<template>
  <div class="recorder">
    <icon
      v-if="!isRecording"
      title="record voice"
      class="recordBtn start"
      ic="./sym/ic_mic_white.svg"
      @click.native="startRecording()"
      ref="startRecord"
    />
    <div v-else class="voiceMeterContainer">
      <div class="voiceMeter" ref="voiceMeter"></div>
      <icon
        title="record voice"
        class="recordBtn stop"
        ic="./sym/ic_mic_white.svg"
        @click.native="stopRecording()"
        ref="stopRecord"
      />
    </div>
  </div>
</template>

<script>
import icon from '@/components/icon';
import Recorder from 'recorder-js';
const audioContext =  new (window.AudioContext || window.webkitAudioContext)();

export default {
  name: 'soundRecorder',
  components: {
    icon
  },
  props: {
    onStart: {
      type: Function,
      default: ()=>{}
    },
    onStop: {
      type: Function,
      default: ()=>{}
    }
  },
  methods: {
    startRecording(){
      this.onStart();
      navigator.mediaDevices.getUserMedia({audio: true})
        .then(stream => {
          this.recorder.init(stream);
          this.recorder.start().then(()=>this.isRecording=true);
        })
        .catch(err => console.log('unable to get stream', err));
    },
    stopRecording(){
      this.recorder.stop()
        .then(({blob}) => {
          blob.name = `Recording-${new Date().toISOString()}.${blob.type.split('/')[1]}`;
          this.onStop({blob});
          this.isRecording=false;
        });
    },
    setVoiceMeter(value){
      if (!this.$refs.stopRecord) return;
      this.$refs.voiceMeter.style.height = `calc(3rem + ${value/4}px`;
      this.$refs.voiceMeter.style.width = `calc(3rem + ${value/4}px`;
    },
  },
  data(){
    return{
      recorder: new Recorder(audioContext, {
        onAnalysed: data => this.setVoiceMeter(data.lineTo)
      }),
      isRecording: false
    }
  }
}
</script>

<style scoped lang="scss">
.recordBtn{
  position: absolute;
  right: 1rem;
  bottom: 0.25rem;
  background-color: #1d1d1d;
  border-radius: 50%;
}
.recordBtn.stop{
  right: 0;
  bottom: 0;
  background-color: #c63e3e;
  box-shadow: none;
}
.voiceMeter{
  position: absolute;
  background-color: #fff;
  top: 50%;
  left: 50%;
  transform: translate(-50%,-50%);
  border-radius: 50%;
  box-shadow: 3px 3px 10px #111;
}
.voiceMeterContainer{
  position: absolute;
  height: 3rem;
  width: 3rem;
  bottom: 0.25rem;
  right: 1rem;
}
.recorder{
  height: 100%;
  width: 8rem;
  overflow: hidden;
}
</style>