#!/usr/bin/env python3
from tkinter import *
from tkinter import ttk
from time import time

# --------------------------
# Model
# --------------------------
class StopWatch:
    def __init__(self):
        self.seconds = 0.00
        self.starttime = 0.00
        self.running = False
    
    def switch(self):
        if not self.running:
            self.start()
        else:
            self.stop()
        return self.running

    def start(self):
        self.starttime = time()
        self.running = True
            
    def stop(self):
        self.seconds = time() - self.starttime
        self.running = False
            
    def print_status(self):
        if self.running:
            print("Uhr läuft.")
        else:
            print("Uhr angehalten.")
        
    def get_time(self):
        if not self.running:
            return self.seconds
        else:
            return False
    
# --------------------------
# Controller
# --------------------------
class WatchController:
    def __init__(self, app):
        self.app = app
        self.sw = StopWatch()
        
    def switch_clock(self, event=None):
        running = self.sw.switch()
        if running:
            stoppedtime = 0
        else:
            stoppedtime = self.sw.get_time()
        self.update_view(running, self.sw.get_time())
        
    def update_view(self, running, stoppedtime):
        self.app.update(running, stoppedtime)

# --------------------------
# View / Main Application
# --------------------------
class StopWatch_App(Tk):
    def __init__(self):
        super().__init__()
        self.controller = WatchController(self)
        self.create_control_variables()
        self.create_widgets()
        self.bind_events()
        
    def create_control_variables(self):
        self.btext = StringVar()
        self.btext.set("Start")
        self.etext = StringVar()
        self.etext.set("0.00")
        
    def create_widgets(self):
        mainframe = ttk.Frame(self, padding="3 3 3 3")
        mainframe.grid(column=0, row=0, sticky=N+W+S+E)
        self.columnconfigure(0, weight=1)
        self.rowconfigure(0, weight=1)
        self.button_switch = ttk.Button(mainframe, textvariable=self.btext, command=self.controller.switch_clock)
        self.button_switch.grid(column=0, row=0, sticky=W)
        self.entry_time = ttk.Entry(mainframe, state="readonly", textvariable=self.etext)
        self.entry_time.grid(column=1, row=0, sticky=W)
        
    def bind_events(self):
        self.bind("<Return>", self.controller.switch_clock)
    
    def update(self, running, stoppedtime):
        if running:
            self.btext.set("Stopp")
            self.etext.set("running...")
        else:
            self.etext.set("{:2.3f}".format(stoppedtime))
            self.btext.set("Start")
        
# --------------------------
# Execution
# --------------------------
if __name__ == "__main__":
    app = StopWatch_App()
    app.mainloop()