import tkinter

from tkinter import *
from tkinter.filedialog import asksaveasfilename
from tkinter.filedialog import askopenfilename

from PIL import Image

import urllib.request, io

import manip

# define globals and initialize
global canvas, image, tk_image, root, dialog

image    = None
canvas   = None
tk_image = None

def wrap_image_for_tkInter( img ):
    try:
        from PIL import ImageTk
        return ImageTk.PhotoImage(img)
    except:
        iname = "_photo-op-temporary.jpg"
        img.save(iname)
        return PhotoImage(file=iname)

def url_get_image( link ) :
    # returns the image at link

    stream = urllib.request.urlopen( link )

    data = stream.read()

    file = io.BytesIO( data )

    image = Image.open(file)

    image = image.convert('RGB')

    return image

def create_button( container, label, action ) :
    ''' return a new button stored in container whose contents is label, that when
        clicked performs action '''

    button = tkinter.Button( container , width=7, text=label )

    # button is to respond to a left click
    button.bind( '<Button-1>', action )

    # get button to arrange itself
    button.pack( padx=2, pady=5, side=LEFT )


    # hand back our new button

    return button

def open_file_click( event ) :
    ''' open an image '''

    global image, tk_image, canvas


    filename = askopenfilename()

    try :
        image = Image.open( filename )
    except :
        return

    image = image.convert('RGB')

    tk_image = wrap_image_for_tkInter( image )
    canvas.config( image=tk_image  )

def open_url_click( event ) :
    ''' open an image '''

    global image, tk_image, canvas, root, dialog

    input = Label( root, text="URL")
    input.pack()

    dialog = Entry(root)
    dialog.pack()

    b = Button(root, text="OK", command=dialog_click )
    b.pack()

def dialog_click( ) :
    global image, tk_image, canvas, root, dialog

    import urllib.request, io

    link = dialog.get()

    image = url_get_image( link )

    tk_image = wrap_image_for_tkInter( image )
    canvas.config( image=tk_image  )

def grey_click( event ) :
    global image, tk_image, canvas

    image = manip.greyscale( image )
    
    tk_image = wrap_image_for_tkInter( image )
    canvas.config( image=tk_image  )

def mirror_click( event ) :
    global image, tk_image, canvas

    image = manip.mirroring( image )

    tk_image = wrap_image_for_tkInter( image )
    canvas.config( image=tk_image  )

def cw_click( event ) :
    global image, tk_image, canvas

    image = manip.rotate( image )

    tk_image = wrap_image_for_tkInter( image )
    canvas.config( image=tk_image  )

def flip_click( event ) :
    global image, tk_image, canvas

    image = manip.flipping( image )

    tk_image = wrap_image_for_tkInter( image )
    canvas.config( image=tk_image  )

def sepia_click( event ) :
    global image, tk_image, canvas

    image = manip.sepia_tone( image )

    tk_image = wrap_image_for_tkInter( image )
    canvas.config( image=tk_image  )

def contrast_click( event ) :
    global image, tk_image, canvas

    image = manip.reduce_palette( image )

    tk_image = wrap_image_for_tkInter( image )
    canvas.config( image=tk_image  )

def mono_click( event ) :
    global image, tk_image, canvas

    image = manip.mono( image )

    tk_image = wrap_image_for_tkInter( image )
    canvas.config( image=tk_image  )
    canvas.config( image=tk_image  )

def zoom_in_click( event ) :
    global image, tk_image, canvas

    image = manip.zoom_in( image )

    tk_image = wrap_image_for_tkInter( image )
    canvas.config( image=tk_image  )
    canvas.config( image=tk_image  )

def zoom_out_click( event ) :
    global image, tk_image, canvas

    image = manip.zoom_out( image )

    tk_image = wrap_image_for_tkInter( image )
    canvas.config( image=tk_image  )
    canvas.config( image=tk_image  )


def pixelate_click( event ) :
    global image, tk_image, canvas

    import effect

    image = effect.blur( image )

    tk_image = wrap_image_for_tkInter( image )
    canvas.config( image=tk_image  )
    canvas.config( image=tk_image  )
def saveas_click( event ) :
    ''' save manipulation '''
    global image, tk_image, canvas

    filename = asksaveasfilename()

    image.save( filename )

def save_click( event ) :
    ''' save manipulation '''
    global image, tk_image, canvas

    image.save( filename, 'jpg' )

def create_edit_menu( container ) :

    menubar = tkinter.Menubutton( container, text='Commands' )
    menubar.grid()

    edit_menu = tkinter.Menu( menubar, tearoff=0 )

    edit_menu.add_command( label='Flip'           , command=flipping )
    edit_menu.add_command( label='Mirror'         , command=mirroring )
    edit_menu.add_command( label='Rotate'         , command=rotate )
    edit_menu.add_command( label='Grey scale'     , command=greyscale )
    edit_menu.add_command( label='Sepia'          , command=sepia_tone )
    edit_menu.add_command( label='Contrast'       , command=reduce_palette )
    #edit_menu.add_command( label='Revert'         , command=revert )
    menubar.pack()

    return menubar

def url_get( link ) :
    # returns the image at link

    stream = urllib.request.urlopen( link )

    data = stream.read()

    file = io.BytesIO( data )

    image = Image.open(file)

    image = image.convert('RGB')

    return image

def GUI( name='Photo Op', window_width=1000, window_height=900, bg='#4682B4' ) :
    global image, tk_image, canvas, root

    # define root window for the application
    root = Tk()

    # title the window
    root.title( name )

    # create the contain for the window content pane
    container = Frame( root, width=window_width, height=window_height, background=bg )

    # configure the container
    container.pack_propagate( 0 )

    container.pack()

    # start off with the mandrill image
    link = 'http://www.cs.virginia.edu/~cs1112/images/mandrill/full.jpg'
    image = url_get_image( link )

    # convert image from PIL format to tkinter format
    tk_image = wrap_image_for_tkInter( image )

    # create a label to be the canvas holding the image
    canvas = tkinter.Label(container, image=tk_image )

    # create a sub-container to hold the buttons
    buttons = LabelFrame( container, text='Image Operations', labelanchor=N, background="#4682B4"  )

    # create buttons for selecting photo operation
    open_file_button   = create_button( buttons, 'Open file',  open_file_click )
    saveas_button      = create_button( buttons, 'Save As',    saveas_click )
    flip_button        = create_button( buttons, 'Flip',       flip_click )
    mirror_button      = create_button( buttons, 'Mirror',     mirror_click )
    cw_button          = create_button( buttons, 'Rotate',     cw_click )
    sepia_button       = create_button( buttons, 'Sepia',      sepia_click )
    grey_button        = create_button( buttons, 'Grey',       grey_click )
    mono_button        = create_button( buttons, 'Mono',       mono_click )
    contrast_button    = create_button( buttons, 'Contrast',   contrast_click )
    zoom_in_button     = create_button( buttons, 'Zoom in',    zoom_in_click )
    zoom_out_button    = create_button( buttons, 'Zoom out',   zoom_out_click )
    pixelate_button    = create_button( buttons, 'Pixelate',   pixelate_click )
    #revert_button      = create_button( buttons, 'Revert',     revert_click )

    buttons.pack( pady=10 )

    # arrange the widgets in the window
    canvas.pack()

    # start event handling
    root.mainloop()

if ( __name__ == '__main__' ) :
    GUI()