(function () {
  if (window.__donationPluginLoaded) return;
  window.__donationPluginLoaded = true;

  let currentStep = 1;

  const STEP_RANGES = {
    1: [800, 1000],
    2: [1000, 1600],
    3: [800, 1000],
    4: [800, 1000],
  };

  const iframeState = new WeakMap();

  function applyHeight(iframe, rawHeight) {
    if (!iframe) return;

    let state = iframeState.get(iframe);

    if (!state) {
      state = {
        heightHistory: [0, 0, 0, 0, 0]
      };
      iframeState.set(iframe, state);
    }

    const [min, max] = STEP_RANGES[currentStep] || [0, Infinity];

    let h = rawHeight;

    if (h > min && h < max) {
      state.heightHistory[currentStep] = h;
    } else {
      h = state.heightHistory[currentStep];
    }

    if (h) {
      iframe.style.height = h + "px";
    }
  }

  window.addEventListener("message", function (event) {

    const {
      type,
      height,
      currentStep: step
    } = event.data || {};

    if (type === "donationIframeHeightonBtnClick") {
      currentStep = step;
    }

    if (type === "donationIframeHeight") {

      const iframe = Array
        .from(document.querySelectorAll(".donation-widget iframe"))
        .find(f => f.contentWindow === event.source);

      if (iframe) {
        applyHeight(iframe, height);
      }
    }
  });

  function createIframe(target) {

    const url = target.dataset.src;

    if (!url) return;

    if (target.querySelector("iframe")) return;

    const iframe = document.createElement("iframe");

    iframe.src = url;
    iframe.loading = "lazy";

    iframe.style.width = "100%";
    iframe.style.height = "100%";
  
    iframe.style.minHeight = "100vh";

    iframe.style.border = "0";
    iframe.style.overflow = "hidden";

    iframe.setAttribute("scrolling", "yes");

    target.appendChild(iframe);
  }

  function initPlugin() {

    document
      .querySelectorAll(".donation-widget")
      .forEach(createIframe);
  }

  if (document.readyState === "loading") {
    document.addEventListener("DOMContentLoaded", initPlugin);
  } else {
    initPlugin();
  }

  
})();