// selection.mjs's hash: #<slide>[/<block>], read without ever throwing
// — and its teardown, which is what keeps a resync from leaving a
// second copy of every handler on the page's own elements.
import test from 'node:test'
import assert from 'node:assert/strict'
import { parseHash, formatHash, mountSelection } from './selection.mjs'
import { el, withDocument } from './dom-stub.mjs'

test('parseHash splits the slide and the block, and survives a stray %', () => {
  assert.deepEqual(parseHash('#slideaaaaaaa'), { slide: 'slideaaaaaaa', block: '' })
  assert.deepEqual(parseHash('#slideaaaaaaa/blockbbbbbbb'), { slide: 'slideaaaaaaa', block: 'blockbbbbbbb' })
  assert.deepEqual(parseHash(''), { slide: '', block: '' })
  assert.deepEqual(parseHash('#'), { slide: '', block: '' })
  assert.deepEqual(parseHash('#%'), { slide: '%', block: '' })
  assert.deepEqual(parseHash('#a%2Fb'), { slide: 'a', block: 'b' })
})

// A resync mounts a second selection over the SAME stage element and
// the same document, so the first one has to let go of both. The
// Escape handler is the one that bites: it is on `document`, so a
// leaked one clears a selection nobody is holding any more.
test('destroy takes the listeners off, and a second mount leaves one of each', () => {
  const ctx = withDocument()
  try {
    const stage = el('div', { 'slides-stage': '' })
    const first = mountSelection({ stageEl: stage, getSlideId: () => 'slideaaaaaaa' })
    assert.equal(stage.countListeners('click'), 1)
    assert.equal(ctx.document.countListeners('keydown'), 1)

    first.destroy()
    assert.equal(stage.countListeners('click'), 0)
    assert.equal(ctx.document.countListeners('keydown'), 0)

    const second = mountSelection({ stageEl: stage, getSlideId: () => 'slideaaaaaaa' })
    assert.equal(stage.countListeners('click'), 1, 'one click handler, not one per resync')
    assert.equal(ctx.document.countListeners('keydown'), 1)
    second.destroy()
  } finally {
    ctx.restore()
  }
})

test('formatHash is the inverse', () => {
  assert.equal(formatHash('s', 'b'), '#s/b')
  assert.equal(formatHash('s', ''), '#s')
  assert.equal(formatHash('', 'b'), '')
})