wavesurfer.js/dist/plugins/zoom.js

Audio waveform player

class t{constructor(){this.listeners={}}on(t,e,s){if(this.listeners[t]||(this.listeners[t]=new Set),this.listeners[t].add(e),null==s?void 0:s.once){const s=()=>{this.un(t,s),this.un(t,e)};return this.on(t,s),s}return()=>this.un(t,e)}un(t,e){var s;null===(s=this.listeners[t])||void 0===s||s.delete(e)}once(t,e){return this.on(t,e,{once:!0})}unAll(){this.listeners={}}emit(t,...e){this.listeners[t]&&this.listeners[t].forEach((t=>t(...e)))}}class e extends t{constructor(t){super(),this.subscriptions=[],this.options=t}onInit(){}_init(t){this.wavesurfer=t,this.onInit()}destroy(){this.emit("destroy"),this.subscriptions.forEach((t=>t()))}}const s={scale:.5,deltaThreshold:5,exponentialZooming:!1,iterations:20};class i extends e{constructor(t){super(t||{}),this.wrapper=void 0,this.container=null,this.accumulatedDelta=0,this.pointerTime=0,this.oldX=0,this.endZoom=0,this.startZoom=0,this.onWheel=t=>{if(this.wavesurfer&&this.container&&!(Math.abs(t.deltaX)>=Math.abs(t.deltaY))&&(t.preventDefault(),this.accumulatedDelta+=-t.deltaY,0===this.startZoom&&this.options.exponentialZooming&&(this.startZoom=this.wavesurfer.getWrapper().clientWidth/this.wavesurfer.getDuration()),0===this.options.deltaThreshold||Math.abs(this.accumulatedDelta)>=this.options.deltaThreshold)){const e=this.wavesurfer.getDuration(),s=0===this.wavesurfer.options.minPxPerSec?this.wavesurfer.getWrapper().scrollWidth/e:this.wavesurfer.options.minPxPerSec,i=t.clientX-this.container.getBoundingClientRect().left,o=this.container.clientWidth,n=this.wavesurfer.getScroll();i===this.oldX&&0!==this.oldX||(this.pointerTime=(n+i)/s),this.oldX=i;const r=this.calculateNewZoom(s,this.accumulatedDelta),h=o/r*(i/o);r*e<o?(this.wavesurfer.zoom(o/e),this.container.scrollLeft=0):(this.wavesurfer.zoom(r),this.container.scrollLeft=(this.pointerTime-h)*r),this.accumulatedDelta=0}},this.calculateNewZoom=(t,e)=>{let s;if(this.options.exponentialZooming){const i=e>0?Math.pow(this.endZoom/this.startZoom,1/(this.options.iterations-1)):Math.pow(this.startZoom/this.endZoom,1/(this.options.iterations-1));s=Math.max(0,t*i)}else s=Math.max(0,t+e*this.options.scale);return Math.min(s,this.options.maxZoom)},this.options=Object.assign({},s,t)}static create(t){return new i(t)}onInit(){var t;this.wrapper=null===(t=this.wavesurfer)||void 0===t?void 0:t.getWrapper(),this.wrapper&&(this.container=this.wrapper.parentElement,this.container.addEventListener("wheel",this.onWheel),void 0===this.options.maxZoom&&(this.options.maxZoom=this.container.clientWidth),this.endZoom=this.options.maxZoom)}destroy(){this.wrapper&&this.wrapper.removeEventListener("wheel",this.onWheel),super.destroy()}}export{i as default};