// events page — list + title edit + detach-and-delete, with filters
// filter/sort/pagination state persists to url query params
// depends on: app.js

let eventOffset = 0;
let currentEvent = null;


function getEventFilters() {
  return {
    keyword:      document.getElementById("ef-keyword").value.trim(),
    min_articles: document.getElementById("ef-min").value.trim(),
    from:         document.getElementById("ef-from").value,
    to:           document.getElementById("ef-to").value,
    sort:         document.getElementById("ef-sort").value,
  };
}


function syncUrl() {
  const f = getEventFilters();
  queryWrite({
    ...f,
    // default sort isn't worth surfacing in the url
    sort: f.sort && f.sort !== "created_desc" ? f.sort : "",
    offset: eventOffset > 0 ? eventOffset : "",
  });
}


async function loadEvents() {
  const f = getEventFilters();
  const params = new URLSearchParams({ limit: PAGE, offset: eventOffset });
  if (f.keyword)      params.set("keyword", f.keyword);
  if (f.min_articles) params.set("min_articles", f.min_articles);
  if (f.from)         params.set("from", f.from + "T00:00:00");
  if (f.to)           params.set("to", f.to + "T23:59:59");
  if (f.sort)         params.set("sort", f.sort);

  const data = await api(`/admin/api/events?${params}`);
  const tbody = document.getElementById("eventTable");

  tbody.innerHTML = data.rows.map(r => `
    <tr>
      <td style="color:var(--muted-dark); font-size:12px">${r.id}</td>
      <td><span class="truncate" title="${escapeHtml(r.title)}">${escapeHtml(r.title)}</span></td>
      <td>${r.article_count}</td>
      <td style="color:var(--muted-dark); white-space:nowrap; font-size:12px">${r.created_at ? r.created_at.slice(0, 16) : "—"}</td>
      <td><button onclick='openEvent(${r.id}, ${JSON.stringify(r.title)})'>Edit</button></td>
    </tr>
  `).join("");

  const total = data.total;
  document.getElementById("ePageInfo").textContent =
    `${eventOffset + 1}–${Math.min(eventOffset + PAGE, total)} of ${total.toLocaleString()}`;
  document.getElementById("ePrevBtn").disabled = eventOffset === 0;
  document.getElementById("eNextBtn").disabled = eventOffset + PAGE >= total;
}


function openEvent(id, title) {
  currentEvent = { id, title };
  document.getElementById("em-title").value = title;
  document.getElementById("eventOverlay").classList.add("open");
}


document.addEventListener("DOMContentLoaded", () => {

  // restore filter state from url
  queryApplyToInputs({
    "ef-keyword": "keyword",
    "ef-min":     "min_articles",
    "ef-from":    "from",
    "ef-to":      "to",
    "ef-sort":    "sort",
  });
  eventOffset = parseInt(queryGet("offset"), 10) || 0;


  document.getElementById("eSearchBtn").onclick = () => {
    eventOffset = 0;
    syncUrl();
    loadEvents();
  };

  document.getElementById("ePrevBtn").onclick = () => {
    eventOffset = Math.max(0, eventOffset - PAGE);
    syncUrl();
    loadEvents();
  };
  document.getElementById("eNextBtn").onclick = () => {
    eventOffset += PAGE;
    syncUrl();
    loadEvents();
  };

  document.querySelector(".filters").addEventListener("keydown", e => {
    if (e.key === "Enter") {
      eventOffset = 0;
      syncUrl();
      loadEvents();
    }
  });

  document.getElementById("eCancelBtn").onclick = () =>
    document.getElementById("eventOverlay").classList.remove("open");

  document.getElementById("eSaveBtn").onclick = async () => {
    if (!currentEvent) return;
    try {
      await api(`/admin/api/events/${currentEvent.id}`, {
        method: "PATCH",
        headers: { "Content-Type": "application/json" },
        body: JSON.stringify({ title: document.getElementById("em-title").value }),
      });
      document.getElementById("eventOverlay").classList.remove("open");
      toast("Saved");
      loadEvents();
    } catch (e) { toast("Save failed", true); }
  };

  document.getElementById("eDeleteBtn").onclick = async () => {
    if (!currentEvent) return;
    if (!confirm(`Delete event #${currentEvent.id}? Articles will be detached but not deleted.`)) return;
    try {
      await api(`/admin/api/events/${currentEvent.id}`, { method: "DELETE" });
      document.getElementById("eventOverlay").classList.remove("open");
      toast("Event deleted");
      loadEvents();
      loadGlobalStats();
    } catch (e) { toast("Delete failed", true); }
  };


  loadEvents();
});