// The zone page's DNSSEC tab: the zone's signing status, its DS record for
// the parent zone, and the steps to turn signing on and off. Every step
// that can affect resolvers opens a dialog that says what must be done
// first (docs/dnssec.md).
import { h, mount, table, badge, modal, toast, errorBox, display, input, select, checkbox, copyBox, fmtTime } from "../ui.js";
import { api, get, change, describeResult, state } from "../api.js";
import { rerender } from "../app.js";
import { publishDS } from "./registrar.js";

const phaseBadge = {
  off: ["off", ""], leftover_keys: ["off · old keys", "warn"], starting: ["starting", "accent"],
  signing: ["signing", "accent"], ready: ["ready for DS", "warn"], ds_pending: ["DS added", "accent"],
  secure: ["secure", "ok"], removing_ds: ["turning off: remove DS", "warn"], ds_expiring: ["turning off", "accent"],
  removing_keys: ["turning off", "accent"], unsigned: ["turning off: finished", "ok"],
};

export async function dnssecTab(el, zone) {
  const [s, zones] = await Promise.all([get("/zones/" + zone.id + "/dnssec"), get("/zones").catch(() => [])]);
  const admin = state.me && state.me.admin;
  const others = zones.filter((z) => z.name === zone.name && z.id !== zone.id);
  const ph = s.phase;
  const [btext, bkind] = phaseBadge[ph.code] || [ph.code, ""];
  const signing = s.policy && s.policy !== "insecure";
  const out = h("div");

  const buttons = [];
  if (!s.policy) buttons.push(h("button", { class: "primary", onclick: () => enableDialog(zone, s, others) }, "Turn signing on…"));
  if (s.policy) buttons.push(h("button", { onclick: () => checkDS(zone, out) }, "Check DS at parent"));
  if (signing) buttons.push(h("button", { onclick: () => disableDialog(zone, s) }, "Turn signing off…"));
  if (s.policy === "insecure") buttons.push(h("button", { class: ph.can_finish ? "primary" : "", disabled: !ph.can_finish, title: ph.can_finish ? "" : "Not yet: " + (ph.next || ph.summary), onclick: () => finishDialog(zone) }, "Finish turning off"));
  if (admin && (s.policy || s.keys.length)) buttons.push(h("button", { class: "danger", onclick: () => wipeDialog(zone, s) }, "Wipe (clean slate)…"));

  const parts = [h("div", { class: "panel" },
    h("div", { class: "page-head" },
      h("h2", { class: "grow" }, "DNSSEC signing ", badge(btext, bkind)),
      h("div", { class: "actions" }, buttons)),
    h("p", null, ph.summary),
    ph.next ? h("div", { class: "msg " + (ph.code === "removing_ds" || ph.code === "ready" ? "warn" : "info") }, h("strong", null, "Next: "), ph.next) : null,
    s.policy ? h("dl", { class: "kv small" },
      h("dt", null, "Policy"), h("dd", { class: "mono" }, s.policy === "insecure" ? "insecure (turning off)" : s.policy),
      s.named && s.named.secure ? [h("dt", null, "Signed serial"), h("dd", { class: "mono" }, s.named.signed_serial + " (zone file " + s.named.serial + ")")] : null,
      s.named && s.named.next_key_event ? [h("dt", null, "Next key event"), h("dd", null, s.named.next_key_event)] : null,
      h("dt", null, "Key directory"), h("dd", { class: "mono" }, s.key_dir)) : null,
    s.named_error ? h("div", { class: "msg warn small" }, "named: " + s.named_error) : null,
    s.key_error ? h("div", { class: "msg err small" }, "The keys can't be read: " + s.key_error) : null,
    !s.policy && !s.keys.length ? h("p", { class: "muted small" },
      "Signing lets resolvers that validate DNSSEC detect forged answers for the zone. It only matters for a zone on the internet: validation needs a DS record in the parent zone (at your registrar), and resolvers on your own network don't validate zones this server answers itself.") : null,
    out)];

  const live = s.keys.filter((k) => k.ds && k.goal === "omnipresent");
  if (live.length && s.policy !== "insecure") parts.push(dsPanel(zone, s, live));
  if (s.keys.length) {
    parts.push(h("div", { class: "panel" },
      h("h2", null, "Keys"),
      table([
        { label: "Tag", render: (k) => k.tag, tdClass: "mono" },
        { label: "Role", render: (k) => k.role },
        { label: "Algorithm", render: (k) => k.algorithm_name || k.algorithm, tdClass: "small" },
        { label: "Goal", render: (k) => stateBadge(k.goal) },
        { label: "DNSKEY", render: (k) => stateBadge(k.dnskey_state) },
        { label: "DS at parent", render: (k) => stateBadge(k.ds_state) },
        { label: "Created", render: (k) => k.created ? fmtTime(k.created) : "–", tdClass: "small" },
      ], s.keys),
      h("p", { class: "muted small" }, "States are named's: rumoured = published, but caches may not have it yet; omnipresent = everyone has it; unretentive = removed, but caches may still have it; hidden = gone.")));
  }
  mount(el, parts);
}

