from PIL import Image

''' Purpose: better experience functional development

    Email id: 
    Email id: 

    Pledge: All effort for this assignment has been done as team and when both
            the driver and navigator are present and working together
'''

# helpful constants
THRESHOLD = 85                # default max allowable distance to be similar
GREEN     = ( 0, 255, 0 )     # back screen color

def similar( p1, p2, max_allowable=THRESHOLD ) :
    ''' Returns whether the distance between pixels p1 and p2 is less than
        the max allowable threshold
    '''
    import color

    pass

def is_background( p, back_screen ) :
    ''' Returns whether p is similar to the back_screen color
    '''

    pass

def inbounds( spot,  img ) :
    ''' Returns whether spot lies on img.
    '''

    pass

def colorable( spot, img, p, back_screen ) :
    ''' Returns whether both spot is a location on img and color p is not
        similar to color back_screen
    '''

    pass

def combine( bg, fg, sx, sy, back_screen ) :
    ''' Returns mash up of background image bg and foreground image fg, where
        the pixels in fg that are dissimilar to back_screen are copied on top
        of the background.
    
        The mash up uses location (sx, sy) as the spot in the background to
        start the lay over of fg.
    '''

    bw, bh = bg.size
    fw, fh = fg.size

    new_image = bg.copy().convert( 'RGB' )

    for fx in range( 0, fw ) :
        for fy in range( 0, fh ):
            fspot = ( fx, fy )
            fpixel = fg.getpixel( fspot )

            bx = sx + fx
            by = sy + fy

            bspot = ( bx, by )

            if ( colorable( bspot, bg, fpixel, back_screen ) ) :
                new_image.putpixel( bspot, fpixel )

    return new_image

def clean_up( original, back_screen ) :
    ''' Returns a copy of original where pixels similar to the back_screen are set
        to the back_screen
    '''

    new_image = original.copy().convert( 'RGB' )

    nw, nh = new_image.size

    for nx in range( 0, nw ) :
        for ny in range( 0, nh ) :
            nspot = ( nx, ny )
            npixel = new_image.getpixel( nspot )

            if ( similar( npixel, back_screen ) ) :
                new_image.putpixel( nspot, back_screen )

    return new_image

if ( __name__ == '__main__' ) :

    import smashing

    smashing.test_with_dino()

    smashing.test_with_beyonce()

    smashing.test_with_ww()