/* ads-consent.js — Google Ads tag, gated behind a consent banner. Page-side only.
 *
 * Page: /odoo-black-friday/. Companion to /static/black-friday.js (which is untouched).
 * The tag ID and the conversion label are read from the banner element's data-* attributes
 * (#adsConsent[data-ads-id][data-ads-send-to]), so this file stays generic and reusable and
 * the page holds the one copy of the config. Without those attributes the script stays inert.
 *
 * WHY A GATE: the Google Ads tag is NOT cookieless — it sets the advertising cookies
 * _gcl_au / _gcl_aw. So nothing loads and no request fires until the visitor accepts.
 * The default is DENY. Declining genuinely prevents the tag from loading.
 *
 * WHAT THE CONVERSION IS: a CLICK PROXY, not a sale. It fires when a buy form on this page
 * is submitted. The real purchase is measured on the checkout host (20.odoo4projects.com)
 * by odoo-dev. See wiki/concepts/conversion-tracking-contract. Never label it a sale.
 *
 * SAFETY: a conversion tag must never swallow a buy. On submit we fire the event and submit
 * the form from the event callback, with a hard timeout that submits anyway. With JavaScript
 * off the native POST forms submit untouched (no banner, no conversion, no error).
 */
(function () {
  "use strict";

  var STORE_KEY = "o4p_ads_consent"; // "granted" | "denied"
  var SUBMIT_FALLBACK_MS = 700;      // hard cap: submit even if the tag never answers
  var cfg = null;                    // { id, sendTo } — read from the banner, never hard-coded

  /* ---- the visitor's stored choice ---- */
  function readChoice() {
    try {
      return window.localStorage.getItem(STORE_KEY);
    } catch (e) {
      return null;
    }
  }
  function saveChoice(value) {
    try {
      window.localStorage.setItem(STORE_KEY, value);
    } catch (e) {
      /* private mode / storage disabled: treat as no choice, banner stays up */
    }
  }
  function isGranted() {
    return readChoice() === "granted";
  }

  /* ---- cookie removal (only used to revoke a prior grant) ---- */
  function clearCookie(name) {
    var host = window.location.hostname;
    var bare = host.replace(/^www\./, "");
    var paths = ["/", "/odoo-black-friday/"];
    var domains = ["", "; domain=" + host, "; domain=." + bare];
    for (var i = 0; i < paths.length; i++) {
      for (var j = 0; j < domains.length; j++) {
        document.cookie =
          name + "=; expires=Thu, 01 Jan 1970 00:00:00 GMT; path=" + paths[i] + domains[j];
      }
    }
  }
  function clearAdsCookies() {
    clearCookie("_gcl_au");
    clearCookie("_gcl_aw");
  }

  /* ---- the tag: loaded ONLY on consent ---- */
  function loadGtag() {
    if (!cfg || window.__o4pAdsLoaded) return;
    window.__o4pAdsLoaded = true;
    window.dataLayer = window.dataLayer || [];
    window.gtag =
      window.gtag ||
      function () {
        window.dataLayer.push(arguments);
      };
    window.gtag("js", new Date());
    window.gtag("config", cfg.id);
    var s = document.createElement("script");
    s.async = true;
    s.src = "https://www.googletagmanager.com/gtag/js?id=" + cfg.id;
    document.head.appendChild(s);
  }

  /* ---- the conversion proxy, fired on a buy-form submit ---- */
  function onSubmit(e) {
    var form = e.target;
    if (!form || form.tagName !== "FORM") return;
    var action = form.getAttribute("action") || "";
    if (action.indexOf("/shop/post_basket") === -1) return;

    // Not configured, no consent, or no tag: do nothing, let the native POST go through.
    if (!cfg || !isGranted() || typeof window.gtag !== "function") return;

    e.preventDefault();
    var submitted = false;
    function submitNow() {
      if (submitted) return;
      submitted = true;
      form.submit(); // bypasses the submit event: no loop, no re-fire
    }
    try {
      window.gtag("event", "conversion", {
        send_to: cfg.sendTo,
        event_callback: submitNow,
      });
    } catch (err) {
      submitNow();
    }
    // Hard fallback: a blocked / slow / failed tag must never stop the purchase.
    window.setTimeout(submitNow, SUBMIT_FALLBACK_MS);
  }

  /* ---- the banner ---- */
  function bannerEl() {
    return document.getElementById("adsConsent");
  }
  function showBanner() {
    var el = bannerEl();
    if (el) el.hidden = false;
  }
  function hideBanner() {
    var el = bannerEl();
    if (el) el.hidden = true;
  }
  function accept() {
    saveChoice("granted");
    loadGtag();
    hideBanner();
  }
  function decline() {
    saveChoice("denied");
    clearAdsCookies();
    hideBanner();
  }

  function init() {
    document.addEventListener("submit", onSubmit, false);

    var banner = bannerEl();
    if (!banner) return;

    // Config lives in the page. Missing config -> stay inert (no tag, no conversion).
    var id = banner.getAttribute("data-ads-id");
    var sendTo = banner.getAttribute("data-ads-send-to");
    if (!id || !sendTo) return;
    cfg = { id: id, sendTo: sendTo };

    var choice = readChoice();
    if (choice === "granted") {
      loadGtag(); // returning visitor who already accepted: load straight away
    } else if (choice !== "denied") {
      showBanner(); // first visit (or no stored choice): default deny, ask
    }

    var acceptBtn = document.getElementById("adsConsentAccept");
    if (acceptBtn) acceptBtn.addEventListener("click", accept);
    var declineBtn = document.getElementById("adsConsentDecline");
    if (declineBtn) declineBtn.addEventListener("click", decline);

    // A real way to change the choice later.
    var opener = document.getElementById("adsConsentOpen");
    if (opener) {
      opener.addEventListener("click", function (e) {
        e.preventDefault();
        showBanner();
      });
    }
  }

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