/* global window, document, localStorage */

const $ = selector => Array.from(document.querySelectorAll(selector));
const $$ = selector => Array.from(document.querySelector(selector));

(() => {
  "use strict";

  /**
   * Initialize the theme toggle button functionality.
   * Toggles between 'dark' and 'light' themes and persists the state in localStorage.
   */
  function initThemeToggle() {
    const themeToggleButton = document.getElementById("theme-toggle-btn");
    if (!themeToggleButton) return;
    themeToggleButton.addEventListener("click", () => {
      const documentRoot = document.documentElement;
      const isDarkTheme = documentRoot.classList.contains("dark");
      const newTheme = isDarkTheme ? "light" : "dark";

      if (newTheme === "light") {
        documentRoot.classList.remove("dark");
      } else {
        documentRoot.classList.add("dark");
      }
      documentRoot.setAttribute("data-theme", newTheme);
      localStorage.setItem("theme", newTheme);
    });
  }

  /**
   * Initialize event listeners for forms containing multiselect fields.
   * When the form is submitted, process each 'card-multiselect' to create hidden inputs.
   */
  function initCardMultiselectHandling() {
    const forms = document.querySelectorAll("form");
    forms.forEach(form => {
      if (form.querySelector("select.card-multiselect")) {
        form.addEventListener("submit", () => {
          processMultiselectForm(form);
        });
      }
    });
  }

  /**
   * Process multiselect fields within a form before submission by:
   *  - Creating hidden inputs for each selected option with value in 'card_id:quantity' format.
   *  - Removing the original name attribute to avoid duplicate submissions.
   *
   * @param {HTMLFormElement} form - The form element to process.
   */
  function processMultiselectForm(form) {
    const multiselectFields = form.querySelectorAll("select.card-multiselect");
    multiselectFields.forEach(selectField => {
      const originalFieldName =
        selectField.getAttribute("data-original-name") || selectField.getAttribute("name");
      if (!originalFieldName) return;
      selectField.setAttribute("data-original-name", originalFieldName);

      // Remove any previously generated hidden inputs for this multiselect.
      form
        .querySelectorAll(`input[data-generated-for-card-multiselect="${originalFieldName}"]`)
        .forEach(input => input.remove());

      // For each selected option, create a hidden input.
      selectField.querySelectorAll("option:checked").forEach(option => {
        const cardId = option.value;
        const quantity = option.getAttribute("data-quantity") || "1";
        const hiddenInput = document.createElement("input");
        hiddenInput.type = "hidden";
        hiddenInput.name = originalFieldName;
        hiddenInput.value = `${cardId}:${quantity}`;
        hiddenInput.setAttribute("data-generated-for-card-multiselect", originalFieldName);
        form.appendChild(hiddenInput);
      });

      // Prevent the browser from submitting the select field directly.
      selectField.removeAttribute("name");
    });
  }

  /**
   * Reset stale selections in all card multiselect fields.
   * This is triggered on the window's 'pageshow' event to clear any lingering selections.
   */
  function resetCardMultiselectState() {
    const multiselectFields = document.querySelectorAll("select.card-multiselect");
    multiselectFields.forEach(selectField => {
      // Deselect all options.
      selectField.querySelectorAll("option").forEach(option => {
        option.selected = false;
      });

      // If the select field has an associated Choices.js instance, clear its selection.
      if (selectField.choicesInstance) {
        const activeSelections = selectField.choicesInstance.getValue(true);
        if (activeSelections.length > 0) {
          selectField.choicesInstance.removeActiveItemsByValue(activeSelections);
        }
        selectField.choicesInstance.setValue([]);
      }
    });
  }

  // On DOMContentLoaded, initialize theme toggling and form processing.
  document.addEventListener("DOMContentLoaded", () => {
    initThemeToggle();
    initCardMultiselectHandling();
  });

  // On pageshow, only reset multiselect state if the page was loaded from bfcache.
  window.addEventListener("pageshow", function(event) {
    if (event.persisted) {
      resetCardMultiselectState();
    }
  });

  // Expose tradeOfferCard globally if not already defined.
  if (!window.tradeOfferCard) {
    window.tradeOfferCard = function() {
      return {
        flipped: false,
        badgeExpanded: false,
        acceptanceExpanded: false,
        /**
         * Update the badge's expanded state.
         *
         * @param {boolean} expanded - The new state of the badge.
         */
        setBadge(expanded) {
          this.badgeExpanded = expanded;
        },
      };
    };
  }
})();