fix: gate mango matugen and Cosmic config sync on active session

core/internal/matugen/matugen.go

@@ -47,13 +47,14 @@ type TemplateDef struct {
 	ConfigFile         string
 	Kind               TemplateKind
 	RunUnconditionally bool
+	RequiredEnv        string
 }
 
 var templateRegistry = []TemplateDef{
 	{ID: "gtk", Kind: TemplateKindGTK, RunUnconditionally: true},
 	{ID: "niri", Commands: []string{"niri"}, ConfigFile: "niri.toml"},
 	{ID: "hyprland", Commands: []string{"Hyprland"}, ConfigFile: "hyprland.toml"},
-	{ID: "mangowc", Commands: []string{"mango"}, ConfigFile: "mangowc.toml"},
+	{ID: "mangowc", Commands: []string{"mango"}, ConfigFile: "mangowc.toml", RequiredEnv: "MANGO_INSTANCE_SIGNATURE"},
 	{ID: "qt5ct", Commands: []string{"qt5ct"}, ConfigFile: "qt5ct.toml"},
 	{ID: "qt6ct", Commands: []string{"qt6ct"}, ConfigFile: "qt6ct.toml"},
 	{ID: "firefox", Commands: []string{"firefox"}, ConfigFile: "firefox.toml"},
@@ -356,6 +357,9 @@ output_path = '%s'
 		if opts.ShouldSkipTemplate(tmpl.ID) {
 			continue
 		}
+		if !templateSessionActive(tmpl) {
+			continue
+		}
 
 		switch tmpl.Kind {
 		case TemplateKindGTK:
@@ -489,6 +493,18 @@ func appendTerminalConfig(opts *Options, cfgFile *os.File, tmpDir string, checkC
 	cfgFile.WriteString("\n")
 }
 
+func templateSessionActive(tmpl TemplateDef) bool {
+	if tmpl.RequiredEnv == "" {
+		return true
+	}
+	socket := os.Getenv(tmpl.RequiredEnv)
+	if socket == "" {
+		return false
+	}
+	_, err := os.Stat(socket)
+	return err == nil
+}
+
 func appExists(checker utils.AppChecker, checkCmd []string, checkFlatpaks []string) bool {
 	// Both nil is treated as "skip check" / unconditionally run
 	if checkCmd == nil && checkFlatpaks == nil {
@@ -951,7 +967,7 @@ func CheckTemplates(checker utils.AppChecker) []TemplateCheck {
 		case tmpl.Kind == TemplateKindEmacs:
 			detected = appExists(checker, tmpl.Commands, tmpl.Flatpaks) && utils.EmacsConfigDir() != ""
 		default:
-			detected = appExists(checker, tmpl.Commands, tmpl.Flatpaks)
+			detected = appExists(checker, tmpl.Commands, tmpl.Flatpaks) && templateSessionActive(tmpl)
 		}
 
 		checks = append(checks, TemplateCheck{ID: tmpl.ID, Detected: detected})

core/internal/matugen/matugen_test.go

@@ -441,3 +441,49 @@ func TestBuildMergedConfigColorsOnly(t *testing.T) {
 	assert.NotContains(t, content, "[templates.gtk]")
 	assert.False(t, strings.Contains(content, "output_path = 'CONFIG_DIR/"), "colors-only config should not emit app template outputs")
 }
+
+func TestBuildMergedConfigSkipsMangowcWithoutActiveSession(t *testing.T) {
+	t.Setenv("MANGO_INSTANCE_SIGNATURE", "")
+
+	tempDir := t.TempDir()
+	shellDir := filepath.Join(tempDir, "shell")
+	configsDir := filepath.Join(shellDir, "matugen", "configs")
+	if err := os.MkdirAll(configsDir, 0o755); err != nil {
+		t.Fatalf("failed to create configs dir: %v", err)
+	}
+
+	if err := os.WriteFile(filepath.Join(configsDir, "base.toml"), []byte("[config]\n"), 0o644); err != nil {
+		t.Fatalf("failed to write base config: %v", err)
+	}
+	mangowcConfig := "[templates.dmsmango]\ninput_path = 'in'\noutput_path = 'out'\n"
+	if err := os.WriteFile(filepath.Join(configsDir, "mangowc.toml"), []byte(mangowcConfig), 0o644); err != nil {
+		t.Fatalf("failed to write mangowc config: %v", err)
+	}
+
+	cfgFile, err := os.CreateTemp(tempDir, "merged-*.toml")
+	if err != nil {
+		t.Fatalf("failed to create temp config: %v", err)
+	}
+	defer os.Remove(cfgFile.Name())
+	defer cfgFile.Close()
+
+	opts := &Options{
+		ShellDir:      shellDir,
+		ConfigDir:     filepath.Join(tempDir, "config"),
+		StateDir:      filepath.Join(tempDir, "state"),
+		SkipTemplates: "gtk,niri,hyprland,qt5ct,qt6ct,firefox,pywalfox,zenbrowser,vesktop,vencord,equibop,ghostty,kitty,foot,alacritty,wezterm,nvim,dgop,kcolorscheme,vscode,emacs,zed",
+	}
+
+	if err := buildMergedConfig(opts, cfgFile, filepath.Join(tempDir, "templates")); err != nil {
+		t.Fatalf("buildMergedConfig failed: %v", err)
+	}
+	if err := cfgFile.Close(); err != nil {
+		t.Fatalf("failed to close merged config: %v", err)
+	}
+
+	output, err := os.ReadFile(cfgFile.Name())
+	if err != nil {
+		t.Fatalf("failed to read merged config: %v", err)
+	}
+	assert.NotContains(t, string(output), "[templates.dmsmango]")
+}