// A subnet's page: its leases, its reservations and its settings.
import { h, mount, badge, errorBox, confirmDialog, modal, input, debounce, readOnly, checkbox, select, field } from "../ui.js";
import { get, change, can } from "../api.js";
import { usageBar, subnetForm, fmtSeconds, subnetLabel, poolText, orderText } from "../widgets.js";
import { leasesTable } from "./leases.js";
import { reservationsTable, reservationDialog } from "./reservations.js";
import { rerender } from "../app.js";

const tabs = [["leases", "Leases"], ["reservations", "Reservations"], ["access", "Access"], ["settings", "Settings"]];

export async function render(el, params) {
  const id = params.id;
  const tab = params.tab || "leases";
  const s = await get("/subnets/" + id);
  const body = h("div");
  mount(el,
    h("nav", { class: "back-link" }, h("a", { href: "#/subnets" }, "← Subnets")),
    h("div", { class: "page-head" },
      h("div", { class: "grow" },
        h("h1", null, subnetLabel(s), " ", s.disabled ? badge("disabled", "off") : null),
        h("div", { class: "muted" }, "On ", h("span", { class: "mono" }, s.interface), " · pools ",
          s.pools.length ? h("span", { class: "mono" }, s.pools.map(poolText).join(", ")) : "none",
          orderText(s) ? " · " + orderText(s) : "",
          " · lease time ", s.lease_time ? fmtSeconds(s.lease_time) : "the default",
          s.access === "allow-list" ? [" · ", badge("allow-list", "accent")] : "")),
      h("div", { class: "subnet-usage" }, usageBar(s.usage)),
      can("config", true) ? h("div", { class: "actions" }, h("button", {
        title: s.disabled ? "Answer this subnet's clients again" : "Stop answering this subnet's clients; its configuration and leases stay",
        onclick: () => toggleSubnet(s) }, s.disabled ? "Enable subnet" : "Disable subnet")) : null),
    s.disabled ? h("div", { class: "msg warn" }, "This subnet is disabled: its clients get no answers. Its configuration and leases are kept.") : null,
    h("div", { class: "tabs" }, tabs.map(([k, label]) => h("a", { href: "#/subnets/" + id + "/" + k, class: tab === k ? "active" : "" }, label))),
    body);
  if (tab === "leases") await leasesTab(body, s);
  else if (tab === "reservations") await reservationsTab(body, s);
  else if (tab === "access") accessTab(body, s);
  else await settingsTab(body, s);
}

// matchList edits an allow or deny list: entries with a comment each.
function matchList(entries, placeholder) {
  const rows = h("div", { class: "pool-rows" });
  let list = [];
  const addRow = (m) => {
    const it = { match: input({ value: m ? m.match : "", placeholder, class: "mono" }), comment: input({ value: m ? m.comment || "" : "", placeholder: "what it is (optional)" }) };
    it.row = h("div", { class: "pool-row" }, it.match, it.comment,
      h("button", { type: "button", class: "small", title: "Remove", onclick: () => { it.row.remove(); list = list.filter((x) => x !== it); } }, "✕"));
    list.push(it);
    rows.append(it.row);
    return it.match;
  };
  for (const m of entries || []) addRow(m);
  const box = h("div", null, rows, h("button", { type: "button", class: "small", onclick: () => addRow(null).focus() }, "+ Add"));
  box.value = () => list.map((it) => ({ match: it.match.value.trim(), comment: it.comment.value.trim() })).filter((m) => m.match);
  return box;
}

