// Jarl web UI: router, layout and login.
import { h, mount, toast, errorBox, plural, lastList, modal } from "./ui.js";
import { wordmark, logo } from "./brand.js";
import { api, get, state, loadDraft, onChange, setUnauthorizedHandler, setImmediate, setCodePrompt, useDraft } from "./api.js";
import * as totp from "./totp.js";
import * as dashboard from "./pages/dashboard.js";
import * as zones from "./pages/zones.js";
import * as zone from "./pages/zone.js";
import * as views from "./pages/views.js";
import * as acls from "./pages/acls.js";
import * as keys from "./pages/keys.js";
import * as options from "./pages/options.js";
import * as changes from "./pages/changes.js";
import * as history from "./pages/history.js";
import * as audit from "./pages/audit.js";
import * as users from "./pages/users.js";
import * as account from "./pages/account.js";
import * as search from "./pages/search.js";
import * as stats from "./pages/stats.js";
import * as blocking from "./pages/blocking.js";
import * as exposure from "./pages/exposure.js";

const routes = [
  { pattern: /^$/, page: dashboard, nav: "dashboard" },
  { pattern: /^zones$/, page: zones, nav: "zones" },
  { pattern: /^zones\/(\d+)(?:\/(\w+))?$/, page: zone, nav: "zones", params: ["id", "tab"] },
  { pattern: /^views$/, page: views, nav: "views" },
  { pattern: /^views\/(\d+)(?:\/(\w+))?$/, page: views, nav: "views", params: ["id", "tab"] },
  { pattern: /^acls$/, page: acls, nav: "acls" },
  { pattern: /^keys$/, page: keys, nav: "keys" },
  { pattern: /^options$/, page: options, nav: "options" },
  { pattern: /^changes$/, page: changes, nav: "changes" },
  { pattern: /^history$/, page: history, nav: "history" },
  { pattern: /^history\/(\d+)$/, page: history, nav: "history", params: ["id"] },
  { pattern: /^audit$/, page: audit, nav: "audit" },
  { pattern: /^users$/, page: users, nav: "users" },
  { pattern: /^account$/, page: account, nav: "account" },
  { pattern: /^search$/, page: search, nav: "" },
  { pattern: /^stats$/, page: stats, nav: "stats" },
  { pattern: /^blocking$/, page: blocking, nav: "blocking" },
  { pattern: /^exposure$/, page: exposure, nav: "exposure" },
];

const navItems = [
  ["dashboard", "#/", "Dashboard"],
  ["stats", "#/stats", "Statistics"],
  ["zones", "#/zones", "Zones"],
  ["blocking", "#/blocking", "Blocking"],
  ["views", "#/views", "Views"],
  ["exposure", "#/exposure", "Exposure"],
  ["acls", "#/acls", "ACLs"],
  ["keys", "#/keys", "TSIG keys"],
  ["options", "#/options", "Server options"],
  ["changes", "#/changes", "Changes"],
  ["history", "#/history", "History"],
  ["audit", "#/audit", "Audit log"],
];

const app = document.getElementById("app");
let mainEl, navEl, barEl, current = { key: "" }, routeGen = 0;

function parseHash() {
  const raw = location.hash.replace(/^#\/?/, "");
  const [path, qs] = raw.split("?");
  return { path: path.replace(/\/$/, ""), query: new URLSearchParams(qs || "") };
}

function renderLogin(message) {
  const user = h("input", { name: "username", autocomplete: "username", placeholder: "Username", required: true });
  const pass = h("input", { name: "password", type: "password", autocomplete: "current-password", placeholder: "Password", required: true });
  const err = h("div");
  const form = h("form", { onsubmit: async (e) => {
    e.preventDefault();
    mount(err);
    try {
      const r = await api("POST", "/auth/login", { body: { username: user.value, password: pass.value } });
      if (r.totp_required) { renderCodeStep(r.challenge); return; }
      await loggedIn(r);
    } catch (ex) {
      mount(err, errorBox(ex));
      pass.select();
    }
  } }, user, pass, h("button", { class: "primary", type: "submit" }, "Log in"), err);
  mount(app, loginPanel(message, form));
  user.focus();
}

function loginPanel(message, ...body) {
  return h("div", { class: "login panel" },
    logo(104, "login-logo"),
    h("h1", null, wordmark()),
    h("div", { class: "tag" }, "Rule your DNS holds"),
    message ? h("div", { class: "msg warn" }, message) : null,
    ...body);
}

