const APP_CONFIG = window.APP_CONFIG || {};

const API_BASE = APP_CONFIG.API_BASE_URL || "https://api.corpus.swecha.org/api/v1";
const HF_API_BASE = APP_CONFIG.HF_API_BASE_URL || "https://api-inference.huggingface.co/models";
const HF_ASR_MODEL = APP_CONFIG.HF_ASR_MODEL || "viswamaicoe/swecha-gonthuka-asr";
const HF_TOKEN = APP_CONFIG.HF_TOKEN || "";
const LOCAL_ASR_BASE = (APP_CONFIG.LOCAL_ASR_BASE_URL !== undefined && APP_CONFIG.LOCAL_ASR_BASE_URL !== null && APP_CONFIG.LOCAL_ASR_BASE_URL !== "")
  ? APP_CONFIG.LOCAL_ASR_BASE_URL
  : "";
const CORPUS_ASR_ENDPOINT = APP_CONFIG.CORPUS_ASR_ENDPOINT || "";

// Auth elements
const loginPage = document.getElementById("loginPage");
const dashboard = document.getElementById("dashboard");
const phoneInput = document.getElementById("phoneInput");
const passwordInput = document.getElementById("passwordInput");
const loginBtn = document.getElementById("loginBtn");
const loginError = document.getElementById("loginError");
const logoutBtn = document.getElementById("logoutBtn");

// Dashboard elements
const userSearchInput = document.getElementById("userSearchInput");
const searchBtn = document.getElementById("searchBtn");
const searchStatus = document.getElementById("searchStatus");
const userResults = document.getElementById("userResults");
const dateFilter = document.getElementById("dateFilter");
const standupStatus = document.getElementById("standupStatus");
const standupList = document.getElementById("standupList");
const result = document.getElementById("result");

let selectedUser = null;
let currentStandups = [];
const standupState = new Map();

// --- Auth logic ---

function getAuthToken() {
  return localStorage.getItem("access_token") || "";
}

function setAuthToken(token) {
  if (token) {
    localStorage.setItem("access_token", token);
  } else {
    localStorage.removeItem("access_token");
  }
}

function checkAuth() {
  const token = getAuthToken();
  if (token) {
    loginPage.classList.add("hidden");
    dashboard.classList.remove("hidden");
  } else {
    loginPage.classList.remove("hidden");
    dashboard.classList.add("hidden");
  }
}

async function login() {
  let phone = phoneInput.value.trim();
  const password = passwordInput.value.trim();

  if (!phone || !password) {
    showError(loginError, "Please enter both phone and password.");
    return;
  }

  // Normalise phone: if user typed a plain 10-digit number, prepend +91
  if (/^\d{10}$/.test(phone)) {
    phone = "+91" + phone;
  } else if (/^91\d{10}$/.test(phone)) {
    // e.g. 919876543210 → +919876543210
    phone = "+" + phone;
  }

  setLoading(loginBtn, true, "Logging in...");
  hideError(loginError);

  try {
    const resp = await fetch(`${API_BASE}/auth/login`, {
      method: "POST",
      headers: { "Content-Type": "application/json", accept: "application/json" },
      body: JSON.stringify({ phone, password }),
    });

    if (!resp.ok) {
      const msg = await parseErrorResponse(resp);
      throw new Error(msg);
    }

    const data = await resp.json();
    if (data.access_token) {
      setAuthToken(data.access_token);
      checkAuth();
    } else {
      throw new Error("Invalid response from server.");
    }
  } catch (err) {
    showError(loginError, `Login failed: ${err.message}`);
  } finally {
    setLoading(loginBtn, false, "Login");
  }
}

function logout() {
  setAuthToken("");
  checkAuth();
}

// --- API helpers ---

function buildHeaders({ json = false } = {}) {
  const headers = { accept: "application/json" };
  const token = getAuthToken();
  if (token) headers.Authorization = `Bearer ${token}`;
  if (json) headers["Content-Type"] = "application/json";
  return headers;
}

async function parseErrorResponse(resp) {
  try {
    const body = await resp.json();
    if (typeof body?.detail === "string") return body.detail;
    if (Array.isArray(body?.detail)) {
      return body.detail.map((e) => e.msg || JSON.stringify(e)).join(", ");
    }
    if (typeof body?.message === "string") return body.message;
    return JSON.stringify(body);
  } catch (_) {
    return `${resp.status} ${resp.statusText}`;
  }
}

async function fetchJson(path, init = {}) {
  const resp = await fetch(`${API_BASE}${path}`, {
    ...init,
    headers: {
      ...buildHeaders({ json: init.body && typeof init.body === "string" }),
      ...(init.headers || {}),
    },
  });

  if (resp.status === 401) {
    logout();
    throw new Error("Session expired. Please login again.");
  }

