Auto-update: download + install + restart

- CheckForUpdates binding returns version string if newer available
- InstallUpdate binding downloads zip, extracts, replaces app, restarts
- checkUpdates goroutine polls every 6h, shows dialog with version
- make install copies .app to /Applications
- Update script: quit app → sleep → replace .app → relaunch

cmd/desktop/main.go

@@ -478,41 +478,168 @@ type giteaRelease struct {
 	} `json:"assets"`
 }
 
+type updateState struct {
+	mu        sync.Mutex
+	latestURL string
+}
+
+var updater = &updateState{}
+
+// CheckForUpdates checks Gitea releases for a newer version. If found, stores
+// the download URL and returns the latest version string (empty if current).
+func (c *ConfigService) CheckForUpdates() string {
+	latest := fetchLatestRelease()
+	if latest == nil || latest.Version == version {
+		return ""
+	}
+	for _, a := range latest.Assets {
+		if strings.Contains(a.Name, "darwin") {
+			updater.mu.Lock()
+			updater.latestURL = a.BrowserDownloadURL
+			updater.mu.Unlock()
+			return latest.Version
+		}
+	}
+	return ""
+}
+
+// InstallUpdate downloads the stored update, replaces the app, and restarts.
+func (c *ConfigService) InstallUpdate() error {
+	updater.mu.Lock()
+	url := updater.latestURL
+	updater.mu.Unlock()
+	if url == "" {
+		return fmt.Errorf("no update available")
+	}
+	return doUpdate(url)
+}
+
+type latestRelease struct {
+	Version string
+	Assets  []struct {
+		Name               string
+		BrowserDownloadURL string
+	}
+}
+
+func fetchLatestRelease() *latestRelease {
+	resp, err := http.Get(updateURL + "?draft=false&pre-release=false&limit=1")
+	if err != nil {
+		return nil
+	}
+	defer resp.Body.Close()
+
+	var releases []giteaRelease
+	if err := json.NewDecoder(resp.Body).Decode(&releases); err != nil || len(releases) == 0 {
+		return nil
+	}
+
+	r := releases[0]
+	v := strings.TrimPrefix(r.TagName, "v")
+	if v == version {
+		return nil
+	}
+
+	lr := &latestRelease{Version: v}
+	for _, a := range r.Assets {
+		lr.Assets = append(lr.Assets, struct {
+			Name               string
+			BrowserDownloadURL string
+		}{a.Name, a.BrowserDownloadURL})
+	}
+	return lr
+}
+
+func doUpdate(downloadURL string) error {
+	tmp, err := os.CreateTemp("", "oikos-update-*.zip")
+	if err != nil {
+		return err
+	}
+	defer os.Remove(tmp.Name())
+
+	resp, err := http.Get(downloadURL)
+	if err != nil {
+		return err
+	}
+	defer resp.Body.Close()
+
+	if _, err := io.Copy(tmp, resp.Body); err != nil {
+		return err
+	}
+	tmp.Close()
+
+	extractDir, err := os.MkdirTemp("", "oikos-extract")
+	if err != nil {
+		return err
+	}
+	defer os.RemoveAll(extractDir)
+
+	cmd := exec.Command("unzip", "-o", tmp.Name(), "-d", extractDir)
+	if out, err := cmd.CombinedOutput(); err != nil {
+		return fmt.Errorf("unzip: %w: %s", err, out)
+	}
+
+	newApp := filepath.Join(extractDir, "oikos-desktop.app")
+	if _, err := os.Stat(newApp); err != nil {
+		return fmt.Errorf("extracted app not found: %w", err)
+	}
+
+	currentApp := "/Applications/oikos-desktop.app"
+	if _, err := os.Stat(currentApp); os.IsNotExist(err) {
+		if exe, err := os.Executable(); err == nil {
+			currentApp = filepath.Dir(filepath.Dir(filepath.Dir(exe)))
+		}
+	}
+
+	script := fmt.Sprintf(`#!/bin/bash
+sleep 2
+rm -rf "%s"
+mv "%s" "%s"
+open "%s"
+rm "$0"
+`, currentApp, newApp, currentApp, currentApp)
+
+	scriptPath := filepath.Join(os.TempDir(), "oikos-update.sh")
+	if err := os.WriteFile(scriptPath, []byte(script), 0755); err != nil {
+		return err
+	}
+
+	app := application.Get()
+	exec.Command("open", scriptPath).Start()
+	if app != nil {
+		app.Quit()
+	}
+
+	return nil
+}
+
 func checkUpdates() {
 	for {
-		resp, err := http.Get(updateURL + "?draft=false&pre-release=false&limit=1")
-		if err != nil {
-			time.Sleep(updateInterval)
-			continue
-		}
-		body, _ := io.ReadAll(resp.Body)
-		resp.Body.Close()
-
-		var releases []giteaRelease
-		if err := json.Unmarshal(body, &releases); err != nil || len(releases) == 0 {
-			time.Sleep(updateInterval)
-			continue
-		}
-
-		latest := releases[0]
-		latestVersion := strings.TrimPrefix(latest.TagName, "v")
-		if latestVersion == version {
-			time.Sleep(updateInterval)
-			continue
-		}
-
-		app := application.Get()
-		if app == nil {
-			time.Sleep(updateInterval)
-			continue
-		}
-
-		msg := fmt.Sprintf("Version %s is available (you have %s). Download from Gitea releases.", latestVersion, version)
-		app.Dialog.Info().
-			SetTitle("Update Available").
-			SetMessage(msg).
-			Show()
 		time.Sleep(updateInterval)
+
+		latest := fetchLatestRelease()
+		if latest == nil {
+			continue
+		}
+
+		for _, a := range latest.Assets {
+			if strings.Contains(a.Name, "darwin") {
+				updater.mu.Lock()
+				updater.latestURL = a.BrowserDownloadURL
+				updater.mu.Unlock()
+
+				app := application.Get()
+				if app == nil {
+					continue
+				}
+				msg := fmt.Sprintf("Version %s is available (you have %s).", latest.Version, version)
+				app.Dialog.Info().
+					SetTitle("Update Available").
+					SetMessage(msg).
+					Show()
+				break
+			}
+		}
 	}
 }