// accessTab: who the subnet answers.
function accessTab(el, s) {
  const mode = select([["deny-list", "Deny-list: every client except those denied"], ["allow-list", "Allow-list: only clients allowed or with a reservation"]], s.access || "deny-list");
  const ph = "aa:bb:cc:dd:ee:ff, aa:bb:cc:* or id 01aabb…";
  const allow = matchList(s.allow, ph), deny = matchList(s.deny, ph);
  // The allow list only counts in an allow-list subnet.
  const sync = () => allow.classList.toggle("dimmed", mode.value !== "allow-list");
  mode.addEventListener("change", sync);
  const err = h("div");
  const save = async (dry) => {
    mount(err);
    try {
      const r = await change("PATCH", "/subnets/" + s.id, { access: mode.value, allow: allow.value(), deny: deny.value() }, { query: dry ? { dry_run: 1 } : undefined });
      if (!dry && r.applied) rerender();
    } catch (e) { mount(err, errorBox(e)); }
  };
  const form = h("div", { class: "form-grid" },
    field("Who gets an address", mode),
    field("Allow list", allow, "Used by an allow-list subnet. Clients with a reservation in the subnet are allowed too."),
    field("Deny list", deny, "Never answered, in either mode, even with a reservation."));
  const write = can("config", true);
  mount(el, h("div", { class: "panel" },
    h("p", { class: "muted" }, "Entries are a MAC address, a prefix for one maker's devices (aa:bb:cc:*) or a client identifier (id 01aabb…). A refused client gets no answer, and shows as DENIED in Activity; one with a lease gets a NAK when it next renews. Phones use a private MAC address per network unless told not to."),
    form, err,
    write ? h("div", { class: "actions", style: { marginTop: "14px" } },
      h("button", { class: "primary", onclick: () => save(false) }, "Save"),
      h("button", { onclick: () => save(true), title: "Check the change without saving it" }, "Check")) : null));
  if (!write) readOnly(el.querySelector(".panel"));
  sync();
}

export async function toggleSubnet(s) {
  if (!s.disabled && !await confirmDialog("Disable subnet", "Stop answering the clients of " + subnetLabel(s) + "? They keep their addresses until their leases run out, then have none. The configuration and leases stay; Enable brings it back.", "Disable", "danger")) return;
  try {
    await change("PATCH", "/subnets/" + s.id, { disabled: !s.disabled });
    rerender();
  } catch (e) { modal(s.disabled ? "Not enabled" : "Not disabled", errorBox(e)); }
}

async function leasesTab(el, s) {
  const search = input({ type: "search", placeholder: "address, MAC or host name" });
  const out = h("div");
  const toggle = checkbox("Include ended leases (expired and released)", false);
  toggle.input.addEventListener("change", () => draw());
  const draw = async () => {
    let ls = await get("/leases", { subnet: s.id, q: search.value.trim() });
    if (!toggle.input.checked) ls = ls.filter((l) => l.state === "active" || l.state === "declined");
    mount(out, leasesTable(ls, rerender, { subnet: true, empty: toggle.input.checked ? "No leases." : "No current leases." }));
  };
  search.addEventListener("input", debounce(draw, 300));
  mount(el, h("div", { class: "filter-row" }, search, toggle), h("div", { class: "panel" }, out));
  await draw();
}

async function reservationsTab(el, s) {
  const rs = await get("/reservations", { subnet: s.id });
  mount(el,
    can("config", true) ? h("div", { class: "filter-row" }, h("button", { class: "primary", onclick: () => reservationDialog(null, rerender) }, "New reservation")) : null,
    h("div", { class: "panel" }, reservationsTable(rs, rerender, { subnet: true, empty: "No reservations in this subnet." })));
}

async function settingsTab(el, s) {
  const settings = await get("/settings");
  const form = await subnetForm(s, settings);
  if (!can("config", true)) {
    mount(el, h("div", { class: "msg info" }, "You can see the subnet's settings but not change them (that needs config:write)."), readOnly(h("div", { class: "panel" }, form)));
    return;
  }
  const err = h("div");
  const save = async (dry) => {
    mount(err);
    try {
      const r = await change("PATCH", "/subnets/" + s.id, form.values(), { query: dry ? { dry_run: 1 } : undefined });
      if (!dry && r.applied) rerender();
    } catch (e) { mount(err, errorBox(e)); }
  };
  const del = async () => {
    const n = s.usage.reservations;
    if (!await confirmDialog("Delete subnet", "Delete " + subnetLabel(s) + (n ? " and its " + n + (n === 1 ? " reservation" : " reservations") : "") + "? Its clients get no answers from then on; their leases are kept until they run out. History can undo it.", "Delete", "danger")) return;
    try {
      await change("DELETE", "/subnets/" + s.id);
      location.hash = "#/subnets";
    } catch (e) { modal("Not deleted", errorBox(e)); }
  };
  mount(el, h("div", { class: "panel" }, form, err,
    h("div", { class: "actions", style: { marginTop: "14px" } },
      h("button", { class: "primary", onclick: () => save(false) }, "Save"),
      h("button", { onclick: () => save(true), title: "Check the change without saving it" }, "Check"),
      h("span", { class: "grow" }),
      h("button", { class: "danger", onclick: del }, "Delete subnet"))));
}