// Hound Antivirus — webview front-end.
// Thin view over houndd via Tauri commands; 6-tab layout.
// No bundler here — the webview loads this file directly, so a bare module
// specifier ("@tauri-apps/api/core") cannot be resolved and the entire script
// fails to parse. The window then sits on its static HTML forever, looking
// exactly like a daemon that never answered. The API comes off the global
// that `withGlobalTauri` installs instead.
const { invoke } = window.__TAURI__.core;
const { listen } = window.__TAURI__.event;

const $ = (id) => document.getElementById(id);

/// Paint the chosen theme. "auto" defers to the desktop, which the webview
/// reports through prefers-color-scheme — and which can change while the app
/// is open, so the listener stays attached rather than sampling once.
const SYSTEM_DARK = window.matchMedia("(prefers-color-scheme: dark)");
let themeChoice = "auto";
function applyTheme(choice) {
  themeChoice = choice || "auto";
  const dark = themeChoice === "dark" || (themeChoice === "auto" && SYSTEM_DARK.matches);
  document.documentElement.setAttribute("data-theme", dark ? "dark" : "light");
  // The tray needs this too: which monochrome tone to draw depends on it,
  // and only the webview can resolve "follow system".
  invoke("set_theme_resolved", { dark }).catch(() => {});
}
SYSTEM_DARK.addEventListener("change", () => {
  if (themeChoice === "auto") applyTheme("auto");
});

// The daemon refuses anything that writes unless the caller is root, because
// quarantine restores files back out as root and that is not something group
// membership should confer. The app runs as you, so those actions need a
// terminal for now. Translate the wire error rather than showing it raw.
function explain(e) {
  const raw = String(e && e.message ? e.message : e);
  const m = raw.match(/([a-z.]+) requires administrator privileges/);
  if (m) {
    return "That needs administrator rights. Run it from a terminal: sudo hound " +
      ({
        "settings.set": "settings …",
        "update": "update",
        "quarantine.add": "quarantine add <file>",
        "quarantine.restore": "quarantine restore <id>",
        "quarantine.remove": "quarantine remove <id>",
        "events.clear": "alerts clear",
        "realtime.set_enabled": "settings realtime on|off",
      }[m[1]] || m[1]);
  }
  if (/cannot read .* as uid/.test(raw)) {
    return raw.replace(/^.*?cannot read/, "Hound will not scan") +
      " (it only scans files you could open yourself).";
  }
  return raw.replace(/^daemon error -?\d+: /, "");
}

const ICONS = {
  protected: "state-protected-48.png",
  scanning:  "state-scanning-48.png",
  threat:    "state-threat-48.png",
  paused:    "state-paused-48.png",
};

const TITLES = {
  protected: "Protected",
  scanning:  "Scanning…",
  threat:    "Threat Detected",
  paused:    "Paused",
};

const SUBS = {
  protected: "Your system looks healthy.",
  scanning:  "Hound is working the queue.",
  threat:    "We found something that should not be there.",
  paused:    "Real-time protection is off.",
};

let currentState = "protected";
let busy = false;
let paused = false;

// ── Tabs ───────────────────────────────────────────────────────────
const LOADERS = {
  quarantine: loadQuarantine,
  realtime:   loadRealtime,
  rootkit:    null, // on demand
  alerts:     loadAlerts,
  settings:   loadSettings,
};

function switchTab(name) {
  document.querySelectorAll(".tab").forEach((t) =>
    t.classList.toggle("active", t.dataset.tab === name));
  document.querySelectorAll(".tab-panel").forEach((p) =>
    p.classList.toggle("active", p.id === "panel-" + name));
  const fn = LOADERS[name];
  if (fn) fn().catch(() => {});
}

document.querySelectorAll(".tab").forEach((t) =>
  t.addEventListener("click", () => switchTab(t.dataset.tab)));

// ── State rendering (hero + tray) ─────────────────────────────────
function setState(state) {
  if (!ICONS[state]) state = "protected";
  currentState = state;
  $("hero").dataset.state = state;
  $("shield-icon").src = ICONS[state];
  $("hero-title").textContent = TITLES[state];
  $("hero-sub").textContent = SUBS[state];
  invoke("set_state", { state }).catch(() => {});
}

function setEngineDot(cls, label) {
  $("engine-dot").className = "engine-dot " + cls;
  $("engine-label").textContent = label;
}

function fmtDbAge(iso) {
  const t = new Date(iso);
  if (Number.isNaN(t.getTime())) return iso;
  const days = Math.floor((Date.now() - t.getTime()) / 86400000);
  if (days <= 0) return "today";
  if (days === 1) return "1 day ago";
  if (days < 30) return `${days} days ago`;
  const mo = Math.floor(days / 30);
  return `${mo} month${mo > 1 ? "s" : ""} ago`;
}

