"""Basic GUI BoilerPlate

LICENSE AGREEMENT

The Original Code is "gui-boilerplate.py".

The Initial Developer of the Original Code is Leica Geosystems.
Portions created by Leica Geosystems are Copyright (C) 2014 year.
Leica Geosystems. All Rights Reserved.
"""

from Tkinter import *
import tkMessageBox
import tkFileDialog
import pprint

class BoilerPlateWindow:

    def __init__(self, command):
        self.command = command

        self.root = Tk()
        self.root.title("BoilerPlate")

        # bind in common events
        self.root.protocol("WM_DELETE_WINDOW", self.on_cancel)
        self.root.bind("<Escape>", self.on_cancel)
        self.root.bind("<Return>", self.on_ok)

        # TODO: insert your widgets

        # build the ok, apply cancel buttons
        self.buttonframe = Frame(self.root)
        self.buttonframe.pack(anchor='se', side='bottom')
        self.btn_ok = Button(self.buttonframe, text="OK",
                command=self.on_ok)
        self.btn_cancel = Button(self.buttonframe, text="CANCEL",
                command=self.on_cancel)
        self.btn_apply = Button(self.buttonframe, text="APPLY",
                command=self.on_apply)
        self.btn_cancel.pack(side='right', padx=2, pady=4)
        self.btn_apply.pack(side='right', padx=2, pady=4)
        self.btn_ok.pack(side='right', padx=2, pady=4)

    def start(self):
        self.root.mainloop()

    def on_cancel(self, event=None):
        self.root.destroy()

    def on_ok(self, event=None):
        self.freeze_dialog()
        if self.validate_input():
            self.call_business_layer()
        self.unfreeze_dialog()
        self.root.destroy()

    def on_apply(self, event=None):
        self.freeze_dialog()
        if self.validate_input():
            self.call_business_layer()
        self.unfreeze_dialog()

    def freeze_dialog(self):
        # TODO: disable your input widgets

        self.oldcursor = self.root.cget("cursor")
        self.root.configure(cursor="watch")
        self.root.update()

        self.btn_ok.configure(state=DISABLED)
        self.btn_cancel.configure(state=DISABLED)
        self.btn_apply.configure(state=DISABLED)
        self.root.update_idletasks()

    def unfreeze_dialog(self):
        # TODO: enable your input widgets

        self.root.configure(cursor=self.oldcursor)
        self.root.update()

        self.btn_ok.configure(state=ACTIVE)
        self.btn_cancel.configure(state=ACTIVE)
        self.btn_apply.configure(state=ACTIVE)
        self.root.update_idletasks()

    def validate_input(self):
        # TODO: validate input for your widgets. Return 1 if everything
        # is valid; return 0 otherwise. Also post error messages from
        # here, like this,
        # 
        #  tkMessageBox.showerror("your path is invalid!")
        #
        return 1

    def call_business_layer(self):
        # TODO: Compose your options and call the call back command if
        # there is one.
        options = {} # no 
        if self.command:
            self.command(self, options)

def callback(root, options):
    import time

    print pprint.pformat(options)
    print "processing...",
    time.sleep(2) # pretend to process really long
    print "ok."


if __name__=="__main__":
    window = BoilerPlateWindow(callback)
    window.start()