let state;
let groups = [];
let selectedIndex = -1;
let currentPdfUrl = "";

const people = document.querySelector("#people");
const fields = document.querySelector("#fields");
const pdf = document.querySelector("#pdf");
const viewer = document.querySelector(".viewer");
const pdfMessage = document.querySelector("#pdfMessage");
const status = document.querySelector("#status");
const search = document.querySelector("#search");
const errorBanner = document.querySelector("#errorBanner");

const fieldDefs = [
  ["Name / Company", "name_company"],
  ["Prospective Buyer", "prospective_buyer"],
  ["Company", "company"],
  ["Phone", "phone"],
  ["Cell", "cell"],
  ["Email", "email"],
  ["Address", "address"],
  ["State", "state"],
  ["How did you hear", "how_did_you_hear"],
  ["Interested in updates", "interested_in_updates"],
  ["Background experience", "background_experience"],
  ["Types of businesses", "types_of_business_raw"],
  ["Businesses from Notes", "notes_business_raw"],
  ["Date of Introduction", "date_of_introduction"],
  ["Down payment", "down_payment_raw"],
  ["Total purchase price", "total_purchase_price"],
  ["Notes Page", "_notes_page"],
  ["Buyer Info Page", "_info_page"],
  ["CA Page", "_ca_page"],
];

const esc = (value) => String(value ?? "").replace(/[&<>"']/g, (char) => ({
  "&": "&amp;", "<": "&lt;", ">": "&gt;", '"': "&quot;", "'": "&#39;",
})[char]);

function buildGroups(docs) {
  const map = new Map();
  docs.forEach((doc, index) => {
    const key = doc.name_from_filename;
    const group = map.get(key) || {
      key,
      displayName: doc.prospective_buyer || key,
      docs: [],
      text: "",
    };
    group.docs.push({ ...doc, index });
    group.text += " " + [
      key,
      doc.prospective_buyer,
      doc.types_of_business_raw,
      doc.notes_business_raw,
      doc.address,
    ].filter(Boolean).join(" ");
    map.set(key, group);
  });
  return [...map.values()].sort((a, b) => a.key.localeCompare(b.key));
}

function visibleGroups() {
  const terms = search.value.toLowerCase().trim().split(/\s+/).filter(Boolean);
  return groups.filter((group) => terms.every((term) => group.text.toLowerCase().includes(term)));
}

function updateStatus(shownCount = visibleGroups().length) {
  const source = state.dataSource === "sample" ? "sample data" : "JSON file";
  status.textContent = `${shownCount} people / ${state.documents.length} documents · ${source}`;
  status.className = "";
}

function showError(message) {
  errorBanner.textContent = message;
  errorBanner.hidden = !message;
}

function renderList() {
  const shown = visibleGroups();
  people.innerHTML = shown.map((group) => `
    <div class="person">
      <div class="person-title">${esc(group.displayName)} <span class="muted">(${group.docs.length})</span></div>
      ${group.docs.map((doc) => `
        <button class="doc ${doc.index === selectedIndex ? "active" : ""}" data-index="${doc.index}">
          ${esc(doc.file_name)}
        </button>`).join("")}
    </div>
  `).join("");
  updateStatus(shown.length);
}

async function loadPdf(index) {
  if (currentPdfUrl) {
    URL.revokeObjectURL(currentPdfUrl);
    currentPdfUrl = "";
  }
  pdf.removeAttribute("src");
  viewer.classList.remove("loaded");
  pdfMessage.hidden = false;
  pdfMessage.textContent = "Loading PDF…";

  try {
    const response = await fetch(`/api/pdf?index=${index}`, { cache: "no-store" });
    if (!response.ok) {
      const body = await response.json().catch(() => ({}));
      throw new Error(body.error || `PDF request failed with HTTP ${response.status}.`);
    }
    const blob = await response.blob();
    currentPdfUrl = URL.createObjectURL(blob);
    pdf.src = currentPdfUrl;
    viewer.classList.add("loaded");
    pdfMessage.hidden = true;
  } catch (error) {
    const message = error instanceof Error ? error.message : String(error);
    pdfMessage.textContent = `Cannot open PDF: ${message}`;
    pdfMessage.hidden = false;
  }
}

function select(index) {
  selectedIndex = index;
  const doc = state.documents[index];
  if (!doc) return;
  fields.innerHTML = `
    <h2>${esc(doc.name_from_filename)}</h2>
    <p class="muted">${esc(doc.file_name)} · ${esc(doc._doc_type || "unknown")} · ${esc(doc._pages_total ?? "?")} pages</p>
    ${doc._vision_error ? `<p class="error">Vision error: ${esc(doc._vision_error)}</p>` : ""}
    ${fieldDefs.map(([label, key]) => `
      <div class="field"><b>${label}</b><div>${esc(doc[key] || "—")}</div></div>
    `).join("")}
  `;
  void loadPdf(index);
  renderList();
}

people.addEventListener("click", (event) => {
  const button = event.target.closest("[data-index]");
  if (button) select(Number(button.dataset.index));
});

search.addEventListener("input", renderList);

document.addEventListener("keydown", (event) => {
  if (["INPUT", "TEXTAREA"].includes(document.activeElement.tagName)) return;
  if (event.key === "ArrowDown" || event.key === "ArrowUp") {
    event.preventDefault();
    const delta = event.key === "ArrowDown" ? 1 : -1;
    select(Math.max(0, Math.min(state.documents.length - 1, selectedIndex < 0 ? 0 : selectedIndex + delta)));
  }
});

const dialog = document.querySelector("#settingsDialog");
const jsonPath = document.querySelector("#jsonPath");
const pdfBase = document.querySelector("#pdfBase");
const settingsError = document.querySelector("#settingsError");
const saveSettings = document.querySelector("#saveSettings");

document.querySelector("#settings").onclick = () => {
  jsonPath.value = state.config.jsonPath;
  pdfBase.value = state.config.pdfBaseDirectory;
  settingsError.hidden = true;
  settingsError.textContent = "";
  dialog.showModal();
};

saveSettings.onclick = async (event) => {
  event.preventDefault();
  saveSettings.disabled = true;
  settingsError.hidden = true;

  try {
    const response = await fetch("/api/config", {
      method: "POST",
      headers: { "content-type": "application/json" },
      body: JSON.stringify({
        jsonPath: jsonPath.value,
        pdfBaseDirectory: pdfBase.value,
      }),
    });
    const body = await response.json();
    if (!response.ok) throw new Error(body.error || "Could not save settings.");
    dialog.close();
    await load();
  } catch (error) {
    settingsError.textContent = error instanceof Error ? error.message : String(error);
    settingsError.hidden = false;
  } finally {
    saveSettings.disabled = false;
  }
};

async function load() {
  try {
    const response = await fetch("/api/state", { cache: "no-store" });
    if (!response.ok) throw new Error(`State request failed with HTTP ${response.status}.`);
    state = await response.json();
    groups = buildGroups(state.documents);
    showError(state.loadError || "");
    renderList();
    if (state.documents.length) select(0);
  } catch (error) {
    showError(error instanceof Error ? error.message : String(error));
  }
}

void load();