// Widgets shared by several pages: list editors with suggestions, the
// match editor of rules and NAT, descriptions, hit counts, durations.
import { h, input, select, field, checkbox } from "./ui.js";
import { get } from "./api.js";

// ---- durations

// fmtSeconds writes seconds the short way: 43200 is "12h", 5400 "1h30m".
export function fmtSeconds(n) {
  if (!n || n <= 0) return "";
  const parts = [];
  for (const [s, u] of [[86400, "d"], [3600, "h"], [60, "m"], [1, "s"]]) {
    if (n >= s) { parts.push(Math.floor(n / s) + u); n %= s; }
  }
  return parts.join("");
}

// parseSeconds reads "12h", "30m", "1d12h" or plain seconds; null when
// it can't.
export function parseSeconds(s) {
  s = String(s || "").trim();
  if (s === "") return 0;
  if (/^\d+$/.test(s)) return parseInt(s, 10);
  const re = /(\d+)\s*([dhms])/g;
  let total = 0, m, used = "";
  while ((m = re.exec(s))) {
    total += parseInt(m[1], 10) * { d: 86400, h: 3600, m: 60, s: 1 }[m[2]];
    used += m[0];
  }
  return used.replace(/\s/g, "") === s.replace(/\s/g, "") && total > 0 ? total : null;
}

// ---- names for suggestions

// names loads the zones, sets and services (with the built-in ones), for
// the editors' suggestions.
export async function names() {
  const [zones, sets, services] = await Promise.all([get("/zones"), get("/sets"), get("/services")]);
  return { zones: zones.map((z) => z.name), sets: sets.map((s) => s.name), services: services.map((s) => s.name), zoneList: zones, setList: sets };
}

let listID = 0;

// listEditor edits a list of strings, one per row, with suggestions.
// value() returns the non-empty entries.
export function listEditor(values, opts = {}) {
  const rows = h("div", { class: "list-rows" });
  const id = "dl" + (++listID);
  const datalist = h("datalist", { id }, (opts.suggestions || []).map((s) => h("option", { value: s })));
  let items = [];
  const add = (v) => {
    const it = { input: input({ value: v || "", placeholder: opts.placeholder || "", list: id, class: opts.mono === false ? "" : "mono" }) };
    it.row = h("div", { class: "list-row" }, it.input,
      h("button", { type: "button", class: "small", title: "Remove", onclick: () => { it.row.remove(); items = items.filter((x) => x !== it); } }, "✕"));
    items.push(it);
    rows.append(it.row);
    return it.input;
  };
  for (const v of values || []) add(v);
  const box = h("div", { class: "list-editor" }, rows, datalist,
    h("button", { type: "button", class: "small", onclick: () => add("").focus() }, "+ " + (opts.addLabel || "Add")));
  box.value = () => items.map((it) => it.input.value.trim()).filter((v) => v !== "");
  return box;
}

// ---- matches

// matchEditor edits what a rule, source NAT or redirect matches. It
// returns the form-grid fields; value() is the match's fields.
export function matchEditor(m, n, opts = {}) {
  m = m || {};
  const zones = (list) => listEditor(list, { suggestions: n.zones, placeholder: "zone", mono: false, addLabel: "Add zone" });
  const addrs = (list) => listEditor(list, { suggestions: n.sets, placeholder: "a set, 10.0.10.0/24, 2001:db8::/64, 10.0.0.1-10.0.0.9", addLabel: "Add" });
  const inZ = zones(m.in_zones), outZ = zones(m.out_zones);
  const notIn = checkbox("any zone but these", m.not_in), notOut = checkbox("any zone but these", m.not_out);
  const src = addrs(m.sources), dst = addrs(m.destinations);
  const notSrc = checkbox("any source but these", m.not_sources), notDst = checkbox("any destination but these", m.not_destinations);
  const svc = listEditor(m.services, { suggestions: n.services, placeholder: "ssh, https, tcp/8080, udp/1000-2000, icmp/echo-request", addLabel: "Add service" });
  const fam = select([["", "IPv4 and IPv6"], ["ipv4", "IPv4 only"], ["ipv6", "IPv6 only"]], m.family || "");
  const fields = [
    opts.in !== false ? field("Coming in on", h("div", null, inZ, notIn)) : null,
    opts.out !== false ? field("Going out on", h("div", null, outZ, notOut)) : null,
    field("From", h("div", null, src, notSrc), "Sets, addresses, prefixes or ranges, IPv4 and IPv6 mixed. Empty: any."),
    field("To", h("div", null, dst, notDst)),
    field("Services", svc, "Named services (built in, or yours) or entries such as tcp/8080. Empty: any traffic."),
    field("Family", fam),
  ];
  fields.value = () => {
    const v = { sources: src.value(), not_sources: notSrc.input.checked, destinations: dst.value(), not_destinations: notDst.input.checked,
      services: svc.value(), family: fam.value };
    if (opts.in !== false) Object.assign(v, { in_zones: inZ.value(), not_in: notIn.input.checked });
    if (opts.out !== false) Object.assign(v, { out_zones: outZ.value(), not_out: notOut.input.checked });
    return v;
  };
  return fields;
}

// describe sums up a match: "in lan · from trusted · ssh, dns".
export function describe(m) {
  const parts = [];
  const side = (word, not, list) => { if (list && list.length) parts.push(word + (not ? " not " : " ") + list.join(", ")); };
  side("in", m.not_in, m.in_zones);
  side("out", m.not_out, m.out_zones);
  side("from", m.not_sources, m.sources);
  side("to", m.not_destinations, m.destinations);
  if (m.services && m.services.length) parts.push(m.services.join(", "));
  if (m.family) parts.push(m.family + " only");
  return parts.length ? parts.join(" · ") : "everything";
}

// ---- hits

export function humanCount(n) {
  if (n >= 1e10) return Math.floor(n / 1e9) + "G";
  if (n >= 1e7) return Math.floor(n / 1e6) + "M";
  if (n >= 1e4) return Math.floor(n / 1e3) + "k";
  return String(n);
}

// hits shows an object's packets (marks add up), with bytes as a title.
export function hits(counters, ...marks) {
  let p = 0, b = 0, found = false;
  for (const m of marks) {
    const c = counters && counters[m];
    if (c) { p += c.packets; b += c.bytes; found = true; }
  }
  if (!found) return h("span", { class: "muted" }, "–");
  return h("span", { class: "mono", title: p + " packets, " + b + " bytes" }, humanCount(p));
}

// counters loads the hit counters ({} without log:read).
export async function counters() {
  try { return (await get("/counters")).counters; } catch { return {}; }
}