import Link from "next/link";
import type { Metadata } from "next";
import { PageShell, PageHeading } from "../components/PageShell";
import { Fact } from "../components/Fact";
import { loadSnapshot, formatBytes, SNAPSHOT_HREF } from "../lib/snapshot";

export const metadata: Metadata = {
  title: "Downloads",
  description:
    "Get the Archilyzer source as a dated snapshot tarball — MIT licensed, with a checksum.",
};

export default function DownloadsPage() {
  const snapshot = loadSnapshot();
  const date = snapshot
    ? new Date(snapshot.generatedAt).toLocaleDateString(undefined, {
        year: "numeric",
        month: "long",
        day: "numeric",
      })
    : null;

  return (
    <PageShell className="flex flex-col gap-10">
      <PageHeading
        eyebrow="Source"
        title="Downloads"
        standfirst="MIT licensed, published as a dated snapshot of the source tree."
      />

      <div className="doc-measure flex flex-col gap-4">
        <p className="leading-[1.7] text-[var(--muted-foreground)]">
          <strong className="font-semibold text-[var(--foreground)]">
            This is a snapshot, not a repository.
          </strong>{" "}
          A <code className="font-mono text-[var(--foreground)]">git archive</code>{" "}
          of the main branch — the working tree at one commit. No history, no
          branches, nothing to <code className="font-mono">git pull</code>.
          Updating means downloading a newer snapshot.
        </p>
        <p className="leading-[1.7] text-[var(--muted-foreground)]">
          The history is in the{" "}
          <Link
            href="/source/"
            className="underline decoration-[var(--border-strong)] underline-offset-2 hover:text-[var(--foreground)]"
          >
            read-only git mirror
          </Link>
          , published by the same build as this tarball.
        </p>
      </div>

      {snapshot ? (
        <div className="flex flex-col gap-6">
          <div>
            <a
              href={SNAPSHOT_HREF}
              className="inline-flex items-center gap-3 bg-[var(--foreground)] px-6 py-3.5 font-mono text-xs uppercase tracking-[0.16em] text-[var(--background)] rounded-[var(--radius)] hover:bg-[var(--brand)] hover:text-[var(--brand-ink)] transition-colors"
            >
              archilyzer-source.tar.gz
              <span className="tabular opacity-70">
                {formatBytes(snapshot.bytes)}
              </span>
            </a>
          </div>

          <div className="doc-measure flex flex-col">
            <Fact label="Snapshot of">{date}</Fact>
            <Fact label="Commit">
              <span className="tabular">{snapshot.commit}</span>
            </Fact>
            <Fact label="Subject">{snapshot.subject}</Fact>
            <Fact label="Size">
              <span className="tabular">
                {snapshot.bytes.toLocaleString()} bytes
              </span>
            </Fact>
            <Fact label="SHA-256">
              <span className="tabular">{snapshot.sha256}</span>
            </Fact>
          </div>

          <div className="doc-measure">
            <p className="mb-2 label-machine">Verify it</p>
            <pre className="p-4 rounded-[var(--radius)] bg-[var(--surface)] border border-[var(--border)] overflow-x-auto text-[0.8125rem] font-mono text-[var(--muted-foreground)]">
              {`sha256sum archilyzer-source.tar.gz\ntar xzf archilyzer-source.tar.gz\ncd archilyzer && pnpm install`}
            </pre>
          </div>
        </div>
      ) : (
        // No sidecar, or no tarball beside it: say so and render NO link. A
        // download button pointing at a file that isn't there is worse than an
        // honest absence.
        <div className="doc-measure faceplate p-5 flex flex-col gap-3">
          <p className="text-[var(--muted-foreground)] leading-relaxed">
            This build has no source snapshot attached.
          </p>
          <p className="text-sm text-[var(--faint)] leading-relaxed">
            The tarball and its sidecar are build artefacts, generated by{" "}
            <code className="font-mono">archilyzer source publish</code> (which{" "}
            <code className="font-mono">archilyzer build homepage</code> runs)
            and not committed. A site built without it ships no download, and
            says so here rather than linking to a file that isn&rsquo;t there.
          </p>
        </div>
      )}

      <div className="doc-measure flex flex-col gap-8 border-t border-[var(--border)] pt-8">
        <div className="flex flex-col gap-3">
          <h2 className="font-display text-base font-semibold text-[var(--foreground)]">
            What&rsquo;s inside
          </h2>
          <p className="text-sm leading-[1.7] text-[var(--muted-foreground)]">
            Every tracked file in the workspace: the editor, the static-site
            generator, the shared library, the MCP server, this site, the
            documentation, and the test suites. Enough to install, run, build and
            publish.
          </p>
        </div>

        <div className="flex flex-col gap-3">
          <h2 className="font-display text-base font-semibold text-[var(--foreground)]">
            What isn&rsquo;t
          </h2>
          <ul className="list-disc pl-5 space-y-2 text-sm leading-[1.7] text-[var(--muted-foreground)] marker:text-[var(--faint)]">
            <li>
              <strong className="text-[var(--foreground)]">
                The archive itself.
              </strong>{" "}
              No transcripts, no media, no index. The corpus lives outside the
              source tree by design, so it is structurally impossible for it to
              end up in here.
            </li>
            <li>
              <strong className="text-[var(--foreground)]">
                Any operator&rsquo;s configuration.
              </strong>{" "}
              The settings file is untracked; only a minimal example ships.
            </li>
            <li>
              <strong className="text-[var(--foreground)]">Dependencies.</strong>{" "}
              No <code className="font-mono">node_modules</code>. Run{" "}
              <code className="font-mono">pnpm install</code> after unpacking.
            </li>
            <li>
              <strong className="text-[var(--foreground)]">
                Models or binaries.
              </strong>{" "}
              yt-dlp, ffmpeg and a transcription backend are yours to install —
              see <Link href="/docs/install/" className="underline decoration-[var(--border-strong)] underline-offset-2 hover:text-[var(--foreground)]">Install</Link>.
            </li>
          </ul>
        </div>

        <div className="flex flex-col gap-3">
          <h2 className="font-display text-base font-semibold text-[var(--foreground)]">
            License
          </h2>
          <p className="text-sm leading-[1.7] text-[var(--muted-foreground)]">
            MIT. Use it, change it, run it, publish with it. The full text is in{" "}
            <code className="font-mono text-[var(--foreground)]">LICENSE</code>{" "}
            at the root of the archive.
          </p>
        </div>
      </div>
    </PageShell>
  );
}