import type { Metadata } from 'next';
import Link from 'next/link';
import { PageHeader, 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 { recentApprovals, newPhase3Recruiting, trialPulseByPhase, newTrialsByCancer, rankingMoves, recentPublications, recentIngests, recentEvents } from '@/lib/queries/pulse';
import { fmtDate, fmtInt, fmtValue, humanize, phaseLabel, scopeLabel, truncate } from '@/lib/format';

export const metadata: Metadata = { title: 'Pulse — what changed in cancer', description: 'New oncology approvals, newly recruiting Phase III trials, registration momentum, ranking moves, recent publications and dataset updates — every item is a dated source record.' };
export const revalidate = 900;

const APPROVAL_DAYS = 90;
const TRIAL_DAYS = 30;
const PUB_DAYS = 60;

function Delta({ current, previous }: { current: number; previous: number }) {
  if (previous === 0) return <span className="text-ink-4" title="No studies in the previous window">—</span>;
  const pct = ((current - previous) / previous) * 100;
  const cls = pct > 0 ? 'text-ok' : pct < 0 ? 'text-danger' : 'text-ink-3';
  return (
    <span className={`ci-num ${cls}`} title={`${fmtInt(current)} vs ${fmtInt(previous)} in the previous ${TRIAL_DAYS} days`}>
      {pct > 0 ? '+' : ''}
      {pct.toFixed(0)} %
    </span>
  );
}

export default async function PulsePage() {
  const [approvals, phase3, pulse, byCancer, moves, pubs, ingests, events] = await Promise.all([recentApprovals(APPROVAL_DAYS, 40), newPhase3Recruiting(TRIAL_DAYS, 25), trialPulseByPhase(TRIAL_DAYS), newTrialsByCancer(TRIAL_DAYS, 10), rankingMoves(3, 20), recentPublications(PUB_DAYS, 15), recentIngests(14, 60), recentEvents(30, 30)]);
  const all = pulse.rows.find((r) => r.phase === 'ALL');
  const byAuthority = new Map<string, number>();
  for (const a of approvals) byAuthority.set(`${a.authority} · ${a.jurisdiction}`, (byAuthority.get(`${a.authority} · ${a.jurisdiction}`) ?? 0) + 1);
  const lastIngest = ingests.find((r) => r.status === 'succeeded' || r.status === 'partial');

  return (
    <div className="pb-8">
      <PageHeader kicker="Pulse" title="What changed in cancer" lede="A dated feed assembled from records already in the index: regulatory decisions, newly registered Phase III studies, registration momentum, ranking moves, recent publications and dataset refreshes. Nothing here is written by a model; every line links to its source record.">
        <p className="mt-3 flex flex-wrap items-center gap-2 text-[12.5px] text-ink-3">
          <ClaimBadge kind="observed" /> <ClaimBadge kind="regulatory" /> <ClaimBadge kind="computed" />
          <span>
            Windows: approvals {APPROVAL_DAYS} days · trials {TRIAL_DAYS} days · publications {PUB_DAYS} days · datasets 14 days.
          </span>
          <Link href="/data-updates" className="ci-link">
            Data update log →
          </Link>
          <Link href={`/year/${new Date().getUTCFullYear()}`} className="ci-link">
            Year in cancer →
          </Link>
        </p>
      </PageHeader>

