import { PageHeader } from "@/components/PageHeader";
import { RecordLink } from "@/components/RecordLink";
import type { EntityView, RelationItem } from "@/lib/catalog";

/**
 * Generic record page: title, summary, sources, claims, and neighbouring relations.
 * OnCo EntityDetail was not copied. That file special-cases domain panels.
 */

function RelationBlock({
  headingId,
  title,
  relations,
}: {
  headingId: string;
  title: string;
  relations: RelationItem[];
}) {
  return (
    <section aria-labelledby={headingId}>
      <h2 id={headingId} className="mb-3 text-lg">{title}</h2>
      {relations.length === 0 ? (
        <p className="text-sm text-muted">No {title.toLowerCase()} relations.</p>
      ) : (
        <ul className="space-y-2 text-sm">
          {relations.map((relation) => (
            <li key={relation.id} data-relation={relation.id} data-direction={relation.direction}>
              <span className="text-muted">{relation.wording}</span>
              {" · "}
              <RecordLink link={relation.other} />
            </li>
          ))}
        </ul>
      )}
    </section>
  );
}

export function EntityDetail({ entity }: { entity: EntityView }) {
  const currentIndex = entity.readingPath.findIndex((step) => step.id === entity.id);
  return (
    <>
      <PageHeader kicker={entity.kindLabel} title={entity.title} lede={entity.tldr} />
      <div className="mx-auto max-w-7xl space-y-10 px-4 py-10 sm:px-6">
        {entity.glossary ? (
          <p className="glossary" data-glossary={entity.glossary}>
            <span className="glossary-tip" role="tooltip">{entity.glossary}</span>
          </p>
        ) : null}
        <p className="max-w-3xl text-body leading-relaxed">{entity.summary}</p>
        {entity.tags.length > 0 ? (
          <ul className="flex flex-wrap gap-2">
            {entity.tags.map((tag) => (
              <li key={tag} className="chip">{tag}</li>
            ))}
          </ul>
        ) : null}
        {entity.readingPath.length > 0 ? (
          <nav aria-label="Reading path">
            <ol className="flex flex-wrap gap-2 text-sm">
              {entity.readingPath.map((step, index) => {
                const current = step.id === entity.id;
                const earlier = currentIndex >= 0 && index < currentIndex;
                return (
                  <li key={`${step.id}:${index}`}>
                    {index > 0 ? <span className="text-muted"> / </span> : null}
                    {current ? (
                      <span aria-current="page">{step.title}</span>
                    ) : earlier || step.href ? (
                      <a className="underline" href={step.href ?? "#"}>{step.title}</a>
                    ) : (
                      <span>{step.title}</span>
                    )}
                  </li>
                );
              })}
            </ol>
          </nav>
        ) : null}
        <section aria-labelledby="sources-heading">
          <h2 id="sources-heading" className="mb-3 text-lg">Sources</h2>
          {entity.sources.length === 0 ? (
            <p className="text-sm text-muted">No sources.</p>
          ) : (
            <ul className="space-y-2 text-sm">
              {entity.sources.map((source) => (
                <li key={source.title}>
                  {source.title}
                  {source.license ? <span className="text-muted"> · {source.license}</span> : null}
                </li>
              ))}
            </ul>
          )}
        </section>
        <section aria-labelledby="claims-heading">
          <h2 id="claims-heading" className="mb-3 text-lg">Claims</h2>
          {entity.claims.length === 0 ? (
            <p className="text-sm text-muted">No claims.</p>
          ) : (
            <ul className="space-y-2 text-sm">
              {entity.claims.map((claim) => (
                <li key={`${claim.key}:${claim.status}:${claim.value ?? ""}`}>
                  <span className="font-medium">{claim.key}</span>
                  <span className="text-muted"> · {claim.status}</span>
                  {claim.value ? <span> · {claim.value}</span> : null}
                </li>
              ))}
            </ul>
          )}
        </section>
        <section aria-labelledby="relations-heading" className="space-y-6">
          <h2 id="relations-heading" className="text-lg">Relations</h2>
          <RelationBlock headingId="outgoing-relations" title="Outgoing" relations={entity.outgoing} />
          <RelationBlock headingId="incoming-relations" title="Incoming" relations={entity.incoming} />
          {entity.relationRemainder > 0 ? (
            <p data-relation-remainder={entity.relationRemainder}>
              {entity.relationRemainder} more relations are not listed.
            </p>
          ) : null}
        </section>
        {entity.collection ? (
          <section aria-labelledby="collection-heading">
            <h2 id="collection-heading" className="mb-3 text-lg">{entity.collection.title}</h2>
            {entity.collection.members.length === 0 ? (
              <p className="text-sm text-muted">No members.</p>
            ) : (
              <ul className="space-y-2 text-sm">
                {entity.collection.members.map((member) => (
                  <li key={member.id}>
                    <RecordLink link={member} />
                  </li>
                ))}
              </ul>
            )}
          </section>
        ) : null}
        {entity.related.length > 0 ? (
          <section aria-labelledby="related-heading">
            <h2 id="related-heading" className="mb-3 text-lg">Related</h2>
            <ul className="space-y-2 text-sm">
              {entity.related.map((item) => (
                <li key={item.id}>
                  <RecordLink link={item} />
                </li>
              ))}
            </ul>
          </section>
        ) : null}
        <p className="text-sm">
          <a className="underline" href={entity.graphHref}>Open graph</a>
          {" · "}
          <a className="underline" href={entity.kindHref}>Back to {entity.kindLabel}</a>
        </p>
      </div>
    </>
  );
}