]
            d=days[i]
            dayLabel="["+str(d[2])+"]" if d == today else str(d[2])
            labelW=metric.boundingRect(dayLabel).width()
            offsetX=int(r.width()/2-labelW/2)
            painter.setPen(Qt.PenStyle.NoPen)
            painter.drawRect(r.x(),r.y(),r.width(),labelH) # Remember r is within grid stroke
            painter.setPen(pen)
#            painter.drawText(r.x()+offsetX,r.y()+offsetY,dayLabel)
            painter.drawText(r,Qt.AlignmentFlag.AlignHCenter,dayLabel)
            self.eventsRect.append(QRect(r.x(),r.y()+labelH+margin,r.width(),r.height()-(labelH+margin)))

    def drawEvents(self,painter):
        # Init Pen
        pen=QtGui.QPen()
        pen.setWidth(self.gridWidth)
        pen.setJoinStyle(Qt.PenJoinStyle.MiterJoin)
        po=int(self.gridWidth/2) # Pen offset
        # Init Brush
        brush=QtGui.QBrush()
        brush.setColor(QtGui.QColor(self.eventsLabelBG))
        brush.setStyle(Qt.BrushStyle.SolidPattern)
        painter.setBrush(brush)
        # Init various things
        days=self.calState.getMonthDays()
        font=painter.font()
        metric=QtGui.QFontMetrics(font);
        labelH=metric.height()
        margin=0
        colMark=5
        colMarkPadding=2
        offsetY=int(labelH/2)+int(labelH/4)+margin
        offsetX=colMark+colMarkPadding
        # Draw
        po=int(self.gridWidth/2) # Pen offset
        for i in range(0,len(self.eventsRect)):
            r=self.eventsRect[i]
            for e in self.events[i]:
                painter.drawText(r.x()+po+offsetX,r.y(),r.width()-offsetX-po*2,r.height(),0,"event testddddddddddddd")
                painter.setPen(Qt.PenStyle.NoPen)
                painter.drawRect(r.x(),r.y(),colMark,labelH) # Remember r is within grid stroke
                painter.setPen(pen)
            
    def mouseMoveEvent(self, event):
        """
        This is possible because of self.setMouseTracking(True) inside the view
        """
        pos=event.scenePos()
        x, y=(int(pos.x()),int(pos.y()))
        self.mouseOver=-1
        for i in range(0,len(self.daysRect)):
            r=self.daysRect[i]
            if r.contains(x,y):
                self.mouseOver=i
                self.update()
                event.accept()
                break

    def mousePressEvent(self, event):
        b=event.button()
        if self.mouseOver>=0 and b==Qt.MouseButton.LeftButton:
            event.accept()
            self.selection=self.calState.getMonthDays()[self.mouseOver]
            event = QEvent(DaySelectedEvent)
            QCoreApplication.postEvent(self.parent, event)

    def pullState(self):
        self.monthDays=self.calState.getMonthDays()
        self.today=self.calState.today()
        self.events=list()
        for yy, mm, dd, ww  in self.monthDays:
            self.events.append(self.env.listEventsOn(yy,mm,dd))

     
class CalDrawer():
    
    def __init__(self, parent, layout, env):
        self.env=env
        self.gs=CalDrawerScene(parent, env)
        self.gv=CalQGraphicsView(self.gs)
        # Setup propertion
        spLeft=QSizePolicy(QSizePolicy.Policy.Preferred,QSizePolicy.Policy.Preferred);
        spLeft.setHorizontalStretch(3);
        self.gv.setSizePolicy(spLeft);        

        # if jean:
        #     spLeft=QSizePolicy(QSizePolicy.Policy.Preferred,QSizePolicy.Policy.Preferred);
        #     spLeft.setHorizontalStretch(2);
        #     self.gv.setSizePolicy(spLeft);
        # else:
        #     spLeft=QSizePolicy(QSizePolicy.Policy.Preferred,QSizePolicy.Policy.Preferred);
        #     spLeft.setHorizontalStretch(1);
        #     self.gv.setSizePolicy(spLeft);
        layout.addWidget(self.gv)

    def getSelectionEvents(self):
        (yy,mm,dd,ww)=self.gs.selection
        return self.env.listEventsOn(yy,mm,dd)