import Link from "next/link";
import { listDocuments, listSections } from "@mcpedia/core";

export const dynamic = "force-dynamic";

export default async function DashboardPage() {
  const [all, sections] = await Promise.all([listDocuments(), listSections()]);

  const totalTags = new Set(all.flatMap((d) => d.tags)).size;
  const recentDocs = [...all].sort((a, b) => new Date(b.updatedAt).getTime() - new Date(a.updatedAt).getTime()).slice(0, 8);

  // Tag aggregation server-side for SSR snapshot (client TagCloud will hydrate live via SWR)
  const tagCounts = new Map<string, number>();
  for (const d of all) for (const t of d.tags) tagCounts.set(t, (tagCounts.get(t) ?? 0) + 1);
  const topTags = [...tagCounts.entries()].sort((a, b) => b[1] - a[1]).slice(0, 12);

  return (
    <div className="space-y-8 max-w-5xl">
      <div className="flex items-center justify-between">
        <div>
          <h1 className="text-2xl sm:text-3xl font-extrabold text-[var(--text-primary)] tracking-tight">Dashboard</h1>
          <p className="text-xs sm:text-sm text-[var(--text-muted)] mt-1">Live overview of the MCPedia knowledge base. Data via PostgreSQL Core + BullMQ queue.</p>
        </div>
        <Link href="/create" className="hidden sm:inline-flex items-center gap-1.5 px-3 py-1.5 bg-[var(--brand)] text-[var(--brand-fg)] rounded-md text-xs font-semibold shadow-xs">
          + New Doc
        </Link>
      </div>

      {/* Metric strip — SSR snapshot */}
      <div className="grid grid-cols-2 lg:grid-cols-4 gap-3">
        <div className="p-4 bg-[var(--bg-surface)] border border-[var(--border-color)] rounded-xl shadow-xs">
          <div className="text-[10px] font-mono uppercase tracking-wider text-[var(--text-muted)]">DB Documents</div>
          <div className="text-2xl font-bold font-mono text-[var(--text-primary)] mt-1">{all.length}</div>
          <div className="text-[11px] text-[var(--text-dim)] font-mono">{totalTags} unique tags</div>
        </div>
        <div className="p-4 bg-[var(--bg-surface)] border border-[var(--border-color)] rounded-xl shadow-xs">
          <div className="text-[10px] font-mono uppercase tracking-wider text-[var(--text-muted)]">Active Sections</div>
          <div className="text-2xl font-bold font-mono text-[var(--text-primary)] mt-1">{sections.length}</div>
          <div className="text-[11px] text-[var(--text-dim)] font-mono truncate">{sections.map((s) => s.id).join(" · ")}</div>
        </div>
        <div className="p-4 bg-[var(--bg-surface)] border border-[var(--border-color)] rounded-xl shadow-xs">
          <div className="text-[10px] font-mono uppercase tracking-wider text-[var(--text-muted)]">Search</div>
          <div className="text-2xl font-bold font-mono text-[var(--text-primary)] mt-1">RRF</div>
          <div className="text-[11px] text-[var(--text-dim)] font-mono">FTS + Cosine Vectors</div>
        </div>
        <div className="p-4 bg-[var(--bg-surface)] border border-[var(--border-color)] rounded-xl shadow-xs">
          <div className="text-[10px] font-mono uppercase tracking-wider text-[var(--text-muted)]">MCP Tools</div>
          <div className="text-2xl font-bold font-mono text-[var(--text-primary)] mt-1">13</div>
          <div className="text-[11px] text-[var(--text-dim)] font-mono">HTTP :4021</div>
        </div>
      </div>

      {/* Queue strip — client component polls live */}
      <DashboardQueueStrip />

      {/* Section breakdown */}
      <section className="bg-[var(--bg-surface)] border border-[var(--border-color)] rounded-xl p-5 shadow-xs">
        <h2 className="text-xs font-bold uppercase tracking-wider text-[var(--text-muted)] font-mono mb-3">Section Breakdown</h2>
        <div className="space-y-2">
          {sections.map((s) => {
            const pct = all.length ? Math.round((s.docCount / all.length) * 100) : 0;
            return (
              <Link key={s.id} href={`/${s.id}`} className="flex items-center gap-3 group">
                <span className="text-sm w-6 text-center">{s.icon}</span>
                <span className="text-xs font-semibold text-[var(--text-primary)] group-hover:underline w-28 truncate">{s.label}</span>
                <div className="flex-1 h-2 bg-[var(--bg-elevated)] rounded-full overflow-hidden border border-[var(--border-color)]">
                  <div className="h-full bg-[var(--brand)] rounded-full transition-all" style={{ width: `${pct}%` }} />
                </div>
                <span className="text-[11px] font-mono text-[var(--text-muted)] w-14 text-right">{s.docCount} docs · {pct}%</span>
              </Link>
            );
          })}
        </div>
      </section>

      {/* Top tags */}
      {topTags.length > 0 && (
        <section className="bg-[var(--bg-surface)] border border-[var(--border-color)] rounded-xl p-5 shadow-xs">
          <h2 className="text-xs font-bold uppercase tracking-wider text-[var(--text-muted)] font-mono mb-3">Top Tags</h2>
          <div className="flex flex-wrap gap-1.5">
            {topTags.map(([tag, count]) => (
              <Link key={tag} href={`/search?q=${encodeURIComponent(tag)}`} className="px-2.5 py-1 rounded-full bg-[var(--bg-elevated)] border border-[var(--border-color)] text-xs font-mono text-[var(--text-secondary)] hover:text-[var(--text-primary)] hover:border-[var(--text-muted)]">
                #{tag} <span className="text-[10px] bg-[var(--bg-surface)] px-1 py-0.2 rounded ml-1">{count}</span>
              </Link>
            ))}
          </div>
          <div className="mt-3">
            <TagCloudClient />
          </div>
        </section>
      )}

      {/* Recent */}
      {recentDocs.length > 0 && (
        <section>
          <h2 className="text-xs font-bold uppercase tracking-wider text-[var(--text-muted)] font-mono mb-3">Recently Updated</h2>
          <div className="grid grid-cols-1 sm:grid-cols-2 gap-3">
            {recentDocs.map((d) => (
              <Link key={d.slug} href={`/${d.slug}`} className="p-4 bg-[var(--bg-surface)] border border-[var(--border-color)] hover:border-[var(--text-muted)] rounded-xl shadow-xs group">
                <div className="text-[10px] font-mono uppercase text-[var(--text-muted)]">{d.section} · {new Date(d.updatedAt).toLocaleDateString()}</div>
                <div className="text-sm font-semibold text-[var(--text-primary)] group-hover:underline line-clamp-1 mt-1">{d.title}</div>
                {d.tags.length > 0 && <div className="flex gap-1 mt-2 flex-wrap">{d.tags.slice(0, 3).map((t) => <span key={t} className="text-[10px] px-1.5 py-0.2 bg-[var(--bg-elevated)] border border-[var(--border-color)] rounded font-mono text-[var(--text-muted)]">#{t}</span>)}</div>}
              </Link>
            ))}
          </div>
        </section>
      )}
    </div>
  );
}

// Client islands — isolated so the page stays RSC
import DashboardQueueStrip from "./QueueStrip";
import TagCloudClient from "./TagCloudClient";