/**
 * MainLayout
 *
 * Hauptlayout der Anwendung mit Sidebar und Content-Bereich.
 * Enthält den FeatureProvider für das Multi-Tenant-System.
 */

import React, { useEffect, useRef, useState } from 'react';
import { Outlet, useLocation } from 'react-router-dom';
import { FeatureProvider, useFeatureStore } from '../stores/featureStore';
import { MandateNavigation } from '../components/Navigation/MandateNavigation';
import { UserSection } from '../components/Navigation/UserSection';
import { RagRunningBadge } from '../components/RagRunningBadge/RagRunningBadge';
import { KEEP_ALIVE_ROUTES, hideFeatureOutlet } from '../config/keepAliveRoutes';
import type { KeepAliveEntry, KeepAliveScopedEntry, KeepAliveUnscopedEntry } from '../types/keepAlive.types';
import { isKeepAliveScoped } from '../types/keepAlive.types';
import styles from './MainLayout.module.css';

import { useLanguage } from '../providers/language/LanguageContext';

const keepAliveShellStyle = (isVisible: boolean, shellOverflowHidden: boolean): React.CSSProperties => ({
  display: isVisible ? 'flex' : 'none',
  flexDirection: 'column',
  position: 'absolute',
  top: 'var(--mobile-topbar-height, 0px)',
  left: 0,
  right: 0,
  bottom: 0,
  ...(shellOverflowHidden ? { overflow: 'hidden' as const } : {}),
});

const RoutedKeepAliveUnscoped: React.FC<{ entry: KeepAliveUnscopedEntry; pathname: string }> = ({
  entry,
  pathname,
}) => {
  const isVisible = entry.pathRegex.test(pathname);
  return (
    <div style={keepAliveShellStyle(isVisible, true)}>
      {entry.render()}
    </div>
  );
};

const RoutedKeepAliveScoped: React.FC<{ entry: KeepAliveScopedEntry; pathname: string }> = ({
  entry,
  pathname,
}) => {
  const isVisible = entry.pathRegex.test(pathname);
  const {
    scopeRegex,
    requireMandateForMount = true,
    shellOverflowHidden = true,
    render,
  } = entry;

  const cachedMandateIdRef = useRef<string>('');
  const cachedInstanceIdRef = useRef<string>('');

  const match = pathname.match(scopeRegex);
  if (match?.[1] && match?.[2]) {
    cachedMandateIdRef.current = match[1];
    cachedInstanceIdRef.current = match[2];
  }

  const mandateId = cachedMandateIdRef.current;
  const instanceId = cachedInstanceIdRef.current;

  const scopeReady = requireMandateForMount
    ? !!(mandateId && instanceId)
    : !!instanceId;

  if (!scopeReady) {
    return null;
  }

  const scopeKey = `${mandateId}:${instanceId}`;

  return (
    <div style={keepAliveShellStyle(isVisible, shellOverflowHidden)}>
      {render({ mandateId, instanceId, scopeKey })}
    </div>
  );
};

const RoutedKeepAliveSlot: React.FC<{ entry: KeepAliveEntry; pathname: string }> = ({
  entry,
  pathname,
}) => {
  if (!isKeepAliveScoped(entry)) {
    return <RoutedKeepAliveUnscoped entry={entry} pathname={pathname} />;
  }
  return <RoutedKeepAliveScoped entry={entry} pathname={pathname} />;
};

// =============================================================================
// INNER LAYOUT (mit Zugriff auf Store)
// =============================================================================

const MainLayoutInner: React.FC = () => {
  const { t } = useLanguage();

  const { loadFeatures, initialized, loading, error } = useFeatureStore();
  const location = useLocation();
  const [isMobileSidebarOpen, setIsMobileSidebarOpen] = useState(false);
  const hideOutletShell = hideFeatureOutlet(location.pathname);

  // Features laden beim Mount
  useEffect(() => {
    if (!initialized && !loading) {
      loadFeatures();
    }
  }, [initialized, loading, loadFeatures]);

  useEffect(() => {
    setIsMobileSidebarOpen(false);
  }, [location.pathname]);

  useEffect(() => {
    const handleResize = () => {
      if (window.innerWidth > 1024) {
        setIsMobileSidebarOpen(false);
      }
    };

    window.addEventListener('resize', handleResize);
    return () => window.removeEventListener('resize', handleResize);
  }, []);

  return (
    <div className={styles.mainLayout}>
      {isMobileSidebarOpen && (
        <button
          className={styles.mobileBackdrop}
          onClick={() => setIsMobileSidebarOpen(false)}
          aria-label={t('Navigation schließen')}
        />
      )}

      {/* Sidebar */}
      <aside className={`${styles.sidebar} ${isMobileSidebarOpen ? styles.sidebarOpen : ''}`}>
        <div className={styles.logoContainer}>
          <img src="/logos/poweron-logo.png" alt="PowerOn" className={styles.logoImage} />
        </div>

        <nav className={styles.navigation}>
          {loading && <div className={styles.loadingNav}>{t('Lade Navigation…')}</div>}

          {error && (
            <div className={styles.errorNav}>
              {t('Fehler')}: {error}
            </div>
          )}

          {initialized && !loading && <MandateNavigation />}
        </nav>

        {/* User-Bereich am unteren Rand */}
        <UserSection />
      </aside>

      {/* Content */}
      <main className={styles.content}>
        <div className={styles.mobileTopBar}>
          <button
            className={styles.mobileMenuButton}
            onClick={() => setIsMobileSidebarOpen(true)}
            aria-label={t('Navigation öffnen')}
          >
            ☰
          </button>
          <img src="/logos/poweron-logo.png" alt="PowerOn" className={styles.mobileLogo} />
        </div>

        {KEEP_ALIVE_ROUTES.map((routeEntry) => (
          <RoutedKeepAliveSlot key={routeEntry.id} entry={routeEntry} pathname={location.pathname} />
        ))}

        <div
          className={styles.outletShell}
          style={{ display: hideOutletShell ? 'none' : undefined }}
        >
          <Outlet />
        </div>
      </main>

      <RagRunningBadge />
    </div>
  );
};

// =============================================================================
// MAIN LAYOUT (mit Provider)
// =============================================================================

export const MainLayout: React.FC = () => {
  return (
    <FeatureProvider>
      <MainLayoutInner />
    </FeatureProvider>
  );
};

export default MainLayout;