final: refactor for removal of system package and reduction of interactions to state package

State query command has been moved to main where it belongs, "system" information are now fetched in app.New and stored in *App with accessors for relevant values. Exit (cleanup-related) functions are separated into its dedicated "final" package.

Signed-off-by: Ophestra Umiker <cat@ophivana.moe>

internal/final/exit.go

@@ -0,0 +1,73 @@
+package final
+
+import (
+	"errors"
+	"fmt"
+	"git.ophivana.moe/cat/fortify/internal/acl"
+	"git.ophivana.moe/cat/fortify/internal/state"
+	"git.ophivana.moe/cat/fortify/internal/verbose"
+	"git.ophivana.moe/cat/fortify/internal/xcb"
+	"io/fs"
+	"os"
+)
+
+func Fatal(msg ...any) {
+	fmt.Println(msg...)
+	BeforeExit()
+	os.Exit(1)
+}
+
+func BeforeExit() {
+	if u == nil {
+		fmt.Println("warn: beforeExit called before app init")
+		return
+	}
+
+	if statePath == "" {
+		verbose.Println("State path is unset")
+	} else {
+		if err := os.Remove(statePath); err != nil && !errors.Is(err, fs.ErrNotExist) {
+			fmt.Println("Error removing state file:", err)
+		}
+	}
+
+	if d, err := state.ReadLaunchers(runDirPath, u.Uid); err != nil {
+		fmt.Println("Error reading active launchers:", err)
+		os.Exit(1)
+	} else if len(d) > 0 {
+		// other launchers are still active
+		verbose.Printf("Found %d active launchers, exiting without cleaning up\n", len(d))
+		return
+	}
+
+	verbose.Println("No other launchers active, will clean up")
+
+	if xcbActionComplete {
+		verbose.Printf("X11: Removing XHost entry SI:localuser:%s\n", u.Username)
+		if err := xcb.ChangeHosts(xcb.HostModeDelete, xcb.FamilyServerInterpreted, "localuser\x00"+u.Username); err != nil {
+			fmt.Println("Error removing XHost entry:", err)
+		}
+	}
+
+	for _, candidate := range cleanupCandidate {
+		if err := acl.UpdatePerm(candidate, uid); err != nil {
+			fmt.Printf("Error stripping ACL entry from '%s': %s\n", candidate, err)
+		}
+		verbose.Printf("Stripped ACL entry for user '%s' from '%s'\n", u.Username, candidate)
+	}
+
+	if dbusProxy != nil {
+		verbose.Println("D-Bus proxy registered, cleaning up")
+
+		if err := dbusProxy.Close(); err != nil {
+			if errors.Is(err, os.ErrClosed) {
+				verbose.Println("D-Bus proxy already closed")
+			} else {
+				fmt.Println("Error closing D-Bus proxy:", err)
+			}
+		}
+
+		// wait for Proxy.Wait to return
+		<-*dbusDone
+	}
+}