const loginView = document.querySelector("#login-view");
const chatView = document.querySelector("#chat-view");
const loginForm = document.querySelector("#login-form");
const loginError = document.querySelector("#login-error");
const messages = document.querySelector("#messages");
const chatForm = document.querySelector("#chat-form");
const messageInput = document.querySelector("#message");
const sendButton = document.querySelector("#send");
const logoutButton = document.querySelector("#logout");
const activeFocus = document.querySelector("#active-focus");
const todayList = document.querySelector("#today-list");
const refreshToday = document.querySelector("#refresh-today");
const historyList = document.querySelector("#history-list");
const navTabs = Array.from(document.querySelectorAll(".nav-tab"));

let token = sessionStorage.getItem("domovoy.chat.token") || "";
let conversationID = sessionStorage.getItem("domovoy.chat.conversation") || "";
let localHistory = [];

function showChat() {
  loginView.hidden = true;
  chatView.hidden = false;
  if (!messages.children.length) {
    appendMessage("assistant", "Я рядом. Напишите обычное сообщение, без внутренних идентификаторов.");
  }
  messageInput.focus();
}

function showLogin() {
  chatView.hidden = true;
  loginView.hidden = false;
}

function appendMessage(kind, text, meta = "") {
  const node = document.createElement("div");
  node.className = `message ${kind}`;
  node.textContent = text;
  if (meta) {
    const small = document.createElement("small");
    small.textContent = meta;
    node.appendChild(small);
  }
  messages.appendChild(node);
  messages.scrollTop = messages.scrollHeight;
  localHistory.push({kind, text, meta, at: new Date()});
  renderHistory();
}

function updateActiveFocus(value, provenance = "") {
  if (!activeFocus) return;
  activeFocus.textContent = value ? `Сейчас обсуждаем: ${value}` : "";
  activeFocus.hidden = !value;
}

async function api(path, options = {}) {
  const headers = {"Content-Type": "application/json", ...(options.headers || {})};
  if (token) headers.Authorization = `Bearer ${token}`;
  const response = await fetch(path, {...options, headers});
  if (!response.ok) throw new Error(await response.text());
  return response.json();
}

function humanMeta(result) {
  if (result.reminder_scheduled) return "Напоминание сохранено. Я вернусь к нему сам.";
  if (result.capability_status && result.capability_status !== "AVAILABLE") return "Возможность пока не подключена.";
  if (result.work_planned) return "Я разложил это как работу.";
  return "";
}

function renderHistory() {
  if (!historyList) return;
  historyList.replaceChildren();
  const items = localHistory.slice(-30).reverse();
  if (!items.length) {
    const empty = document.createElement("p");
    empty.className = "empty-state";
    empty.textContent = "История появится после сообщений в этом окне.";
    historyList.appendChild(empty);
    return;
  }
  for (const item of items) {
    const row = document.createElement("article");
    row.className = `history-item ${item.kind}`;
    const title = document.createElement("strong");
    title.textContent = item.kind === "user" ? "Вы" : "Домовой";
    const body = document.createElement("p");
    body.textContent = item.text;
    const time = document.createElement("span");
    time.textContent = item.at.toLocaleTimeString("ru-RU", {hour: "2-digit", minute: "2-digit"});
    row.append(title, body, time);
    historyList.appendChild(row);
  }
}