      <div className="grid gap-10 lg:grid-cols-[1.35fr_1fr]">
        <div className="space-y-10">
          <Section id="approvals" kicker="Regulatory" title={`New oncology approval records (${fmtInt(approvals.length)})`} description={`Approval and marketing records dated within the last ${APPROVAL_DAYS} days, all authorities ingested. One line is one authority's decision for one application or product identifier; the cancer is shown only when the record names exactly one.`} actions={<Link href="/approvals" className="ci-link">All approvals →</Link>}>
            {approvals.length ? (
              <>
                <p className="mb-2 flex flex-wrap gap-1.5 text-[12px]">
                  {[...byAuthority.entries()].map(([k, n]) => (
                    <Badge key={k} tone="outline">
                      {k}: {fmtInt(n)}
                    </Badge>
                  ))}
                </p>
                <ul className="divide-y divide-rule text-[13.5px]">
                  {approvals.map((a) => (
                    <li key={a.id} className="grid gap-x-3 gap-y-0.5 py-2 sm:grid-cols-[92px_1fr]">
                      <span className="ci-mono text-[12px] text-ink-3">{fmtDate(a.approval_date)}</span>
                      <span className="min-w-0">
                        <Link href={`/drug/${a.drug_slug}`} className="ci-link font-medium">
                          {a.drug_name}
                        </Link>{' '}
                        <Badge tone="outline">
                          {a.authority} · {a.jurisdiction}
                        </Badge>{' '}
                        <StatusBadge status={a.status} />{' '}
                        {a.cancer_slug ? (
                          <Link href={`/cancer/${a.cancer_slug}`} className="ci-link">
                            {a.cancer_name}
                          </Link>
                        ) : a.tumor_agnostic ? (
                          <Badge tone="accent">tumor-agnostic</Badge>
                        ) : (
                          <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, 180)}
                        </span>
                        <span className="mt-0.5 flex items-center gap-1.5 text-[11.5px] text-ink-3">
                          {a.approval_type ? <span>{a.approval_type}</span> : null}
                          <SourceBadge p={{ sourceSlug: a.source_slug }} compact />
                        </span>
                      </span>
                    </li>
                  ))}
                </ul>
              </>
            ) : (
              <EmptyState compact title="No approval record dated in this window">Approval feeds are refreshed weekly (openFDA, Health Canada DPD); records appear here as soon as they carry a date within the window.</EmptyState>
            )}
          </Section>

          <Section id="phase3" kicker="Clinical research" title={`Newly registered Phase III studies now recruiting (${fmtInt(phase3.length)})`} description={`Interventional studies with Phase III among their phases, first posted on ClinicalTrials.gov in the last ${TRIAL_DAYS} days and recruiting. Cancer = first reconciled condition.`} actions={<Link href="/trials?status=RECRUITING&phase=PHASE3" className="ci-link">All recruiting Phase III →</Link>}>
            {phase3.length ? (
              <div className="ci-table-wrap">
                <table className="ci-table">
                  <thead>
                    <tr>
                      <th>First posted</th>
                      <th>NCT</th>
                      <th>Title</th>
                      <th>Cancer</th>
                      <th>Sponsor</th>
                      <th className="num">Enrollment (n)</th>
                    </tr>
                  </thead>
                  <tbody>
                    {phase3.map((t) => (
                      <tr key={t.id}>
                        <td className="whitespace-nowrap text-[12.5px]">{fmtDate(t.first_posted_date)}</td>
                        <td>
                          <Link href={`/trial/${t.nct_id}`} className="ci-mono ci-link">
                            {t.nct_id}
                          </Link>
                        </td>
                        <td className="min-w-[260px] max-w-[460px]">
                          <Link href={`/trial/${t.nct_id}`} className="text-ink no-underline hover:text-accent">
                            {t.brief_title}
                          </Link>
                          {t.acronym ? <span className="ml-1 text-[12px] text-ink-3">({t.acronym})</span> : null}
                        </td>
                        <td>{t.cancer_slug ? <Link href={`/cancer/${t.cancer_slug}`} className="ci-link">{t.cancer_name}</Link> : <span className="text-ink-4">unmapped</span>}</td>
                        <td className="max-w-[200px] truncate text-[12.5px]" title={t.lead_sponsor ?? ''}>
                          {t.lead_sponsor ?? '—'}
                          {t.lead_sponsor_class === 'INDUSTRY' ? <span className="ml-1 text-[11px] text-ink-3">industry</span> : null}
                        </td>
                        <td className="num">{t.enrollment_count == null ? '—' : fmtInt(t.enrollment_count)}</td>
                      </tr>
                    ))}
                  </tbody>
                </table>
              </div>
            ) : (
              <EmptyState compact title="No Phase III study first posted in this window">The ClinicalTrials.gov connector runs daily; newly posted studies appear after the next run.</EmptyState>
            )}
            <Freshness dataUpdatedAt={phase3[0]?.updated_at ?? null} extra="source: clinicaltrials · first_posted_date as posted by the registrant" />
          </Section>

