import { test } from 'node:test'
import assert from 'node:assert/strict'
import { readFileSync } from 'node:fs'
import vm from 'node:vm'

// public/kundenansicht.js im Browser-Nachbau: Kennung X-Kundenansicht an jede eigene /api-Anfrage,
// Hinweis-Overlay bei ersetzter (409 view_replaced) oder abgelaufener (401 view_expired) Ansicht
const SRC = readFileSync(new URL('../public/kundenansicht.js', import.meta.url), 'utf8')
const ID = 'a'.repeat(32)

function fakeElement(tag) {
  return {
    tag,
    id: '',
    className: '',
    textContent: '',
    type: '',
    children: [],
    attrs: {},
    listeners: {},
    appendChild(child) {
      this.children.push(child)
      return child
    },
    setAttribute(name, value) {
      this.attrs[name] = value
    },
    addEventListener(name, fn) {
      this.listeners[name] = fn
    },
  }
}

function browser({ respond = () => ({ status: 200, body: {} }) } = {}) {
  const calls = []
  const body = fakeElement('body')
  const all = () => {
    const out = []
    const walk = (n) => {
      out.push(n)
      n.children.forEach(walk)
    }
    walk(body)
    return out
  }
  const document = {
    body,
    createElement: (tag) => fakeElement(tag),
    getElementById: (id) => all().find((n) => n.id === id) || null,
  }
  const xhrs = []
  class XMLHttpRequest {
    constructor() {
      this.headers = {}
      this.listeners = {}
      xhrs.push(this)
    }
    open(method, url) {
      this.method = method
      this.url = url
    }
    setRequestHeader(name, value) {
      this.headers[name] = value
    }
    addEventListener(name, fn) {
      this.listeners[name] = fn
    }
    send() {
      this.sent = true
    }
  }
  const ctx = {
    URL,
    Headers,
    Response,
    console,
    document,
    XMLHttpRequest,
    location: { href: 'https://project.webklar.com/dashboard.html', origin: 'https://project.webklar.com' },
    close: () => {
      ctx.closed = true
    },
    fetch: async (input, init = {}) => {
      calls.push({ url: typeof input === 'string' ? input : input.url, headers: new Headers(init.headers || {}) })
      const { status, body: json } = respond(input)
      return new Response(JSON.stringify(json), { status, headers: { 'content-type': 'application/json' } })
    },
  }
  ctx.window = ctx
  vm.createContext(ctx)
  vm.runInContext(SRC, ctx)
  const overlayText = () => {
    const box = document.getElementById('kb-view-overlay')
    if (!box) return null
    const texts = []
    const walk = (n) => {
      if (n.textContent) texts.push(n.textContent)
      n.children.forEach(walk)
    }
    walk(box)
    return texts.join(' | ')
  }
  return { ctx, calls, xhrs, overlayText }
}

const settle = () => new Promise((resolve) => setTimeout(resolve, 10))

test('ohne ID kein Header', async () => {
  const { ctx, calls } = browser()
  await ctx.fetch('/api/projects')
  assert.equal(calls[0].headers.get('x-kundenansicht'), null)
})

test('mit ID: Header bei /api/... gleicher Herkunft, nicht bei fremder Herkunft oder /img', async () => {
  const { ctx, calls } = browser()
  ctx.KbView.setId(ID)
  assert.equal(ctx.KbView.id(), ID)
  await ctx.fetch('/api/projects')
  await ctx.fetch('https://example.org/api/x')
  await ctx.fetch('/img/logo.png')
  await ctx.fetch('https://project.webklar.com/api/news', { method: 'POST', headers: { 'Content-Type': 'application/json' } })
  assert.equal(calls[0].headers.get('x-kundenansicht'), ID)
  assert.equal(calls[1].headers.get('x-kundenansicht'), null)
  assert.equal(calls[2].headers.get('x-kundenansicht'), null)
  assert.equal(calls[3].headers.get('x-kundenansicht'), ID)
  assert.equal(calls[3].headers.get('content-type'), 'application/json', 'vorhandene Header bleiben')
})

test('409 view_replaced zeigt Overlay mit Kundennamen, Antwort bleibt lesbar', async () => {
  const { ctx, overlayText } = browser({ respond: () => ({ status: 409, body: { code: 'view_replaced', kunde: 'Kunde Zwei', error: 'x' } }) })
  ctx.KbView.setId(ID)
  const res = await ctx.fetch('/api/projects')
  assert.equal((await res.json()).code, 'view_replaced')
  await settle()
  assert.match(overlayText(), /Diese Ansicht wurde durch die Kundenansicht von Kunde Zwei ersetzt\./)
  assert.match(overlayText(), /Tab schließen/)
})

test('401 view_expired zeigt Abgelaufen-Overlay, andere 401 nicht', async () => {
  const other = browser({ respond: () => ({ status: 401, body: { error: 'Nicht angemeldet' } }) })
  await other.ctx.fetch('/api/projects')
  await settle()
  assert.equal(other.overlayText(), null)
  const { ctx, overlayText } = browser({ respond: () => ({ status: 401, body: { code: 'view_expired' } }) })
  await ctx.fetch('/api/projects')
  await settle()
  assert.match(overlayText(), /Die Kundenansicht ist abgelaufen\. Bitte im Ticketsystem erneut öffnen\./)
})

test('Overlay-Knopf schliesst den Tab, zweiter Hinweis ersetzt den Text statt zu stapeln', async () => {
  const { ctx, overlayText } = browser()
  ctx.KbView.showReplaced('Kunde Zwei')
  ctx.KbView.showExpired()
  const box = ctx.document.getElementById('kb-view-overlay')
  assert.equal(ctx.document.body.children.length, 1)
  assert.match(overlayText(), /abgelaufen/)
  const find = (n) => (n.tag === 'button' ? n : n.children.map(find).find(Boolean))
  find(box).listeners.click()
  assert.equal(ctx.closed, true)
})

test('XHR bekommt den Header ebenfalls (nur eigene /api-Adressen)', () => {
  const { ctx, xhrs } = browser()
  ctx.KbView.setId(ID)
  const a = new ctx.XMLHttpRequest()
  a.open('POST', '/api/chat/attachments')
  a.send()
  const b = new ctx.XMLHttpRequest()
  b.open('GET', 'https://example.org/api/x')
  b.send()
  assert.equal(xhrs[0].headers['X-Kundenansicht'], ID)
  assert.equal(xhrs[1].headers['X-Kundenansicht'], undefined)
})