// renderCodeStep is the second login step for users with two-factor login.
function renderCodeStep(challenge) {
  const code = h("input", { name: "code", autocomplete: "one-time-code", inputmode: "numeric", placeholder: "6-digit code", required: true, class: "totp-code" });
  const err = h("div");
  let recovery = false;
  const hint = h("div", { class: "small muted" });
  const toggle = h("a", { href: "#", class: "small", onclick: (e) => {
    e.preventDefault();
    recovery = !recovery;
    code.placeholder = recovery ? "Recovery code, e.g. k7dm2-xq9pw" : "6-digit code";
    code.inputMode = recovery ? "text" : "numeric";
    toggle.textContent = recovery ? "Use the authenticator app" : "Lost your phone? Use a recovery code";
    code.value = "";
    code.focus();
  } }, "Lost your phone? Use a recovery code");
  mount(hint, "Enter the code from your authenticator app.");
  const form = h("form", { onsubmit: async (e) => {
    e.preventDefault();
    mount(err);
    try {
      const me = await api("POST", "/auth/login/totp", { body: { challenge, code: code.value } });
      await loggedIn(me);
    } catch (ex) {
      if (ex.code === "login_expired") { renderLogin(ex.message); return; }
      mount(err, errorBox(ex));
      code.select();
    }
  } }, hint, code, h("button", { class: "primary", type: "submit" }, "Verify"), toggle, err);
  mount(app, loginPanel(null, form));
  code.focus();
}

async function loggedIn(me) {
  state.me = me;
  state.csrf = me.csrf_token || "";
  if (me.totp_setup_required) renderSetupRequired();
  else await start();
}

// renderSetupRequired: the server requires two-factor login for this
// user (totp.require), and it isn't set up yet. Nothing else works until
// it is.
function renderSetupRequired() {
  const box = h("div");
  mount(app, h("div", { class: "login panel wide" },
    logo(64, "login-logo"),
    h("h1", null, "Set up two-factor login"),
    h("p", null, "This server requires two-factor login for your account. Set up an authenticator app to continue."),
    box,
    h("div", { class: "small", style: { marginTop: "12px" } }, h("a", { href: "#", onclick: (e) => { e.preventDefault(); logout(); } }, "Log out"))));
  totp.setup(box, state.me, async () => {
    const me = await get("/auth/whoami");
    await loggedIn(me);
  });
}

function layout() {
  navEl = h("nav", { class: "main" });
  let modeEl;
  barEl = h("div");
  mainEl = h("main");
  const q = h("input", { type: "search", placeholder: "Search names, data…", "aria-label": "Search" });
  const me = state.me;
  const header = h("header", { class: "top" },
    h("a", { class: "brand", href: "#/", title: "Dashboard" },
      logo(30),
      wordmark({ rule: false, height: 19, cls: "brand-name" })),
    navEl,
    h("div", { class: "spacer" }),
    modeEl = h("span"),
    h("form", { class: "search", onsubmit: (e) => { e.preventDefault(); if (q.value.trim()) location.hash = "#/search?q=" + encodeURIComponent(q.value.trim()); } }, q),
    h("a", { href: "#/account", class: "user", title: (me.permissions || []).join("\n") }, me.user.username),
    me.admin ? h("a", { href: "#/users" }, "Users") : null,
    h("button", { class: "small", onclick: logout }, "Log out"));
  mount(app, h("div", { class: "shell" }, header, barEl, mainEl, footer(me.build)));
  modeHolder = modeEl;
  renderNav();
  renderBar();
}

let modeHolder;

// footer names the Jarl build: the release, or the commit for other
// builds, linked to it in the repository.
function footer(b) {
  if (!b) return null;
  let title = b.tag ? "Jarl " + b.version + " (release " + b.tag + ")" : "Jarl " + b.version + " (built without git)";
  if (!b.tag && b.commit) {
    title = "Development build of commit " + b.commit + (b.modified ? " with uncommitted changes" : "");
    if (b.since) title += b.ahead ? ", " + b.ahead + (b.ahead === 1 ? " commit" : " commits") + " after " + b.since : ", at " + b.since;
  }
  return h("footer", { class: "site" }, "Powered by ",
    h("a", { href: b.url, target: "_blank", rel: "noopener", title }, "Jarl " + (b.tag || b.commit ? b.label : b.version)));
}

function renderNav() {
  mount(navEl, navItems.map(([key, href, label]) => h("a", { href, class: current.nav === key ? "active" : "" }, label)));
}

