---
import type { HTMLAttributes } from 'astro/types';
import { LOCALES } from '~/consts';

type Props = HTMLAttributes<'a'>;

const { href, class: className, ...props } = Astro.props;

function stripTrailing(p: string) {
	return p.length > 1 && p.endsWith('/') ? p.slice(0, -1) : p;
}

function stripBase(p: string) {
	const base = import.meta.env.BASE_URL;
	if (base && base !== '/' && p.startsWith(base)) return p.slice(base.length - 1) || '/';
	return p;
}

const pathname = stripTrailing(stripBase(Astro.url.pathname));
const target = stripTrailing(String(href ?? ''));

// Locale home URLs (`/`, `/en`) should only activate on exact match; deeper
// routes activate when the pathname equals or is nested under the href.
const localeHomes = new Set(['/', ...LOCALES.map((l) => `/${l}`)]);
const isActive = localeHomes.has(target)
	? pathname === target
	: pathname === target || pathname.startsWith(target + '/');
---

<a href={href} class:list={[className, { active: isActive }]} {...props}>
	<slot />
</a>
<style>
	a {
		display: inline-block;
		text-decoration: none;
	}
	a.active {
		font-weight: bolder;
		text-decoration: underline;
	}
</style>