#!/usr/bin/python3
import tkinter as tk
from tkinter import ttk
import sys, os, json, traceback

################################################################################
# DEFINITIONS
################################################################################

EXIT_SUCCESS=0
EXIT_ERROR=1

default_configuration = {
    "window geometry": "640x480"
}

def warn(message, is_exception=False):
    print("WARNING: "+str(message), file=sys.stderr)
    if is_exception:
        traceback.print_exc()
    else:
        traceback.print_stack()

def error(message, is_exception=True, handle_gracefully=True):
    print("ERROR: "+str(message), file=sys.stderr)
    if is_exception:
        traceback.print_exc()
    else:
        traceback.print_stack()
    if handle_gracefully:
        pass
    else:
        sys.exit(EXIT_ERROR)

# easy way to get data out of window events
class Window_Interaction_Handler:
    # constructor
    def __init__(self):
        self.__window_interactions = {}

    # add a result for an interaction event, saves results in reverse order by default, can optionally call another function
    def interact(self, name, result, reverse_order=True, additional_action=None, additional_action_parameters=()):
        if name in self.__window_interactions:
            if reverse_order:
                self.__window_interactions[name] = [result] + self.__window_interactions[name]
            else:
                self.__window_interactions[name] = self.__window_interactions[name] + [result]
        else:
            self.__window_interactions[name] = [result]

        if not additional_action==None:
            additional_action(*additional_action_parameters)

    # get first result for a given event from the list of results (newest (default) or oldest), removes the returned result from the list by default
    def get_result(self, name, remove=True):
        if name in self.__window_interactions and len(self.__window_interactions[name])>0:
            if remove:
                result = self.__window_interactions[name].pop(0)
                if len(self.__window_interactions[name])==0:
                    del self.__window_interactions[name]
                return result
            else:
                return self.__window_interactions[name][0]
        else:
            return None

    # get all results for a given event
    def get_results(self, name, clear=False):
        if name in self.__window_interactions and len(self.__window_interactions[name])>0:
            results = self.__window_interactions[name]
            if clear:
                del self.__window_interactions[name]
            return results

    # clear results for a given event
    def clear(self, name):
        if name in self.__window_interactions:
            del self.__window_interactions[name]

    # destructor
    def __del__(self):
        if len(self.__window_interactions)>0:
            warn("__window_interactions not empty upon destruction of Window_Interaction_Handler:\n"+str(self.__window_interactions))

################################################################################
# PROGRAM START
################################################################################

# read configuration
home_directory = os.path.expanduser("~")
config_file_path = os.path.join(home_directory, "some_ide_config.json")
# load default configuration in case it is needed
configuration = default_configuration
if os.path.isfile(config_file_path):
    try:
        config_file = open(config_file_path, "r")
        configuration = json.loads(config_file.read())
        config_file.close()
    except Exception:
        error("An exception occurred while trying to load the configuration.", handle_gracefully=False)
else:
    # config not found
    dialog_interaction_handler = Window_Interaction_Handler()

    dialog = tk.Tk()
    dialog.title("No configuration found")
    ttk.Label(dialog, text="No configuration found!").pack()
    buttons_frame = tk.Frame(dialog)
    buttons_frame.pack()
    ttk.Button(buttons_frame, text="Create", command=lambda: dialog_interaction_handler.interact("create", True, additional_action=dialog.destroy)).grid(column=0, row=0)
    ttk.Button(buttons_frame, text="Quit", command=lambda: dialog_interaction_handler.interact("create", False, additional_action=dialog.destroy)).grid(column=1, row=0)
    dialog.resizable(0,0)
    dialog.mainloop()

    if dialog_interaction_handler.get_result("create"):
        try:
            config_file = open(config_file_path, "w")
            config_file.write(json.dumps(default_configuration))
            config_file.close()
        except:
            warn("Failed to save initial config file.", is_exception=True)
            dialog = tk.Tk()
            dialog.title("Failed to save initial config file")
            ttk.Label(dialog, text="Failed to save the initial config file. The IDE can still start up, but it is likely that all changes to the configuration will be lost where they would be saved otherwise.").pack()
            ttk.Button(dialog, text="Continue", command=dialog.destroy).pack()
            dialog.resizable(0,0)
            dialog.mainloop()
    else:
        error("No config present and user chose not to create one. Exiting.", is_exception=False, handle_gracefully=True)
        # exit with success exit code anyway because this is not a program failure
        sys.exit(EXIT_SUCCESS)


#window = tk.Tk()
#frame = ttk.Frame(window, padding=10)
#frame.grid()
#ttk.Label(frame, text="Hello, World!").grid(column=0, row=0)
#ttk.Button(frame, text="Quit", command=window.destroy).grid(column=0, row=1)

#window.mainloop()