From cf08b088ba481c223b5def47e2e3b4dbfe746dfd Mon Sep 17 00:00:00 2001
From: Guillermo Venegas <guillermovcra@gmail.com>
Date: Thu, 30 Nov 2023 18:26:53 +0100
Subject: [PATCH] Text Editor: Use active text selection as search query

If text is selected, use that as the search query.

Pull Request: https://projects.blender.org/blender/blender/pulls/115247
---
 .../blender/editors/space_text/space_text.cc  | 12 ------
 .../blender/editors/space_text/text_header.cc | 41 ++++++++++++++++---
 source/blender/makesdna/DNA_space_types.h     |  1 -
 3 files changed, 35 insertions(+), 19 deletions(-)

diff --git a/source/blender/editors/space_text/space_text.cc b/source/blender/editors/space_text/space_text.cc
index 9d8c103b0f2..0a9535c3d38 100644
--- a/source/blender/editors/space_text/space_text.cc
+++ b/source/blender/editors/space_text/space_text.cc
@@ -376,19 +376,7 @@ static void text_properties_region_init(wmWindowManager *wm, ARegion *region)
 
 static void text_properties_region_draw(const bContext *C, ARegion *region)
 {
-  SpaceText *st = CTX_wm_space_text(C);
-
   ED_region_panels(C, region);
-
-  /* this flag trick is make sure buttons have been added already */
-  if (st->flags & ST_FIND_ACTIVATE) {
-    if (UI_textbutton_activate_rna(C, region, st, "find_text")) {
-      /* if the panel was already open we need to do another redraw */
-      ScrArea *area = CTX_wm_area(C);
-      WM_event_add_notifier(C, NC_SPACE | ND_SPACE_TEXT, area);
-    }
-    st->flags &= ~ST_FIND_ACTIVATE;
-  }
 }
 
 static void text_id_remap(ScrArea * /*area*/, SpaceLink *slink, const IDRemapper *mappings)
diff --git a/source/blender/editors/space_text/text_header.cc b/source/blender/editors/space_text/text_header.cc
index 60e09f9332f..36387346370 100644
--- a/source/blender/editors/space_text/text_header.cc
+++ b/source/blender/editors/space_text/text_header.cc
@@ -15,6 +15,8 @@
 #include "BKE_context.hh"
 #include "BKE_screen.hh"
 
+#include "DNA_text_types.h"
+
 #include "ED_screen.hh"
 
 #include "WM_types.hh"
@@ -67,15 +69,42 @@ static int text_text_search_exec(bContext *C, wmOperator * /*op*/)
   SpaceText *st = CTX_wm_space_text(C);
 
   if (region) {
-    if (region->flag & RGN_FLAG_HIDDEN) {
-      ED_region_toggle_hidden(C, region);
+    ARegion *active_region = CTX_wm_region(C);
+    Text *text = st->text;
+
+    /* Use active text selection as search query, if selection is on a single line. */
+    if (active_region->regiontype == RGN_TYPE_WINDOW && text && text->curl == text->sell &&
+        text->curc != text->selc)
+    {
+      const char *sel_start = text->curl->line +
+                              (text->curc < text->selc ? text->curc : text->selc);
+
+      const int sel_len = std::abs(text->curc - text->selc) + 1;
+      const int max_copy = sel_len < ST_MAX_FIND_STR ? sel_len : ST_MAX_FIND_STR;
+
+      BLI_strncpy(st->findstr, sel_start, max_copy);
     }
 
-    UI_panel_category_active_set(region, "Text");
+    bool draw = false;
 
-    /* cannot send a button activate yet for case when region wasn't visible yet */
-    /* flag gets checked and cleared in main draw callback */
-    st->flags |= ST_FIND_ACTIVATE;
+    if (region->flag & RGN_FLAG_HIDDEN) {
+      ED_region_toggle_hidden(C, region);
+      draw = true;
+    }
+
+    const char *active_category = UI_panel_category_active_get(region, false);
+    if (active_category && !STREQ(active_category, "Text")) {
+      UI_panel_category_active_set(region, "Text");
+      draw = true;
+    }
+
+    /* Build the layout and draw so `find_text` text button can be activated. */
+    if (draw) {
+      ED_region_do_layout(C, region);
+      ED_region_do_draw(C, region);
+    }
+
+    UI_textbutton_activate_rna(C, region, st, "find_text");
 
     ED_region_tag_redraw(region);
   }
diff --git a/source/blender/makesdna/DNA_space_types.h b/source/blender/makesdna/DNA_space_types.h
index 9eced9bae75..d920e91fd8e 100644
--- a/source/blender/makesdna/DNA_space_types.h
+++ b/source/blender/makesdna/DNA_space_types.h
@@ -1474,7 +1474,6 @@ typedef enum eSpaceText_Flags {
   ST_SHOW_MARGIN = (1 << 7),
   ST_MATCH_CASE = (1 << 8),
 
-  ST_FIND_ACTIVATE = (1 << 9),
 } eSpaceText_Flags;
 
 /* SpaceText.findstr/replacestr */