refactor: reduce cognitive complexity and enforce a lint budget

Cargo.toml

@@ -12,7 +12,8 @@ default-run = "wayscriber"
 members = ["configurator"]
 default-members = ["."]
 
-[workspace.lints]
+[workspace.lints.clippy]
+cognitive_complexity = "warn"
 
 [lints]
 workspace = true

clippy.toml

@@ -0,0 +1,3 @@
+# Keep functions within the agreed cognitive-complexity budget. Clippy emits a
+# warning above this value, and CI promotes warnings to errors.
+cognitive-complexity-threshold = 20

src/app/session.rs

@@ -2,23 +2,7 @@ use crate::cli::Cli;
 use crate::env_vars::WAYLAND_DISPLAY_ENV;
 
 pub(crate) fn run_session_cli_commands(cli: &Cli) -> anyhow::Result<()> {
-    if let Some(display_name) = cli.rename_session.as_deref() {
-        let raw_path = cli
-            .session_file
-            .as_ref()
-            .ok_or_else(|| anyhow::anyhow!("--rename-session requires --session-file"))?;
-        let raw = raw_path
-            .to_str()
-            .ok_or_else(|| anyhow::anyhow!("--session-file path must be valid UTF-8"))?;
-        let path = crate::session::normalize_named_session_file_arg(raw);
-        match crate::session::catalog::rename_session_display_name_by_path(&path, display_name)? {
-            Some(entry) => {
-                println!("Renamed session to {}.", entry.display_name);
-            }
-            None => {
-                anyhow::bail!("session is not in the named-session catalog");
-            }
-        }
+    if rename_session(cli)? {
         return Ok(());
     }
 
@@ -62,29 +46,7 @@ pub(crate) fn run_session_cli_commands(cli: &Cli) -> anyhow::Result<()> {
     };
 
     if cli.clear_session {
-        let outcome = crate::session::clear_session(&options)?;
-        println!("Session file: {}", options.session_file_path().display());
-        if outcome.removed_session {
-            println!("  Removed session file");
-        } else {
-            println!("  No session file present");
-        }
-        if outcome.removed_backup {
-            println!("  Removed backup file");
-        }
-        if outcome.removed_recovery {
-            println!("  Removed recovery file");
-        }
-        if outcome.removed_lock {
-            println!("  Removed lock file");
-        }
-        if !outcome.removed_session
-            && !outcome.removed_backup
-            && !outcome.removed_recovery
-            && !outcome.removed_lock
-        {
-            println!("  No session artefacts found");
-        }
+        clear_session(&options)?;
         return Ok(());
     }
 
@@ -189,3 +151,48 @@ pub(crate) fn run_session_cli_commands(cli: &Cli) -> anyhow::Result<()> {
 
     Ok(())
 }
+
+fn rename_session(cli: &Cli) -> anyhow::Result<bool> {
+    let Some(display_name) = cli.rename_session.as_deref() else {
+        return Ok(false);
+    };
+    let raw_path = cli
+        .session_file
+        .as_ref()
+        .ok_or_else(|| anyhow::anyhow!("--rename-session requires --session-file"))?;
+    let raw = raw_path
+        .to_str()
+        .ok_or_else(|| anyhow::anyhow!("--session-file path must be valid UTF-8"))?;
+    let path = crate::session::normalize_named_session_file_arg(raw);
+    let entry = crate::session::catalog::rename_session_display_name_by_path(&path, display_name)?
+        .ok_or_else(|| anyhow::anyhow!("session is not in the named-session catalog"))?;
+    println!("Renamed session to {}.", entry.display_name);
+    Ok(true)
+}
+
+fn clear_session(options: &crate::session::SessionOptions) -> anyhow::Result<()> {
+    let outcome = crate::session::clear_session(options)?;
+    println!("Session file: {}", options.session_file_path().display());
+    if outcome.removed_session {
+        println!("  Removed session file");
+    } else {
+        println!("  No session file present");
+    }
+    if outcome.removed_backup {
+        println!("  Removed backup file");
+    }
+    if outcome.removed_recovery {
+        println!("  Removed recovery file");
+    }
+    if outcome.removed_lock {
+        println!("  Removed lock file");
+    }
+    if !outcome.removed_session
+        && !outcome.removed_backup
+        && !outcome.removed_recovery
+        && !outcome.removed_lock
+    {
+        println!("  No session artefacts found");
+    }
+    Ok(())
+}

