import { Section, Note } from '@/components/ui/section';
import { EmptyState } from '@/components/ui/empty-state';
import { Freshness } from '@/components/ui/freshness';
import { Pager } from '@/components/ui/pager';
import { EvidenceTable } from '@/components/data/evidence-table';
import { evidenceForCancer, evidenceForCancerCount, EVIDENCE_PAGE_SIZE } from '@/lib/queries/evidence';
import { loadProvenance } from '@/lib/queries/provenance';
import { fmtInt } from '@/lib/format';
import { pageInfo } from '@/lib/pagination';
import type { CancerBundle } from '../load';

export async function EvidenceTab({ b, evPage = 1 }: { b: CancerBundle; evPage?: number }) {
  const total = await evidenceForCancerCount(b.descendants);
  if (total === 0) {
    return (
      <Section id="evidence" kicker="Variants & evidence" title="Curated clinical evidence by variant and therapy">
        <EmptyState knows={[{ label: 'Genomics tab', href: `/cancer/${b.cancer.slug}/genomics` }, { label: 'Drugs tab', href: `/cancer/${b.cancer.slug}/drugs` }]}>
          No curated evidence item maps to this entity or its descendants. Evidence comes from CIViC and is displayed with its native level (A–E), direction (supports / does not support) and significance — never collapsed to a verdict.
        </EmptyState>
      </Section>
    );
  }
  const info = pageInfo(evPage, EVIDENCE_PAGE_SIZE, total);
  const items = await evidenceForCancer(b.descendants, { page: info.page, pageSize: info.pageSize });
  const prov = await loadProvenance(items.map((e) => e.provenance_id));
  const descendantItems = items.filter((e) => e.cancer_id !== b.cancer.id).length;
  const latest = items.reduce<Date | string | null>((m, e) => (m == null || String(e.updated_at) > String(m) ? e.updated_at : m), null);
  const hrefFor = (p: number) => `/cancer/${b.cancer.slug}/evidence${p > 1 ? `?evPage=${p}` : ''}`;
  return (
    <div className="space-y-6">
      <Section id="evidence" kicker="Variants & evidence" title="Curated clinical evidence by variant and therapy" description={`${fmtInt(total)} evidence items mapped to this entity or its descendants, grouped by molecular profile, then therapy. ${EVIDENCE_PAGE_SIZE} items per page.`}>
        <EvidenceTable
          items={items}
          prov={prov}
          showCancer={descendantItems > 0}
          summary={
            <>
              Showing {fmtInt(info.from)}–{fmtInt(info.to)} of {fmtInt(total)} evidence items
              {descendantItems ? ` (${fmtInt(descendantItems)} on this page mapped to a descendant entity)` : ''}
            </>
          }
        />
        <Pager total={total} pageSize={info.pageSize} page={info.page} hrefFor={hrefFor} label="Evidence pages" noun="evidence items" />
        <Freshness dataUpdatedAt={latest} extra="source: civic (CC0)" />
      </Section>
      <Note tone="warn">Evidence levels, directions and ratings are those assigned by CIViC curators. "Submitted" items have not completed curation review. This is not treatment guidance.</Note>
    </div>
  );
}