function stateBadge(st) {
  if (!st) return h("span", { class: "muted" }, "–");
  return badge(st, { omnipresent: "ok", rumoured: "accent", unretentive: "warn" }[st] || "");
}

function dsPanel(zone, s, keys) {
  const ph = s.phase;
  const where = s.parent_zone
    ? ["The parent zone ", h("a", { href: "#/zones" }, display(s.parent_zone)), " is in Jarl: add this as a DS record there (name ", h("code", null, display(zone.name)), ")."]
    : "Give this to your registrar (at Porkbun: the domain's DNSSEC settings). Registrars ask either for the whole record or for its four fields.";
  return h("div", { class: "panel" },
    h("h2", null, "DS record for the parent zone"),
    ph.can_publish_ds
      ? h("div", { class: "msg ok" }, ph.code === "secure" ? "The parent has this DS record." : "Ready: the DS record can be added at the parent now. Then click Check DS at parent.")
      : h("div", { class: "msg warn" }, h("strong", null, "Not yet. "),
        ph.ds_ready_at ? "Wait until " + fmtTime(ph.ds_ready_at) + "." : "Wait until named says the zone is ready.",
        " Adding the DS earlier can make the zone fail to validate for resolvers that still have unsigned answers cached."),
    h("p", { class: "small" }, where),
    s.registrar && state.me && state.me.admin && ph.code !== "secure" && ph.code !== "ds_pending"
      ? h("p", null, h("button", { class: ph.can_publish_ds ? "primary" : "", onclick: () => publishDS(zone) }, "Publish at Porkbun…"),
        h("span", { class: "muted small" }, " Jarl checks that it's safe first; the Registrar tab shows everything at Porkbun.")) : null,
    keys.map((k) => h("div", { class: "ds-record" },
      h("label", { class: "small muted" }, "Key " + k.tag + " — DS record"),
      copyBox(k.ds.record.replace(/\t/g, " ")),
      h("dl", { class: "kv small" },
        h("dt", null, "Key tag"), h("dd", null, copyBox(String(k.ds.key_tag))),
        h("dt", null, "Algorithm"), h("dd", null, copyBox(String(k.ds.algorithm)), h("span", { class: "muted" }, " " + (k.algorithm_name || ""))),
        h("dt", null, "Digest type"), h("dd", null, copyBox(String(k.ds.digest_type)), h("span", { class: "muted" }, " SHA-256")),
        h("dt", null, "Digest"), h("dd", null, copyBox(k.ds.digest))))));
}

async function apply(zone, policy) {
  const r = await change("PATCH", "/zones/" + zone.id, { dnssec_policy: policy }, { immediate: true });
  toast(describeResult(r));
  rerender();
}

function steps(items) {
  return h("ol", { class: "small" }, items.map((i) => h("li", null, i)));
}

async function enableDialog(zone, s, others) {
  const pol = select(s.policies.map((p) => [p, p === "default" ? "default (BIND's built-in policy)" : p]), "default");
  const err = h("div");
  const split = others.length ? h("div", { class: "msg warn small" },
    "This signs the zone in view ", h("strong", null, zone.view || "default"), " only; ",
    others.map((o) => display(o.name) + " in view " + o.view).join(", "),
    " stays unsigned. That's the usual split-DNS setup. Once the DS record is at the parent, a device that validates DNSSEC itself (a Pi-hole or Unbound with DNSSEC on, systemd-resolved with DNSSEC=yes) and gets the unsigned copy rejects it; resolvers asking this server directly are fine, because BIND doesn't validate zones it serves itself.") : null;
  await modal("Turn signing on for " + zone.display_name, [
    h("p", null, "named creates a key and signs the zone: Jarl keeps writing the zone as before, and named keeps a signed copy next to it. ",
      h("strong", null, "Nothing changes for resolvers yet"), ": they only start validating once the zone's DS record is added at the parent zone, which this page tells you when to do."),
    h("p", { class: "small" }, "Before you start:"),
    steps([
      "The server's clock must be right (NTP): signatures are valid for a fixed time window.",
      "TTLs in the zone must be at most a day; Jarl refuses longer ones.",
      "Secondaries get the signed zone by zone transfer; they need nothing else.",
      "With the default policy the key is never replaced, so the DS at your registrar never has to change. Keep backups: the daily backup includes the keys.",
    ]),
    split,
    s.policies.length > 1 ? h("div", { class: "form-grid" }, h("label", null, "Policy"), pol) : null,
    err,
  ], [
    { label: "Cancel", value: null },
    { label: "Turn signing on", kind: "primary", onclick: async () => {
      try { await apply(zone, pol.value); } catch (e) { mount(err, errorBox(e)); return false; }
    } },
  ], { wide: true });
}

