import curses

inited = False
#default_color = False
default_color = True

def init():
    global colors, _colors, _pairs, attributes, inited, index
    if not inited:
        index = 1
        
        colors = { 'cyan': curses.COLOR_CYAN,
                   'green': curses.COLOR_GREEN,
                   'red': curses.COLOR_RED,
                   'yellow': curses.COLOR_YELLOW,
                   'blue': curses.COLOR_BLUE,
                   'magenta': curses.COLOR_MAGENTA,
                   'black': curses.COLOR_BLACK,
                   'white': curses.COLOR_WHITE }

        if default_color:
            colors["default"] = -1

        _colors = []
        _pairs = {}
    
        for key in _pairs:
            fg, bg = key
            curses.init_pair(index, colors[fg], colors[bg])
            _pairs[key] = curses.color_pair(index)
            _colors.append(key)
            index = len(_colors) + 1
            
        attributes = { 'bold': curses.A_BOLD,
                       'reverse': curses.A_REVERSE,
                       'normal': curses.A_NORMAL,
                       'underline': curses.A_UNDERLINE,
                       'dim': curses.A_DIM,
                       'standout': curses.A_STANDOUT }

        inited = True

def pairs(fg, bg):
    if not curses.has_colors():
        return curses.color_pair(0)
    
    global colors, _colors, _pairs, index
    key = (fg, bg)
    if key not in _pairs:
        assert index < curses.COLOR_PAIRS
        if not default_color:
            if fg == "default":
                fg = "white"
            if bg == "default":
                bg = "black"
        curses.init_pair(index, colors[fg], colors[bg])
        _pairs[key] = curses.color_pair(index)
        _colors.append(key)
        index = len(_colors) + 1
    return _pairs[key]

def get_pairs(index):
    if index == 0:
        return ('white', 'black')
    else:
        return _colors[index-1]

def reverse_colors(attr):
    return attr ^ curses.A_REVERSE

def build(fg, bg, *attr):
    cattr = pairs(fg, bg)
    return build_attr(cattr, *attr)

def build_attr(*attr):
    v = curses.A_NORMAL
    for x in attr:
        if type(x) == type(''):
            x = attributes[x]
        v = v | x
    return v