''' Purpose: support image bluing transformation
'''

def size( original ) :
    ''' Purpose: return the size of the new image when performing a bluing
    '''

    nw, nh = original.size # Extract width and height and just return it for the original size

    return (nw, nh)

def color( p ) :
    ''' Returns a new pixel whose RGB values are the inverse of pixel p,
        that is (255 - r, 255 - g, 255 - b), where r, g, and b are are
        the RGB values of pixel p
    '''
    r,g,b = p # Extract the original r, g, b values from the pixel p
    nr = 255 - r
    ng = 255 - g
    nb = 255 - b
    npixel = ( nr, ng, nb ) # New pixel we're returning with the new r,g,b amounts
    return npixel

def where( nspot, original = None ) :
    ''' Purpose: return the correspondent of nspot in the original when
            doing a bluing
    '''

    ospot = nspot   # Use the original spots

    return ospot

if ( __name__ == '__main__' ) :

    import url
    from manip import manip
    
    # get web image of interest
    link = "http://www.cs.virginia.edu/~cs1112/images/mandrill/full.png"

    original = url.get_image( link )

    new_image = manip( original, size, color, where )

    new_image.show()