Method updateLyricHighlight

js/ReadingSystem.js:478–520

* 更新歌词高亮

()

   * 更新歌词高亮
   */
  updateLyricHighlight() {
    if (!this.lyricLineEls.length || !this.dom.audioPlayer || this.state.sentence) {
      return;
    }

    if (this.state.loopMode !== 'list') {
      this.state.sentence = true;
    }

    const currentTime = this.dom.audioPlayer.currentTime;
    let newIndex = -1;

    for (let i = this.state.currentLyrics.length - 1; i >= 0; i--) {
      if (currentTime >= this.state.currentLyrics[i].time) {
        newIndex = i;
        break;
      }
    }

    if (newIndex === this.state.currentLyricIndex) return;

    // 移除旧高亮
    if (
      this.state.currentLyricIndex >= 0 &&
      this.lyricLineEls[this.state.currentLyricIndex]
    ) {
      removeClass(this.lyricLineEls[this.state.currentLyricIndex], 'active');
      removeClass(this.lyricLineEls[this.state.currentLyricIndex], 'pulse');
    }

    // 应用新高亮
    if (newIndex >= 0) {
      const activeLine = this.lyricLineEls[newIndex];
      if (activeLine) {
        addClass(activeLine, 'active');
        addClass(activeLine, 'pulse');
        if (this.shouldScrollLyricIntoView(activeLine)) {
          activeLine.scrollIntoView({ behavior: 'smooth', block: 'center' });
        }
      }
    }
    this.state.currentLyricIndex = newIndex;
  }

  /**
   * 判断歌词是否需要滚动到可视区域