end to end tests for the game page

client/src/modules/front_end_components/ModalManager.js

@@ -0,0 +1,34 @@
+export const ModalManager = {
+    displayModal: displayModal,
+    dispelModal: dispelModal
+};
+
+function displayModal (modalId, backgroundId, closeButtonId) {
+    const modal = document.getElementById(modalId);
+    const modalOverlay = document.getElementById(backgroundId);
+    const closeBtn = document.getElementById(closeButtonId);
+    let closeModalHandler;
+    if (modal && modalOverlay && closeBtn) {
+        modal.style.display = 'flex';
+        modalOverlay.style.display = 'flex';
+        modalOverlay.removeEventListener('click', closeModalHandler);
+        modalOverlay.addEventListener('click', closeModalHandler = function (e) {
+            e.preventDefault();
+            dispelModal(modalId, backgroundId);
+        });
+        closeBtn.removeEventListener('click', closeModalHandler);
+        closeBtn.addEventListener('click', closeModalHandler);
+    } else {
+        throw new Error('One or more of the ids supplied to ModalManager.displayModal is invalid.');
+    }
+    modal.focus();
+}
+
+function dispelModal (modalId, backgroundId) {
+    const modal = document.getElementById(modalId);
+    const modalOverlay = document.getElementById(backgroundId);
+    if (modal && modalOverlay) {
+        modal.style.display = 'none';
+        modalOverlay.style.display = 'none';
+    }
+}