From c489fef4ff46fc37eb2a7c447a7108afde7ad124 Mon Sep 17 00:00:00 2001
From: Garrick Aden-Buie <garrick@adenbuie.com>
Date: Fri, 27 Sep 2024 10:09:43 -0400
Subject: [PATCH] fix(input_slider): Make sure last used handle is always above
 others (#4131)

---
 NEWS.md                                                   | 8 ++++++--
 inst/www/shared/ionrangeslider/css/ion.rangeSlider.css    | 4 ++++
 inst/www/shared/ionrangeslider/scss/shiny.scss            | 5 +++++
 .../0001-Add-skin-customized-for-Shiny.patch              | 7 ++++++-
 4 files changed, 21 insertions(+), 3 deletions(-)

diff --git a/NEWS.md b/NEWS.md
index ff1a3900c1..30dd6c1742 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -4,14 +4,18 @@
 
 * Small improvements to the default pulse busy indicator to better blend with any background. It's also now slightly smaller by default. (#4122)
 
+## Bug fixes
+
+* Fixed a bug in `conditionalPanel()` that would cause the panel to repeatedly show/hide itself when the provided condition was not boolean. (@kamilzyla, #4127)
+
+* Fixed a bug with `input_slider()` when used as a range slider that made it impossible to change the slider value when both handles were at the maximum value. (#4131)
+
 # shiny 1.9.1
 
 ## Bug fixes
 
 * Fixed a bug introduced in v1.9.0 where the boundaries of hover/click/brush regions on plots were being incorrectly scaled when browser zoom was used. (#4111)
 
-* Fixed a bug in `conditionalPanel()` that would cause the panel to repeatedly show/hide itself when the provided condition was not boolean. (@kamilzyla, #4127)
-
 # shiny 1.9.0
 
 ## New busy indication feature
diff --git a/inst/www/shared/ionrangeslider/css/ion.rangeSlider.css b/inst/www/shared/ionrangeslider/css/ion.rangeSlider.css
index 5b1a8f4b4a..a95e944a18 100644
--- a/inst/www/shared/ionrangeslider/css/ion.rangeSlider.css
+++ b/inst/www/shared/ionrangeslider/css/ion.rangeSlider.css
@@ -235,6 +235,10 @@
   z-index: 2;
 }
 
+.irs--shiny .irs-handle.type_last {
+  z-index: 3;
+}
+
 .irs--shiny .irs-handle.state_hover, .irs--shiny .irs-handle:hover {
   background: #fff;
 }
diff --git a/inst/www/shared/ionrangeslider/scss/shiny.scss b/inst/www/shared/ionrangeslider/scss/shiny.scss
index 72203cc230..c882844622 100644
--- a/inst/www/shared/ionrangeslider/scss/shiny.scss
+++ b/inst/www/shared/ionrangeslider/scss/shiny.scss
@@ -143,6 +143,11 @@ $font-family: $font-family-base !default;
     border-radius: $handle_width;
     z-index: 2;
 
+    &.type_last {
+      // Ensure last-used handle is on top if it overlaps with another handle
+      z-index: 3;
+    }
+
     &.state_hover,
     &:hover {
       background: $handle_color_hover;
diff --git a/tools/ion.rangeSlider-patches/0001-Add-skin-customized-for-Shiny.patch b/tools/ion.rangeSlider-patches/0001-Add-skin-customized-for-Shiny.patch
index 185f3a56bc..d9bb9f5aec 100644
--- a/tools/ion.rangeSlider-patches/0001-Add-skin-customized-for-Shiny.patch
+++ b/tools/ion.rangeSlider-patches/0001-Add-skin-customized-for-Shiny.patch
@@ -3,7 +3,7 @@ new file mode 100644
 index 00000000..ba052f8b
 --- /dev/null
 +++ b/inst/www/shared/ionrangeslider/scss/shiny.scss
-@@ -0,0 +1,201 @@
+@@ -0,0 +1,206 @@
 +/* 'shiny' skin for Ion.RangeSlider, largely based on the 'big' skin, but with smaller dimensions, grayscale grid text, and without gradients
 +© Posit, PBC, 2023
 +© RStudio, Inc, 2014
@@ -149,6 +149,11 @@ index 00000000..ba052f8b
 +    border-radius: $handle_width;
 +    z-index: 2;
 +
++    &.type_last {
++      // Ensure last-used handle is on top if it overlaps with another handle
++      z-index: 3;
++    }
++
 +    &.state_hover,
 +    &:hover {
 +      background: $handle_color_hover;