heading

import itertools
from rich.console import Console as RichConsole
from rich.text import Text as RichText
from typing import Union


flatten = itertools.chain.from_iterable


def heading(console: RichConsole, title: str) -> Union[str, RichText]:
    """
    XXX FIXME
    """
    left_edge, right_edge = RichText(" ║", "reverse"), RichText("║ ", "reverse")

    # Wrap title into lines if necessary, leaving minimal space required for
    # our decorations.
    min_text_width = 20
    min_decoration_width = len(f"{left_edge} {title} {right_edge}") - len(title)

    text_width = console.width - min_decoration_width

    # Console's not wide enough for our decorations, just skip 'em.
    if text_width < min_text_width:
        return title

    # Let's spruce up things around here.  Start by wrapping into lines since
    # our decoration involves surrounding the title and its appearance suffers
    # when the decoration itself wraps.
    lines = RichText(title).wrap(console, text_width)

    # Pad out each wrapped line to the same width so the right edge decorations
    # are aligned.
    for line in lines:
        line.rstrip()

    max_line_width = max(map(len, lines))

    for line in lines:
        line.pad_right(max_line_width - len(line))

    # Pad out right edge decoration, up to a point.
    right_edge.pad_right(min(60, console.width - min_decoration_width - max_line_width))

    # Assemble decorated lines
    return RichText.assemble(
        *flatten(
            (left_edge, " ", line, " ", right_edge, "\n")
                for line in lines))


if __name__ == "__main__":
    cons = RichConsole(markup = False)
    cons.print(heading(cons, "Checking for newer Nextstrain CLI version…"))