import urwid
import urwid.display_common
from urwid import version


def _attrspec_to_escape_1_3_2(self, a):
    """
    Convert AttrSpec instance a to an escape sequence for the terminal

    >>> s = Screen()
    >>> s.set_terminal_properties(colors=256)
    >>> a2e = s._attrspec_to_escape
    >>> a2e(s.AttrSpec('brown', 'dark green'))
    '\\x1b[0;33;42m'
    >>> a2e(s.AttrSpec('#fea,underline', '#d0d'))
    '\\x1b[0;38;5;229;4;48;5;164m'
    """
    if self.term == 'fbterm':
        fg = escape.ESC + '[1;%d}' % (a.foreground_number,)
        bg = escape.ESC + '[2;%d}' % (a.background_number,)
        return fg + bg

    if a.foreground_high:
        fg = "38;5;%d" % a.foreground_number
    elif a.foreground_basic:
        if a.foreground_number > 7:
            if self.fg_bright_is_bold:
                fg = "1;%d" % (a.foreground_number - 8 + 30)
            else:
                fg = "%d" % (a.foreground_number - 8 + 90)
        else:
            fg = "%d" % (a.foreground_number + 30)
    else:
        fg = "39"
    st = ("1;" * a.bold + "3;" * a.italics +
          "4;" * a.underline + "5;" * a.blink +
          "7;" * a.standout + "9;" * a.strikethrough)
    if a.background_high:
        bg = "48;5;%d" % a.background_number
    elif a.background_basic:
        if a.background_number > 7:
            if self.bg_bright_is_blink:
                bg = "5;%d" % (a.background_number - 8 + 40)
            else:
                # this doesn't work on most terminals
                bg = "%d" % (a.background_number - 8 + 100)
        else:
            bg = "%d" % (a.background_number + 40)
    else:
        bg = "49"
    return urwid.escape.ESC + "[0;%s;%s%sm" % (fg, st, bg)


def _attrspec_to_escape_1_3_1(self, a):
    """
    Convert AttrSpec instance a to an escape sequence for the terminal

    >>> s = Screen()
    >>> s.set_terminal_properties(colors=256)
    >>> a2e = s._attrspec_to_escape
    >>> a2e(s.AttrSpec('brown', 'dark green'))
    '\\x1b[0;33;42m'
    >>> a2e(s.AttrSpec('#fea,underline', '#d0d'))
    '\\x1b[0;38;5;229;4;48;5;164m'
    """
    if a.foreground_high:
        fg = "38;5;%d" % a.foreground_number
    elif a.foreground_basic:
        if a.foreground_number > 7:
            if self.fg_bright_is_bold:
                fg = "1;%d" % (a.foreground_number - 8 + 30)
            else:
                fg = "%d" % (a.foreground_number - 8 + 90)
        else:
            fg = "%d" % (a.foreground_number + 30)
    else:
        fg = "39"
    st = ("1;" * a.bold + "3;" * a.italics +
          "4;" * a.underline + "5;" * a.blink +
          "7;" * a.standout + "9;" * a.strikethrough)
    if a.background_high:
        bg = "48;5;%d" % a.background_number
    elif a.background_basic:
        if a.background_number > 7:
            if self.bg_bright_is_blink:
                bg = "5;%d" % (a.background_number - 8 + 40)
            else:
                # this doesn't work on most terminals
                bg = "%d" % (a.background_number - 8 + 100)
        else:
            bg = "%d" % (a.background_number + 40)
    else:
        bg = "49"
    return urwid.escape.ESC + "[0;%s;%s%sm" % (fg, st, bg)


def _add_italics(version):
    def _foreground(self):
        return urwid.display_common.AttrSpec._foreground(self) + (',italics' * urwid.display_common.AttrSpec.italics,)

    urwid.display_common._ITALICS = 0x20000000
    urwid.display_common._FG_MASK |= urwid.display_common._ITALICS
    urwid.display_common._ATTRIBUTES['italics'] = urwid.display_common._ITALICS
    urwid.display_common.AttrSpec.italics = property(lambda s: s._value & urwid.display_common._ITALICS != 0)

    if version <= (1, 3, 1):
        urwid.raw_display.Screen._attrspec_to_escape = _VERSIONED_REPLACEMENTS['_attrspec_to_escape']['1.3.1']
    else:
        urwid.raw_display.Screen._attrspec_to_escape = _VERSIONED_REPLACEMENTS['_attrspec_to_escape']['1.3.2']


def _add_strikethrough(version):
    def _foreground(self):
        return urwid.display_common.AttrSpec._foreground(self) + (',strikethrough' * urwid.display_common.AttrSpec.strikethrough,)

    urwid.display_common._STRIKETHROUGH = 0x40000000
    urwid.display_common._FG_MASK |= urwid.display_common._STRIKETHROUGH
    urwid.display_common._ATTRIBUTES['strikethrough'] = urwid.display_common._STRIKETHROUGH
    urwid.display_common.AttrSpec.strikethrough = property(lambda s: s._value & urwid.display_common._STRIKETHROUGH != 0)
    urwid.display_common.AttrSpec._foreground = _foreground

    if version <= (1, 3, 1):
        urwid.raw_display.Screen._attrspec_to_escape = _VERSIONED_REPLACEMENTS['_attrspec_to_escape']['1.3.1']
    else:
        urwid.raw_display.Screen._attrspec_to_escape = _VERSIONED_REPLACEMENTS['_attrspec_to_escape']['1.3.2']


def patch_urwid():
    need_features = set()

    # Not in the urwid upstream tree
    need_features.add('strikethrough')

    # Currently in the urwid tree but not yet released
    if version.VERSION < (1, 3, 1):
        need_features.add('italics')

    for feature in need_features:
        _FEATURE_DISPATCH[feature](version.VERSION)


_VERSIONED_REPLACEMENTS = {'_attrspec_to_escape': {'1.3.1': _attrspec_to_escape_1_3_1,
                                                   '1.3.2': _attrspec_to_escape_1_3_2,}}
_FEATURE_DISPATCH = {'strikethrough': _add_strikethrough,
                     'italics': _add_italics}