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

let links = [];
let deleted = [];
let editing = false;
let editId = null;
let syncOn = false;
let syncState = ""; // "", "busy", "ok", "err"

const uid = () => Math.random().toString(36).slice(2, 10);

function normalizeUrl(raw) {
  raw = raw.trim();
  if (!/^[a-z][a-z0-9+.-]*:\/\//i.test(raw)) raw = "http://" + raw;
  try { return new URL(raw).href; } catch { return null; }
}

async function load() {
  const s = await LabSync.readLocal();
  links = s.links;
  deleted = s.deleted;
  // Einträge aus Version 1.0 haben noch keinen Zeitstempel
  if (links.some((l) => !l.updated)) {
    links = links.map((l) => ({ ...l, updated: l.updated || Date.now() }));
    await save(false);
  }
  render();
  syncOn = !!(await LabSync.getConfig())?.url;
  render();
  if (syncOn) runSync();
}

async function save(sync = true) {
  await LabSync.writeLocal({ links, deleted, modified: Date.now() });
  if (sync && syncOn) runSync();
}

async function runSync() {
  setSync("busy");
  try {
    await LabSync.sync();
    const s = await LabSync.readLocal();
    links = s.links;
    deleted = s.deleted;
    setSync("ok");
  } catch (e) {
    setSync("err", e.message);
  }
  render();
}

function setSync(state, msg = "") {
  syncState = state;
  $("syncBtn").title = msg || "Mit WebDAV synchronisieren";
}

function render() {
  const q = $("search").value.trim().toLowerCase();
  const list = $("list");
  list.textContent = "";

  const shown = links.filter((l) => !q || (l.name + " " + l.url).toLowerCase().includes(q));
  for (const l of shown) {
    const li = document.createElement("li");

    const a = document.createElement("a");
    a.href = l.url;
    a.target = "_blank";
    a.rel = "noopener";
    a.innerHTML = '<span class="ico"></span><span class="txt"><span class="name"></span><span class="url"></span></span>';
    a.querySelector(".ico").textContent = l.icon || "▣";
    a.querySelector(".name").textContent = l.name;
    a.querySelector(".url").textContent = l.url.replace(/^https?:\/\//, "").replace(/\/$/, "");
    if (editing) a.addEventListener("click", (e) => e.preventDefault());
    li.append(a);

    const eb = document.createElement("div");
    eb.className = "edit-btns";
    eb.append(
      btn("[✎]", () => openForm(l)),
      btn("[↑]", () => move(l.id, -1)),
      btn("[↓]", () => move(l.id, 1)),
      Object.assign(btn("[✕]", () => remove(l.id)), { className: "del" })
    );
    li.append(eb);
    list.append(li);
  }

  $("empty").hidden = links.length > 0 || !!editId;
  $("count").textContent = links.length ? `${links.length} Einträge` : "";
  document.body.classList.toggle("editing", editing);
  for (const id of ["add", "export", "import"]) $(id).hidden = !editing;
  $("editToggle").textContent = editing ? "[FERTIG]" : "[EDIT]";
  $("syncBtn").hidden = !syncOn;
  $("syncBtn").className = syncState;
}

function btn(label, fn) {
  const b = document.createElement("button");
  b.textContent = label;
  b.addEventListener("click", fn);
  return b;
}

async function move(id, dir) {
  const i = links.findIndex((l) => l.id === id);
  const j = i + dir;
  if (j < 0 || j >= links.length) return;
  [links[i], links[j]] = [links[j], links[i]];
  await save();
  render();
}

async function remove(id) {
  links = links.filter((l) => l.id !== id);
  deleted = [...deleted.filter((t) => t.id !== id), { id, updated: Date.now() }];
  await save();
  render();
}

function openForm(link) {
  editId = link ? link.id : "new";
  $("fIcon").value = link?.icon || "";
  $("fName").value = link?.name || "";
  $("fUrl").value = link?.url || "";
  $("form").hidden = false;
  $("fName").focus();
}
function closeForm() {
  editId = null;
  $("form").hidden = true;
  render();
}

$("form").addEventListener("submit", async (e) => {
  e.preventDefault();
  const url = normalizeUrl($("fUrl").value);
  if (!url) { $("fUrl").focus(); return; }
  const entry = { name: $("fName").value.trim(), url, icon: $("fIcon").value.trim(), updated: Date.now() };
  if (editId === "new") links.push({ id: uid(), ...entry });
  else Object.assign(links.find((l) => l.id === editId), entry);
  await save();
  closeForm();
});

$("cancel").addEventListener("click", closeForm);
$("add").addEventListener("click", () => openForm());
$("search").addEventListener("input", render);
$("editToggle").addEventListener("click", () => {
  editing = !editing;
  if (!editing) { editId = null; $("form").hidden = true; }
  render();
});
$("syncBtn").addEventListener("click", runSync);
$("settings").addEventListener("click", () => chrome.runtime.openOptionsPage());

// Enter im Suchfeld öffnet den ersten Treffer
$("search").addEventListener("keydown", (e) => {
  if (e.key === "Enter" && !editing) $("list").querySelector("a")?.click();
});

$("export").addEventListener("click", () => {
  const blob = new Blob([JSON.stringify(links, null, 2)], { type: "application/json" });
  const a = Object.assign(document.createElement("a"), { href: URL.createObjectURL(blob), download: "lablinks.json" });
  a.click();
  URL.revokeObjectURL(a.href);
});
$("import").addEventListener("click", () => $("file").click());
$("file").addEventListener("change", async (e) => {
  const file = e.target.files[0];
  if (!file) return;
  try {
    const arr = JSON.parse(await file.text());
    const now = Date.now();
    const imported = arr
      .filter((x) => x && x.name && x.url)
      .map((x) => ({ id: uid(), name: String(x.name), url: normalizeUrl(String(x.url)) || String(x.url), icon: x.icon || "", updated: now }));
    deleted = [...deleted, ...links.map((l) => ({ id: l.id, updated: now }))];
    links = imported;
    await save();
    render();
  } catch { alert("Ungültige JSON-Datei."); }
  e.target.value = "";
});

load();
$("search").focus();