(function () {

    function initSlider(slider) {

        if (slider.dataset.initialized === "true") return;

        const slides = slider.querySelectorAll(".mp-slide");
        const prev = slider.querySelector(".mp-prev");
        const next = slider.querySelector(".mp-next");

        if (!slides.length) return;

        let index = 0;

        function showSlide(i) {
            slides.forEach(s => s.classList.remove("active"));
            slides[i].classList.add("active");
        }

        if (next) {
            next.addEventListener("click", function () {
                index = (index + 1) % slides.length;
                showSlide(index);
            });
        }

        if (prev) {
            prev.addEventListener("click", function () {
                index = (index - 1 + slides.length) % slides.length;
                showSlide(index);
            });
        }

        slider.dataset.initialized = "true";
    }

    function initInDocument(doc) {
        doc.querySelectorAll(".mp-slider").forEach(initSlider);
    }

    function initFrontend() {
        initInDocument(document);
    }

    function initEditor() {

        const iframe = document.querySelector("iframe[name='editor-canvas']");

        if (!iframe) return;

        const iframeDoc = iframe.contentDocument || iframe.contentWindow.document;

        if (!iframeDoc) return;

        const observer = new MutationObserver(function () {
            initInDocument(iframeDoc);
        });

        observer.observe(iframeDoc.body, {
            childList: true,
            subtree: true
        });

        initInDocument(iframeDoc);
    }

    document.addEventListener("DOMContentLoaded", function () {

        // фронтенд
        if (!document.body.classList.contains("block-editor-page")) {
            initFrontend();
        }

        // editor
        if (document.body.classList.contains("block-editor-page")) {
            setTimeout(initEditor, 800);
        }

    });

})();