import Link from 'next/link';
import { Section, Note } from '@/components/ui/section';
import { EmptyState } from '@/components/ui/empty-state';
import { Freshness } from '@/components/ui/freshness';
import { Badge, ClaimBadge, StatusBadge } from '@/components/ui/badge';
import { SourceBadge } from '@/components/ui/source-badge';
import { countryTrialTotals, countrySitesByCancer, countrySitesByPhase, jurisdictionApprovalSummary, latestJurisdictionApprovals } from '@/lib/queries/country-activity';
import { fmtDate, fmtInt, fmtPct, phaseLabel, truncate } from '@/lib/format';

/** ISO 3166-1 alpha-2 codes that are also `drug_approvals.jurisdiction` codes. */
const JURISDICTIONS: Record<string, string> = { US: 'US', CA: 'CA', GB: 'UK', AU: 'AU', JP: 'JP', CH: 'CH' };

/**
 * Country research & regulatory activity (SPEC §22): trial sites in the country from ClinicalTrials.gov
 * locations (derived, formula ci-trial-sites-v1) and approval records for the country's regulator.
 * Rendered on every country page, including those without epidemiology observations.
 */
export async function CountryActivity({ iso2, iso3, name, kind }: { iso2: string | null; iso3: string | null; name: string; kind: string }) {
  if (kind !== 'country' || !iso3) return null;
  const jurisdiction = iso2 ? JURISDICTIONS[iso2] ?? null : null;
  const [totals, byCancer, byPhase, approvalSummary, latest] = await Promise.all([countryTrialTotals(iso3), countrySitesByCancer(iso3, 25), countrySitesByPhase(iso3), jurisdiction ? jurisdictionApprovalSummary(jurisdiction) : Promise.resolve([]), jurisdiction ? latestJurisdictionApprovals(jurisdiction, 10) : Promise.resolve([])]);

  return (
    <>
      <Section id="trial-activity" kicker="Clinical research" title={`Clinical trial activity in ${name}`} description="Registrant-entered study locations on ClinicalTrials.gov mapped to this country (any study type, any phase). A site is one location; a multi-site study weighs by its number of sites. Recruiting = location status RECRUITING, or the study status when the site has none." actions={<Link href={`/trials/map?recruiting=1`} className="ci-link">Trial map →</Link>}>
        {totals ? (
          <>
            <dl className="mb-3 grid grid-cols-2 gap-x-6 gap-y-2 text-[13.5px] sm:grid-cols-4">
              {[
                ['Sites', totals.sites],
                ['Studies with a site here', totals.trials],
                ['Recruiting sites', totals.recruiting_sites],
                ['Recruiting studies', totals.recruiting_trials],
              ].map(([k, v]) => (
                <div key={String(k)}>
                  <dt className="ci-kicker">{k}</dt>
                  <dd className="ci-num text-left font-display text-2xl">{fmtInt(v as number)}</dd>
                </div>
              ))}
            </dl>
            <div className="grid gap-6 lg:grid-cols-[3fr_2fr]">
              <div className="ci-table-wrap">
                <table className="ci-table">
                  <caption className="pb-1 text-[12.5px] text-ink-3">Top-level cancers by sites in {name} (descendants included)</caption>
                  <thead>
                    <tr>
                      <th>Cancer</th>
                      <th className="num">Sites</th>
                      <th className="num">Studies</th>
                      <th className="num">Recruiting studies</th>
                      <th className="num">Share of sites</th>
                    </tr>
                  </thead>
                  <tbody>
                    {byCancer.map((r) => (
                      <tr key={r.cancer_id}>
                        <td>
                          <Link href={`/cancer/${r.slug}/trials`} className="ci-link">
                            {r.canonical_name}
                          </Link>
                        </td>
                        <td className="num">{fmtInt(r.sites)}</td>
                        <td className="num">{fmtInt(r.trials)}</td>
                        <td className="num">{fmtInt(r.recruiting_trials)}</td>
                        <td className="num text-ink-3">{fmtPct(r.sites / totals.sites, 1)}</td>
                      </tr>
                    ))}
                  </tbody>
                </table>
              </div>
              <div className="ci-table-wrap">
                <table className="ci-table">
                  <caption className="pb-1 text-[12.5px] text-ink-3">By phase (a Phase II/III study counts in both)</caption>
                  <thead>
                    <tr>
                      <th>Phase</th>
                      <th className="num">Sites</th>
                      <th className="num">Studies</th>
                      <th className="num">Recruiting</th>
                    </tr>
                  </thead>
                  <tbody>
                    {byPhase.map((p) => (
                      <tr key={p.phase}>
                        <td>
                          <Link href={`/trials/map?phase=${p.phase}`} className="ci-link">
                            {phaseLabel(p.phase)}
                          </Link>
                        </td>
                        <td className="num">{fmtInt(p.sites)}</td>
                        <td className="num">{fmtInt(p.trials)}</td>
                        <td className="num">{fmtInt(p.recruiting_trials)}</td>
                      </tr>
                    ))}
                  </tbody>
                </table>
              </div>
            </div>
            <p className="mt-2 flex flex-wrap items-center gap-1.5 text-[11.5px] text-ink-3">
              <ClaimBadge kind="computed" /> <span>formula ci-trial-sites-v1 · source: clinicaltrials · shares are of sites, not of studies</span>
            </p>
            <Freshness dataUpdatedAt={totals.computed_at} extra="trial_site_country_counts" />
          </>
        ) : (
          <EmptyState compact title="No study location mapped to this country">Country aggregates exist for every country named in ClinicalTrials.gov locations; none names {name} yet, or the aggregate has not been computed.</EmptyState>
        )}
      </Section>

