# Main file of the program. Run this file to start the application.
# ToDo: improve performance, communication to PSUs is way too slow for dynamic field changes
# import packages:
from os.path import exists
import traceback
from tkinter import messagebox

# import other project files:
from src.helmholtz_cage_device import HelmholtzCageDevice
import src.globals as g
import src.config_handling as config
import src.csv_logging as log
from src.magnetometer import MagnetometerProxy
from src.user_interface import HelmholtzGUI, ExecuteCSVMode
from src.socket_control import SocketInterfaceThread
from src.utility import ui_print


def program_end():  # called on exception or when user closes application
    # safely shuts everything down and saves any unsaved data

    g.exitFlag = True  # tell everything else the application has been closed
    if g.app is not None:  # the main Tkinter app object has been initialized before
        if g.app.pages[ExecuteCSVMode].csv_thread is not None:  # check if a thread for executing CSVs exists
            g.app.pages[ExecuteCSVMode].csv_thread.stop()  # stop the thread

    g.CAGE_DEVICE.destroy()  # shut down devices and end all threads.

    if log.unsaved_data:  # Check if there is logged data that has not been saved yet
        # open pop-up to ask user if he wants to save the data:
        save_log = messagebox.askquestion("Save log data?", "There seems to be unsaved logging data. "
                                                            "Do you wish to write it to a file now?")
        if save_log == 'yes':  # user has chosen yes
            filepath = log.select_file()  # let user select a file to write to
            log.write_to_file(log.log_data, filepath)  # write the data to the chosen file

    if g.app is not None:
        g.app.destroy()  # close application


try:  # start normal operations

    config.CONFIG_FILE = 'config.ini'  # set the config file path
    # ToDo: remember what the last config file was
    if not exists(config.CONFIG_FILE):  # config file does not exist yet
        print("Config file not found, creating new from defaults.")
        config.reset_config_to_default()  # create configuration object from defaults
        config.write_config_to_file(config.CONFIG_OBJECT)  # write the configuration object to a new file

    config.CONFIG_OBJECT = config.get_config_from_file(config.CONFIG_FILE)  # read configuration data from config file

    print("Starting setup...")
    # initiate communication with devices and initialize all major program objects
    g.CAGE_DEVICE = HelmholtzCageDevice()
    # Mostly a data structure to hold field data broadcast by connected tcp client with HW access.
    g.MAGNETOMETER = MagnetometerProxy()

    print("\nOpening User Interface...")

    g.app = HelmholtzGUI()  # initialize user interface
    g.exitFlag = False  # tell all functions that the user interface is now running
    # g.app.state('zoomed')  # open UI in maximized window
    # g.app.StatusDisplay.continuous_label_update(g.app, 1000)  # initiate regular Status Display updates (ms)
    # ToDo: label update is very slow, commented out to save performance but should be implemented
    # ToDo!: csv thread + continuous label update seems to exceed capacity of PSU communication
    ui_print("Program Initialized")
    config.check_config(config.CONFIG_OBJECT)  # check config for values exceeding limits

    # Create TCP/Socket listener
    socket_controller = SocketInterfaceThread()
    socket_controller.start()

    g.app.protocol("WM_DELETE_WINDOW", program_end)  # call program_end function if user closes the application

    g.app.mainloop()  # start main program loop


except Exception as e:  # An error has occurred somewhere in the program
    print("\nAn error occurred, Shutting down.")
    # shop pup-up error message:
    message = "%s.\nSee python console traceback for more details. " \
              "\nShutting down devices, check equipment to confirm." % e
    messagebox.showerror("Error!", message)
    print(traceback.print_exc())  # print error traceback in the python console
    program_end()  # safely close everything and shut down devices