/**
 * Strip ANSI escape sequences, remove control characters / lone surrogates,
 * and normalize line endings.
 *
 * Bun-native implementation of the former native `sanitizeText` (see
 * `crates/pi-natives/src/text.rs::sanitize_text`). JavaScript strings are
 * already UTF-16 code-unit arrays. `toWellFormed()` handles the uncommon
 * malformed path; when it changes the input, replacement characters are
 * dropped and the normalized result goes through the well-formed sanitizer.
 *
 * Fast path: well-formed input with no controls or ANSI returns the original
 * string after the control probe.
 */

const ESC_CHAR = "\x1b";

// Well-formed strings only need control/ANSI detection: C0 (excl. \t \n),
// CR, DEL, and C1. ESC (0x1B) is in \x0B-\x1F.
const CONTROL_RE = /[\x00-\x08\x0B-\x1F\x7F-\x9F]/g;
const DISPLAY_FORMAT_RE = /[\u061C\u200E\u200F\u202A-\u202E\u2066-\u2069]/gu;

const REPLACEMENT_CHAR = "\ufffd";

export function sanitizeText(text: string): string {
	const wellFormed = text.toWellFormed();
	if (wellFormed !== text) {
		return sanitizeWellFormedText(wellFormed.replaceAll(REPLACEMENT_CHAR, ""));
	}
	return sanitizeWellFormedText(text);
}

/**
 * Sanitize untrusted text that must occupy exactly one rendered row.
 *
 * {@link sanitizeText} deliberately preserves `\n`, and width-based truncation
 * treats it as zero-width, so a value carrying line breaks can still inject
 * extra rows and evade a single-line width budget. Flatten every CR/LF run to a
 * single space before the usual control/ANSI strip, then remove directional
 * format controls that can visually reorder an otherwise safe row.
 */
export function sanitizeDisplayLine(text: string): string {
	return sanitizeText(text.replace(/[\r\n]+/gu, " ")).replace(DISPLAY_FORMAT_RE, "");
}

function sanitizeWellFormedText(text: string): string {
	CONTROL_RE.lastIndex = 0;
	if (CONTROL_RE.exec(text) === null) return text;

	const stripped = text.indexOf(ESC_CHAR) === -1 ? text : Bun.stripANSI(text);
	CONTROL_RE.lastIndex = 0;
	return stripped.replace(CONTROL_RE, "");
}