// Deterministic avatar palette + initials, used by feed cards and the account page.
// Dark variants are baked in so the palette reads correctly on both themes.

const PALETTE = [
	'bg-blue-100 text-blue-700 dark:bg-blue-900/40 dark:text-blue-200',
	'bg-purple-100 text-purple-700 dark:bg-purple-900/40 dark:text-purple-200',
	'bg-green-100 text-green-700 dark:bg-green-900/40 dark:text-green-200',
	'bg-amber-100 text-amber-700 dark:bg-amber-900/40 dark:text-amber-200',
	'bg-rose-100 text-rose-700 dark:bg-rose-900/40 dark:text-rose-200',
	'bg-teal-100 text-teal-700 dark:bg-teal-900/40 dark:text-teal-200'
];

const NEUTRAL = 'bg-gray-100 text-gray-500 dark:bg-gray-800 dark:text-gray-400';

export function avatarPalette(name: string | null | undefined): string {
	if (!name) return NEUTRAL;
	let hash = 0;
	for (const ch of name) hash = (hash * 31 + ch.charCodeAt(0)) & 0xff;
	return PALETTE[hash % PALETTE.length];
}

export function initials(name: string | null | undefined): string {
	if (!name) return '?';
	const words = name.trim().split(/\s+/).filter(Boolean);
	if (words.length === 0) return '?';
	if (words.length === 1) return words[0][0].toUpperCase();
	return (words[0][0] + words[1][0]).toUpperCase();
}