from tkinter import *


class Converter:

    def __init__(self):

        # common format for all buttons
        # Arial size 14 bold, with white text
        font_12_b = ("Arial", "12", "bold")
        font_16_b = ("Arial", "16", "bold")
        font_14 = ("Arial", "14")
        button_fg = "#FFFFFF"

        # Set up GUI Frame
        self.temp_frame = Frame(padx=10, pady=10)
        self.temp_frame.grid()

        self.temp_heading = Label(self.temp_frame,
                                  text="Temperature Convertor",
                                  font=font_16_b
                                  )
        self.temp_heading.grid(row=0)

        instructions = "Please enter a temperature below and " \
                       "then press one of the buttons to convert " \
                       "it from centigrade to Fahrenheit."
        self.temp_instructions = Label(self.temp_frame,
                                       text=instructions,
                                       wraplength=250, width=40,
                                       justify="left")
        self.temp_instructions.grid(row=1)

        self.temp_entry = Entry(self.temp_frame,
                                font=font_14
                                )
        self.temp_entry.grid(row=2, padx=10, pady=10)

        error = "Please enter a number"
        self.temp_error = Label(self.temp_frame, text="",
                                fg="#9C0000")
        self.temp_error.grid(row=3)

        # Conversion, help and history / export buttons
        self.button_frame = Frame(self.temp_frame)
        self.button_frame.grid(row=4)

        self.to_celsius_button = Button(self.button_frame,
                                        text="To Celsius",
                                        bg="#990099",
                                        fg=button_fg,
                                        font=font_12_b, width=12,
                                        command=self.to_celsius)
        self.to_celsius_button.grid(row=0, column=0, padx=5, pady=5)

        self.to_farenheit_button = Button(self.button_frame,
                                        text="To Farenheit",
                                        bg="#009900",
                                        fg=button_fg,
                                        font=font_12_b, width=12)
        self.to_farenheit_button.grid(row=0, column=1, padx=5, pady=5)

        self.to_help_button = Button(self.button_frame,
                                        text="Help / Info",
                                        bg="#CC6600",
                                        fg=button_fg,
                                        font=font_12_b, width=12)
        self.to_help_button.grid(row=1, column=0, padx=5, pady=5)

        self.to_history_button = Button(self.button_frame,
                                        text="History / Export",
                                        bg="#004C99",
                                        fg=button_fg,
                                        font=font_12_b, width=12,
                                        state=DISABLED)
        self.to_history_button.grid(row=1, column=1, padx=5, pady=5)


    def to_celsius(self):
        print("you pushed to celsius")

# main routine
if __name__ == "__main__":
    root = Tk()
    root.title("Temperature Converter")
    Converter()
    root.mainloop()