From 756b91cd087c68c1997f1d43f0f6b428fa12112c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Toma=C5=BE=20Hribernik?= <tomaz.hribernik@protonmail.com>
Date: Sat, 7 Oct 2023 13:10:03 +0200
Subject: [PATCH] Add force_reverse_video_selection config

This config option allows selection to behave similarly as the cursor
does when force_reverse_video_cursor config option is set to true. With
this new config set to true, selected text's foreground and background
colors are swapped. Addresses issue #3440
---
 config/src/config.rs                          |  3 ++
 wezterm-gui/src/termwindow/render/mod.rs      |  8 +++-
 .../src/termwindow/render/screen_line.rs      | 47 ++++++++++++++++++-
 3 files changed, 55 insertions(+), 3 deletions(-)

diff --git a/config/src/config.rs b/config/src/config.rs
index 19d5b9c81..f4c46493f 100644
--- a/config/src/config.rs
+++ b/config/src/config.rs
@@ -599,6 +599,9 @@ pub struct Config {
     #[dynamic(default)]
     pub force_reverse_video_cursor: bool,
 
+    #[dynamic(default)]
+    pub force_reverse_video_selection: bool,
+
     /// Specifies the default cursor style.  various escape sequences
     /// can override the default style in different situations (eg:
     /// an editor can change it depending on the mode), but this value
diff --git a/wezterm-gui/src/termwindow/render/mod.rs b/wezterm-gui/src/termwindow/render/mod.rs
index b4266e9f2..fe21c8875 100644
--- a/wezterm-gui/src/termwindow/render/mod.rs
+++ b/wezterm-gui/src/termwindow/render/mod.rs
@@ -579,11 +579,15 @@ impl crate::TermWindow {
             visibility,
         ) {
             // Selected text overrides colors
-            (true, _, _, CursorVisibility::Hidden) => (
+            (true, _, _, CursorVisibility::Hidden) => if self.config.force_reverse_video_selection {(
+                params.bg_color,
+                params.fg_color,
+                params.cursor_bg,
+            )} else {(
                 params.selection_fg.when_fully_transparent(params.fg_color),
                 params.selection_bg,
                 params.cursor_bg,
-            ),
+            )},
             // block Cursor cell overrides colors
             (
                 _,
diff --git a/wezterm-gui/src/termwindow/render/screen_line.rs b/wezterm-gui/src/termwindow/render/screen_line.rs
index b7d4daa4f..6a639dfef 100644
--- a/wezterm-gui/src/termwindow/render/screen_line.rs
+++ b/wezterm-gui/src/termwindow/render/screen_line.rs
@@ -11,6 +11,7 @@ use config::{HsbTransform, TextStyle};
 use std::ops::Range;
 use std::rc::Rc;
 use std::time::Instant;
+use std::cmp::{max, min};
 use termwiz::cell::{unicode_column_width, Blink};
 use termwiz::color::LinearRgba;
 use wezterm_bidi::Direction;
@@ -288,17 +289,61 @@ impl crate::TermWindow {
         let selection_pixel_range = if !params.selection.is_empty() {
             let start = params.left_pixel_x + (params.selection.start as f32 * cell_width);
             let width = (params.selection.end - params.selection.start) as f32 * cell_width;
+
+            // When using reverse video, we draw the selection rectangle with
+            // text foreground as its color
+            let selection_color = if self.config.force_reverse_video_selection {
+                params.foreground
+            } else {
+                params.selection_bg
+            };
+
             let mut quad = self
                 .filled_rectangle(
                     layers,
                     0,
                     euclid::rect(start, params.top_pixel_y, width, cell_height),
-                    params.selection_bg,
+                    selection_color,
                 )
                 .context("filled_rectangle")?;
 
             quad.set_hsv(hsv);
 
+            // When using reverse video selection, we also draw a selection
+            // rectangle for each item with a different foreground color than
+            // the default one
+            if self.config.force_reverse_video_selection {
+                for item in shaped.iter() {
+                    let cluster = &item.cluster;
+
+                    if !item.fg_color.eq(&params.foreground) {
+                        // Calculate the number of item's cells actually inside
+                        // the selection
+                        let left = max(cluster.first_cell_idx, params.selection.start);
+                        let right = min(cluster.first_cell_idx + cluster.width, params.selection.end);
+
+                        // Only draw a rectangle for items with selected cells
+                        if right > left {
+                            // log::error!("Drawing A rectangle {} {}", left, right);
+                            let mut quad = self
+                                .filled_rectangle(
+                                    layers,
+                                    0,
+                                    euclid::rect(
+                                        params.left_pixel_x + (left as f32 * cell_width),
+                                        params.top_pixel_y,
+                                        (right - left) as f32 * cell_width,
+                                        cell_height
+                                    ),
+                                    item.fg_color,
+                                )
+                                .context("filled_rectangle")?;
+                            quad.set_hsv(hsv);
+                        }
+                    }
+                }
+            }
+
             start..start + width
         } else {
             0.0..0.0