Restore update checks and startup notifications

src/main/update.ts

@@ -0,0 +1,67 @@
+import { APP_VERSION, DEFAULT_UPDATE_REPO } from "./constants";
+import { UpdateCheckResult } from "../shared/types";
+import { compactErrorText } from "./utils";
+
+function parseVersionParts(version: string): number[] {
+  const cleaned = version.replace(/^v/i, "").trim();
+  return cleaned.split(".").map((part) => Number(part.replace(/[^0-9].*$/, "") || "0"));
+}
+
+function isRemoteNewer(currentVersion: string, latestVersion: string): boolean {
+  const current = parseVersionParts(currentVersion);
+  const latest = parseVersionParts(latestVersion);
+  const maxLen = Math.max(current.length, latest.length);
+  for (let i = 0; i < maxLen; i += 1) {
+    const a = current[i] ?? 0;
+    const b = latest[i] ?? 0;
+    if (b > a) {
+      return true;
+    }
+    if (b < a) {
+      return false;
+    }
+  }
+  return false;
+}
+
+export async function checkGitHubUpdate(repo: string): Promise<UpdateCheckResult> {
+  const safeRepo = (repo || DEFAULT_UPDATE_REPO).trim() || DEFAULT_UPDATE_REPO;
+  const fallback: UpdateCheckResult = {
+    updateAvailable: false,
+    currentVersion: APP_VERSION,
+    latestVersion: APP_VERSION,
+    latestTag: `v${APP_VERSION}`,
+    releaseUrl: `https://github.com/${safeRepo}/releases/latest`
+  };
+
+  try {
+    const response = await fetch(`https://api.github.com/repos/${safeRepo}/releases/latest`, {
+      headers: {
+        Accept: "application/vnd.github+json",
+        "User-Agent": "RD-Node-Downloader/1.1.14"
+      }
+    });
+    const payload = await response.json().catch(() => null) as Record<string, unknown> | null;
+    if (!response.ok || !payload) {
+      const reason = String((payload?.message as string) || `HTTP ${response.status}`);
+      return { ...fallback, error: reason };
+    }
+
+    const latestTag = String(payload.tag_name || `v${APP_VERSION}`).trim();
+    const latestVersion = latestTag.replace(/^v/i, "") || APP_VERSION;
+    const releaseUrl = String(payload.html_url || fallback.releaseUrl);
+
+    return {
+      updateAvailable: isRemoteNewer(APP_VERSION, latestVersion),
+      currentVersion: APP_VERSION,
+      latestVersion,
+      latestTag,
+      releaseUrl
+    };
+  } catch (error) {
+    return {
+      ...fallback,
+      error: compactErrorText(error)
+    };
+  }
+}