From 8b37a22e4dee6ed1220319a8ebd710e7917de999 Mon Sep 17 00:00:00 2001
From: Stephan Dilly <dilly.stephan@gmail.com>
Date: Thu, 19 Mar 2020 21:58:28 +0100
Subject: [PATCH] keep highlighting current diff file

---
 README.md               |  1 -
 src/app.rs              | 18 ++++++++++++------
 src/components/index.rs | 13 ++++++++++++-
 3 files changed, 24 insertions(+), 8 deletions(-)

diff --git a/README.md b/README.md
index cbe719e8..455ba6aa 100644
--- a/README.md
+++ b/README.md
@@ -15,7 +15,6 @@ Over the last 2 years my go-to GUI tool for this was [fork](https://git-fork.com
 * [x] inspect diffs
 * [x] commit
 * [x] [input polling in thread](assets/perf_compare.jpg)
-* [ ] highlight current file being diffed
 * [ ] support non-root git folder wd
 * [ ] show content of new files
 * [ ] indicate file status (modified,added,removed)
diff --git a/src/app.rs b/src/app.rs
index 3e8098c7..e2271091 100644
--- a/src/app.rs
+++ b/src/app.rs
@@ -19,6 +19,7 @@ use tui::{
 };
 
 ///
+#[derive(PartialEq)]
 enum DiffTarget {
     Stage,
     WorkingDir,
@@ -271,26 +272,31 @@ impl App {
 
             match self.focus {
                 Focus::Status => {
-                    self.diff_target = DiffTarget::WorkingDir;
-                    self.index_wd.focus(true);
-                    self.index.focus(false);
+                    self.set_diff_target(DiffTarget::WorkingDir);
                     self.diff.focus(false);
                 }
                 Focus::Stage => {
-                    self.diff_target = DiffTarget::Stage;
-                    self.index.focus(true);
-                    self.index_wd.focus(false);
+                    self.set_diff_target(DiffTarget::Stage);
                     self.diff.focus(false);
                 }
                 Focus::Diff => {
                     self.index.focus(false);
                     self.index_wd.focus(false);
+
                     self.diff.focus(true);
                 }
             };
         }
     }
 
+    fn set_diff_target(&mut self, target: DiffTarget) {
+        self.diff_target = target;
+        let is_stage = self.diff_target == DiffTarget::Stage;
+
+        self.index_wd.focus_select(!is_stage);
+        self.index.focus_select(is_stage);
+    }
+
     fn index_add_remove(&mut self) {
         if self.index_wd.focused() {
             if let Some(i) = self.index_wd.selection() {
diff --git a/src/components/index.rs b/src/components/index.rs
index aa3702a3..c3d4513b 100644
--- a/src/components/index.rs
+++ b/src/components/index.rs
@@ -16,6 +16,7 @@ pub struct IndexComponent {
     index_type: StatusShow,
     selection: Option<usize>,
     focused: bool,
+    show_selection: bool,
 }
 
 impl IndexComponent {
@@ -31,6 +32,7 @@ impl IndexComponent {
             index_type,
             selection: None,
             focused: focus,
+            show_selection: focus,
         }
     }
     ///
@@ -53,6 +55,11 @@ impl IndexComponent {
         }
     }
 
+    pub fn focus_select(&mut self, focus: bool) {
+        self.focus(focus);
+        self.show_selection = focus;
+    }
+
     fn move_selection(&mut self, delta: i32) {
         let items_len = self.items.len();
         if items_len > 0 {
@@ -79,7 +86,11 @@ impl Component for IndexComponent {
                 .map(|e| e.path.clone())
                 .collect::<Vec<_>>()
                 .as_slice(),
-            if self.focused { self.selection } else { None },
+            if self.show_selection {
+                self.selection
+            } else {
+                None
+            },
             self.focused,
         );
     }