From d70be55f708fdae8c6e89cae1ad48a35d716bf10 Mon Sep 17 00:00:00 2001
From: wojciechkepka <wojtek.kepka@protonmail.com>
Date: Sun, 20 Jun 2021 22:02:41 +0200
Subject: [PATCH] Add ability to theme primary selecition

---
 book/src/themes.md          |  1 +
 helix-term/src/ui/editor.rs | 25 ++++++++++++++++++-------
 theme.toml                  |  3 ++-
 3 files changed, 21 insertions(+), 8 deletions(-)

diff --git a/book/src/themes.md b/book/src/themes.md
index d552f41af..01fda34a6 100644
--- a/book/src/themes.md
+++ b/book/src/themes.md
@@ -89,6 +89,7 @@ Possible keys:
 | `ui.text.focus`          |                                     |
 | `ui.menu.selected`       |                                     |
 | `ui.selection`           | For selections in the editing area  |
+| `ui.selection.primary`   |                                     |
 | `warning`                | LSP warning                         |
 | `error`                  | LSP error                           |
 | `info`                   | LSP info                            |
diff --git a/helix-term/src/ui/editor.rs b/helix-term/src/ui/editor.rs
index 43f1069d7..06f7e644c 100644
--- a/helix-term/src/ui/editor.rs
+++ b/helix-term/src/ui/editor.rs
@@ -294,16 +294,27 @@ impl EditorView {
             });
 
             let selection_style = theme.get("ui.selection");
+            let primary_style = theme
+                .try_get("ui.selection.primary")
+                .unwrap_or(selection_style);
+            let selection = doc.selection(view.id);
+            let primary_idx = selection.primary_index();
 
-            for selection in doc
-                .selection(view.id)
+            for (i, selection) in selection
                 .iter()
-                .filter(|range| range.overlaps(&screen))
+                .enumerate()
+                .filter(|(_, range)| range.overlaps(&screen))
             {
                 // TODO: render also if only one of the ranges is in viewport
                 let mut start = view.screen_coords_at_pos(doc, text, selection.anchor);
                 let mut end = view.screen_coords_at_pos(doc, text, selection.head);
 
+                let style = if i != primary_idx {
+                    selection_style
+                } else {
+                    primary_style
+                };
+
                 let head = end;
 
                 if selection.head < selection.anchor {
@@ -331,7 +342,7 @@ impl EditorView {
                             ),
                             1,
                         ),
-                        selection_style,
+                        style,
                     );
                 } else {
                     surface.set_style(
@@ -342,7 +353,7 @@ impl EditorView {
                             viewport.width.saturating_sub(start.col as u16),
                             1,
                         ),
-                        selection_style,
+                        style,
                     );
                     for i in start.row + 1..end.row {
                         surface.set_style(
@@ -353,7 +364,7 @@ impl EditorView {
                                 viewport.width,
                                 1,
                             ),
-                            selection_style,
+                            style,
                         );
                     }
                     surface.set_style(
@@ -363,7 +374,7 @@ impl EditorView {
                             (end.col as u16).min(viewport.width),
                             1,
                         ),
-                        selection_style,
+                        style,
                     );
                 }
 
diff --git a/theme.toml b/theme.toml
index a4f402675..6c357ef47 100644
--- a/theme.toml
+++ b/theme.toml
@@ -52,7 +52,8 @@
 "ui.text" = { fg = "#a4a0e8" } # lavender
 "ui.text.focus" = { fg = "#dbbfef"} # lilac
 
-"ui.selection" = { bg = "#540099" }
+"ui.selection" = { bg = "#44258b" }
+"ui.selection.primary" = { bg = "#540099" }
 "ui.menu.selected" = { fg = "#281733", bg = "#ffffff" } # revolver
 
 "warning" = "#ffcd1c"