# convert_gui.py
#
# Program to convert Celsius to Fahrenheit
# using Zelle's graphical package; 
# code from Zelle's Python textook
#

from graphics import *

def main():
    win = GraphWin("Celsius Converter", 400, 300)
    win.setCoords(0.0, 0.0, 3.0, 4.0)
    
    # Draw the interface
    Text(Point(1,3), "   Celsius Temperature:").draw(win)
    Text(Point(1,1), "Fahrenheit Temperature:").draw(win)
    input = Entry(Point(2,3), 5)
    input.setText("0.0")
    input.draw(win)
    output = Text(Point(2,1),"")
    output.draw(win)
    button = Text(Point(1.5,2.0),"Convert It")
    button.draw(win)
    Rectangle(Point(1,1.5), Point(2,2.5)).draw(win)

    # wait for a mouse click
    win.getMouse()

    # convert input
    celsius = eval(input.getText())
    fahrenheit = 9.0/5.0 * celsius + 32

    # display output and change button
    output.setText("{:0.1f}".format(fahrenheit))
    button.setText("Quit")

    # wait for click and then quit
    win.getMouse()
    win.close()
    
main()