  if (!resp.ok) {
    const msg = await parseErrorResponse(resp);
    throw new Error(msg);
  }

  return resp.json();
}

// --- UI helpers ---

function setLoading(btn, isLoading, text) {
  btn.disabled = isLoading;
  btn.textContent = text;
}

function showError(el, msg) {
  el.textContent = msg;
  el.classList.remove("hidden");
}

function hideError(el) {
  el.textContent = "";
  el.classList.add("hidden");
}

function formatDate(dateInput) {
  if (!dateInput) return "--";
  const d = new Date(dateInput);
  if (Number.isNaN(d.getTime())) return String(dateInput).slice(0, 10);
  return d.toISOString().slice(0, 10);
}

function userIdFromUser(user) {
  return user?.id || user?.user_id || user?.uid || "";
}

function usernameFromUser(user) {
  return user?.username || user?.user_name || user?.name || "Unknown";
}

function escapeHtml(value) {
  return String(value ?? "")
    .replace(/&/g, "&")
    .replace(/</g, "&lt;")
    .replace(/>/g, "&gt;")
    .replace(/\"/g, "&quot;")
    .replace(/'/g, "&#039;");
}

// --- Business logic ---

function renderUserResults(users) {
  userResults.innerHTML = "";

  if (!users.length) {
    userResults.innerHTML = '<p class="muted">No matching users found.</p>';
    return;
  }

  const frag = document.createDocumentFragment();
  users.forEach((user) => {
    const btn = document.createElement("button");
    btn.className = "item-btn";
    const username = usernameFromUser(user);
    btn.textContent = username;
    btn.addEventListener("click", () => onUserSelected(user));
    frag.appendChild(btn);
  });

  userResults.appendChild(frag);
}

function renderStandups(standups) {
  standupList.innerHTML = "";

  if (!standups.length) {
    standupList.innerHTML = '<p class="muted">No standups found.</p>';
    return;
  }

  const frag = document.createDocumentFragment();

  standups.forEach((item) => {
    const card = document.createElement("article");
    card.className = "standup-card";

    const hasAudio = Boolean(item.audio_url);
    const status = standupState.get(item.id) || {};

    card.innerHTML = `
      <div class="standup-head">Username: <strong>${escapeHtml(item.username)}</strong></div>
      <div>Date: ${escapeHtml(formatDate(item.date))}</div>
      <div>Status: <span class="pill ${escapeHtml(item.status?.toLowerCase())}">${escapeHtml(item.status || "Unknown")}</span></div>
      <div>Record ID: ${escapeHtml(item.id)}</div>
      ${hasAudio ? `<audio controls src="${escapeHtml(item.audio_url)}"></audio>` : '<p class="muted">Audio URL not available.</p>'}
      <button class="transcribe-action" ${hasAudio ? "" : "disabled"}>${status.loading ? "Transcribing..." : "Transcribe"}</button>
      ${status.error ? `<p class="error">${escapeHtml(status.error)}</p>` : ""}
      ${status.telugu ? `<div><strong>Telugu:</strong><pre>${escapeHtml(status.telugu)}</pre></div>` : ""}
    `;

    const actionBtn = card.querySelector(".transcribe-action");
    actionBtn?.addEventListener("click", () => transcribeStandup(item));

    frag.appendChild(card);
  });

  standupList.appendChild(frag);
}

async function searchUsers() {
  const query = userSearchInput.value.trim();
  if (!query) {
    searchStatus.textContent = "Enter username to search.";
    userResults.innerHTML = "";
    return;
  }

  setLoading(searchBtn, true, "Searching...");
  searchStatus.textContent = "Searching users...";

  try {
    const users = await fetchJson(`/users/search?query=${encodeURIComponent(query)}`);
    const filtered = (Array.isArray(users) ? users : []).filter((u) =>
      usernameFromUser(u).toLowerCase().includes(query.toLowerCase())
    );

    searchStatus.textContent = `Found ${filtered.length} matching user(s).`;
    renderUserResults(filtered);
  } catch (err) {
    searchStatus.textContent = `Search failed: ${err.message}`;
    userResults.innerHTML = "";
  } finally {
    setLoading(searchBtn, false, "Search");
  }
}

async function fetchAudioUrl(id) {
  try {
    const resp = await fetchJson(`/records/${id}/record-url?expires_minutes=60`);
    return resp?.record_url || null;
  } catch (_) {
    return null;
  }
}

async function enrichContribution(contribution, username) {
  const id = contribution?.id || contribution?.record_id || "";
  if (!id) return null;

  const timestamp = contribution?.timestamp || contribution?.created_at || contribution?.date || null;
  const audioUrl = await fetchAudioUrl(id);

  return {
    id,
    username,
    title: contribution?.title || "",
    date: timestamp,
    status: contribution?.status || "uploaded",
    audio_url: audioUrl,
  };
}

