import { renderHeader } from '../components/header.js';
import { directMessages } from '../mock-data.js';
import {
  addAppLogEntry,
  addSystemChatMessage,
  addOutgoingPendingMessage,
  getChatMessages,
  markChatRead,
  markOutgoingSent,
  markReadReceiptSentByBaseKey,
  authService,
  state,
} from '../state.js';
import { startOutgoingCall } from '../services/call-service.js';

export const pageMeta = { id: 'chat-view', title: 'Чат' };

function parseBaseKey(baseKey) {
  const raw = String(baseKey || '').trim();
  const parts = raw.split('|');
  if (parts.length < 4) return null;
  const fromLogin = parts[0] || '';
  const toLogin = parts[1] || '';
  const timeMs = Number(parts[2] || 0);
  const nonce = Number(parts[3] || 0);
  if (!fromLogin || !toLogin || !Number.isFinite(timeMs) || !Number.isFinite(nonce)) return null;
  return { fromLogin, toLogin, timeMs, nonce };
}

function resolveMessageTimeMs(msg) {
  const base = parseBaseKey(msg?.baseKey);
  if (base?.timeMs && Number.isFinite(base.timeMs) && base.timeMs > 0) return base.timeMs;

  const messageKey = String(msg?.messageKey || '').trim();
  if (messageKey) {
    const parts = messageKey.split('|');
    const timeMs = Number(parts[2] || 0);
    if (parts.length >= 4 && Number.isFinite(timeMs) && timeMs > 0) return timeMs;
  }

  const tempId = String(msg?.tempId || '').trim();
  if (tempId.startsWith('tmp-')) {
    const ts = Number(tempId.split('-')[1] || 0);
    if (Number.isFinite(ts) && ts > 0) return ts;
  }

  const fallback = Number(msg?.createdAtMs || 0);
  if (Number.isFinite(fallback) && fallback > 0) return fallback;
  return 0;
}

function formatMessageTime(valueMs) {
  const timeMs = Number(valueMs || 0);
  if (!Number.isFinite(timeMs) || timeMs <= 0) return '';
  return new Intl.DateTimeFormat('ru-RU', {
    day: '2-digit',
    month: '2-digit',
    year: '2-digit',
    hour: '2-digit',
    minute: '2-digit',
  }).format(new Date(timeMs));
}

function resolveDeliveryStatus(msg) {
  if (msg?.from !== 'out') return '';
  if (msg?.secondTick) return '✓✓';
  if (msg?.firstTick) return '✓';
  return '…';
}

function renderLog(list, chatId) {
  list.innerHTML = '';
  const messages = getChatMessages(chatId);
  let unreadSeparatorInserted = false;
  messages.forEach((msg) => {
    if (!unreadSeparatorInserted && msg?.from === 'in' && msg?.unread) {
      const sep = document.createElement('div');
      sep.className = 'chat-unread-separator';
      const label = document.createElement('span');
      label.textContent = 'Новые сообщения';
      sep.append(label);
      list.append(sep);
      unreadSeparatorInserted = true;
    }

    const bubble = document.createElement('div');
    const bubbleKind = String(msg?.kind || '').trim();
    bubble.className = `bubble ${msg.from}${bubbleKind ? ` ${bubbleKind}` : ''}`;

    const textNode = document.createElement('div');
    textNode.className = 'bubble-text';
    textNode.textContent = msg.text || '';

    const metaNode = document.createElement('div');
    metaNode.className = 'bubble-meta';

    const timeNode = document.createElement('span');
    timeNode.className = 'bubble-time';
    timeNode.textContent = formatMessageTime(resolveMessageTimeMs(msg));
    metaNode.append(timeNode);

    const status = resolveDeliveryStatus(msg);
    if (status) {
      const statusNode = document.createElement('span');
      statusNode.className = 'bubble-status';
      statusNode.textContent = status;
      metaNode.append(statusNode);
    }

    bubble.append(textNode, metaNode);
    list.append(bubble);
  });
  list.scrollTop = list.scrollHeight;
  markChatRead(chatId);
}

export function render({ navigate, route }) {
  const chatId = route.params.chatId || 'u1';
  const contact = directMessages.find((d) => d.id === chatId) || {
    id: chatId,
    name: chatId,
    initials: (chatId[0] || '?').toUpperCase(),
  };

  const screen = document.createElement('section');
  screen.className = 'stack';
  const isKnownContact = (state.contacts || []).some((x) => String(x || '').toLowerCase() === String(chatId || '').toLowerCase());