src/app/usage.rs

@@ -62,6 +62,16 @@ pub(crate) fn log_overlay_controls(freeze: bool) {
     log::info!("Starting annotation overlay...");
     log::info!("Controls:");
     let bindings = default_action_bindings();
+    log_drawing_controls(&bindings);
+    log_canvas_controls(&bindings);
+    log_ui_controls(&bindings);
+    if freeze {
+        log::info!("Starting frozen mode (freeze-on-start requested)");
+    }
+    log::info!("");
+}
+
+fn log_drawing_controls(bindings: &HashMap<Action, Vec<Shortcut>>) {
     log::info!(
         "  - {}: Just drag",
         action_display_label(Action::SelectPenTool)
@@ -85,77 +95,79 @@ pub(crate) fn log_overlay_controls(freeze: bool) {
     log::info!(
         "  - {}: {}, click to position, type, press Enter",
         action_display_label(Action::EnterTextMode),
-        action_binding_label(&bindings, Action::EnterTextMode)
+        action_binding_label(bindings, Action::EnterTextMode)
     );
-    log::info!("  - Colors: {}", color_binding_labels(&bindings));
+    log::info!("  - Colors: {}", color_binding_labels(bindings));
+}
+
+fn log_canvas_controls(bindings: &HashMap<Action, Vec<Shortcut>>) {
     log::info!(
         "  - {} / {}: {} / {}",
         action_display_label(Action::Undo),
         action_display_label(Action::Redo),
-        action_binding_label(&bindings, Action::Undo),
-        action_binding_label(&bindings, Action::Redo)
+        action_binding_label(bindings, Action::Undo),
+        action_binding_label(bindings, Action::Redo)
     );
     log::info!(
         "  - {}: {}",
         action_display_label(Action::ClearCanvas),
-        action_binding_label(&bindings, Action::ClearCanvas)
+        action_binding_label(bindings, Action::ClearCanvas)
     );
     log::info!(
         "  - {}: {} or scroll down",
         action_display_label(Action::IncreaseThickness),
-        action_binding_label(&bindings, Action::IncreaseThickness)
+        action_binding_label(bindings, Action::IncreaseThickness)
     );
     log::info!(
         "  - {}: {} or scroll up",
         action_display_label(Action::DecreaseThickness),
-        action_binding_label(&bindings, Action::DecreaseThickness)
+        action_binding_label(bindings, Action::DecreaseThickness)
     );
     log::info!(
         "  - {}: {} (toggle frozen background)",
         action_display_label(Action::ToggleFrozenMode),
-        action_binding_label(&bindings, Action::ToggleFrozenMode)
+        action_binding_label(bindings, Action::ToggleFrozenMode)
     );
     log::info!(
         "  - {} / {}: {} / {} (Ctrl+Alt + scroll)",
         action_display_label(Action::ZoomIn),
         action_display_label(Action::ZoomOut),
-        action_binding_label(&bindings, Action::ZoomIn),
-        action_binding_label(&bindings, Action::ZoomOut)
+        action_binding_label(bindings, Action::ZoomIn),
+        action_binding_label(bindings, Action::ZoomOut)
     );
     log::info!(
         "  - {}: {}   •   {}: {}   •   Pan view: middle drag/arrow keys",
         action_display_label(Action::ResetZoom),
-        action_binding_label(&bindings, Action::ResetZoom),
+        action_binding_label(bindings, Action::ResetZoom),
         action_display_label(Action::ToggleZoomLock),
-        action_binding_label(&bindings, Action::ToggleZoomLock)
+        action_binding_label(bindings, Action::ToggleZoomLock)
     );
+}
+
+fn log_ui_controls(bindings: &HashMap<Action, Vec<Shortcut>>) {
     log::info!(
         "  - {}: Right Click or {}",
         action_display_label(Action::OpenContextMenu),
-        action_binding_label(&bindings, Action::OpenContextMenu)
+        action_binding_label(bindings, Action::OpenContextMenu)
     );
     log::info!(
         "  - {}: {}   •   {}: {}   •   {}: {}   •   {}: {}   •   {}: {}",
         action_display_label(Action::ToggleHelp),
-        action_binding_label(&bindings, Action::ToggleHelp),
+        action_binding_label(bindings, Action::ToggleHelp),
         action_display_label(Action::ToggleToolbar),
-        action_binding_label(&bindings, Action::ToggleToolbar),
+        action_binding_label(bindings, Action::ToggleToolbar),
         action_display_label(Action::TogglePresenterMode),
-        action_binding_label(&bindings, Action::TogglePresenterMode),
+        action_binding_label(bindings, Action::TogglePresenterMode),
         action_display_label(Action::OpenConfigurator),
-        action_binding_label(&bindings, Action::OpenConfigurator),
+        action_binding_label(bindings, Action::OpenConfigurator),
         action_display_label(Action::ToggleStatusBar),
-        action_binding_label(&bindings, Action::ToggleStatusBar)
+        action_binding_label(bindings, Action::ToggleStatusBar)
     );
     log::info!(
         "  - {}: {}",
         action_display_label(Action::Exit),
-        action_binding_label(&bindings, Action::Exit)
+        action_binding_label(bindings, Action::Exit)
     );
-    if freeze {
-        log::info!("Starting frozen mode (freeze-on-start requested)");
-    }
-    log::info!("");
 }
 
 pub(crate) fn print_usage() {