const MAX_EXECUTIONS = 12;
const ROTATION_INTERVAL = 12000;

const executions = {};

function banner(mapping) {

    Object.keys(mapping).forEach(
        (cur) => {
            bannerGroup(mapping[cur], cur);
        }
    );
}

function bannerGroup(group, grpName) {
    resortGroup(group);
    executions[grpName] = executions[grpName] ? executions[grpName] + 1 : 1;

    const amount = group.placeholders.length;
    const rval = group.banners.prio.slice(0, amount);
    if (rval.length < amount) {
        rval.push(
            ...group.banners.generic.slice(0, amount - rval.length)
        );
    }
    if (rval.length >  0) {
        $.ajax({
            url: "stats/bannerMultiImpression.php",
            method: "POST",
            data: { 
                banners: rval.map(e => e.id).join(","),
                source: document.URL
            },
            dataType: "html"
        });
        rval.forEach(v => {
            v.views++;
        });
        const enough = rval.length == amount;
        group.placeholders.forEach(
            (target) => {
                if (rval.length >  0) {
                    const ele = rval.shift();
                    let mediaHtml = ele.media;
                    if (ele.link) {
                        const a = document.createElement('a');
                        a.href = ele.link;
                        a.target = "_blank";
                        a.innerHTML = ele.media;
                        mediaHtml = a;
                    }
                    mediaHtml.addEventListener(
                        'click',
                        () => {
                            $.ajax({
                                url: "stats/bannerClick.php",
                                method: "POST",
                                data: { 
                                    banner: ele.id,
                                    source: document.URL
                                },
                                dataType: "html"
                            });
                        }
                    );
                    $('#'+target).html(mediaHtml);
                }
            }
        );
    
        if (enough && executions[grpName] <= MAX_EXECUTIONS) {
            setTimeout(
                () => {
                    bannerGroup(group, grpName);
                },
                ROTATION_INTERVAL
            );
        }

    }
    
}


function resortGroup(group) {
    group.banners.prio.sort(compareEle)
    group.banners.generic.sort(compareEle)
}

function compareEle(a, b) {
    return a.views - b.views;
}