/**
 * 语音工具
 */
export class SpeakingTool {

    private static instance: SpeakingTool;

    static get Instance() {
        if (SpeakingTool.instance == null) {
            SpeakingTool.instance = new SpeakingTool();
        }
        return SpeakingTool.instance;
    }


    /**
     * 阅读一段文字
     * 会清空已有的阅读列表
     * @param msg 
     */
    speak(msg: string) {
        console.log("阅读" + msg);
        if (this.isIE()) {

        }
        else {

            this.clear();

            let speakMsg = new SpeechSynthesisUtterance(msg);
            speakMsg.lang = "zh-CN";
            speakMsg.rate = 1;
            speakMsg.pitch = 1.5;
            window.speechSynthesis.speak(speakMsg);

            return speakMsg;
        }
    }

    /**
     * 暂停正在进行的阅读
     * @param speakMsg 
     */
    pause() {
        window.speechSynthesis.pause();
    }
    /**
     * 继续之前暂停的阅读
     */
    resume() {
        window.speechSynthesis.resume();
    }

    /**
     * 清空进行中的阅读
     */
    clear() {
        window.speechSynthesis.cancel();
    }

    /**
     * IE浏览器
     */
    private isIE() {
        // if ("ActiveXObject" in window) {
        //     console.log("IE 浏览器")
        //     return true;
        // }
        // else {
        //     return false;
        // }
        return false;
    }

}