import type { Metadata } from 'next';
import Link from 'next/link';
import { notFound, permanentRedirect } from 'next/navigation';
import { ExternalLink } from 'lucide-react';
import { GraphLink } from '@/components/graph/graph-link';
import { PageHeader, Section, KV, Note } from '@/components/ui/section';
import { Badge, ClaimBadge, MatchBadge, StatusBadge } from '@/components/ui/badge';
import { EmptyState } from '@/components/ui/empty-state';
import { Freshness } from '@/components/ui/freshness';
import { SourceBadge } from '@/components/ui/source-badge';
import { JsonView } from '@/components/ui/json-view';
import { PublicationList } from '@/components/data/publication-list';
import { Pager } from '@/components/ui/pager';
import { getTrialByNct, trialConditionsFor, trialInterventionsFor, trialLocationsByCountry } from '@/lib/queries/trials';
import { publicationsForTrial, publicationsForTrialCount, PUBLICATION_PAGE_SIZE } from '@/lib/queries/publications';
import { fmtDate, fmtInt, humanize, phaseLabel } from '@/lib/format';
import { pageInfo } from '@/lib/pagination';
import { int, type SP } from '@/lib/search-params';

export const revalidate = 3600;

export async function generateMetadata({ params }: { params: Promise<{ nct: string }> }): Promise<Metadata> {
  const t = await getTrialByNct((await params).nct);
  return t ? { title: `${t.nct_id} — ${t.brief_title}`, description: t.brief_summary ? t.brief_summary.slice(0, 160) : `${t.nct_id}: status, phase, conditions, interventions, locations and references.`, alternates: { canonical: `/trial/${t.nct_id}` } } : { title: 'Trial' };
}

export default async function TrialPage({ params, searchParams }: { params: Promise<{ nct: string }>; searchParams: Promise<SP> }) {
  const { nct } = await params;
  const t = await getTrialByNct(nct);
  if (!t) notFound();
  if (t.nct_id !== nct) permanentRedirect(`/trial/${t.nct_id}`);
  const sp = await searchParams;
  const pubTotal = await publicationsForTrialCount(t.nct_id);
  const pp = pageInfo(int(sp, 'pPage', 1, 1, 100_000), PUBLICATION_PAGE_SIZE, pubTotal);
  const [conditions, interventions, locations, pubs] = await Promise.all([trialConditionsFor(t.id), trialInterventionsFor(t.id), trialLocationsByCountry(t.id), pubTotal ? publicationsForTrial(t.nct_id, { page: pp.page, pageSize: pp.pageSize }) : Promise.resolve([])]);
  const elig = t.eligibility ?? {};
  const eligText = typeof elig.criteria === 'string' ? elig.criteria : typeof elig.eligibilityCriteria === 'string' ? elig.eligibilityCriteria : null;

  return (
    <article>
      <PageHeader kicker={`Clinical trial · ${t.study_type ? humanize(t.study_type) : 'study'}`} title={t.brief_title} lede={t.official_title && t.official_title !== t.brief_title ? t.official_title : undefined}>
        <div className="mt-2 flex flex-wrap items-center gap-2 text-[12.5px]">
          <span className="ci-mono text-ink-2">{t.nct_id}</span>
          <span className="ci-mono text-ink-3">{t.id}</span>
          {t.acronym ? <Badge tone="outline">{t.acronym}</Badge> : null}
          <StatusBadge status={t.overall_status} />
          {t.phases.length ? <Badge>{t.phases.map(phaseLabel).join(' / ')}</Badge> : null}
          {t.has_results ? <Badge tone="ok">Results posted</Badge> : null}
          <a className="ci-link inline-flex items-center gap-1" href={`https://clinicaltrials.gov/study/${t.nct_id}`} target="_blank" rel="noopener noreferrer">
            ClinicalTrials.gov <ExternalLink className="h-3 w-3" aria-hidden />
          </a>
          <SourceBadge p={{ sourceSlug: 'clinicaltrials', sourceName: 'ClinicalTrials.gov', retrievedAt: t.updated_at, ingestRunId: t.ingest_run_id, layer: 'normalized' }} />
          <ClaimBadge kind="published" />
          <GraphLink type="trial" entityRef={t.nct_id} />
        </div>
        {t.why_stopped ? <Note tone="warn">Why stopped (as posted): {t.why_stopped}</Note> : null}
      </PageHeader>

      <div className="grid gap-8 lg:grid-cols-[1fr_340px]">
        <div className="space-y-8">
          {t.brief_summary ? (
            <Section id="summary" kicker="Summary" title="Brief summary (as posted)">
              <p className="max-w-3xl whitespace-pre-line text-[14.5px] leading-relaxed">{t.brief_summary}</p>
            </Section>
          ) : null}

