Feature: add Google Drive backup and restore integration

app.js

@@ -46,6 +46,10 @@ const backupBtn = document.getElementById("backupBtn");
 const restoreMergeBtn = document.getElementById("restoreMergeBtn");
 const restoreReplaceBtn = document.getElementById("restoreReplaceBtn");
 const restoreFileInput = document.getElementById("restoreFileInput");
+const googleDriveState = document.getElementById("googleDriveState");
+const googleConnectBtn = document.getElementById("googleConnectBtn");
+const googleBackupBtn = document.getElementById("googleBackupBtn");
+const googleRestoreBtn = document.getElementById("googleRestoreBtn");
 const quickSearchInput = document.getElementById("quickSearchInput");
 const quickSearchResults = document.getElementById("quickSearchResults");
 const gamesList = document.getElementById("gamesList");
@@ -53,6 +57,7 @@ const gameCardTemplate = document.getElementById("gameCardTemplate");
 let editingGameId = null;
 let pendingRestoreMode = "merge";
 let quickSearchTerm = "";
+let googleStatus = { configured: false, connected: false, email: "" };
 
 toolsToggleBtn.addEventListener("click", () => {
   toolsDrawer.classList.toggle("open");
@@ -81,6 +86,48 @@ document.addEventListener("keydown", (event) => {
   }
 });
 
+googleConnectBtn.addEventListener("click", async () => {
+  try {
+    const payload = await apiRequest("/api/google/connect-url");
+    if (!payload.url) {
+      throw new Error("Missing Google connect URL");
+    }
+    window.location.href = payload.url;
+  } catch (error) {
+    console.error(error);
+    alert("Connexion Google indisponible. Verifie la configuration OAuth.");
+  }
+});
+
+googleBackupBtn.addEventListener("click", async () => {
+  try {
+    const payload = await apiRequest("/api/google/backup/upload", { method: "POST" });
+    await refreshGoogleStatus();
+    alert(`Sauvegarde Drive OK: ${payload.fileName || "fichier cree"}.`);
+  } catch (error) {
+    console.error(error);
+    alert("Echec sauvegarde Google Drive.");
+  }
+});
+
+googleRestoreBtn.addEventListener("click", async () => {
+  const confirmed = window.confirm("Restaurer depuis le dernier backup Google Drive ?");
+  if (!confirmed) {
+    return;
+  }
+  try {
+    const payload = await apiRequest("/api/google/backup/restore", {
+      method: "POST",
+      body: { mode: "merge" },
+    });
+    await refreshFromApi(state.selectedBrand, state.selectedConsole);
+    alert(`Restauration Drive OK (${payload.mode})`);
+  } catch (error) {
+    console.error(error);
+    alert("Echec restauration Google Drive.");
+  }
+});
+
 quickSearchInput.addEventListener("input", (event) => {
   quickSearchTerm = event.target.value.trim();
   renderSearchResults();
@@ -435,6 +482,7 @@ restoreFileInput.addEventListener("change", async (event) => {
 
 function render() {
   renderDataMode();
+  renderGoogleStatus();
   renderBrandTabs();
   renderConsoleTabs();
   renderGames();
@@ -491,6 +539,34 @@ function renderDataMode() {
   }
 }
 
+function renderGoogleStatus() {
+  if (!googleDriveState) {
+    return;
+  }
+
+  if (!googleStatus.configured) {
+    googleDriveState.textContent = "Etat Google Drive: non configure (OAuth manquant).";
+    googleConnectBtn.disabled = true;
+    googleBackupBtn.disabled = true;
+    googleRestoreBtn.disabled = true;
+    return;
+  }
+
+  if (!googleStatus.connected) {
+    googleDriveState.textContent = "Etat Google Drive: non connecte.";
+    googleConnectBtn.disabled = false;
+    googleBackupBtn.disabled = true;
+    googleRestoreBtn.disabled = true;
+    return;
+  }
+
+  const email = googleStatus.email ? ` (${googleStatus.email})` : "";
+  googleDriveState.textContent = `Etat Google Drive: connecte${email}.`;
+  googleConnectBtn.disabled = false;
+  googleBackupBtn.disabled = false;
+  googleRestoreBtn.disabled = false;
+}
+
 function findBrandByConsole(consoleName) {
   for (const [brand, consoles] of Object.entries(state.brands)) {
     if (Array.isArray(consoles) && consoles.includes(consoleName)) {
@@ -829,6 +905,15 @@ async function refreshFromApi(preferredBrand, preferredConsole) {
   render();
 }
 
+async function refreshGoogleStatus() {
+  try {
+    googleStatus = await apiRequest("/api/google/status");
+  } catch {
+    googleStatus = { configured: false, connected: false, email: "" };
+  }
+  renderGoogleStatus();
+}
+
 async function hydrateFromApi() {
   try {
     await refreshFromApi(state.selectedBrand, state.selectedConsole);
@@ -839,9 +924,29 @@ async function hydrateFromApi() {
 }
 
 async function bootstrap() {
+  await refreshGoogleStatus();
   await hydrateFromApi();
   normalizeState();
   render();
+  handleGoogleCallbackResult();
 }
 
 bootstrap();
+
+function handleGoogleCallbackResult() {
+  const url = new URL(window.location.href);
+  const googleParam = url.searchParams.get("google");
+  if (!googleParam) {
+    return;
+  }
+
+  if (googleParam === "connected") {
+    alert("Google Drive connecte avec succes.");
+    refreshGoogleStatus();
+  } else if (googleParam === "error") {
+    alert("Connexion Google Drive echouee.");
+  }
+
+  url.searchParams.delete("google");
+  window.history.replaceState({}, "", url.toString());
+}