export function setupPlayButton(
    sources: Map<number, AudioBufferSourceNode>,
    gains: Map<number, GainNode>,
    context: AudioContext
  ) {
    const button = document.createElement('button')
    button.textContent = '▶ Play All'
    button.style.fontSize = '1.5rem'
    button.style.padding = '10px'
    button.style.marginTop = '20px'
  
    button.onclick = () => {
      const startTime = context.currentTime + 0.1 // 100ms in Zukunft
      const rampTime = 2
  
      sources.forEach((source, freq) => {
        const gainNode = gains.get(freq)
        if (!gainNode) return
  
        // Ramp up GainNode
        const gain = gainNode.gain
        gain.setValueAtTime(0.001, startTime)
        gain.exponentialRampToValueAtTime(1.0, startTime + rampTime)
  
        // Start BufferSource
        try {
          source.start(startTime)
          console.log(`Started ${freq}Hz at ${startTime.toFixed(2)}`)
        } catch (err) {
          console.warn(`Start error for ${freq}Hz`, err)
        }
      })
  
      button.disabled = true
      button.textContent = '🔊 Playing...'
    }
  
    document.body.appendChild(button)
  }