From 3aa4806515bcf5040cbfe6b34e704ac6959e7b6e Mon Sep 17 00:00:00 2001
From: Krzosa Karol <krzosa.karol@gmail.com>
Date: Sat, 10 Aug 2024 07:25:44 +0200
Subject: [PATCH] Fix non-edit doing caret adjustment

---
 src/text_editor/buffer_history.cpp | 57 ++++++++++++++++++++----------
 1 file changed, 39 insertions(+), 18 deletions(-)

diff --git a/src/text_editor/buffer_history.cpp b/src/text_editor/buffer_history.cpp
index fe32d7d..fd450df 100644
--- a/src/text_editor/buffer_history.cpp
+++ b/src/text_editor/buffer_history.cpp
@@ -119,7 +119,7 @@ void AssertRanges(Array<Caret> carets) {
     }
 }
 
-void AdjustCarets(Array<Edit> edits, Array<Caret> *carets, bool kill_selection = false) {
+void AdjustCarets(Array<Edit> edits, Array<Caret> *carets) {
     Scratch      scratch;
     Array<Caret> new_carets = TightCopy(scratch, *carets);
     ForItem(edit, edits) {
@@ -131,28 +131,14 @@ void AdjustCarets(Array<Edit> edits, Array<Caret> *carets, bool kill_selection =
             Caret &old_cursor = carets->data[i];
             Caret &new_cursor = new_carets.data[i];
 
-            if (old_cursor.range.min == edit.range.min) {
-                new_cursor.range.min += insert_size;
-            } else if (old_cursor.range.min > edit.range.min) {
+            if (old_cursor.range.min > edit.range.min) {
                 new_cursor.range.min += offset;
-            }
-
-            if (old_cursor.range.max == edit.range.max) {
-                new_cursor.range.max += insert_size;
-            } else if (old_cursor.range.max > edit.range.max) {
                 new_cursor.range.max += offset;
             }
         }
     }
 
-    for (Int i = 0; i < carets->len; i += 1) {
-        carets->data[i] = new_carets[i];
-        if (kill_selection) {
-            carets->data[i].range.max = carets->data[i].range.min;
-        }
-    }
-
-    IF_DEBUG(AssertRanges(*carets));
+    for (Int i = 0; i < carets->len; i += 1) carets->data[i] = new_carets[i];
 }
 
 bool KILL_SELECTION = true;
@@ -174,5 +160,40 @@ void EndEdit(Buffer *buffer, Array<Edit> *edits, Array<Caret> *carets, bool kill
     }
 #endif
 
-    AdjustCarets(*edits, carets, kill_selection);
+    // Adjust carets
+    // this one also moves the carets forward if they are aligned with edit
+    //
+    Scratch      scratch;
+    Array<Caret> new_carets = TightCopy(scratch, *carets);
+    ForItem(edit, *edits) {
+        Int remove_size = GetSize(edit.range);
+        Int insert_size = edit.string.len;
+        Int offset      = insert_size - remove_size;
+
+        for (Int i = 0; i < carets->len; i += 1) {
+            Caret &old_cursor = carets->data[i];
+            Caret &new_cursor = new_carets.data[i];
+
+            if (old_cursor.range.min == edit.range.min) {
+                new_cursor.range.min += insert_size;
+            } else if (old_cursor.range.min > edit.range.min) {
+                new_cursor.range.min += offset;
+            }
+
+            if (old_cursor.range.max == edit.range.max) {
+                new_cursor.range.max += insert_size;
+            } else if (old_cursor.range.max > edit.range.max) {
+                new_cursor.range.max += offset;
+            }
+
+            Assert(new_cursor.range.max >= new_cursor.range.min);
+        }
+    }
+
+    for (Int i = 0; i < carets->len; i += 1) {
+        carets->data[i] = new_carets[i];
+        if (kill_selection) {
+            carets->data[i].range.max = carets->data[i].range.min;
+        }
+    }
 }