function renderStatus(st) {
  setEngineDot(st.engine_present ? "ok" : "bad",
    st.engine_present ? `engine online (${st.engine || "unknown"})` : "engine offline");
  $("pill-os").textContent = "OS: " + (st.os || "—");
  $("pill-engine").textContent = "engine: " + (st.engine || "—");
  // The footer used to claim ClamAV. It reports whatever the daemon actually
  // loaded, which has been yara-x since the engine was replaced.
  $("foot-engine").textContent = "engine: " + (st.engine || "—");
  const pill = $("pill-db");
  if (st.db) {
    pill.textContent = "signatures: " + fmtDbAge(st.db.updated_at);
    const staleDays = (Date.now() - new Date(st.db.updated_at).getTime()) / 86400000;
    pill.classList.toggle("stale", staleDays > 3);
    $("foot-ver").textContent = `houndd ${st.daemon_version} · ${st.db.file}`;
  } else {
    pill.textContent = "signatures: none";
    pill.classList.add("stale");
    $("foot-ver").textContent = `houndd ${st.daemon_version}`;
  }
}

// ── Scans ──────────────────────────────────────────────────────────
async function doScan(path) {
  if (busy) return;
  busy = true;
  setButtons(true);
  $("scan-panel").classList.remove("hidden");
  $("scan-panel").querySelector(".progress").classList.add("indeterminate");
  $("scan-title").textContent = "Scanning…";
  $("scan-target").textContent = path;
  setState("scanning");
  try {
    const r = await invoke("scan", { path, recursive: true });
    renderScanResult(r, path);
  } catch (e) {
    $("scan-note").textContent = "Scan failed: " + explain(e);
    setState(paused ? "paused" : "protected");
  } finally {
    busy = false;
    setButtons(false);
    $("scan-panel").querySelector(".progress").classList.remove("indeterminate");
  }
}

function renderScanResult(r, path) {
  const clean = r.infected === 0;
  setState(clean ? (paused ? "paused" : "protected") : "threat");
  $("scan-title").textContent = clean
    ? "Scan complete — clean"
    : `Scan complete — ${r.infected} threat${r.infected > 1 ? "s" : ""}`;
  $("scan-note").textContent =
    `${r.scanned.toLocaleString()} files scanned · ${r.clean.toLocaleString()} clean · ${r.infected.toLocaleString()} infected`;
  $("progress-bar").style.width = "100%";

  $("results-meta").textContent = `${r.scanned} files · ${path}`;
  const body = $("results-body");
  body.innerHTML = "";
  if (clean) {
    body.innerHTML =
      `<div class="result-row clean">
         <span class="sig">✔ All clear</span>
         <span class="path">${r.scanned.toLocaleString()} files scanned, nothing flagged</span>
         <span></span>
       </div>`;
  } else {
    for (const f of r.found.slice(0, 50)) {
      const div = document.createElement("div");
      div.className = "result-row infected";
      div.innerHTML =
        `<span class="sig">✘ ${escapeHtml(f.virus)}</span>
         <span class="path" title="${escapeHtml(f.path)}">${escapeHtml(f.path)}</span>
         <span></span>`;
      body.appendChild(div);
    }
    if (r.found.length > 50) {
      const more = document.createElement("div");
      more.className = "muted";
      more.style.padding = "4px 2px";
      more.textContent = `…and ${r.found.length - 50} more`;
      body.appendChild(more);
    }
  }
}

// ── Signature update ───────────────────────────────────────────────
async function doUpdate() {
  if (busy) return;
  busy = true;
  setButtons(true);
  $("update-panel").classList.remove("hidden");
  const log = $("update-log");
  log.className = "log";
  log.textContent = "Running freshclam — this can take a minute…\n";
  try {
    const u = await invoke("update");
    log.textContent = u.output.trim();
    log.className = "log " + (u.ok ? "ok" : "fail");
    if (u.status) renderStatus(u.status);
    setState(paused ? "paused" : "protected");
  } catch (e) {
    log.textContent = "Update failed: " + explain(e);
    log.className = "log fail";
  } finally {
    busy = false;
    setButtons(false);
  }
}

