/**
 * tokenize a command argument string, honoring double and single quotes so
 * args with spaces can come through as a single token.
 *
 *   parse('set "Solarized Dark"') -> ['set', 'Solarized Dark']
 *
 * an unterminated quote just runs to end-of-input (lenient, so someone
 * mid-typing never hits a hard error from the tokenizer itself).
 */
export function tokenize(input: string): string[] {
	const tokens: string[] = [];
	let current = '';
	let quote: '"' | "'" | null = null;
	let hasToken = false;

	for (let i = 0; i < input.length; i++) {
		const ch = input[i];
		if (quote) {
			if (ch === quote) {
				quote = null;
			} else {
				current += ch;
			}
			continue;
		}
		if (ch === '"' || ch === "'") {
			quote = ch;
			hasToken = true;
			continue;
		}
		if (ch === ' ' || ch === '\t') {
			if (hasToken) {
				tokens.push(current);
				current = '';
				hasToken = false;
			}
			continue;
		}
		current += ch;
		hasToken = true;
	}
	if (hasToken) tokens.push(current);
	return tokens;
}