import { describe, expect, it } from 'vitest'
import { wireTypeaheadSubmit } from './typeahead'

function setup() {
  const input = Object.assign(new EventTarget(), { value: '' })
  const host = new EventTarget()
  let submits = 0
  wireTypeaheadSubmit(input, { requestSubmit: () => submits++ }, host)
  const press = (key: string) => input.dispatchEvent(Object.assign(new Event('keydown'), { key }))
  const type = (value = 'x') => {
    input.value = value
    input.dispatchEvent(new Event('input'))
  }
  // A pointer pick: the component fills the input from its shadow-root
  // pointerup listener (no 'input' event), then the event reaches the host.
  const clickSuggestion = (handle: string) => {
    input.value = handle
    host.dispatchEvent(new Event('pointerup'))
  }
  // A pointerup that reaches the host without picking anything, e.g. on the
  // dropdown's padding.
  const clickHostChrome = () => host.dispatchEvent(new Event('pointerup'))
  return { press, type, clickSuggestion, clickHostChrome, submits: () => submits }
}

describe('wireTypeaheadSubmit', () => {
  it('submits on Enter when the user has not navigated the suggestions', () => {
    const t = setup()
    t.type()
    t.press('Enter')
    expect(t.submits()).toBe(1)
  })

  it('lets the first Enter after arrow navigation pick the suggestion, then submits', () => {
    const t = setup()
    t.type()
    t.press('ArrowDown')
    t.press('Enter')
    expect(t.submits()).toBe(0)
    t.press('Enter')
    expect(t.submits()).toBe(1)
  })

  it('submits after Escape dismisses the menu', () => {
    const t = setup()
    t.press('ArrowDown')
    t.press('Escape')
    t.press('Enter')
    expect(t.submits()).toBe(1)
  })

  it('treats further typing as leaving the suggestion highlight', () => {
    const t = setup()
    t.press('ArrowDown')
    t.type()
    t.press('Enter')
    expect(t.submits()).toBe(1)
  })

  it('submits when clicking a suggestion fills in an account', () => {
    const t = setup()
    t.type('ali')
    t.clickSuggestion('alice.example.com')
    expect(t.submits()).toBe(1)
  })

  it('does not submit a pointerup that picked nothing', () => {
    const t = setup()
    t.type('ali')
    t.clickHostChrome()
    expect(t.submits()).toBe(0)
  })

  it('does not resubmit the same pick twice', () => {
    const t = setup()
    t.type('ali')
    t.clickSuggestion('alice.example.com')
    t.clickHostChrome()
    expect(t.submits()).toBe(1)
  })
})