          <Section id="conditions" kicker="Conditions" title={`Conditions (${fmtInt(conditions.length || t.conditions.length)})`} description="Free-text conditions as registered, with the CancerIndex entity they were reconciled to and the match type.">
            {conditions.length ? (
              <div className="ci-table-wrap">
                <table className="ci-table">
                  <thead>
                    <tr>
                      <th scope="col">Condition (as posted)</th>
                      <th scope="col">Mapped entity</th>
                      <th scope="col">Match</th>
                      <th scope="col" className="num">
                        Confidence
                      </th>
                    </tr>
                  </thead>
                  <tbody>
                    {conditions.map((c) => (
                      <tr key={c.normalized}>
                        <td>{c.condition_text}</td>
                        <td>
                          {c.cancer_slug ? (
                            <Link className="ci-link" href={`/cancer/${c.cancer_slug}/trials`}>
                              {c.cancer_name}
                            </Link>
                          ) : (
                            <span className="text-ink-3">—</span>
                          )}
                        </td>
                        <td>
                          <MatchBadge matchType={c.match_type} />
                        </td>
                        <td className="num">{c.confidence != null ? c.confidence.toFixed(2) : '—'}</td>
                      </tr>
                    ))}
                  </tbody>
                </table>
              </div>
            ) : t.conditions.length ? (
              <ul className="flex flex-wrap gap-1.5 text-[13.5px]">
                {t.conditions.map((c) => (
                  <li key={c} className="border border-rule px-2 py-0.5">
                    {c} <MatchBadge matchType="UNRESOLVED" className="ml-1" />
                  </li>
                ))}
              </ul>
            ) : (
              <EmptyState compact>No condition recorded.</EmptyState>
            )}
          </Section>

          <Section id="interventions" kicker="Interventions" title={`Interventions (${fmtInt(interventions.length || t.interventions.length)})`}>
            {interventions.length ? (
              <div className="ci-table-wrap">
                <table className="ci-table">
                  <thead>
                    <tr>
                      <th scope="col">Intervention</th>
                      <th scope="col">Type</th>
                      <th scope="col">Mapped drug</th>
                      <th scope="col">Match</th>
                    </tr>
                  </thead>
                  <tbody>
                    {interventions.map((i) => (
                      <tr key={i.name}>
                        <td>{i.name}</td>
                        <td>{i.intervention_type ? <Badge>{humanize(i.intervention_type)}</Badge> : '—'}</td>
                        <td>
                          {i.drug_slug ? (
                            <Link className="ci-link" href={`/drug/${i.drug_slug}`}>
                              {i.drug_name}
                            </Link>
                          ) : (
                            <span className="text-ink-3">—</span>
                          )}
                        </td>
                        <td>
                          <MatchBadge matchType={i.match_type} />
                        </td>
                      </tr>
                    ))}
                  </tbody>
                </table>
              </div>
            ) : t.interventions.length ? (
              <ul className="space-y-1 text-[13.5px]">
                {t.interventions.map((i, k) => (
                  <li key={`${i.name}-${k}`}>
                    <Badge className="mr-1">{humanize(i.type)}</Badge> {i.name}
                    {i.description ? <span className="block text-[12.5px] text-ink-3">{i.description}</span> : null}
                  </li>
                ))}
              </ul>
            ) : (
              <EmptyState compact>No intervention recorded.</EmptyState>
            )}
          </Section>

          {t.arms.length || t.primary_outcomes.length ? (
            <Section id="design" kicker="Design" title="Arms and outcomes">
              <div className="grid gap-4 md:grid-cols-2">
                <div>
                  <p className="ci-kicker mb-1">Arms ({t.arms.length})</p>
                  <JsonView data={t.arms} />
                </div>
                <div>
                  <p className="ci-kicker mb-1">Primary outcomes ({t.primary_outcomes.length})</p>
                  <JsonView data={t.primary_outcomes} />
                  {t.secondary_outcomes.length ? (
                    <details className="mt-2 text-[12.5px]">
                      <summary className="ci-link">Secondary outcomes ({t.secondary_outcomes.length})</summary>
                      <JsonView data={t.secondary_outcomes} />
                    </details>
                  ) : null}
                </div>
              </div>
            </Section>
          ) : null}

