client/src/components/UI/AuthDialog.jsx

import { useState } from 'react'
import { Globe, Loader2 } from 'lucide-react'
import Modal from './Modal'
import Button from './Button'

export default function AuthDialog({
  open,
  mode,
  onModeChange,
  onClose,
  onLogin,
  onRegister,
  onGoogleLogin,
  pending,
}) {
  const [username, setUsername] = useState('')
  const [password, setPassword] = useState('')
  const [error, setError] = useState('')

  const submit = async (event) => {
    event.preventDefault()
    setError('')

    if (!username || !password) {
      setError('Please fill in both fields.')
      return
    }

    try {
      if (mode === 'register') {
        await onRegister({ username, password })
      } else {
        await onLogin({ username, password })
      }
    } catch (authError) {
      setError(authError.message || 'Authentication failed.')
    }
  }

  return (
    <Modal
      open={open}
      onOpenChange={(next) => {
        if (!next) onClose()
      }}
      size="sm"
      title={mode === 'register' ? 'Create your OwnGPT account' : 'Sign in to OwnGPT'}
      description="Sync your sessions, upload files, and unlock the full workspace."
    >
      <div className="space-y-5">
        <div className="grid grid-cols-2 gap-2 rounded-2xl bg-panel p-1">
          <button
            type="button"
            onClick={() => onModeChange('login')}
            className={`rounded-2xl px-4 py-2 text-sm font-medium transition ${
              mode === 'login'
                ? 'bg-background text-foreground shadow-soft'
                : 'text-muted-foreground hover:text-foreground'
            }`}
          >
            Sign in
          </button>
          <button
            type="button"
            onClick={() => onModeChange('register')}
            className={`rounded-2xl px-4 py-2 text-sm font-medium transition ${
              mode === 'register'
                ? 'bg-background text-foreground shadow-soft'
                : 'text-muted-foreground hover:text-foreground'
            }`}
          >
            Register
          </button>
        </div>

        <form className="space-y-4" onSubmit={submit}>
          <label className="block space-y-2">
            <span className="text-sm font-medium text-foreground">Username</span>
            <input
              className="w-full rounded-2xl border border-input bg-panel px-4 py-3 text-sm text-foreground outline-none transition placeholder:text-muted-foreground focus:border-accent/50 focus:ring-2 focus:ring-ring/20"
              value={username}
              onChange={(event) => setUsername(event.target.value)}
              placeholder={mode === 'register' ? 'letters, numbers, underscores' : 'your username'}
              autoFocus
            />
          </label>
          <label className="block space-y-2">
            <span className="text-sm font-medium text-foreground">Password</span>
            <input
              type="password"
              className="w-full rounded-2xl border border-input bg-panel px-4 py-3 text-sm text-foreground outline-none transition placeholder:text-muted-foreground focus:border-accent/50 focus:ring-2 focus:ring-ring/20"
              value={password}
              onChange={(event) => setPassword(event.target.value)}
              placeholder="••••••••"
            />
          </label>
          {error ? <p className="text-sm text-danger">{error}</p> : null}
          <Button type="submit" variant="primary" className="w-full" loading={pending}>
            {pending ? <Loader2 className="h-4 w-4 animate-spin" /> : null}
            {mode === 'register' ? 'Create account' : 'Sign in'}
          </Button>
        </form>

        <div className="relative">
          <div className="absolute inset-0 flex items-center">
            <div className="h-px w-full bg-border/80" />
          </div>
          <div className="relative flex justify-center">
            <span className="bg-card px-3 text-xs uppercase tracking-[0.16em] text-muted-foreground">
              Or continue with
            </span>
          </div>
        </div>

        <Button variant="secondary" className="w-full" onClick={onGoogleLogin}>
          <Globe className="h-4 w-4" />
          Google
        </Button>
      </div>
    </Modal>
  )
}