import type { RadioChannel } from "@/lib/types";

// node-26#24. A node on a conventional system reports each channel it
// decodes and whether the agency encrypts it — the one decode failure nothing
// on the node can fix, so it has to be said plainly here.
const ALGIDS: Record<number, string> = {
  0x81: "DES-OFB", 0x83: "Triple DES", 0x84: "AES-256", 0x85: "AES-128",
  0x9f: "DES-XL", 0xa0: "DVI-XL", 0xa1: "DVP-XL", 0xaa: "ADP (RC4)",
};

function mhz(hz: number | null): string {
  return hz ? `${(hz / 1e6).toFixed(4)} MHz` : "";
}

function hex(n: number, width: number): string {
  return n.toString(16).toUpperCase().padStart(width, "0");
}

export function RadioChannels({ channels }: { channels?: RadioChannel[] | null }) {
  if (!channels || channels.length === 0) return null;
  const encrypted = channels.filter((c) => c.encrypted);
  // "Reassign the node" only when nothing in the clear has ever been heard on
  // any channel — `encrypted` alone means the most recent call was.
  const all = encrypted.length === channels.length && channels.every((c) => c.clear_calls === 0);
  const subject = all
    ? channels.length === 1 ? "This channel is" : "Every channel is"
    : `${encrypted.length} of ${channels.length} channels ${encrypted.length === 1 ? "is" : "are"} now`;
  return (
    <section>
      <h2 className="text-sm font-semibold text-gray-400 uppercase tracking-wider mb-3">Conventional Channels</h2>
      {encrypted.length > 0 && (
        <p role="status" className="text-xs text-red-300 bg-red-950 border border-red-900 rounded-lg px-3 py-2 mb-3 font-mono">
          {subject} encrypted — those calls can&apos;t be decoded, so nothing from{" "}
          {encrypted.length === 1 ? "it" : "them"} is recorded. Nothing to fix on the node
          {all ? "; assign this node a different system." : "; clear calls are still recorded."}
        </p>
      )}
      <ul className="space-y-1 font-mono text-xs">
        {channels.map((c, i) => (
          <li key={i} className="flex flex-wrap gap-x-3 text-gray-300">
            <span className="text-white">{c.name || mhz(c.freq)}</span>
            {c.name && <span className="text-gray-500">{mhz(c.freq)}</span>}
            {c.nac != null && <span className="text-gray-500">NAC {hex(c.nac, 3)}</span>}
            {c.encrypted ? (
              <span className="text-red-400">
                ✕ Encrypted{c.algid != null ? ` · ${ALGIDS[c.algid] ?? `ALGID ${hex(c.algid, 2)}`}` : ""}
                {c.keyid != null ? ` · key ${hex(c.keyid, 4)}` : ""}
              </span>
            ) : (
              <span className="text-gray-400">
                {c.clear_calls > 0 ? `Clear · ${c.clear_calls} calls heard` : "No traffic heard yet"}
              </span>
            )}
          </li>
        ))}
      </ul>
    </section>
  );
}