// renderBar shows the pending-changes bar (only while there are pending
// changes) and the small review/live switch in the header.
function renderBar() {
  if (!barEl) return;
  const d = state.draft;
  const n = d ? (d.ops || []).length : 0;
  if (modeHolder) {
    const live = state.immediate;
    mount(modeHolder, h("button", {
      type: "button", class: "mode-toggle" + (live ? " live" : ""), "aria-pressed": live ? "true" : "false",
      title: live ? "Edits are applied to named right away. Click to collect them for review first."
        : "Edits are collected as pending changes and applied from Changes. Click to apply edits right away.",
      onclick: () => setImmediate(!live),
    }, h("span", { class: "dot" }), live ? "Live edits" : "Review edits"));
  }
  mount(barEl, n > 0 ? h("div", { class: "pending-bar" },
    h("strong", null, plural(n, "pending change")),
    h("span", { class: "muted" }, "Your edits are collected in changeset #" + d.id + " and are not live yet."),
    h("a", { class: "button small", href: "#/changes" }, "Review"),
    h("button", { class: "primary small apply-now", title: "Apply the pending changes now, without reviewing them first", onclick: (ev) => applyDraft(ev.target, d) }, "Apply now")) : null);
}

// applyDraft applies the draft changeset from the banner and stays on the
// page. If it is refused, a dialog says why and links to Changes.
async function applyDraft(btn, d) {
  btn.disabled = true;
  btn.textContent = "Applying…";
  try {
    const r = await api("POST", "/changesets/" + d.id + "/apply", { body: {} });
    const res = r.result || {};
    toast("Applied changeset #" + d.id + (res.reloaded && res.reloaded.length ? " — named reloaded" : ""));
    (r.warnings || []).forEach((w) => toast(w, "warn", 10000));
    useDraft(null);
    rerender();
  } catch (e) {
    btn.disabled = false;
    btn.textContent = "Apply now";
    const review = await modal("The changes were not applied", errorBox(e), [{ label: "Close", value: false }, { label: "Review changes", kind: "primary", value: true }], { wide: true });
    if (review) location.hash = "#/changes";
  }
}

async function logout() {
  try { await api("POST", "/auth/logout"); } catch { /* ignore */ }
  state.me = null;
  state.csrf = "";
  renderLogin("You have logged out.");
}

async function route() {
  if (!state.me) return;
  const { path, query } = parseHash();
  for (const r of routes) {
    const m = path.match(r.pattern);
    if (!m) continue;
    const params = {};
    (r.params || []).forEach((p, i) => { params[p] = m[i + 1]; });
    current = { key: path, nav: r.nav, page: r.page, params, query };
    if (!r.params && r.nav) lastList[r.nav] = location.hash;
    renderNav();
    // Keep the old page until the new one is drawn (switching a zone's
    // tabs shouldn't blank the page); say "Loading…" only when it's slow.
    // (Only while the new page has drawn nothing yet: pages that draw
    // their frame first fill it in afterwards.)
    const gen = ++routeGen;
    const old = mainEl.firstChild;
    const slow = setTimeout(() => { if (gen === routeGen && mainEl.firstChild === old) mount(mainEl, h("div", { class: "muted" }, "Loading…")); }, 300);
    try {
      await r.page.render(mainEl, params, query);
    } catch (e) {
      if (gen === routeGen) mount(mainEl, h("h1", null, "Something went wrong"), errorBox(e));
    } finally {
      clearTimeout(slow);
    }
    return;
  }
  mount(mainEl, h("h1", null, "Not found"), h("p", null, h("a", { href: "#/" }, "Back to the dashboard")));
}

// rerender redraws the current page (after changes).
export function rerender() {
  if (current.page) route();
}

async function start() {
  layout();
  await loadDraft();
  onChange(renderBar);
  window.addEventListener("hashchange", route);
  await route();
}

setUnauthorizedHandler(() => {
  if (state.me) {
    state.me = null;
    renderLogin("Your session has expired. Please log in again.");
  }
});

setCodePrompt(totp.askCode);

(async function boot() {
  try {
    await loggedIn(await get("/auth/whoami"));
  } catch (e) {
    if (e.status === 401) renderLogin();
    else mount(app, h("div", { class: "login panel" }, h("h1", null, "Jarl"), errorBox(e)));
  }
})();

window.addEventListener("unhandledrejection", (e) => {
  toast(e.reason && e.reason.message ? e.reason.message : String(e.reason), "err");
});