  screen.append(
    renderHeader({
      title: `Чат: ${contact.name}`,
      leftAction: { label: '←', onClick: () => navigate('messages-list') },
      rightActions: [{
        label: 'Позвонить',
        onClick: async () => {
          try {
            await startOutgoingCall(chatId);
            renderLog(log, chatId);
          } catch (e) {
            addSystemChatMessage(chatId, `[Звонок] Ошибка запуска: ${e.message || 'unknown'}`, {
              from: 'out',
              kind: 'call-tech',
            });
            renderLog(log, chatId);
          }
        },
      }],
    })
  );

  if (!isKnownContact) {
    const card = document.createElement('div');
    card.className = 'card';
    const btn = document.createElement('button');
    btn.className = 'secondary-btn';
    btn.type = 'button';
    btn.textContent = 'Добавить в контакты';
    btn.addEventListener('click', async () => {
      try {
        await authService.addCloseFriend(chatId);
        state.contacts = [...new Set([...(state.contacts || []), chatId])];
        addAppLogEntry({
          level: 'info',
          source: 'contacts',
          message: `Пользователь ${chatId} добавлен в контакты`,
        });
        btn.disabled = true;
        btn.textContent = 'Добавлено';
      } catch (e) {
        addAppLogEntry({
          level: 'warn',
          source: 'contacts',
          message: 'Не удалось добавить пользователя в контакты',
          details: { login: chatId, error: e?.message || 'unknown' },
        });
      }
    });
    card.append(btn);
    screen.append(card);
  }

  const wrap = document.createElement('div');
  wrap.className = 'chat-wrap';

  const log = document.createElement('div');
  log.className = 'messages-log';

  const form = document.createElement('form');
  form.className = 'chat-input';
  form.innerHTML = `
    <input class="input" type="text" name="message" placeholder="Введите сообщение" maxlength="300" />
    <button class="primary-btn" type="submit">Отправить</button>
  `;

  form.addEventListener('submit', async (event) => {
    event.preventDefault();
    const input = form.elements.message;
    const text = input.value.trim();
    if (!text) return;

    const tempId = addOutgoingPendingMessage(chatId, text);
    input.value = '';
    renderLog(log, chatId);

    try {
      const result = await authService.sendDirectMessage({
        login: state.session.login,
        toLogin: chatId,
        text,
        storagePwd: state.session.storagePwdInMemory,
      });
      markOutgoingSent(tempId, {
        messageKey: result?.outgoingKey || '',
        baseKey: result?.baseKey || result?.localBaseKey || '',
      });
      renderLog(log, chatId);
      addAppLogEntry({
        level: 'info',
        source: 'outgoing-dm',
        message: `Сообщение отправлено для ${chatId}`,
        details: {
          toLogin: chatId,
          messageId: result?.outgoingKey || '',
          deliveredWsSessions: Number(result?.deliveredWsSessions || 0),
          deliveredWebPushSessions: Number(result?.deliveredWebPushSessions || 0),
        },
      });
    } catch (e) {
      addChatMessage(chatId, `Ошибка отправки: ${e.message || 'unknown'}`);
      addAppLogEntry({
        level: 'warn',
        source: 'outgoing-dm',
        message: 'Ошибка отправки личного сообщения',
        details: {
          toLogin: chatId,
          error: e?.message || 'unknown',
        },
      });
      renderLog(log, chatId);
    }
  });

  renderLog(log, chatId);
  void sendReadReceiptsForVisible(chatId);
  wrap.append(log, form);
  screen.append(wrap);
  return screen;
}
async function sendReadReceiptsForVisible(chatId) {
  const pending = getChatMessages(chatId)
      .filter((row) => row?.from === 'in' && Number(row?.messageType) === 1 && !row?.readReceiptSent)
      .slice(0, 50);
  for (const row of pending) {
    const ref = parseBaseKey(row.baseKey);
    if (!ref) continue;
    try {
      await authService.sendReadReceipt({
        login: state.session.login,
        toLogin: ref.fromLogin,
        storagePwd: state.session.storagePwdInMemory,
        refToLogin: ref.toLogin,
        refFromLogin: ref.fromLogin,
        refTimeMs: ref.timeMs,
        refNonce: ref.nonce,
        refType: 1,
      });
      if (row.baseKey) {
        markReadReceiptSentByBaseKey(row.baseKey);
      } else {
        row.readReceiptSent = true;
      }
    } catch (e) {
      addAppLogEntry({
        level: 'warn',
        source: 'read-receipt',
        message: 'Не удалось отправить подтверждение прочтения',
        details: { chatId, messageKey: row.messageKey || '', error: e?.message || 'unknown' },
      });
    }
  }
}