From 5c36a7379aacdffd38086f5672a1b965059f5d89 Mon Sep 17 00:00:00 2001
From: Wojciech Kozlowski <wk@wojciechkozlowski.eu>
Date: Mon, 5 Feb 2024 23:40:02 +0100
Subject: [PATCH] Use saturating add/sub

---
 src/tui/app/selection.rs | 32 ++++++++++++++++----------------
 src/tui/ui.rs            |  2 +-
 2 files changed, 17 insertions(+), 17 deletions(-)

diff --git a/src/tui/app/selection.rs b/src/tui/app/selection.rs
index 629f935..6438bd0 100644
--- a/src/tui/app/selection.rs
+++ b/src/tui/app/selection.rs
@@ -56,7 +56,7 @@ impl Delta {
     fn as_usize(&self, state: &WidgetState) -> usize {
         match self {
             Delta::Line => 1,
-            Delta::Page => state.height.checked_sub(1).unwrap_or(0),
+            Delta::Page => state.height.saturating_sub(1),
         }
     }
 }
@@ -174,10 +174,10 @@ impl ArtistSelection {
 
     fn increment_by(&mut self, artists: &[Artist], by: usize) {
         if let Some(index) = self.state.list.selected() {
-            let result = index
-                .checked_add(by)
-                .filter(|i| i < &artists.len())
-                .unwrap_or_else(|| artists.len() - 1);
+            let mut result = index.saturating_add(by);
+            if result >= artists.len() {
+                result = artists.len() - 1;
+            }
             if self.state.list.selected() != Some(result) {
                 self.state.list.select(Some(result));
                 self.album = AlbumSelection::initialise(&artists[result].albums);
@@ -203,7 +203,7 @@ impl ArtistSelection {
 
     fn decrement_by(&mut self, artists: &[Artist], by: usize) {
         if let Some(index) = self.state.list.selected() {
-            let result = index.checked_sub(by).unwrap_or(0);
+            let result = index.saturating_sub(by);
             if self.state.list.selected() != Some(result) {
                 self.state.list.select(Some(result));
                 self.album = AlbumSelection::initialise(&artists[result].albums);
@@ -271,10 +271,10 @@ impl AlbumSelection {
 
     fn increment_by(&mut self, albums: &[Album], by: usize) {
         if let Some(index) = self.state.list.selected() {
-            let result = index
-                .checked_add(by)
-                .filter(|i| i < &albums.len())
-                .unwrap_or_else(|| albums.len() - 1);
+            let mut result = index.saturating_add(by);
+            if result >= albums.len() {
+                result = albums.len() - 1;
+            }
             if self.state.list.selected() != Some(result) {
                 self.state.list.select(Some(result));
                 self.track = TrackSelection::initialise(&albums[result].tracks);
@@ -294,7 +294,7 @@ impl AlbumSelection {
 
     fn decrement_by(&mut self, albums: &[Album], by: usize) {
         if let Some(index) = self.state.list.selected() {
-            let result = index.checked_sub(by).unwrap_or(0);
+            let result = index.saturating_sub(by);
             if self.state.list.selected() != Some(result) {
                 self.state.list.select(Some(result));
                 self.track = TrackSelection::initialise(&albums[result].tracks);
@@ -345,10 +345,10 @@ impl TrackSelection {
 
     fn increment_by(&mut self, tracks: &[Track], by: usize) {
         if let Some(index) = self.state.list.selected() {
-            let result = index
-                .checked_add(by)
-                .filter(|i| i < &tracks.len())
-                .unwrap_or_else(|| tracks.len() - 1);
+            let mut result = index.saturating_add(by);
+            if result >= tracks.len() {
+                result = tracks.len() - 1;
+            }
             if self.state.list.selected() != Some(result) {
                 self.state.list.select(Some(result));
             }
@@ -361,7 +361,7 @@ impl TrackSelection {
 
     fn decrement_by(&mut self, _tracks: &[Track], by: usize) {
         if let Some(index) = self.state.list.selected() {
-            let result = index.checked_sub(by).unwrap_or(0);
+            let result = index.saturating_sub(by);
             if self.state.list.selected() != Some(result) {
                 self.state.list.select(Some(result));
             }
diff --git a/src/tui/ui.rs b/src/tui/ui.rs
index 693959f..e9ba010 100644
--- a/src/tui/ui.rs
+++ b/src/tui/ui.rs
@@ -355,7 +355,7 @@ impl Ui {
             area,
             &mut state.list,
         );
-        state.height = area.height.checked_sub(2).unwrap_or(0) as usize;
+        state.height = area.height.saturating_sub(2) as usize;
     }
 
     fn render_info_widget<B: Backend>(