aswi2021mr-proper-gitlab/application/view/js-scripts/paging.js @ af2e04cd

function checkValidItemsPerPage(){
    var visibleItemCount = document.getElementById("itemsPerPage");
    if(!isNaN(visibleItemCount.value) && visibleItemCount.value % 1 === 0 && parseInt(visibleItemCount.value) >= 1 && parseInt(visibleItemCount.value) <= 500){
        return true;
    }else{
        alert("Zadaný počet není validní, zkuste to znovu.\nPlatný rozsah: 1 - 500 položek na stránku.");
        visibleItemCount.value = itemPerPage;
        return false;
    }
}

function changeItemsPerPage(){
    //if there is no valid input, return and dont save
    if(checkValidItemsPerPage() === false){
        return;
    }

    pageIndex = 0;
    var visibleItemCount = document.getElementById("itemsPerPage").value;
    itemPerPage = visibleItemCount;
    fetchData(true);
}

function moveToFirst(){
    pageIndex = 0;
    fetchData(true);
}

function moveToPrevious(){
    pageIndex = (pageIndex - 1 > 0) ? (pageIndex - 1) : (0);
    fetchData(true);
}

function moveToNext(){
    pageIndex = (pageIndex + 1 < pageCount) ? (pageIndex + 1) : (pageCount - 1);
    fetchData(true);
}

function moveToLast(){
    pageIndex = pageCount - 1;
    fetchData(true);
}

function onManualPageStart(element){
    element.value = '';
}

function onManualPageEnd(element) {
    const value = Number(element.value) - 1;
    if(Number.isInteger(value) && value >= 0 && value < pageCount){
        pageIndex = value;
        fetchData(true);
    } else {
        element.value = (pageIndex + 1) + " / " + pageCount;
    }

}