async function fetchStandupsForUser(user) {
  const username = usernameFromUser(user);
  const userId = userIdFromUser(user);
  const selectedDate = dateFilter.value; // e.g. "2024-03-20"

  if (!userId && !username) throw new Error("User ID not found");

  const identifier = userId || encodeURIComponent(username);

  standupStatus.textContent = `Loading standups for ${username}...`;
  standupList.innerHTML = "";

  try {
    const payload = await fetchJson(`/users/${identifier}/contributions/audio`);
    console.log('Fetched contributions payload:', payload);
    let rawContributions = Array.isArray(payload?.contributions)
      ? payload.contributions
      : Array.isArray(payload)
        ? payload
        : [];
    console.log('Extracted raw contributions count:', rawContributions.length);

    // Filter by selected date using the contribution's timestamp
    if (selectedDate) {
      rawContributions = rawContributions.filter((item) => {
        const ts = item?.timestamp || item?.created_at || item?.date || "";
        return ts.startsWith(selectedDate);
      });
      console.log('After date filter, count:', rawContributions.length);
    }

    if (rawContributions.length === 0) {
      standupStatus.textContent = selectedDate
        ? `No standups found for ${username} on ${selectedDate}.`
        : `No standups found for ${username}.`;
      renderStandups([]);
      return;
    }

    const limited = rawContributions.slice(0, 15);
    standupStatus.textContent = `Loading audio URLs for ${limited.length} standup(s)...`;

    const enriched = (await Promise.all(
      limited.map((item) => enrichContribution(item, username))
    )).filter(Boolean);

    standupStatus.textContent = `Loaded ${enriched.length} standup(s) for ${username}${selectedDate ? " on " + selectedDate : ""}.`;
    currentStandups = enriched;
    renderStandups(currentStandups);
  } catch (err) {
    standupStatus.textContent = `Failed to load standups: ${err.message}`;
    renderStandups([]);
  }
}

async function onUserSelected(user) {
  selectedUser = user;
  standupState.clear();
  await fetchStandupsForUser(user);
}

async function transcribeAudio(audioUrl) {
  // Send the URL to the local backend which fetches & transcribes server-side.
  // This avoids CORS errors that occur when the browser tries to fetch
  // the audio directly from the Corpus CDN.
  let resp;
  try {
    resp = await fetch(`${LOCAL_ASR_BASE}/transcribe-url`, {
      method: "POST",
      headers: { "Content-Type": "application/json" },
      body: JSON.stringify({ audio_url: audioUrl }),
    });
  } catch (networkErr) {
    // fetch() itself threw — backend is not reachable at all
    throw new Error(
      `Cannot reach ASR backend at ${LOCAL_ASR_BASE}. Is the backend running? (${networkErr.message})`
    );
  }

  // Log for debugging
  console.log("[ASR] response status:", resp.status, resp.statusText);
  console.log("[ASR] content-type:", resp.headers.get("content-type"));

  if (resp.status === 404) {
    throw new Error(
      `ASR endpoint not found (404). Backend may be on a different port. Check LOCAL_ASR_BASE_URL in config.js (currently: ${LOCAL_ASR_BASE})`
    );
  }

  if (!resp.ok) {
    // Try to get a meaningful JSON detail from the backend error
    let detail = `${resp.status} ${resp.statusText}`;
    try {
      const body = await resp.json();
      if (body?.detail) {
        detail = typeof body.detail === "string" ? body.detail : JSON.stringify(body.detail);
      }
    } catch (_) { /* non-JSON error body */ }
    throw new Error(detail);
  }

  const data = await resp.json();
  return data?.text || null;
}

async function transcribeStandup(item) {
  const state = standupState.get(item.id) || {};
  standupState.set(item.id, { ...state, loading: true, error: "" });
  renderStandups(currentStandups);

  try {
    const telugu = await transcribeAudio(item.audio_url);
    if (!telugu) throw new Error("No transcription returned.");

    standupState.set(item.id, {
      loading: false,
      telugu,
      error: "",
    });
    result.textContent = `Telugu Transcript (ID ${item.id}):\n${telugu}`;
  } catch (err) {
    standupState.set(item.id, {
      loading: false,
      error: err.message,
    });
    result.textContent = `Transcription failed: ${err.message}`;
  }

  renderStandups(currentStandups);
}

// --- Listeners ---

loginBtn.addEventListener("click", login);
logoutBtn.addEventListener("click", logout);
searchBtn.addEventListener("click", searchUsers);
userSearchInput.addEventListener("keydown", (e) => {
  if (e.key === "Enter") searchUsers();
});

dateFilter.addEventListener('change', () => {
  if (selectedUser) {
    // Re-fetch standups for the currently selected user with new date filter
    fetchStandupsForUser(selectedUser);
  }
});

// Init
checkAuth();