import { SITE_URL, SITE_NAME } from './site';
import { toDate } from './format';

/** Serialize JSON-LD safely for a <script type="application/ld+json"> block. */
export function jsonLd(obj: Record<string, unknown>): string {
  return JSON.stringify(obj).replace(/</g, '\\u003c');
}

/** Schema.org MedicalCondition — only fields we actually hold (§148). */
export function medicalConditionLd(c: { slug: string; canonicalName: string; description: string | null; aliases: string[]; codes: Array<{ system: string; code: string }> }) {
  const codeSystemName: Record<string, string> = { ncit: 'NCIt', icd10: 'ICD-10', icd10cm: 'ICD-10-CM', oncotree: 'OncoTree', doid: 'DOID', umls: 'UMLS', mesh: 'MeSH', mondo: 'MONDO' };
  const ld: Record<string, unknown> = {
    '@context': 'https://schema.org',
    '@type': 'MedicalCondition',
    name: c.canonicalName,
    url: `${SITE_URL}/cancer/${c.slug}`,
  };
  if (c.description) ld.description = c.description;
  if (c.aliases.length) ld.alternateName = c.aliases.slice(0, 20);
  const codes = c.codes.filter((k) => codeSystemName[k.system]).map((k) => ({ '@type': 'MedicalCode', codeValue: k.code, codingSystem: codeSystemName[k.system] }));
  if (codes.length) ld.code = codes;
  return ld;
}

export function drugLd(d: { slug: string; name: string; description: string | null; mechanism: string | null; aliases: string[] }) {
  const ld: Record<string, unknown> = { '@context': 'https://schema.org', '@type': 'Drug', name: d.name, url: `${SITE_URL}/drug/${d.slug}` };
  if (d.description) ld.description = d.description;
  if (d.mechanism) ld.mechanismOfAction = d.mechanism;
  if (d.aliases.length) ld.alternateName = d.aliases.slice(0, 20);
  return ld;
}

export function datasetLd(d: { name: string; description: string; url: string; distributionUrl: string; license: string; dateModified?: Date | string | null }) {
  const ld: Record<string, unknown> = {
    '@context': 'https://schema.org',
    '@type': 'Dataset',
    name: d.name,
    description: d.description,
    url: d.url,
    license: d.license,
    creator: { '@type': 'Organization', name: SITE_NAME, url: SITE_URL },
    distribution: [{ '@type': 'DataDownload', encodingFormat: 'text/csv', contentUrl: d.distributionUrl }],
  };
  const dm = toDate(d.dateModified);
  if (dm) ld.dateModified = dm.toISOString();
  return ld;
}