          <Section id="moves" kicker="Rankings" title="Largest ranking moves" description="Top-level cancers whose rank changed by three places or more between the current snapshot and the previous one of the same metric and scope. A move usually follows a dataset refresh (new registry year, new trials) or a formula change; the ranking page explains each rank.">
            {moves.length ? (
              <div className="ci-table-wrap">
                <table className="ci-table">
                  <thead>
                    <tr>
                      <th>Metric</th>
                      <th>Scope</th>
                      <th>Cancer</th>
                      <th className="num">Rank</th>
                      <th className="num">Previous</th>
                      <th className="num">Value</th>
                      <th>Snapshot</th>
                    </tr>
                  </thead>
                  <tbody>
                    {moves.map((m) => (
                      <tr key={`${m.metric_slug}-${m.scope_key}-${m.cancer_id}`}>
                        <td>
                          <Link href={`/rankings/${m.metric_slug}?scope=${encodeURIComponent(m.scope_key)}`} className="ci-link">
                            {m.metric_name}
                          </Link>
                        </td>
                        <td className="text-[12px] text-ink-3">{scopeLabel(m.scope_key)}</td>
                        <td>
                          <Link href={`/cancer/${m.slug}/rankings`} className="ci-link">
                            {m.canonical_name}
                          </Link>
                        </td>
                        <td className="num font-medium">{m.rank}</td>
                        <td className="num">
                          {m.previous_rank} <span className={m.previous_rank > m.rank ? 'text-ok' : 'text-danger'}>{m.previous_rank > m.rank ? '▲' : '▼'}</span>
                        </td>
                        <td className="num">{fmtValue(m.value, m.unit)}</td>
                        <td className="whitespace-nowrap text-[12px] text-ink-3">{fmtDate(m.generated_at)}</td>
                      </tr>
                    ))}
                  </tbody>
                </table>
              </div>
            ) : (
              <EmptyState compact title="No ranking moved by three places or more">Ranks are compared with the previous snapshot of the same metric and scope; the first snapshot has no previous rank.</EmptyState>
            )}
          </Section>

          <Section id="publications" kicker="Literature" title={`Recently published records indexed (${fmtInt(pubs.length)})`} description={`PubMed records with a publication date in the last ${PUB_DAYS} days already linked to an index entity; randomized trials, systematic reviews and meta-analyses first. Publication dates are as recorded by PubMed.`}>
            {pubs.length ? (
              <ul className="divide-y divide-rule text-[13.5px]">
                {pubs.map((p) => (
                  <li key={p.id} className="grid gap-x-3 py-2 sm:grid-cols-[92px_1fr]">
                    <span className="ci-mono text-[12px] text-ink-3">{fmtDate(p.pub_date)}</span>
                    <span className="min-w-0">
                      <Link href={p.pmid ? `/publication/${p.pmid}` : '#'} className="ci-link">
                        {p.title}
                      </Link>
                      <span className="mt-0.5 flex flex-wrap items-center gap-1.5 text-[11.5px] text-ink-3">
                        {p.journal ? <span>{p.journal}</span> : null}
                        {p.publication_types.filter((t) => /trial|review|meta/i.test(t)).slice(0, 2).map((t) => (
                          <Badge key={t} tone="outline">
                            {t}
                          </Badge>
                        ))}
                        {p.pmid ? <span className="ci-mono">PMID {p.pmid}</span> : null}
                      </span>
                    </span>
                  </li>
                ))}
              </ul>
            ) : (
              <EmptyState compact title="No publication dated in this window">Literature is linked through entity queries (PubMed) and connector references; recent records appear after the nightly PubMed run.</EmptyState>
            )}
          </Section>
        </div>

        <aside className="space-y-10">
          <Section id="registrations" kicker="Momentum" title="Trial registrations, last 30 days" description="New oncology studies first posted on ClinicalTrials.gov per phase, compared with the preceding 30 days (all study types; a study with two phases counts in both).">
            {pulse.rows.length ? (
              <>
                {all ? (
                  <p className="mb-2 text-[13.5px]">
                    <span className="ci-num font-display text-2xl text-ink">{fmtInt(all.current)}</span> <span className="text-ink-2">new studies</span> <Delta current={all.current} previous={all.previous} />
                  </p>
                ) : null}
                <div className="ci-table-wrap">
                  <table className="ci-table">
                    <thead>
                      <tr>
                        <th>Phase</th>
                        <th className="num">Last 30 d</th>
                        <th className="num">Previous 30 d</th>
                        <th className="num">Change</th>
                      </tr>
                    </thead>
                    <tbody>
                      {pulse.rows
                        .filter((r) => r.phase !== 'ALL')
                        .map((r) => (
                          <tr key={r.phase}>
                            <td>{r.phase === 'NA' ? 'Not applicable' : phaseLabel(r.phase)}</td>
                            <td className="num">{fmtInt(r.current)}</td>
                            <td className="num">{fmtInt(r.previous)}</td>
                            <td className="num">
                              <Delta current={r.current} previous={r.previous} />
                            </td>
                          </tr>
                        ))}
                    </tbody>
                  </table>
                </div>
                <Freshness dataUpdatedAt={pulse.asOf} extra="trial_pulse · ci-trial-pulse-v1 · source: clinicaltrials" />
              </>
            ) : (
              <EmptyState compact title="Registration pulse not yet computed" />
            )}
          </Section>

