// ==UserScript==
// @name         Sound Limiter for Weibo Video Clips
// @name:zh-CN   微博视频音量限制器
// @namespace    http://tampermonkey.net/
// @version      0.6
// @description  Limit the default sound volume of video clips on weibo.com to 10%.
// @description:zh-cn  限制微博视频的默认音量为10%
// @icon         https://raw.githubusercontent.com/hbliu104/weibo-volume-limiter/main/vol_down.png
// @author       Lophelia
// @include        http://f.video.weibocdn.com/*
// @include        https://video.h5.weibo.cn/*
// @include        https://*weibo.com/*
// @require  http://ajax.googleapis.com/ajax/libs/jquery/1.7.2/jquery.min.js
// @run-at document-idle
// @downloadURL none
// ==/UserScript==

function waitForKeyElements (
    selectorTxt,    /* Required: The jQuery selector string that
                        specifies the desired element(s).
                    */
    actionFunction, /* Required: The code to run when elements are
                        found. It is passed a jNode to the matched
                        element.
                    */
    bWaitOnce,      /* Optional: If false, will continue to scan for
                        new elements even after the first match is
                        found.
                    */
    iframeSelector  /* Optional: If set, identifies the iframe to
                        search.
                    */
) {
    var targetNodes, btargetsFound;

    if (typeof iframeSelector == "undefined")
        targetNodes     = $(selectorTxt);
    else
        targetNodes     = $(iframeSelector).contents ()
                                           .find (selectorTxt);

    if (targetNodes  &&  targetNodes.length > 0) {
        btargetsFound   = true;
        /*--- Found target node(s).  Go through each and act if they
            are new.
        */
        targetNodes.each ( function () {
            var jThis        = $(this);
            var alreadyFound = jThis.data ('alreadyFound')  ||  false;

            if (!alreadyFound) {
                //--- Call the payload function.
                var cancelFound     = actionFunction (jThis);
                if (cancelFound)
                    btargetsFound   = false;
                else
                    jThis.data ('alreadyFound', true);
            }
        } );
    }
    else {
        btargetsFound   = false;
    }

    //--- Get the timer-control variable for this selector.
    var controlObj      = waitForKeyElements.controlObj  ||  {};
    var controlKey      = selectorTxt.replace (/[^\w]/g, "_");
    var timeControl     = controlObj [controlKey];

    //--- Now set or clear the timer as appropriate.
    if (btargetsFound  &&  bWaitOnce  &&  timeControl) {
        //--- The only condition where we need to clear the timer.
        clearInterval (timeControl);
        delete controlObj [controlKey]
    }
    else {
        //--- Set a timer, if needed.
        if ( ! timeControl) {
            timeControl = setInterval ( function () {
                    waitForKeyElements (    selectorTxt,
                                            actionFunction,
                                            bWaitOnce,
                                            iframeSelector
                                        );
                },
                300
            );
            controlObj [controlKey] = timeControl;
        }
    }
    waitForKeyElements.controlObj   = controlObj;
}

let flag = 0;

waitForKeyElements ("video", volume_down);

function volume_down () {
    let videos = document.getElementsByTagName('video');
    for (let idx = 0; idx < videos.length; idx++)
    {
        if (videos[idx].hasAttribute('autoplay'))
        {
            videos[idx].removeAttribute('autoplay');
        }
        videos[idx].volume = 0.1;
        flag++;
    }
    if (flag < 2)
    {
        return true;
    }

}