from tkinter import Tk, Variable, Label, Button


from snap7 import Client, Area
from snap7.util import get_real, get_int


class PLC:
    def __init__(self):
        self.plc = Client()
        self.plc.connect("192.168.0.10", 0, 1)
    
    def __enter__(self):
        return self
    
    def __exit__(self, exc_type, exc, tb):
        self.plc.disconnect()
        self.plc.destroy()
    
    def update_variables(self, root: Tk, mm: Variable, raw: Variable):
        val_raw = get_int(self.plc.read_area(Area.PE, 0, 4, 2), 0)
        val_mm = get_real(self.plc.read_area(Area.MK, 0, 50, 4), 0)
        raw.set(f"Rohwert: {val_raw:>5d}")
        mm.set(f"Höhe: {val_mm:>4.1f} mm")
        root.after(10, self.update_variables, root, mm, raw)


def main(plc: PLC):
    root = Tk()
    root.title("Höhenmesser")
    mm = Variable(root, 0.0)
    raw = Variable(root, 0)
    Label(root, textvariable=mm, font=("JetBrains Mono", 36)).pack()
    Label(root, textvariable=raw, font=("JetBrains Mono", 36)).pack()
    Button(root, text="Verlassen", command=root.destroy, font=("Arial", 24)).pack()
    root.after(500, plc.update_variables, root, mm, raw)
    root.mainloop()


if __name__ == "__main__":
    with PLC() as plc:
        main(plc)