          <Section id="by-cancer" kicker="Momentum" title="Most new studies by cancer" description="Top-level cancers by studies first posted in the last 30 days (conditions reconciled to the taxonomy, descendants included), with the preceding 30 days.">
            {byCancer.length ? (
              <div className="ci-table-wrap">
                <table className="ci-table">
                  <thead>
                    <tr>
                      <th>Cancer</th>
                      <th className="num">Last 30 d</th>
                      <th className="num">Previous</th>
                    </tr>
                  </thead>
                  <tbody>
                    {byCancer.map((c) => (
                      <tr key={c.id}>
                        <td>
                          <Link href={`/cancer/${c.slug}/trials`} className="ci-link">
                            {c.canonical_name}
                          </Link>
                        </td>
                        <td className="num">{fmtInt(c.current)}</td>
                        <td className="num text-ink-3">{fmtInt(c.previous)}</td>
                      </tr>
                    ))}
                  </tbody>
                </table>
              </div>
            ) : (
              <EmptyState compact title="Data not yet available" />
            )}
          </Section>

          <Section id="datasets" kicker="Data" title="Dataset refreshes, last 14 days" description="Connector runs (excluding dry runs and probes) with the number of source records created or updated and the dataset version reported by the source." actions={<Link href="/data-updates" className="ci-link">Full log →</Link>}>
            {ingests.length ? (
              <ul className="divide-y divide-rule text-[13px]">
                {ingests.slice(0, 12).map((r) => (
                  <li key={r.id} className="flex flex-wrap items-baseline justify-between gap-x-3 py-1.5">
                    <span className="min-w-0">
                      <Link href={`/source/${r.connector_id}`} className="ci-link">
                        {r.source_name ?? r.connector_id}
                      </Link>{' '}
                      <StatusBadge status={r.status} />
                      {r.dataset_version ? <span className="ci-mono ml-1 text-[11px] text-ink-3">{r.dataset_version}</span> : null}
                    </span>
                    <span className="ci-num text-[12px] text-ink-3">
                      {fmtDate(r.started_at)} · +{fmtInt(r.records_created)} / ~{fmtInt(r.records_updated)}
                    </span>
                  </li>
                ))}
              </ul>
            ) : (
              <EmptyState compact title="No connector run in the last 14 days" />
            )}
            <Freshness dataUpdatedAt={lastIngest?.finished_at ?? null} extra="ingest_runs" />
          </Section>

          <Section id="events" kicker="Changes" title="Entity change events" description="Non-bulk changes recorded by connectors in the last 30 days (approvals added, aliases, merges, deprecations).">
            {events.length ? (
              <ul className="divide-y divide-rule text-[13px]">
                {events.slice(0, 20).map((e) => (
                  <li key={e.id} className="py-1.5">
                    <span className="ci-mono mr-2 text-[11.5px] text-ink-3">{fmtDate(e.created_at)}</span>
                    <Badge tone="outline">{humanize(e.kind)}</Badge>{' '}
                    {e.entity_href ? (
                      <Link href={e.entity_href} className="ci-link">
                        {e.entity_name ?? e.entity_id}
                      </Link>
                    ) : (
                      <span>{e.entity_name ?? e.entity_id}</span>
                    )}
                    <span className="block text-[12px] text-ink-2">{truncate(e.summary, 160)}</span>
                  </li>
                ))}
              </ul>
            ) : (
              <EmptyState compact title="No non-bulk change event in the last 30 days" />
            )}
          </Section>
        </aside>
      </div>
      <div className="mt-8">
        <Note>Guideline changes, safety communications and trial-result events are not yet connected (no guideline or pharmacovigilance connector is live); this page will list them as event types once a licensed source is ingested. Nothing is inferred from press releases.</Note>
      </div>
    </div>
  );
}