import { EvidencePayload } from './types';

// Very forgiving parser: expects the assistant to include a JSON block delimited by ```json ... ```
// If no fenced block found, tries to JSON.parse the entire string.
export function tryParseEvidence(text: string): EvidencePayload | null {
  try {
    const fenceStart = text.indexOf('```json');
    const fenceEnd = text.indexOf('```', fenceStart + 7);
    const raw = fenceStart >= 0 && fenceEnd > fenceStart ? text.slice(fenceStart + 7, fenceEnd).trim() : text.trim();
    const obj = JSON.parse(raw);
    if (obj && obj.type === 'evidence' && Array.isArray(obj.claims)) {
      return obj as EvidencePayload;
    }
  } catch {}
  return null;
}