      {jurisdiction ? (
        <Section id="approvals" kicker="Regulatory" title={`Oncology approval records · ${jurisdiction}`} description="Records of the country's regulator as ingested (one record = one decision for one application or product identifier). Absence of a record here is not evidence of absence." actions={<Link href={`/approvals?jurisdiction=${jurisdiction}`} className="ci-link">All records →</Link>}>
          {approvalSummary.length ? (
            <>
              <p className="mb-2 flex flex-wrap gap-1.5 text-[12px]">
                {approvalSummary.map((s) => (
                  <Badge key={`${s.authority}-${s.status}`} tone="outline" title={`${s.drugs} distinct drugs · latest dated ${s.latest ?? '—'}`}>
                    {s.authority} · {s.status}: {fmtInt(s.n)} records / {fmtInt(s.drugs)} drugs
                  </Badge>
                ))}
              </p>
              <ul className="divide-y divide-rule text-[13.5px]">
                {latest.map((a) => (
                  <li key={a.id} className="grid gap-x-3 py-1.5 sm:grid-cols-[92px_1fr]">
                    <span className="ci-mono text-[12px] text-ink-3">{a.approval_date ? fmtDate(a.approval_date) : 'undated'}</span>
                    <span className="min-w-0">
                      <Link href={`/drug/${a.drug_slug}`} className="ci-link font-medium">
                        {a.drug_name}
                      </Link>{' '}
                      <StatusBadge status={a.status} />{' '}
                      {a.cancer_slug ? (
                        <Link href={`/cancer/${a.cancer_slug}`} className="ci-link">
                          {a.cancer_name}
                        </Link>
                      ) : (
                        <span className="text-ink-3">cancer not stated in this record</span>
                      )}
                      <span className="mt-0.5 block text-[12.5px] text-ink-2" title={a.indication}>
                        {truncate(a.indication, 140)}
                      </span>
                      <SourceBadge p={{ sourceSlug: a.source_slug }} compact />
                    </span>
                  </li>
                ))}
              </ul>
              <p className="mt-2">
                <ClaimBadge kind="regulatory" />
              </p>
            </>
          ) : (
            <EmptyState compact title="No approval record for this jurisdiction yet">Regulatory connectors are live for the FDA (US), Health Canada (CA) and the EMA (EU). Other regulators are not yet ingested.</EmptyState>
          )}
        </Section>
      ) : (
        <Note>Regulatory records are ingested per jurisdiction (US, CA, EU so far); {name} has no connected regulator yet.</Note>
      )}
    </>
  );
}