import { createTopBar } from '../components/topbar.js';
import {
  authorizeLocalDemoSession,
  isLocalDemoAvailable,
  saveEntrySettings,
  state,
} from '../state.js';
import { checkServerAvailabilityByKey, resolveAndCheckShineServerLogin } from '../services/server-health-service.js';

export const pageMeta = { id: 'entry-settings-view', title: 'Настройки входа', showAppChrome: false };

const SERVER_FIELDS = [
  { key: 'solanaServer', label: 'Сервер Solana' },
  { key: 'shineServerLogin', label: 'Сервер Сияния' },
  { key: 'arweaveServer', label: 'Сервер Arweave' },
];

export function render({ navigate }) {
  const screen = document.createElement('section');
  screen.className = 'stack entry-settings';

  const draft = {
    language: state.entrySettings.language,
    solanaServer: state.entrySettings.solanaServer,
    shineServerLogin: state.entrySettings.shineServerLogin,
    shineServerHttp: state.entrySettings.shineServerHttp,
    arweaveServer: state.entrySettings.arweaveServer,
    statuses: { ...state.entrySettings.statuses },
  };

  const timers = new Map();

  let disposed = false;
  const checks = [];

  const body = document.createElement('div');
  body.className = 'entry-servers';

  SERVER_FIELDS.forEach((field) => {
    const block = document.createElement('div');
    block.className = 'entry-server';

    const head = document.createElement('div');
    head.className = 'entry-server__head';

    const title = document.createElement('label');
    title.className = 'field-label';
    title.htmlFor = `entry-${field.key}`;
    title.textContent = field.label;

    // Статус — он же кнопка повторной проверки.
    const checkButton = document.createElement('button');
    checkButton.className = 'text-btn entry-status';
    checkButton.type = 'button';

    const input = document.createElement('input');
    input.className = 'input';
    input.id = `entry-${field.key}`;
    input.type = 'text';
    input.autocapitalize = 'off';
    input.spellcheck = false;
    input.value = draft[field.key];

    const hint = document.createElement('p');
    hint.className = 'entry-server__hint';

    const applyStatus = (value, exactAddress = '') => {
      if (disposed) return;
      if (value !== 'checking') draft.statuses[field.key] = value;
      checkButton.classList.remove('is-available', 'is-unavailable', 'is-checking');
      checkButton.disabled = false;

      if (value === 'available') {
        checkButton.textContent = 'Доступен';
        checkButton.classList.add('is-available');
      } else if (value === 'unavailable') {
        checkButton.textContent = 'Недоступен';
        checkButton.classList.add('is-unavailable');
      } else if (value === 'checking') {
        checkButton.textContent = 'Проверка…';
        checkButton.classList.add('is-checking');
        checkButton.disabled = true;
      } else {
        checkButton.textContent = 'Проверить';
      }
      checkButton.setAttribute('aria-label', `${field.label}: ${checkButton.textContent}. Проверить ещё раз`);

      if (field.key === 'shineServerLogin') {
        const address = exactAddress || draft.shineServerHttp;
        hint.textContent = address || '';
        hint.hidden = !address;
      }
    };

    let checkSeq = 0;
    const runCheck = async () => {
      draft[field.key] = input.value.trim();
      window.clearTimeout(timers.get(field.key));
      // Результат устаревшей проверки (адрес успели поменять) не должен перезаписать новый.
      const seq = ++checkSeq;
      applyStatus('checking');
      try {
        if (field.key === 'shineServerLogin') {
          const resolved = await resolveAndCheckShineServerLogin(input.value, draft.solanaServer);
          if (seq !== checkSeq) return;
          draft.shineServerHttp = resolved.httpBase;
          draft.shineServer = resolved.wsUrl;
          applyStatus(resolved.status, resolved.httpBase);
        } else {
          const next = await checkServerAvailabilityByKey(field.key, input.value, {
            solanaEndpoint: draft.solanaServer,
          });
          if (seq !== checkSeq) return;
          applyStatus(next);
        }
      } catch {
        if (seq === checkSeq) applyStatus('unavailable');
      }
    };

    applyStatus(draft.statuses[field.key]);
    hint.hidden = field.key !== 'shineServerLogin' || !hint.textContent;
    checks.push(runCheck);

    checkButton.addEventListener('click', runCheck);
    input.addEventListener('input', () => {
      draft[field.key] = input.value;
      checkSeq += 1;
      applyStatus('idle');
      window.clearTimeout(timers.get(field.key));
      timers.set(field.key, window.setTimeout(() => {
        void runCheck();
      }, 3000));
    });
    input.addEventListener('change', () => {
      void runCheck();
    });
    input.addEventListener('keydown', (event) => {
      if (event.key === 'Enter') {
        event.preventDefault();
        void runCheck();
      }
    });

    head.append(title, checkButton);
    block.append(head, input, hint);
    body.append(block);
  });

  const actions = document.createElement('div');
  actions.className = 'entry-settings__actions';

  if (isLocalDemoAvailable()) {
    const localDemoButton = document.createElement('button');
    localDemoButton.className = 'secondary-btn';
    localDemoButton.type = 'button';
    localDemoButton.textContent = 'Открыть локальный тестовый режим';
    localDemoButton.addEventListener('click', () => {
      if (!authorizeLocalDemoSession()) return;
      navigate('messages-list');
    });
    actions.append(localDemoButton);
  }

  const serverUiButton = document.createElement('button');
  serverUiButton.className = 'secondary-btn';
  serverUiButton.type = 'button';
  serverUiButton.textContent = 'Настроить свой сервер ↗';
  serverUiButton.addEventListener('click', () => {
    const url = new URL('server-ui.html', window.location.href);
    window.open(url.toString(), '_blank', 'noopener');
  });

  const saveButton = document.createElement('button');
  saveButton.className = 'primary-btn';
  saveButton.type = 'button';
  saveButton.textContent = 'Сохранить';
  saveButton.addEventListener('click', async () => {
    try {
      await saveEntrySettings(draft);
      navigate('start-view');
    } catch (error) {
      window.alert(error?.message || 'Не удалось сохранить настройки входа.');
    }
  });

  actions.prepend(saveButton);
  actions.append(serverUiButton);

  screen.append(
    createTopBar({
      title: 'Настройки входа',
      back: { label: '←', onClick: () => navigate('start-view') },
    }),
    body,
    actions,
  );

  screen.cleanup = () => {
    disposed = true;
    timers.forEach((timerId) => window.clearTimeout(timerId));
  };

  // Серверы проверяются сразу — зелёный «Доступен» видно без лишних нажатий.
  checks.forEach((check) => { void check(); });

  return screen;
}