import Link from 'next/link';
import { Section } from '@/components/ui/section';
import { EmptyState } from '@/components/ui/empty-state';
import { Freshness } from '@/components/ui/freshness';
import { ClaimBadge } from '@/components/ui/badge';
import { topPhase3Recruiting } from '@/lib/queries/trial-intelligence';
import { fmtInt, fmtPct, toDate } from '@/lib/format';
import { fmtGrowth } from '@/lib/trial-intel';

/**
 * Home module "Clinical trial intelligence" (SPEC §10): the top-level cancers with the most recruiting
 * Phase III interventional studies, with registration growth and industry share. Every figure comes from
 * `trial_intelligence` (computed, formula-versioned); nothing is shown until the layer has been computed.
 */
export async function TrialIntelModule({ limit = 8 }: { limit?: number }) {
  const rows = await topPhase3Recruiting(limit);
  const computedAt = rows.reduce<Date | null>((m, r) => {
    const d = toDate(r.computed_at);
    return d && (!m || d > m) ? d : m;
  }, null);
  return (
    <Section
      id="trial-intel"
      kicker="Clinical trials"
      title="Clinical trial intelligence"
      description="Top-level cancers with the most recruiting Phase III interventional studies, with the year-over-year change in registrations. Counts aggregate a cancer and its NCIt descendants; statuses and phases are as posted on ClinicalTrials.gov."
      actions={
        <Link href="/trials/intelligence" className="ci-link">
          All measures →
        </Link>
      }
    >
      {rows.length === 0 ? (
        <EmptyState title="Trial intelligence not yet computed">The per-cancer trial measures are derived from ClinicalTrials.gov records after each ingest. Nothing is shown until that computation has run.</EmptyState>
      ) : (
        <>
          <div className="ci-table-wrap">
            <table className="ci-table">
              <thead>
                <tr>
                  <th className="num">#</th>
                  <th>Cancer</th>
                  <th className="num" title="Recruiting interventional studies with PHASE3 among their phases">
                    Ph III recruiting
                  </th>
                  <th className="num" title="Active interventional studies (recruiting, not yet recruiting, enrolling by invitation, active not recruiting)">
                    Active
                  </th>
                  <th className="num" title="(studies first posted in the last 12 months − preceding 12 months) / preceding; null under 20 studies in the preceding window">
                    Growth YoY
                  </th>
                  <th className="num" title="Share of active studies led by an industry sponsor">
                    Industry
                  </th>
                </tr>
              </thead>
              <tbody>
                {rows.map((r, i) => (
                  <tr key={r.cancer_id}>
                    <td className="num">{i + 1}</td>
                    <td>
                      <Link className="ci-link" href={`/cancer/${r.cancer_slug}/trials`}>
                        {r.cancer_name}
                      </Link>
                    </td>
                    <td className="num font-medium">{fmtInt(r.phase3_recruiting)}</td>
                    <td className="num">{fmtInt(r.active_trials)}</td>
                    <td className={`num ${r.trial_growth_yoy != null && r.trial_growth_yoy > 0 ? 'text-ok' : r.trial_growth_yoy != null && r.trial_growth_yoy < 0 ? 'text-danger' : ''}`} title={`${fmtInt(r.new_trials_12m)} first posted in the last 12 months vs ${fmtInt(r.new_trials_prior_12m)} in the preceding 12 months`}>
                      {fmtGrowth(r.trial_growth_yoy)}
                    </td>
                    <td className="num">{fmtPct(r.industry_share, 0)}</td>
                  </tr>
                ))}
              </tbody>
            </table>
          </div>
          <p className="mt-1.5 flex flex-wrap items-center gap-1.5 text-[11.5px] text-ink-3">
            <ClaimBadge kind="computed" />
            <span>
              formula <span className="ci-mono">{rows[0]?.formula_version}</span> · interventional studies · descendants included
            </span>
            <span>source: clinicaltrials</span>
            <Link className="ci-link" href="/trials/terminated">
              Terminated studies
            </Link>
          </p>
          <Freshness dataUpdatedAt={computedAt} extra="computed by CancerIndex from ClinicalTrials.gov records" />
        </>
      )}
    </Section>
  );
}