// ── Quarantine tab ─────────────────────────────────────────────────
function fmtSize(bytes) {
  if (bytes < 1024) return bytes + " B";
  const units = ["KB", "MB", "GB", "TB"];
  let v = bytes, i = -1;
  while (v >= 1024 && i < units.length - 1) { v /= 1024; i++; }
  return v.toFixed(v < 10 ? 1 : 0) + " " + units[i];
}

function fmtTime(iso) {
  const t = new Date(iso);
  if (Number.isNaN(t.getTime())) return iso;
  return t.toLocaleString();
}

function setQuarantineBadge(n) {
  const b = $("badge-quarantine");
  b.classList.toggle("hidden", n === 0);
  b.textContent = n;
}

async function loadQuarantine() {
  try {
    const list = await invoke("quarantine_list");
    const body = $("qt-body");
    body.innerHTML = "";
    setQuarantineBadge(list.length);
    $("qt-count").textContent = list.length
      ? `${list.length} item${list.length > 1 ? "s" : ""} held`
      : "vault is empty";
    if (!list.length) {
      body.innerHTML = '<p class="muted empty">Nothing in quarantine. Your clean system thanks you.</p>';
      return;
    }
    for (const e of list) {
      const row = document.createElement("div");
      row.className = "qt-row" + (e.restored ? " restored" : "");
      row.innerHTML =
        `<span class="qt-virus">${escapeHtml(e.virus)}</span>
         <span>
           <span class="qt-path" title="${escapeHtml(e.original_path)}">${escapeHtml(e.original_path)}</span><br/>
           <span class="qt-meta">${fmtSize(e.size)} · quarantined ${fmtTime(e.ts)}${e.restored ? " · restored" : ""}</span>
         </span>
         <span class="qt-actions"></span>`;
      const actions = row.querySelector(".qt-actions");
      if (!e.restored) {
        const rb = document.createElement("button");
        rb.className = "btn small";
        rb.textContent = "Restore";
        rb.onclick = async () => {
          rb.disabled = true;
          try { await invoke("quarantine_restore", { id: e.id }); loadQuarantine(); }
          catch (err) { rb.disabled = false; alert("Restore failed: " + err); }
        };
        actions.appendChild(rb);
      }
      const xb = document.createElement("button");
      xb.className = "btn small danger";
      xb.textContent = "Remove";
      xb.onclick = async () => {
        if (!confirm(`Remove ${e.virus} from the vault? The bytes are deleted for good.`)) return;
        xb.disabled = true;
        try { await invoke("quarantine_remove", { id: e.id }); loadQuarantine(); }
        catch (err) { xb.disabled = false; alert("Remove failed: " + err); }
      };
      actions.appendChild(xb);
      body.appendChild(row);
    }
  } catch (e) {
    $("qt-body").innerHTML = `<p class="muted empty">Failed to load: ${escapeHtml(explain(e))}</p>`;
  }
}

// ── Realtime tab ───────────────────────────────────────────────────
function fmtUptime(secs) {
  const h = Math.floor(secs / 3600), m = Math.floor((secs % 3600) / 60), s = secs % 60;
  if (h) return `${h}h ${m}m`;
  if (m) return `${m}m ${s}s`;
  return `${s}s`;
}

async function loadRealtime() {
  try {
    const rt = await invoke("realtime_status");
    const st = await invoke("settings");
    $("rt-toggle").checked = rt.enabled;
    $("rt-enabled-label").textContent = rt.enabled ? "monitor running" : "monitor off";
    $("rt-seen").textContent = rt.files_seen.toLocaleString();
    $("rt-quar").textContent = rt.files_quarantined.toLocaleString();
    $("rt-uptime").textContent = rt.active ? fmtUptime(rt.uptime_secs) : "—";
    const rw = $("rt-ransom");
    rw.textContent = rt.ransomware;
    rw.className = "stat-val " +
      (rt.ransomware === "alarm" ? "alarm" : rt.ransomware === "watching" ? "watching" : "calm");
    $("rt-watch").textContent = rt.watching.join(", ") || "—";
    $("rt-last").textContent = rt.last_event_at ? fmtTime(rt.last_event_at) : "none yet";
    $("rt-action").textContent = st.on_detect;
    const wl = $("rt-watch-list");
    wl.innerHTML = "";
    for (const dir of st.realtime_watch) {
      const chip = document.createElement("span");
      chip.className = "watch-chip";
      chip.textContent = dir;
      wl.appendChild(chip);
    }
  } catch (e) {
    $("rt-enabled-label").textContent = "error: " + explain(e);
  }
}

