research-workbench/frontend/src/components/LoginPage.tsx

import { useState } from 'react'
import type { FormEvent } from 'react'

interface LoginPageProps {
  onLogin: (email: string, password: string) => Promise<void>
}

export function LoginPage({ onLogin }: LoginPageProps) {
  const [email, setEmail] = useState('')
  const [password, setPassword] = useState('')
  const [error, setError] = useState('')
  const [loading, setLoading] = useState(false)

  async function handleSubmit(e: FormEvent) {
    e.preventDefault()
    setError('')
    setLoading(true)
    try {
      await onLogin(email, password)
    } catch {
      setError('Invalid credentials')
    } finally {
      setLoading(false)
    }
  }

  return (
    <div className="login-page">
      <form className="login-card" onSubmit={handleSubmit}>
        <h2>Research Workbench</h2>
        {error && <div className="error">{error}</div>}
        <label htmlFor="email">Email</label>
        <input
          id="email"
          type="email"
          value={email}
          onChange={e => setEmail(e.target.value)}
          autoFocus
          required
        />
        <label htmlFor="password">Password</label>
        <input
          id="password"
          type="password"
          value={password}
          onChange={e => setPassword(e.target.value)}
          required
        />
        <button type="submit" disabled={loading}>
          {loading ? 'Signing in...' : 'Sign In'}
        </button>
      </form>
    </div>
  )
}