async function disableDialog(zone, s) {
  const err = h("div");
  const hadDS = s.keys.some((k) => k.ds_published || k.ds_state === "omnipresent");
  await modal("Turn signing off for " + zone.display_name, [
    h("p", null, "Signing is turned off in steps, so the zone is never unsigned while the parent zone still has its DS record (validating resolvers would then reject the whole domain):"),
    steps([
      [h("strong", null, "Now: "), "the zone switches to BIND's insecure policy. named keeps it signed and publishes a CDS \"delete\" record. Nothing breaks."],
      [h("strong", null, "You: "), "remove the DS record at your registrar (", s.registrar ? "the Registrar tab can do that at Porkbun" : "at Porkbun: the domain's DNSSEC settings", "), then click Check DS at parent so named knows it's gone."],
      [h("strong", null, "named: "), "waits until resolvers have forgotten the DS (the parent's DS TTL, often a day), then removes the keys and signatures."],
      [h("strong", null, "Then: "), "this page lets you finish, which switches DNSSEC off."],
    ]),
    hadDS ? null : h("p", { class: "muted small" }, "named has never seen a DS for this zone at its parent, so this will go quickly. If you're sure the parent never had one, Wipe switches off at once."),
    err,
  ], [
    { label: "Cancel", value: null },
    { label: "Start turning off", kind: "primary", onclick: async () => {
      try { await apply(zone, "insecure"); } catch (e) { mount(err, errorBox(e)); return false; }
    } },
  ], { wide: true });
}

async function finishDialog(zone) {
  const err = h("div");
  await modal("Finish turning signing off", [
    h("p", null, "The parent zone has no DS record for ", h("strong", null, zone.display_name), " any more, and named has stopped counting on it. Switching DNSSEC off now is safe: named serves the zone unsigned."),
    h("p", { class: "muted small" }, "The old keys stay in the key directory (named keeps them retired); Wipe deletes them."),
    err,
  ], [
    { label: "Cancel", value: null },
    { label: "Switch DNSSEC off", kind: "primary", onclick: async () => {
      try { await apply(zone, ""); } catch (e) { mount(err, errorBox(e)); return false; }
    } },
  ]);
}

async function wipeDialog(zone, s) {
  const err = h("div");
  const confirmName = input({ placeholder: zone.display_name, class: "mono", autocomplete: "off" });
  const force = checkbox("The parent can't be checked from here, and I'm sure it has no DS record for this zone (for example, the zone isn't on the internet)", false);
  await modal("Wipe DNSSEC from " + zone.display_name, [
    h("div", { class: "msg err" },
      h("strong", null, "This can take the domain offline. "),
      "Wipe switches signing off at once and deletes the zone's keys and named's signed copy. If the parent zone still has a DS record for the zone, or resolvers still have one cached, every validating resolver rejects the whole domain until it's gone and its TTL has passed (often a day). The deleted keys can't be brought back except from a backup."),
    h("p", null, "Jarl asks the parent zone's servers first and refuses while they have a DS record. Use Turn signing off instead if the zone is on the internet and ever had a DS."),
    s.policy ? null : h("p", { class: "small" }, "Signing is already off; this deletes the old keys left in the key directory."),
    h("div", { class: "form-grid" }, h("label", null, "Type the zone name to confirm"), confirmName),
    force,
    err,
  ], [
    { label: "Cancel", value: null },
    { label: "Wipe", kind: "danger", onclick: async () => {
      if (confirmName.value.trim().replace(/\.$/, "").toLowerCase() !== zone.display_name.toLowerCase()) {
        mount(err, h("div", { class: "msg err" }, "Type the zone name to confirm."));
        return false;
      }
      try {
        const r = await api("POST", "/zones/" + zone.id + "/dnssec/wipe", { body: { force: force.input.checked } });
        toast("Wiped: " + r.removed.length + " files removed");
        rerender();
      } catch (e) { mount(err, errorBox(e)); return false; }
    } },
  ], { wide: true, sticky: true });
}

async function checkDS(zone, out) {
  mount(out, h("div", { class: "muted" }, "Asking the parent zone's servers…"));
  try {
    const r = await api("POST", "/zones/" + zone.id + "/dnssec/check-ds");
    const p = r.parent;
    mount(out, h("div", { class: "msg " + (p.error ? "err" : "info") },
      p.error ? p.error : [
        "Parent zone ", h("strong", { class: "mono" }, display(p.parent)), " (" + p.reached + " of " + p.parent_servers.length + " servers answered): ",
        p.delegated ? (p.ds.length ? "DS record" + (p.ds.length > 1 ? "s" : "") + " for key " + p.ds.map((d) => d.key_tag).join(", ") : "no DS record") : "the zone isn't delegated",
        "."],
      r.marked.map((m) => h("div", null, "named told: " + m)),
      r.notes.map((n) => h("div", { class: "small" }, n))));
    if (r.marked.length) setTimeout(rerender, 1500);
  } catch (e) { mount(out, errorBox(e)); }
}