Fix BeforeEdit cursor removal, add multicursor deletion

src/basic/basic.h

@@ -183,16 +183,47 @@ for (int i = 0; i < array.len; i += 1) {
     }
 }
 
+// Simple delete
+
 IterRemove(arr) {
     IterRemovePrepare(arr);
 
     remove_item = true;
 }
 
+//
+// Deleting backwards
+//
+
 For(arr.reverse_iter()) {
     defer{ arr.unordered_remove(it); };
 }
 
+//
+// When double looping and deleting
+//
+
+Array<Cursor *> deleted_cursors = {scratch};
+ForItem(cursor, window->cursors) {
+    For(deleted_cursors) if (it == &cursor) goto end_of_cursor_loop;
+
+    For(window->cursors) {
+        if (&it == &cursor) break;
+        bool a = cursor.range.max >= it.range.min && cursor.range.max <= it.range.max;
+        bool b = cursor.range.min >= it.range.min && cursor.range.min <= it.range.max;
+        if (a || b) {
+            deleted_cursors.add(&it);
+            cursor.range.max = Max(cursor.range.max, it.range.max);
+            cursor.range.min = Min(cursor.range.min, it.range.min);
+            break;
+        }
+    }
+end_of_cursor_loop:;
+}
+
+For(deleted_cursors) window->cursors.ordered_remove(*it);
+
+
 */
 #define IterRemove(a) for (int i = 0; i < (a).len; i += 1)
 #define IterRemovePrepare(a)        \

src/text_editor/layout.cpp

@@ -247,21 +247,29 @@ Array<LayoutColumn> CalculateVisibleColumns(Arena *arena, Window &window) {
 }
 
 void BeforeEdit(Window *window) {
+    Scratch scratch;
     // Merge cursors that overlap, this needs to be handled before any edits to
     // make sure overlapping edits won't happen.
-    for (int64_t cursor_i = 0; cursor_i < window->cursors.len; cursor_i += 1) {
-        Cursor &cursor = window->cursors[cursor_i];
-        IterRemove(window->cursors) {
-            IterRemovePrepare(window->cursors);
-            if (&cursor == &it) continue;
+    // @optimize: could probably reverse the inner loop and simply unordered remove
+    Array<Cursor *> deleted_cursors = {scratch};
+    ForItem(cursor, window->cursors) {
+        For(deleted_cursors) if (it == &cursor) goto end_of_cursor_loop;
 
-            if (cursor.range.max >= it.range.min && cursor.range.max <= it.range.max) {
-                remove_item      = true;
-                cursor.range.max = it.range.max;
+        For(window->cursors) {
+            if (&it == &cursor) break;
+            bool a = cursor.range.max >= it.range.min && cursor.range.max <= it.range.max;
+            bool b = cursor.range.min >= it.range.min && cursor.range.min <= it.range.max;
+            if (a || b) {
+                deleted_cursors.add(&it);
+                cursor.range.max = Max(cursor.range.max, it.range.max);
+                cursor.range.min = Min(cursor.range.min, it.range.min);
                 break;
             }
         }
+    end_of_cursor_loop:;
     }
+
+    For(deleted_cursors) window->cursors.ordered_remove(*it);
 }
 
 void AfterEdit(Window *window, Array<Edit> edits) {

src/text_editor/main.cpp

@@ -312,22 +312,51 @@ int main() {
             }
 
             if (IsKeyPressed(KEY_DELETE) || IsKeyPressedRepeat(KEY_DELETE)) {
-                if (IsKeyDown(KEY_LEFT_SHIFT)) {
-                }
-            }
-            if (IsKeyPressed(KEY_BACKSPACE) || IsKeyPressedRepeat(KEY_BACKSPACE)) {
-                if (IsKeyDown(KEY_LEFT_SHIFT)) {
-                } else {
-                    BeforeEdit(focused_window);
-                    Array<Edit> edits  = {FrameArena};
-                    String      string = {};
-                    For(focused_window->cursors) {
-                        int64_t pos = MoveLeft(focused_window->buffer, it.range.min);
-                        AddEdit(&edits, {pos, it.range.min}, string);
+                // Select things to delete
+                For(focused_window->cursors) {
+                    if (GetRangeSize(it.range)) continue;
+                    if (IsKeyDown(KEY_LEFT_CONTROL)) {
+                        int64_t pos = Seek(focused_window->buffer, it.range.min, ITERATE_FORWARD);
+                        it          = MakeCursor(it.range.min, pos);
+                    } else {
+                        int64_t pos = MoveRight(focused_window->buffer, it.range.min);
+                        it          = MakeCursor(it.range.min, pos);
                     }
-                    ApplyEdits(&focused_window->buffer, edits);
-                    AfterEdit(focused_window, edits);
                 }
+
+                // Merge
+                BeforeEdit(focused_window);
+
+                // Modify
+                Array<Edit> edits  = {FrameArena};
+                String      string = {};
+                For(focused_window->cursors) AddEdit(&edits, it.range, string);
+                ApplyEdits(&focused_window->buffer, edits);
+                AfterEdit(focused_window, edits);
+            }
+
+            if (IsKeyPressed(KEY_BACKSPACE) || IsKeyPressedRepeat(KEY_BACKSPACE)) {
+                // Select things to delete
+                For(focused_window->cursors) {
+                    if (GetRangeSize(it.range)) continue;
+                    if (IsKeyDown(KEY_LEFT_CONTROL)) {
+                        int64_t pos = Seek(focused_window->buffer, it.range.min, ITERATE_BACKWARD);
+                        it          = MakeCursor(pos, it.range.min);
+                    } else {
+                        int64_t pos = MoveLeft(focused_window->buffer, it.range.min);
+                        it          = MakeCursor(pos, it.range.min);
+                    }
+                }
+
+                // Merge
+                BeforeEdit(focused_window);
+
+                // Modify
+                Array<Edit> edits  = {FrameArena};
+                String      string = {};
+                For(focused_window->cursors) AddEdit(&edits, it.range, string);
+                ApplyEdits(&focused_window->buffer, edits);
+                AfterEdit(focused_window, edits);
             }
 
             if (IsKeyPressed(KEY_ENTER) || IsKeyPressedRepeat(KEY_ENTER)) {