From 9f468c44d9003e2e6d9fbf4628134291f5d6e069 Mon Sep 17 00:00:00 2001
From: Ryan Fleury <ryan.j.fleury@gmail.com>
Date: Wed, 30 Apr 2025 11:57:35 -0700
Subject: [PATCH] ditto

---
 src/raddbg/raddbg_core.c | 35 +++++++++++++++++++++--------------
 1 file changed, 21 insertions(+), 14 deletions(-)

diff --git a/src/raddbg/raddbg_core.c b/src/raddbg/raddbg_core.c
index bb183f49..5a1f24d2 100644
--- a/src/raddbg/raddbg_core.c
+++ b/src/raddbg/raddbg_core.c
@@ -4265,41 +4265,48 @@ rd_view_ui(Rng2F32 rect)
                 UI_Signal sig = ui_signal_from_box(drop_target);
                 if(ui_key_match(ui_drop_hot_key(), drop_target->key))
                 {
-                  Vec2F32 drop_pos = sub_2f32(ui_mouse(), rect.p0);
+                  Vec2F32 drag_pos = sub_2f32(ui_mouse(), rect.p0);
                   RD_RegSlot drag_slot = rd_state->drag_drop_regs_slot;
                   RD_Regs *drag_regs = rd_state->drag_drop_regs;
                   
                   //- rjf: obtain best fit for target block & prev-row for this drag
-                  EV_Block *watches_block = &ev_nil_block;
+                  EV_Block *drag_block = &ev_nil_block;
                   U64 best_prev_row_block_num = 0;
                   F32 best_prev_row_y = 0;
-                  F32 best_prev_row_distance = inf32();
                   {
+                    F32 best_prev_row_distance = inf32();
                     U64 local_row_idx = 0;
                     F32 row_y = 0;
                     for(EV_WindowedRowNode *row_node = rows.first; row_node != 0; row_node = row_node->next, local_row_idx += 1)
                     {
+                      // rjf: unpack row
                       EV_Row *row = &row_node->row;
                       F32 row_height = row_height_px*row->visual_size;
                       RD_WatchRowInfo *row_info = &row_infos[local_row_idx];
                       E_Type *block_type = e_type_from_key__cached(row->block->eval.irtree.type_key);
-                      if(drag_slot == RD_RegSlot_Expr &&
-                         block_type->expand.id_from_num == E_TYPE_EXPAND_ID_FROM_NUM_FUNCTION_NAME(watches) &&
-                         (drag_regs->cfg == 0 ||
-                          (drag_regs->cfg != row_info->group_cfg_child->id)))
+                      
+                      // rjf: determine if this row's block is good for the current drag/drop
+                      B32 block_is_good_for_drop = 0;
+                      if(drag_slot == RD_RegSlot_Expr && block_type->expand.id_from_num == E_TYPE_EXPAND_ID_FROM_NUM_FUNCTION_NAME(watches))
                       {
-                        if(watches_block == &ev_nil_block && row_y <= drop_pos.y && drop_pos.y <= row_y + row_height)
+                        block_is_good_for_drop = (drag_regs->cfg == 0 || (drag_regs->cfg != row_info->group_cfg_child->id));
+                      }
+                      
+                      // rjf: if this block is good, then test this row/block & grab if appropriate
+                      if(block_is_good_for_drop)
+                      {
+                        if(drag_block == &ev_nil_block && row_y <= drag_pos.y && drag_pos.y <= row_y + row_height)
                         {
-                          watches_block = row->block;
+                          drag_block = row->block;
                         }
-                        F32 row_distance = abs_f32(drop_pos.y - row_y);
+                        F32 row_distance = abs_f32(drag_pos.y - row_y);
                         if(row_distance <= best_prev_row_distance)
                         {
                           U64 row_num = ev_block_num_from_id(row->block, row->key.child_id);
                           best_prev_row_block_num = row_num-1;
                           best_prev_row_distance = row_distance;
                           best_prev_row_y = row_y;
-                          watches_block = row->block;
+                          drag_block = row->block;
                         }
                       }
                       row_y += row_height;
@@ -4310,13 +4317,13 @@ rd_view_ui(Rng2F32 rect)
                   B32 drag_target_is_good = 0;
                   RD_Cfg *drag_parent_cfg = &rd_nil_cfg;
                   RD_Cfg *drag_prev_cfg = &rd_nil_cfg;
-                  if(watches_block != &ev_nil_block)
+                  if(drag_block != &ev_nil_block)
                   {
-                    EV_Key prev_row_key = ev_key_make(ev_hash_from_key(watches_block->key), ev_block_id_from_num(watches_block, best_prev_row_block_num));
+                    EV_Key prev_row_key = ev_key_make(ev_hash_from_key(drag_block->key), ev_block_id_from_num(drag_block, best_prev_row_block_num));
                     U64 prev_row_num = ev_num_from_key(&block_ranges, prev_row_key);
                     EV_Row *prev_row = ev_row_from_num(scratch.arena, eval_view, filter, &block_ranges, prev_row_num);
                     RD_WatchRowInfo prev_row_info = rd_watch_row_info_from_row(scratch.arena, prev_row);
-                    drag_parent_cfg = rd_cfg_from_eval_space(watches_block->eval.space);
+                    drag_parent_cfg = rd_cfg_from_eval_space(drag_block->eval.space);
                     drag_prev_cfg = prev_row_info.group_cfg_child;
                     if(drag_regs->cfg == 0 || drag_prev_cfg->id != drag_regs->cfg)
                     {