// ── Rootkit tab ────────────────────────────────────────────────────
async function runRootkit() {
  const btn = $("btn-rootkit");
  btn.disabled = true;
  btn.textContent = "Scanning…";
  $("rootkit-banner").classList.add("hidden");
  $("rootkit-body").innerHTML = '<p class="muted empty">Checking setuid bits, deleted executables, world-writable binaries…</p>';
  try {
    const r = await invoke("rootkit_scan");
    const banner = $("rootkit-banner");
    const dirty = r.critical + r.warn > 0;
    banner.textContent = dirty ? `⚠ ${r.verdict}` : `✔ ${r.verdict} — ${r.info} informational note${r.info === 1 ? "" : "s"}`;
    banner.className = "verdict " + (dirty ? "dirty" : "clean");
    banner.classList.remove("hidden");

    const body = $("rootkit-body");
    body.innerHTML = "";
    if (!r.findings.length) {
      body.innerHTML = '<p class="muted empty">No findings at all — squeaky clean.</p>';
      return;
    }
    const rank = { critical: 0, warn: 1, info: 2 };
    const sorted = [...r.findings].sort((a, b) => (rank[a.severity] ?? 3) - (rank[b.severity] ?? 3));
    for (const f of sorted) {
      const row = document.createElement("div");
      row.className = "finding-row";
      row.innerHTML =
        `<span class="sev ${escapeHtml(f.severity)}">${escapeHtml(f.severity)}</span>
         <span class="check">${escapeHtml(f.check)}</span>
         <span class="detail">${escapeHtml(f.detail)}</span>`;
      body.appendChild(row);
    }
  } catch (e) {
    $("rootkit-body").innerHTML = `<p class="muted empty">Scan failed: ${escapeHtml(explain(e))}</p>`;
  } finally {
    btn.disabled = false;
    btn.textContent = "Run Scan";
  }
}

// ── Alerts tab ─────────────────────────────────────────────────────
function setAlertsBadge(n) {
  const b = $("badge-alerts");
  b.classList.toggle("hidden", n === 0);
  b.textContent = n;
}

async function loadAlerts() {
  try {
    const list = await invoke("events", { limit: 200 });
    $("alerts-count").textContent = list.length ? `${list.length} events` : "";
    setAlertsBadge(list.filter((e) => e.severity === "critical").length);
    const body = $("alerts-body");
    body.innerHTML = "";
    if (!list.length) {
      body.innerHTML = '<p class="muted empty">No events yet — the dog hasn’t barked.</p>';
      return;
    }
    for (const e of list) {
      const row = document.createElement("div");
      row.className = "event-row";
      row.innerHTML =
        `<span class="ev-sev ${escapeHtml(e.severity)}">${escapeHtml(e.severity)}</span>
         <span class="ev-kind">${escapeHtml(e.kind)}</span>
         <span class="ev-msg">${escapeHtml(e.message)}</span>
         <span class="ev-ts">${fmtTime(e.ts)}</span>`;
      body.appendChild(row);
    }
  } catch (e) {
    $("alerts-body").innerHTML = `<p class="muted empty">Failed to load: ${escapeHtml(explain(e))}</p>`;
  }
}

// ── Settings tab ───────────────────────────────────────────────────
let settingsCache = null;

async function loadSettings() {
  try {
    const s = await invoke("settings");
    settingsCache = s;
    $("set-paused").checked = s.paused;
    $("set-autoupdate").checked = s.auto_update_signatures;
    $("set-notify").checked = s.notify_desktop;
    $("set-realtime").checked = s.realtime_enabled;
    $("set-watch").value = (s.realtime_watch || []).join("\n");
    $("set-ondetect").value = s.on_detect;
    $("set-maxsize").value = s.max_file_size_mb;
    $("set-excludes").value = (s.exclude_paths || []).join("\n");
    $("set-recursive").checked = s.recursive_default;
    $("set-ransom").checked = s.ransomware_guard;
    $("set-ransom-thresh").value = s.ransomware_threshold_per_min;
    $("set-rootkit").checked = s.rootkit_enabled;
    $("set-theme").value = s.theme || "auto";
    $("set-monochrome").checked = (s.tray_icon_style || "colour") === "monochrome";
    applyTheme(s.theme || "auto");
  } catch (e) {
    $("settings-msg").textContent = "Failed to load: " + explain(e);
  }
}

