Prevent duplicate desktop model sessions and record calibration evidence

apps/desktop/src-tauri/src/instance.rs

@@ -0,0 +1,78 @@
+//! Official single-instance transport, scoped to an explicitly selected profile.
+use sha2::{Digest, Sha256};
+use std::{ffi::OsString, io, path::PathBuf};
+use tauri::{Emitter, Manager};
+
+pub fn profile_identifier(base: &str, profile: Option<OsString>) -> io::Result<String> {
+    let Some(profile) = profile else {
+        return Ok(base.to_owned());
+    };
+    let path = crate::data_directory::resolve(PathBuf::new(), Some(profile))?;
+    // Resolve the existing ancestor without creating a first-use profile.
+    let canonical = crate::data_directory::canonical_exclusion(&path)?;
+    let mut digest = Sha256::new();
+    #[cfg(windows)]
+    {
+        use std::os::windows::ffi::OsStrExt;
+        for unit in canonical.as_os_str().encode_wide() {
+            digest.update(unit.to_le_bytes());
+        }
+    }
+    #[cfg(not(windows))]
+    {
+        use std::os::unix::ffi::OsStrExt;
+        digest.update(canonical.as_os_str().as_bytes());
+    }
+    Ok(format!("{base}.profile{:x}", digest.finalize()))
+}
+
+pub fn focus_search(app: &tauri::AppHandle) {
+    if let Some(window) = app.get_webview_window("main") {
+        let result = window
+            .show()
+            .and_then(|_| window.unminimize())
+            .and_then(|_| window.set_focus());
+        if let Err(error) = result {
+            eprintln!("Could not focus searchi: {error}");
+        }
+        let _ = window.emit("focus-search", ());
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    #[test]
+    fn default_identity_is_unchanged_and_invalid_profile_rejected() {
+        assert_eq!(
+            profile_identifier("dev.searchi.desktop", None).unwrap(),
+            "dev.searchi.desktop"
+        );
+        assert!(profile_identifier("dev.searchi.desktop", Some("relative".into())).is_err());
+    }
+    #[test]
+    fn canonical_profiles_are_stable_distinct_and_do_not_expose_paths() {
+        let root = tempfile::tempdir().unwrap();
+        let first = root.path().join("Gemäß_日本_😀");
+        let second = root.path().join("other");
+        let id = profile_identifier("dev.searchi.desktop", Some(first.clone().into_os_string()))
+            .unwrap();
+        assert!(!first.exists());
+        std::fs::create_dir(&first).unwrap();
+        assert_eq!(
+            id,
+            profile_identifier(
+                "dev.searchi.desktop",
+                Some(first.join(".").into_os_string())
+            )
+            .unwrap()
+        );
+        assert_ne!(
+            id,
+            profile_identifier("dev.searchi.desktop", Some(second.into_os_string())).unwrap()
+        );
+        assert!(!id.contains("Gemäß"));
+        assert_eq!(id.len(), "dev.searchi.desktop.profile".len() + 64);
+        assert!(!root.path().join("other").exists());
+    }
+}