From a54fbf7f63a2aa16dc37cb964dae6406b040143a Mon Sep 17 00:00:00 2001
From: Stephan Dilly <dilly.stephan@gmail.com>
Date: Sat, 18 Jul 2020 12:21:18 +0200
Subject: [PATCH] visualize pending load of a diff (#160)

---
 CHANGELOG.md                     |  1 +
 src/components/diff.rs           | 28 +++++++++++++++++++---------
 src/components/inspect_commit.rs |  4 +++-
 src/strings.rs                   |  2 ++
 src/tabs/status.rs               |  4 ++--
 5 files changed, 27 insertions(+), 12 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index f64daab5..b14a97d7 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,6 +7,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ## [Unreleased]
 
 ### Added
+- pending load of a diff is visualized better ([#160](https://github.com/extrawurst/gitui/issues/160))
 - entry on [git-scm.com](https://git-scm.com/downloads/guis) in the list of GUI tools [[@Vidar314](https://github.com/Vidar314)] (see [PR](https://github.com/git/git-scm.com/pull/1485))
 - commits can be tagged in revlog [[@cruessler](https://github.com/cruessler)] ([#103](https://github.com/extrawurst/gitui/issues/103))
 
diff --git a/src/components/diff.rs b/src/components/diff.rs
index 110031b7..868806b3 100644
--- a/src/components/diff.rs
+++ b/src/components/diff.rs
@@ -12,7 +12,7 @@ use crossterm::event::Event;
 use std::{borrow::Cow, cell::Cell, cmp, path::Path};
 use tui::{
     backend::Backend,
-    layout::{Alignment, Rect},
+    layout::Rect,
     symbols,
     widgets::{Block, Borders, Paragraph, Text},
     Frame,
@@ -30,6 +30,7 @@ struct Current {
 ///
 pub struct DiffComponent {
     diff: Option<FileDiff>,
+    pending: bool,
     selection: usize,
     selected_hunk: Option<usize>,
     current_size: Cell<(u16, u16)>,
@@ -47,6 +48,7 @@ impl DiffComponent {
             focused: false,
             queue,
             current: Current::default(),
+            pending: false,
             selected_hunk: None,
             diff: None,
             current_size: Cell::new((0, 0)),
@@ -67,12 +69,13 @@ impl DiffComponent {
         (self.current.path.clone(), self.current.is_stage)
     }
     ///
-    pub fn clear(&mut self) -> Result<()> {
+    pub fn clear(&mut self, pending: bool) -> Result<()> {
         self.current = Current::default();
         self.diff = None;
         self.scroll_top.set(0);
         self.selection = 0;
         self.selected_hunk = None;
+        self.pending = pending;
 
         Ok(())
     }
@@ -83,6 +86,8 @@ impl DiffComponent {
         is_stage: bool,
         diff: FileDiff,
     ) -> Result<()> {
+        self.pending = false;
+
         let hash = hash(&diff);
 
         if self.current.hash != hash {
@@ -432,19 +437,24 @@ impl DrawableComponent for DiffComponent {
 
         let title =
             format!("{}{}", strings::TITLE_DIFF, self.current.path);
+
+        let txt = if self.pending {
+            vec![Text::Styled(
+                Cow::from(strings::LOADING_TEXT),
+                self.theme.text(false, false),
+            )]
+        } else {
+            self.get_text(r.width, self.current_size.get().1)?
+        };
+
         f.render_widget(
-            Paragraph::new(
-                self.get_text(r.width, self.current_size.get().1)?
-                    .iter(),
-            )
-            .block(
+            Paragraph::new(txt.iter()).block(
                 Block::default()
                     .title(title.as_str())
                     .borders(Borders::ALL)
                     .border_style(self.theme.block(self.focused))
                     .title_style(self.theme.title(self.focused)),
-            )
-            .alignment(Alignment::Left),
+            ),
             r,
         );
 
diff --git a/src/components/inspect_commit.rs b/src/components/inspect_commit.rs
index a2201d74..f39d4c09 100644
--- a/src/components/inspect_commit.rs
+++ b/src/components/inspect_commit.rs
@@ -222,10 +222,12 @@ impl InspectCommitComponent {
                     }
 
                     self.git_diff.request(diff_params)?;
+                    self.diff.clear(true)?;
+                    return Ok(());
                 }
             }
 
-            self.diff.clear()?;
+            self.diff.clear(false)?;
         }
 
         Ok(())
diff --git a/src/strings.rs b/src/strings.rs
index 218a5308..509dffb8 100644
--- a/src/strings.rs
+++ b/src/strings.rs
@@ -38,6 +38,8 @@ pub static HELP_TITLE: &str = "Help: all commands";
 pub static STASHING_FILES_TITLE: &str = "Files to Stash";
 pub static STASHING_OPTIONS_TITLE: &str = "Options";
 
+pub static LOADING_TEXT: &str = "Loading ...";
+
 pub mod commit {
     pub static DETAILS_AUTHOR: &str = "Author: ";
     pub static DETAILS_COMMITTER: &str = "Committer: ";
diff --git a/src/tabs/status.rs b/src/tabs/status.rs
index 5de60676..72ba5e39 100644
--- a/src/tabs/status.rs
+++ b/src/tabs/status.rs
@@ -271,11 +271,11 @@ impl Status {
                 {
                     self.diff.update(path, is_stage, diff)?;
                 } else {
-                    self.diff.clear()?;
+                    self.diff.clear(true)?;
                 }
             }
         } else {
-            self.diff.clear()?;
+            self.diff.clear(false)?;
         }
 
         Ok(())