import { useState } from 'react'
import { api, message } from '../bridge.js'
import * as Icon from '../ui/icons.jsx'
import logo from '../assets/loyaly-mark.png'

// Linking this PC to a shop — the first thing that happens on a new install,
// and until now the one thing the app could not do.
//
// It comes BEFORE sign-in on purpose. The installer standing at a new counter
// has an installation code and, quite often, no account of their own yet; the
// PC's identity is not a person's identity. The endpoint behind this is
// deliberately unauthenticated for the same reason — requiring a login first
// would mean shipping a password to every shop that installs the software.
export default function Setup({ onDone, onCancel }) {
  const [code, setCode] = useState('')
  const [busy, setBusy] = useState(null)
  const [error, setError] = useState(null)

  async function submit(e) {
    e.preventDefault()
    setBusy('claim'); setError(null)
    try {
      onDone(await api.claim(code))
    } catch (err) {
      setError(message(err))
    } finally {
      setBusy(null)
    }
  }

  async function standalone() {
    setBusy('alone'); setError(null)
    try {
      onDone(await api.runStandalone())
    } catch (err) {
      setError(message(err))
    } finally {
      setBusy(null)
    }
  }

  // First launch: a choice, not a code box. Two thirds of the people who
  // open this have no idea what an installation code is; the other third has
  // one in their hand. Both must see their own path in the first second.
  const [path, setPath] = useState(onCancel ? 'code' : null)

  if (path === null) {
    return (
      <div className="login">
        <div className="box wide">
          <span className="mark"><img src={logo} alt="" /></span>
          <h1>Welcome to Behavision</h1>
          <p className="lead">
            This PC will watch your shop’s cameras and recognise returning customers.
            First, one question: is this shop managed from a head office?
          </p>
          <div className="choices">
            <button type="button" className="choice" onClick={() => setPath('code')}>
              <Icon.Cloud size={22} />
              <b>Yes — I have an installation code</b>
              <span>Head office gave you a code like <em>ABCDEF-123456-…</em>. This PC joins that shop and gets its cameras from there.</span>
            </button>
            <button type="button" className="choice" onClick={() => setPath('alone')}>
              <Icon.Shield size={22} />
              <b>No — set up on this PC only</b>
              <span>Cameras, customers and recognition stay on this PC. Nothing is sent anywhere. You can link to a head office later.</span>
            </button>
          </div>
        </div>
      </div>
    )
  }

  if (path === 'alone') {
    return (
      <div className="login">
        <div className="box">
          <span className="mark"><img src={logo} alt="" /></span>
          <h1>On this PC only</h1>
          <p className="lead">
            Behavision will run entirely here. Next you’ll add your camera — it can find it on the network for you — and walk past it once so it can prove it works.
          </p>
          {error && <div className="err"><Icon.Warning size={15} />{error}</div>}
          <button type="button" className="btn primary" disabled={!!busy} onClick={standalone}>
            {busy === 'alone' ? 'Setting up…' : 'Continue'}
          </button>
          <div className="alt">
            <button type="button" className="linkbtn" onClick={() => setPath(null)}><Icon.Back size={14} /> Back</button>
          </div>
        </div>
      </div>
    )
  }

  return (
    <div className="login">
      <div className="box">
        <span className="mark"><img src={logo} alt="" /></span>
        <h1>{onCancel ? 'Link to head office' : 'Join your shop'}</h1>
        <p className="lead">
          Type the installation code head office gave you. It works once, and this PC becomes that shop.
        </p>
        <form onSubmit={submit}>
          {error && <div className="err"><Icon.Warning size={15} />{error}</div>}
          <label className="field">
            <span>Installation code</span>
            {/* Uppercase and letter-spaced because the code arrives read aloud
                down a phone or photographed off a screen. Spaces, dashes and
                case are stripped on the server, so what is typed here can be
                as untidy as it needs to be. */}
            <input value={code} autoFocus required
                   placeholder="ABCDEF-123456-GHIJKL-789012"
                   autoComplete="off" spellCheck="false"
                   style={{ textTransform: 'uppercase', letterSpacing: '.06em' }}
                   onChange={e => setCode(e.target.value)} />
          </label>
          <button className="btn primary" disabled={!!busy || code.trim().length < 6}>
            {busy === 'claim' ? 'Linking…' : 'Link this PC'}
          </button>
        </form>
        <p className="foot">
          Don’t have one? Whoever runs head office creates it under the shop: <em>Shops → the shop → Set up a shop PC</em>.
        </p>
        <div className="alt">
          {onCancel
            ? <button type="button" className="linkbtn" onClick={onCancel}>Not now — go back</button>
            : <button type="button" className="linkbtn" onClick={() => setPath(null)}><Icon.Back size={14} /> Back</button>}
        </div>
      </div>
    </div>
  )
}