SPARC/frontend/src/components/Layout.tsx

import { Outlet, NavLink, useNavigate } from 'react-router-dom';
import { useAuth } from '../context/AuthContext';
import { useTheme } from '../context/ThemeContext';
import { Search, Layers, BarChart3, Info, Users, LogOut, GitCompareArrows, Sun, Moon } from 'lucide-react';

export function Layout() {
  const { user, isAdmin, logout } = useAuth();
  const { theme, toggleTheme } = useTheme();
  const navigate = useNavigate();

  const handleLogout = () => {
    logout();
    navigate('/login');
  };

  const navItems = [
    { to: '/analysis', icon: Search, label: 'Analysis' },
    { to: '/batch', icon: Layers, label: 'Batch' },
    { to: '/analytics', icon: BarChart3, label: 'Analytics' },
    { to: '/compare', icon: GitCompareArrows, label: 'Compare' },
    { to: '/about', icon: Info, label: 'About' },
  ];

  if (isAdmin) {
    navItems.push({ to: '/admin/users', icon: Users, label: 'Users' });
  }

  return (
    <div className="min-h-screen bg-gradient-to-br from-bg-dark to-slate-100 dark:to-indigo-950">
      {/* Header */}
      <header className="bg-bg-card/80 backdrop-blur-lg border-b border-primary/20">
        <div className="max-w-7xl mx-auto px-4 sm:px-6 lg:px-8">
          <div className="flex items-center justify-between h-16">
            {/* Brand */}
            <div className="flex items-center gap-3">
              <span className="text-2xl">⚡</span>
              <div>
                <h1 className="text-xl font-bold bg-gradient-to-r from-primary to-secondary bg-clip-text text-transparent">
                  SPARC
                </h1>
                <span className="text-xs text-text-secondary uppercase tracking-wider">
                  Semiconductor Patent Analytics
                </span>
              </div>
            </div>

            {/* Navigation */}
            <nav className="hidden md:flex items-center gap-1 bg-bg-card/60 rounded-xl p-1 border border-primary/15">
              {navItems.map(({ to, icon: Icon, label }) => (
                <NavLink
                  key={to}
                  to={to}
                  className={({ isActive }) =>
                    `flex items-center gap-2 px-4 py-2 rounded-lg text-sm font-medium transition-all ${
                      isActive
                        ? 'bg-gradient-to-r from-primary to-primary-dark text-white'
                        : 'text-text-secondary hover:text-text-primary hover:bg-bg-card-hover'
                    }`
                  }
                >
                  <Icon size={16} />
                  {label}
                </NavLink>
              ))}
            </nav>

            {/* User menu */}
            <div className="flex items-center gap-4">
              <button
                onClick={toggleTheme}
                className="p-2 rounded-lg text-text-secondary hover:text-text-primary hover:bg-bg-card-hover transition-all"
                aria-label={theme === 'dark' ? 'Switch to light mode' : 'Switch to dark mode'}
              >
                {theme === 'dark' ? <Sun size={18} /> : <Moon size={18} />}
              </button>
              <div className="text-right hidden sm:block">
                <div className="text-sm font-medium text-text-primary">{user?.email}</div>
                <div className="text-xs text-text-secondary capitalize">{user?.role}</div>
              </div>
              <button
                onClick={handleLogout}
                className="flex items-center gap-2 px-3 py-2 rounded-lg text-text-secondary hover:text-error hover:bg-error/10 transition-all"
              >
                <LogOut size={18} />
                <span className="hidden sm:inline">Logout</span>
              </button>
            </div>
          </div>
        </div>
      </header>

      {/* Mobile Navigation */}
      <nav className="md:hidden fixed bottom-0 left-0 right-0 bg-bg-card/95 backdrop-blur-lg border-t border-primary/20 z-50">
        <div className="flex justify-around py-2">
          {navItems.map(({ to, icon: Icon, label }) => (
            <NavLink
              key={to}
              to={to}
              className={({ isActive }) =>
                `flex flex-col items-center gap-1 px-3 py-2 rounded-lg text-xs font-medium transition-all ${
                  isActive ? 'text-primary' : 'text-text-secondary'
                }`
              }
            >
              <Icon size={20} />
              {label}
            </NavLink>
          ))}
        </div>
      </nav>

      {/* Main content */}
      <main className="max-w-7xl mx-auto px-4 sm:px-6 lg:px-8 py-8 pb-24 md:pb-8">
        <Outlet />
      </main>
    </div>
  );
}