          <Section id="eligibility" kicker="Eligibility" title="Eligibility (as posted)">
            <KV items={[{ k: 'Sex', v: t.sex ? humanize(t.sex) : null }, { k: 'Minimum age', v: t.minimum_age }, { k: 'Maximum age', v: t.maximum_age }]} />
            {eligText ? (
              <details className="mt-3">
                <summary className="ci-link text-[13.5px]">Show eligibility criteria text</summary>
                <pre className="ci-code mt-2 whitespace-pre-wrap">{eligText}</pre>
              </details>
            ) : Object.keys(elig).length ? (
              <details className="mt-3">
                <summary className="ci-link text-[13.5px]">Show eligibility record</summary>
                <JsonView data={elig} />
              </details>
            ) : (
              <p className="mt-2 text-[13px] text-ink-3">No eligibility text recorded.</p>
            )}
          </Section>

          <Section id="references" kicker="References" title={`Publications (${fmtInt(pubTotal || t.references.length)})`}>
            {pubs.length ? (
              <>
                <PublicationList
                  rows={pubs}
                  summary={
                    <>
                      Showing {fmtInt(pp.from)}–{fmtInt(pp.to)} of {fmtInt(pubTotal)} indexed publications citing this registration
                    </>
                  }
                />
                <Pager total={pubTotal} pageSize={pp.pageSize} page={pp.page} hrefFor={(p) => `/trial/${t.nct_id}${p > 1 ? `?pPage=${p}` : ''}#references`} label="Publication pages" noun="publications" />
              </>
            ) : null}
            {t.references.length ? (
              <ul className="mt-2 space-y-1 text-[13px]">
                {t.references.map((r, i) => (
                  <li key={`${r.pmid ?? i}`} className="text-ink-2">
                    {r.type ? <Badge tone="outline" className="mr-1">{r.type}</Badge> : null}
                    {r.citation ?? ''}
                    {r.pmid ? (
                      <>
                        {' '}
                        <Link className="ci-mono ci-link" href={`/publication/${r.pmid}`}>
                          PMID {r.pmid}
                        </Link>
                      </>
                    ) : null}
                  </li>
                ))}
              </ul>
            ) : !pubs.length ? (
              <EmptyState compact>No reference posted for this study.</EmptyState>
            ) : null}
          </Section>
        </div>

        <aside className="space-y-8">
          <Section id="dates" kicker="Registry" title="Dates and enrollment" level={3}>
            <KV
              items={[
                { k: 'Start', v: fmtDate(t.start_date) },
                { k: 'Primary completion', v: fmtDate(t.primary_completion_date) },
                { k: 'Completion', v: fmtDate(t.completion_date) },
                { k: 'First posted', v: fmtDate(t.first_posted_date) },
                { k: 'Last update posted', v: fmtDate(t.last_update_posted_date) },
                { k: 'Results first posted', v: t.results_first_posted_date ? fmtDate(t.results_first_posted_date) : null },
                { k: 'Enrollment', v: t.enrollment_count != null ? <span className="ci-num">{fmtInt(t.enrollment_count)} {t.enrollment_type ? `(${t.enrollment_type.toLowerCase()})` : ''}</span> : null },
                { k: 'Lead sponsor', v: t.lead_sponsor ? <>{t.lead_sponsor} {t.lead_sponsor_class ? <Badge tone="outline">{t.lead_sponsor_class}</Badge> : null}</> : null },
                { k: 'Collaborators', v: t.collaborators.length ? t.collaborators.join('; ') : null },
                { k: 'Keywords', v: t.keywords.length ? t.keywords.join(', ') : null },
              ]}
            />
            <Freshness dataUpdatedAt={t.updated_at} sourceUpdatedAt={t.last_update_posted_date} extra="source: clinicaltrials" />
          </Section>
          <Section id="locations" kicker="Locations" title={`Locations by country (${fmtInt(t.locations_count)})`} level={3}>
            {locations.length ? (
              <div className="ci-table-wrap">
                <table className="ci-table">
                  <thead>
                    <tr>
                      <th scope="col">Country</th>
                      <th scope="col" className="num">
                        Sites
                      </th>
                      <th scope="col" className="num">
                        Recruiting
                      </th>
                    </tr>
                  </thead>
                  <tbody>
                    {locations.map((l) => (
                      <tr key={l.country}>
                        <td>{l.country}</td>
                        <td className="num">{fmtInt(l.n)}</td>
                        <td className="num">{fmtInt(l.recruiting)}</td>
                      </tr>
                    ))}
                  </tbody>
                </table>
              </div>
            ) : t.countries.length ? (
              <p className="text-[13.5px]">{t.countries.join(', ')}</p>
            ) : (
              <p className="text-[13px] text-ink-3">No location posted.</p>
            )}
          </Section>
          <Note tone="warn">Trial listing is informational. Eligibility is decided by the study team; contact information is on ClinicalTrials.gov.</Note>
        </aside>
      </div>
    </article>
  );
}