scrollToPosition.js

// scroll to id tagged element when there is a fixed sized header bar
function executeDelayed(f,...args){
    Promise.resolve().then(function(){
        window.requestAnimationFrame(function(){
            f.call(this,...args);
        });
    });
}
var queue=[];
window.addEventListener(/*"DOMContentLoaded"*/"load", processQueue);
function processQueue(){
    for(var e of queue) e.f.call(e.context,...e.args)
}
function executeOnLoad(f,...args){
    if(document.readyState === "complete" /*|| document.readyState === "interactive"*/) {
        processQueue();
        f.call(this,...args);
    }else{
        queue.push({f: f,args: args,context: this});
    }

}
var queue2=[];
function processQueue2(){
    for(var e of queue2) e.f.call(e.context,...e.args)
}
function isPreloaderActive(){ // this is theme specific
    return document.querySelector(".preloader").style.display!=="none";
}
function waitForPreloadInactive(){
    if(isPreloaderActive()){
        window.requestAnimationFrame(waitForPreloadInactive);
    }else{
        processQueue2();
    }
}

function executeAfterPreloader(f,...args){
    if(!isPreloaderActive()) {
        processQueue2();
        f.call(this,...args)
    }else{
        queue2.push({f: f,args: args,context: this});
    }
}
////
var queue3=[];
function processQueue3(){
    for(var e of queue3) e.f.call(e.context,...e.args)
}
var _previousHash=window.location.hash;
function executeAfterHashChange(f,...args){
    queue3.push({f: f,args: args,context: this});
}
window.addEventListener('hashchange', processQueue3, false);
////
var queue4=[];
function processQueue4(){
    for(var e of queue4) e.f.call(e.context,...e.args)
}
//var _previousHash=window.location.hash;
function executeAfterPopstate(f,...args){
    queue4.push({f: f,args: args,context: this});
}
window.addEventListener('popstate', processQueue4, false);
////
 
function isOnUeberUnsPage(){
    var pathname=window.location.pathname;
    return /ueber-uns/.exec(pathname)!==null;
}
function scrollToHash(){
    executeDelayed(function(){
        var hash=window.location.hash;
        if(isOnUeberUnsPage()&&hash){
            var element=document.querySelector(hash);
            var rect=element.getBoundingClientRect();
            var header=document.querySelector("#fixedNavigation");
            var headerRect=header.getBoundingClientRect();
            var positionY=rect.y+window.scrollY-rect.height-headerRect.height;
            // console.log({rect:rect,headerRect:headerRect, scrollY:window.scrollY,positionY:positionY});
            window.scrollTo(0, positionY);
        }
    });
}
waitForPreloadInactive();
executeOnLoad(function(){
    executeAfterPreloader(scrollToHash);
});

document.body.addEventListener('click',function(event){
    var target=event.target;
    if(target.tagName==="A"&&isOnUeberUnsPage()&&/ueber-uns/.exec(target.href)!==null){
        console.log(target.href);
        // Fix same href triggering on click, because it does not trigger
        // hashChange or popstate events
        if(window.location.hash===(new URL(target.href)).hash){
            console.log('same href trigger')
            executeDelayed(scrollToHash);
        }else{
            executeAfterHashChange(scrollToHash);
        }
        //executeAfterPopstate(scrollToHash);
    }
});