import { FormEvent, useState } from 'react'
import { api } from './api'
import { Spinner } from './ui'

// Drawn, not typed: 👁 is an emoji on phones, full colour and its own size. Outline strokes
// match the glyphs in the rail and the power button.
const EyeIcon = (
  <svg viewBox="0 0 16 16" width="17" height="17" fill="none" stroke="currentColor" strokeWidth="1.4" strokeLinecap="round" strokeLinejoin="round" aria-hidden="true">
    <path d="M1.2 8S3.9 3.6 8 3.6 14.8 8 14.8 8 12.1 12.4 8 12.4 1.2 8 1.2 8z" /><circle cx="8" cy="8" r="2.1" />
  </svg>
)
const EyeOffIcon = (
  <svg viewBox="0 0 16 16" width="17" height="17" fill="none" stroke="currentColor" strokeWidth="1.4" strokeLinecap="round" strokeLinejoin="round" aria-hidden="true">
    <path d="M1.2 8S3.9 3.6 8 3.6 14.8 8 14.8 8 12.1 12.4 8 12.4 1.2 8 1.2 8z" /><circle cx="8" cy="8" r="2.1" /><path d="M2.4 13.6 13.6 2.4" />
  </svg>
)

const USER_KEY = 'hamlab.user' // the last account signed in on this device, offered again

export default function Login({ onLogin }: { onLogin: () => void }) {
  const [user, setUser] = useState(localStorage.getItem(USER_KEY) ?? '')
  const [pw, setPw] = useState('')
  const [err, setErr] = useState('')
  const [busy, setBusy] = useState(false)
  // Shown on request: a generated password is typed by hand off a message, and a wrong
  // character looks exactly like a wrong password from here.
  const [show, setShow] = useState(false)

  async function submit(e: FormEvent) {
    e.preventDefault()
    setBusy(true); setErr('')
    try {
      const r = await api.login(user.trim(), pw)
      localStorage.setItem(USER_KEY, r?.user ?? user.trim())
      onLogin()
    } catch (e) { setErr((e instanceof Error && e.message) || 'login failed'); setBusy(false) }
  }

  return (
    <div className="center">
      <form className="login" onSubmit={submit}>
        <img className="login-logo" src="/icons/logo.png" alt="Ham Lab" width={176} height={176} />
        <input type="text" autoFocus={!user} autoComplete="username" placeholder="user" spellCheck={false} autoCapitalize="off" autoCorrect="off"
          value={user} onChange={(e) => setUser(e.target.value)} disabled={busy} />
        <div className="pwfield">
          {/* revealed, the field is a text field, so the keyboard would otherwise offer to
              capitalise and correct what is typed into it */}
          <input type={show ? 'text' : 'password'} autoFocus={!!user} autoComplete="current-password" placeholder="password"
            spellCheck={false} autoCapitalize="off" autoCorrect="off"
            value={pw} onChange={(e) => setPw(e.target.value)} disabled={busy} />
          <button type="button" className="pweye" onClick={() => setShow(!show)} disabled={busy}
            aria-label={show ? 'hide the password' : 'show the password'} aria-pressed={show} title={show ? 'hide' : 'show'}>
            {show ? EyeOffIcon : EyeIcon}
          </button>
        </div>
        <button disabled={busy || !pw}>{busy && <Spinner />}{busy ? 'Signing in…' : 'Sign in'}</button>
        {err && <div className="error">{err}</div>}
      </form>
    </div>
  )
}