/** 笛卡尔积生成规格组合 */
export function buildSpecCombos(specs) {
	const groups = (specs || [])
		.map((s) => ({
			name: s.name,
			values: (s.values || []).filter((v) => v.selected)
		}))
		.filter((g) => g.values.length);
	if (!groups.length) return [];
	return groups.reduce(
		(acc, g) => {
			const next = [];
			acc.forEach((prev) => {
				g.values.forEach((v) => {
					next.push({
						label: prev.label ? `${prev.label} | ${v.name}` : v.name,
						keys: [...(prev.keys || []), v.id],
						price: '',
						sellingPrice: '',
						stock: '',
						costPrice: ''
					});
				});
			});
			return next;
		},
		[{ label: '', keys: [] }]
	);
}