// Leases: every address handed out, with filters; reserve or delete one.
import { h, mount, table, time, input, select, confirmDialog, toast, modal, errorBox, debounce, badge } from "../ui.js";
import { get, api, change, can } from "../api.js";
import { stateText, subnetLabel } from "../widgets.js";

// leaseHost is the host name to show: the reservation's, or what the
// client said.
function leaseHost(l) {
  if (l.reserved_hostname && l.hostname && l.reserved_hostname !== l.hostname) return [l.reserved_hostname, h("span", { class: "muted small" }, " (says " + l.hostname + ")")];
  return l.reserved_hostname || l.hostname || h("span", { class: "muted" }, "–");
}

// leasesTable shows leases with their actions; after a change, done() is
// called.
export function leasesTable(leases, done, opts = {}) {
  const write = can("leases", true), config = can("config", true);
  return table([
    { label: "Address", render: (l) => h("span", { class: "mono" }, l.ip) },
    { label: "MAC address", render: (l) => h("span", { class: "mono" }, l.mac || "–") },
    { label: "Host name", render: leaseHost },
    { label: "State", render: (l) => [stateBadge(l.state), l.reservation ? [" ", badge("reserved", "accent")] : null] },
    { label: "Ends", render: (l) => time(l.end) },
    opts.subnet ? null : { label: "Subnet", render: (l) => l.subnet || "–" },
    { label: "Interface", render: (l) => h("span", { class: "mono" }, l.interface) },
    { label: "", tdClass: "actions-cell", render: (l) => [
      config && !l.reservation && l.mac && l.state !== "declined" ? h("button", { class: "small reveal", title: "Give this client this address from now on", onclick: () => reserve(l, done) }, "Reserve") : null, " ",
      write ? h("button", { class: "small reveal", title: "Forget this lease: the address is free at once", onclick: () => del(l, done) }, "Delete") : null,
    ] },
  ].filter(Boolean), leases, { empty: opts.empty || "No leases." });
}

function stateBadge(st) {
  return badge(stateText(st), { active: "ok", declined: "warn" }[st] || "");
}

async function reserve(l, done) {
  const host = input({ value: l.hostname || "", placeholder: "host name (optional)" });
  const err = h("div");
  await modal("Reserve " + l.ip, h("div", null,
    h("p", null, l.mac + " keeps " + l.ip + " from now on."),
    h("div", { class: "form-grid" }, h("label", null, "Host name"), host), err), [
    { label: "Cancel", value: null },
    { label: "Reserve", kind: "primary", onclick: async () => {
      try {
        await change("POST", "/leases/" + l.ip + "/reserve", { hostname: host.value.trim() });
        done();
        return true;
      } catch (e) {
        mount(err, errorBox(e));
        return false;
      }
    } },
  ]);
}

async function del(l, done) {
  if (!await confirmDialog("Delete lease", "Forget the lease of " + l.ip + (l.mac ? " (" + l.mac + ")" : "") + "? The address is free at once; if the client still uses it, it gets a NAK when it next renews and asks for a new address.", "Delete", "danger")) return;
  try {
    await api("DELETE", "/leases/" + l.ip);
    toast("Deleted the lease of " + l.ip);
    done();
  } catch (e) { toast(e.message, "err", 8000); }
}

export async function render(el, params, query) {
  const subnets = await get("/subnets");
  const subnetSel = select([["", "all subnets"], ...subnets.map((s) => [String(s.id), subnetLabel(s)])], query.get("subnet") || "");
  const stateSel = select([["current", "active and held back"], ["active", "active"], ["expired", "expired"], ["released", "released"], ["declined", "held back"], ["", "all"]], query.get("state") || "current");
  const search = input({ type: "search", placeholder: "address, MAC or host name", value: query.get("q") || "" });
  const out = h("div");
  const draw = async () => {
    const st = stateSel.value === "current" ? "" : stateSel.value;
    let leases = await get("/leases", { subnet: subnetSel.value, state: st, q: search.value.trim() });
    if (stateSel.value === "current") leases = leases.filter((l) => l.state === "active" || l.state === "declined");
    const q = new URLSearchParams();
    if (subnetSel.value) q.set("subnet", subnetSel.value);
    if (stateSel.value !== "current") q.set("state", stateSel.value);
    if (search.value.trim()) q.set("q", search.value.trim());
    history.replaceState(null, "", "#/leases" + (q.toString() ? "?" + q : ""));
    mount(out, h("div", { class: "muted small" }, leases.length + (leases.length === 1 ? " lease" : " leases")), leasesTable(leases, draw));
  };
  subnetSel.addEventListener("change", draw);
  stateSel.addEventListener("change", draw);
  search.addEventListener("input", debounce(draw, 300));
  mount(el,
    h("div", { class: "page-head" }, h("div", { class: "grow" }, h("h1", null, "Leases"),
      h("div", { class: "muted" }, "Addresses handed out. Expired and released leases are kept a while, so a client that comes back gets its old address."))),
    h("div", { class: "filter-row" }, subnetSel, stateSel, search, h("button", { onclick: draw }, "Refresh")),
    h("div", { class: "panel" }, out));
  await draw();
}