async function loadToday() {
  if (!todayList || !token) return;
  todayList.replaceChildren();
  const loading = document.createElement("p");
  loading.className = "empty-state";
  loading.textContent = "Смотрю, что требует внимания...";
  todayList.appendChild(loading);
  try {
    const result = await api("/api/today", {method: "GET"});
    todayList.replaceChildren();
    const items = result.Items || result.items || [];
    if (!items.length) {
      const empty = document.createElement("p");
      empty.className = "empty-state";
      empty.textContent = "Сейчас ничего срочного не требует внимания.";
      todayList.appendChild(empty);
      return;
    }
    for (const item of items) {
      const card = document.createElement("article");
      card.className = "attention-card";
      const when = document.createElement("time");
      const stamp = item.WhenUnixMillis || item.when_unix_millis || 0;
      when.textContent = stamp ? new Date(stamp).toLocaleString("ru-RU", {day: "2-digit", month: "2-digit", hour: "2-digit", minute: "2-digit"}) : "сейчас";
      const title = document.createElement("h2");
      title.textContent = item.Title || item.title || "Событие Домового";
      const state = document.createElement("p");
      state.textContent = item.HumanState || item.human_state || "ожидает внимания";
      const source = document.createElement("small");
      source.textContent = [item.SourceDescription || item.source_description, item.DeliveryState || item.delivery_state].filter(Boolean).join(" · ");
      const hintText = item.ResponseHint || item.response_hint || "";
      const actions = document.createElement("div");
      actions.className = "attention-actions";
      for (const [label, text] of [["Готово", "Готово"], ["Отложить", "Отложи на 10 минут"], ["Отменить", "Отмени"]]) {
        const button = document.createElement("button");
        button.type = "button";
        button.textContent = label;
        button.addEventListener("click", async () => {
          await sendChatMessage(text, {silentUser: false});
          await loadToday();
          activateTab("chat-panel");
        });
        actions.appendChild(button);
      }
      if (hintText) {
        const hint = document.createElement("small");
        hint.textContent = hintText;
        card.append(when, title, state, source, hint, actions);
      } else {
        card.append(when, title, state, source, actions);
      }
      todayList.appendChild(card);
    }
  } catch {
    todayList.replaceChildren();
    const error = document.createElement("p");
    error.className = "empty-state error";
    error.textContent = "Внимание сейчас недоступно. Чат можно продолжать.";
    todayList.appendChild(error);
  }
}

async function sendChatMessage(text, options = {}) {
  const clean = text.trim();
  if (!clean) return;
  if (!options.silentUser) appendMessage("user", clean);
  sendButton.disabled = true;
  try {
    const result = await api("/api/chat/messages", {method: "POST", body: JSON.stringify({conversation_id: conversationID, message: clean})});
    conversationID = result.conversation_id;
    sessionStorage.setItem("domovoy.chat.conversation", conversationID);
    updateActiveFocus(result.active_focus, result.project_provenance);
    appendMessage("assistant", result.reply_text || "Сообщение записано.", humanMeta(result));
    if (/что сейчас требует моего внимания/i.test(clean)) {
      await loadToday();
      activateTab("today-panel");
    }
  } catch {
    appendMessage("assistant", "Чат сейчас недоступен. Сообщение не принято runtime.");
  } finally {
    sendButton.disabled = false;
    messageInput.focus();
  }
}

function activateTab(panelID) {
  for (const tab of navTabs) tab.classList.toggle("active", tab.dataset.tab === panelID);
  for (const panel of document.querySelectorAll(".surface-panel")) {
    const active = panel.id === panelID;
    panel.hidden = !active;
    panel.classList.toggle("active-panel", active);
  }
  if (panelID === "today-panel") loadToday();
  if (panelID === "history-panel") renderHistory();
}

loginForm.addEventListener("submit", async (event) => {
  event.preventDefault();
  loginError.textContent = "";
  const username = document.querySelector("#username").value;
  const password = document.querySelector("#password").value;
  try {
    const result = await api("/api/session", {method: "POST", body: JSON.stringify({username, password})});
    token = result.Token || result.token;
    sessionStorage.setItem("domovoy.chat.token", token);
    showChat();
  } catch {
    loginError.textContent = "Вход не выполнен";
  }
});

chatForm.addEventListener("submit", async (event) => {
  event.preventDefault();
  const text = messageInput.value.trim();
  if (!text) return;
  messageInput.value = "";
  await sendChatMessage(text);
});

for (const tab of navTabs) {
  tab.addEventListener("click", () => activateTab(tab.dataset.tab));
}

if (refreshToday) refreshToday.addEventListener("click", loadToday);

logoutButton.addEventListener("click", () => {
  token = "";
  conversationID = "";
  sessionStorage.removeItem("domovoy.chat.token");
  sessionStorage.removeItem("domovoy.chat.conversation");
  messages.replaceChildren();
  updateActiveFocus("");
  showLogin();
});

if (token) {
  showChat();
} else {
  showLogin();
}