async function saveSettings() {
  if (!settingsCache) return;
  const s = settingsCache;
  s.paused = $("set-paused").checked;
  s.auto_update_signatures = $("set-autoupdate").checked;
  s.notify_desktop = $("set-notify").checked;
  s.realtime_enabled = $("set-realtime").checked;
  s.realtime_watch = $("set-watch").value.split("\n").map((x) => x.trim()).filter(Boolean);
  s.on_detect = $("set-ondetect").value;
  s.theme = $("set-theme").value;
  s.tray_icon_style = $("set-monochrome").checked ? "monochrome" : "colour";
  s.max_file_size_mb = Math.max(1, parseInt($("set-maxsize").value, 10) || 0);
  s.exclude_paths = $("set-excludes").value.split("\n").map((x) => x.trim()).filter(Boolean);
  s.recursive_default = $("set-recursive").checked;
  s.ransomware_guard = $("set-ransom").checked;
  s.ransomware_threshold_per_min = Math.max(10, parseInt($("set-ransom-thresh").value, 10) || 100);
  s.rootkit_enabled = $("set-rootkit").checked;
  try {
    const saved = await invoke("set_settings", { s });
    paused = saved.paused;
    $("btn-pause").textContent = paused ? "Resume Protection" : "Pause Protection";
    $("settings-msg").textContent = "Saved ✓";
    setTimeout(() => ($("settings-msg").textContent = ""), 2500);
    loadRealtime().catch(() => {});
  } catch (e) {
    $("settings-msg").textContent = explain(e);
  }
}

// ── Wiring ─────────────────────────────────────────────────────────
function setButtons(disabled) {
  for (const id of ["btn-scan-home", "btn-scan-custom", "btn-update", "btn-pause"])
    $(id).disabled = disabled;
}

function escapeHtml(s) {
  return String(s).replace(/[&<>\"]/g, (c) =>
    ({ "&": "&amp;", "<": "&lt;", ">": "&gt;", '"': "&quot;" }[c]));
}

async function pickFolder() {
  try {
    const { open } = await import("@tauri-apps/plugin-dialog");
    const dir = await open({ directory: true, multiple: false, title: "Choose a folder to scan" });
    if (dir) doScan(dir);
  } catch {
    const p = prompt("Folder to scan:");
    if (p) doScan(p);
  }
}

function togglePause() {
  paused = !paused;
  $("btn-pause").textContent = paused ? "Resume Protection" : "Pause Protection";
  setState(paused ? "paused" : "protected");
}

$("btn-scan-home").addEventListener("click", () => doScan("~"));
$("btn-scan-custom").addEventListener("click", pickFolder);
$("btn-update").addEventListener("click", doUpdate);
$("btn-pause").addEventListener("click", togglePause);
$("btn-qt-refresh").addEventListener("click", () => loadQuarantine());
$("btn-alerts-refresh").addEventListener("click", () => loadAlerts());
$("btn-rootkit").addEventListener("click", runRootkit);
$("btn-settings-save").addEventListener("click", saveSettings);

$("btn-qt-add").addEventListener("click", async () => {
  const path = $("qt-add-path").value.trim();
  const virus = $("qt-add-virus").value.trim() || "manual";
  if (!path) return alert("Enter a file path to quarantine.");
  try {
    await invoke("quarantine_add", { path, virus });
    $("qt-add-path").value = "";
    loadQuarantine();
  } catch (e) { alert("Quarantine failed: " + e); }
});

$("btn-alerts-clear").addEventListener("click", async () => {
  if (!confirm("Clear the whole event log?")) return;
  try {
    const n = await invoke("clear_events");
    $("alerts-count").textContent = `${n} event${n === 1 ? "" : "s"} cleared`;
    loadAlerts();
  } catch (e) { alert("Clear failed: " + e); }
});

$("rt-toggle").addEventListener("change", async (ev) => {
  try {
    await invoke("realtime_set_enabled", { enabled: ev.target.checked });
    loadRealtime();
  } catch (e) {
    ev.target.checked = !ev.target.checked;
    alert("Toggle failed: " + e);
  }
});

// Tray menu events (Scan Home / Scan Downloads / Update).
listen("tray-event", (e) => {
  const p = e.payload;
  if (p?.action === "scan" && p.path) {
    switchTab("protection");
    doScan(p.path);
  } else if (p?.action === "update") {
    switchTab("protection");
    doUpdate();
  }
});

// Initial boot.
async function boot() {
  try {
    const st = await invoke("status");
    renderStatus(st);
    if (st.engine_present) setState(paused ? "paused" : "protected");
    else setState("paused");
  } catch {
    setEngineDot("bad", "engine offline");
    setState("paused");
    $("hero-sub").textContent =
      "Can't reach houndd. Check that the service is up (`systemctl status houndd`). " +
      "If it is, you may not be in the `hound` group yet — the installer adds you, " +
      "but it only takes effect after you log out and back in.";
  }
}

// Tells the watchdog in index.html that the script actually ran.
window.__houndBooted = true;
$("set-theme").addEventListener("change", (e) => applyTheme(e.target.value));

boot();