work.suroh.tk/_includes/components/nav-primary.js

import { Synth } from '../../assets/js/synth.js'

class NavPrimary extends HTMLElement {
  categories = []
  subs = []

  audioEngine = null
  masterGain = null

  menuVoices = {}

  connectedCallback() {
    this.setupAudio()

    this.categories = this.querySelectorAll('nav-link')
    this.subs = this.querySelectorAll('ul')

    this.activate()

    window.addEventListener('popstate', () => {
      this.activate()
    })

    this.categories.forEach(n => {
      this.setupVoice(n)

      n.addEventListener('click', () => {
        const category = n.attributes.getNamedItem('category')
        const link = n.attributes.getNamedItem('link')

        console.log(link)

        if (link) {
          history.pushState({}, '', link.value)
          location.pathname = link.value
        } else if (category) {
          location.hash = category.value
        }
      })

      n.addEventListener('mouseenter', () => {
        const menuItem = this.querySelector('#menuItem h1')
        menuItem.textContent = n.dataset.name

        this.menuVoices[n.dataset.name].noteOn()

        menuItem.classList.add('active')
      })

      n.addEventListener('mouseleave', () => {
        const menuItem = this.querySelector('#menuItem h1')

        this.menuVoices[n.dataset.name].noteOff()

        menuItem.classList.remove('active')
      })
    })

    const audioEl = this.querySelector('.audioToggle')
    audioEl.addEventListener('click', () => this.toggleAudio())
  }

  activate() {
    let active, toOpen


    this.categories.forEach(c => {
      const { value } = c.attributes.getNamedItem('category') || false

      if (c.classList.contains('active')) {
        c.classList.remove('active')
      } else if (value == location.hash.replace('#', '')) {
        c.classList.add('active')
      }
    })

    this.subs.forEach(s => {
      const { name } = s.dataset

      if (name == location.hash.replace('#', '') || name == location.pathname) {
        toOpen = s
      } else if (s.classList.contains('active')){
        active = s
      }
    })

    if (active) {
      active.addEventListener('transitionend', () => {
        toOpen.classList.add('active')
      }, { once: true })

      active.classList.remove('active')
    } else if (toOpen) {
      toOpen.classList.add('active')
    }
  }

  setupAudio() {
    // AUDIO SETUP
    this.audioEngine = new (window.AudioContext || window.webkitAudioContext)()
    this.audioEngine.suspend()
    this.masterGain = this.audioEngine.createGain()

    this.masterGain.gain.value = 0.9
    this.masterGain.connect(this.audioEngine.destination)
  }

  toggleAudio() {
    const audioEl = this.querySelector('.audioToggle')

    if (this.audioEngine.state == 'suspended') {
      this.audioEngine.resume()
      audioEl.classList.add('active')
    } else {
      this.audioEngine.suspend()
      audioEl.classList.remove('active')
    }
  }

  setupVoice(el) {
    // create synthVoices per navItem
    this.menuVoices[el.dataset.name] = new Synth(this.audioEngine)
    this.menuVoices[el.dataset.name].gain.connect(this.masterGain)
  }
}

customElements.define('nav-primary', NavPrimary)