const CHUNK_SIZE = 2000;
const CHUNK_OVERLAP = 200;

export function chunkText(text) {
    const cleaned = String(text || "").replace(/\r\n/g, "\n").trim();
    if (!cleaned) return [];
    if (cleaned.length <= CHUNK_SIZE) return [cleaned];

    const chunks = [];
    let start = 0;

    while (start < cleaned.length) {
        let end = Math.min(start + CHUNK_SIZE, cleaned.length);

        if (end < cleaned.length) {
            const slice = cleaned.slice(start, end);
            const lastBreak = Math.max(slice.lastIndexOf("\n"), slice.lastIndexOf(" "));
            if (lastBreak > CHUNK_SIZE * 0.5) {
                end = start + lastBreak;
            }
        }

        const chunk = cleaned.slice(start, end).trim();
        if (chunk) chunks.push(chunk);
        if (end >= cleaned.length) break;

        const nextStart = end - CHUNK_OVERLAP;
        start = nextStart <= start ? end : nextStart;
    }

    return chunks;
}