perf(ui): improve rendering performance and robustness

Author: sudo-tee

lua/opencode/ui/output_window.lua

@@ -30,7 +30,7 @@ function M.end_update()
   end
   _update_depth = _update_depth - 1
   if _update_depth == 0 and _update_buf then
-    vim.api.nvim_set_option_value('modifiable', false, { buf = _update_buf })
+    pcall(vim.api.nvim_set_option_value, 'modifiable', false, { buf = _update_buf })
     _update_buf = nil
   end
 end

lua/opencode/ui/render_state.lua

@@ -517,6 +517,26 @@ local function shift_action(action, delta)
   end
 end
 
+--- Binary-search sorted ranges for the first entry whose line_start >= from_line.
+--- Returns the index, or #ranges + 1 if none qualify.
+---@param ranges {[1]: integer, [2]: integer, [3]: string}[]
+---@param from_line integer
+---@return integer
+local function first_range_at_or_after(ranges, from_line)
+  local lo, hi = 1, #ranges
+  local result = #ranges + 1
+  while lo <= hi do
+    local mid = math.floor((lo + hi) / 2)
+    if ranges[mid][1] >= from_line then
+      result = mid
+      hi = mid - 1
+    else
+      lo = mid + 1
+    end
+  end
+  return result
+end
+
 function RenderState:shift_all(from_line, delta)
   if delta == 0 then
     return
@@ -526,18 +546,28 @@ function RenderState:shift_all(from_line, delta)
     return
   end
 
+  -- Build fresh sorted ranges so we can search for the first entry at
+  -- or after from_line, then iterate only the suffix that needs shifting.
+  self:_rebuild_ranges()
+
   local shifted = false
 
-  for _, msg_data in pairs(self._messages) do
-    if msg_data.line_start and msg_data.line_start >= from_line then
+  local msg_ranges = self._message_ranges
+  local first_msg = first_range_at_or_after(msg_ranges, from_line)
+  for i = first_msg, #msg_ranges do
+    local msg_data = self._messages[msg_ranges[i][3]]
+    if msg_data then
       msg_data.line_start = msg_data.line_start + delta
       msg_data.line_end = msg_data.line_end + delta
       shifted = true
     end
   end
 
-  for _, part_data in pairs(self._parts) do
-    if part_data.line_start and part_data.line_start >= from_line then
+  local part_ranges = self._part_ranges
+  local first_part = first_range_at_or_after(part_ranges, from_line)
+  for i = first_part, #part_ranges do
+    local part_data = self._parts[part_ranges[i][3]]
+    if part_data then
       part_data.line_start = part_data.line_start + delta
       part_data.line_end = part_data.line_end + delta
       shifted = true

lua/opencode/ui/renderer/buffer.lua

@@ -145,12 +145,11 @@ function M.write_formatted_data(formatted_data, part_id, start_line)
   if is_insertion then
     output_window.set_lines(new_lines, target_line, target_line)
   else
-    -- Append: temporarily add a separating blank line in-place to avoid an
-    -- O(n) copy, then restore. set_lines is synchronous so this is safe.
+    -- Append: overlap the last buffer line  with our lines
     target_line = target_line - 1
-    new_lines[#new_lines + 1] = ''
-    output_window.set_lines(new_lines, target_line)
-    new_lines[#new_lines] = nil
+    local append_lines = table.move(new_lines, 1, #new_lines, 1, {})
+    append_lines[#append_lines + 1] = ''
+    output_window.set_lines(append_lines, target_line)
   end
 
   if part_id and formatted_data.actions then
@@ -300,8 +299,8 @@ function M.remove_part(part_id)
     return
   end
   output_window.begin_update()
-  output_window.clear_extmarks(cached.line_start - 1, cached.line_end)
-  output_window.set_lines({}, cached.line_start - 1, cached.line_end)
+  output_window.clear_extmarks(cached.line_start - 1, cached.line_end + 1)
+  output_window.set_lines({}, cached.line_start, cached.line_end + 1)
   output_window.end_update()
   ctx.render_state:remove_part(part_id)
 end
@@ -362,8 +361,8 @@ function M.remove_message(message_id)
     return
   end
   output_window.begin_update()
-  output_window.clear_extmarks(cached.line_start - 1, cached.line_end)
-  output_window.set_lines({}, cached.line_start - 1, cached.line_end)
+  output_window.clear_extmarks(cached.line_start - 1, cached.line_end + 1)
+  output_window.set_lines({}, cached.line_start, cached.line_end + 1)
   output_window.end_update()
   ctx.render_state:remove_message(message_id)
 end

lua/opencode/ui/renderer/events.lua

@@ -410,7 +410,6 @@ function M.on_permission_updated(permission)
 
   permission_window.add_permission(permission)
   M.render_permissions_display()
-  buf.rerender_part('permission-display-part')
   scroll(true)
 end
 
@@ -432,9 +431,9 @@ function M.on_permission_replied(properties)
   if #state.pending_permissions == 0 then
     buf.remove_part('permission-display-part')
     buf.remove_message('permission-display-message')
+  else
+    M.render_permissions_display()
   end
-
-  buf.rerender_part('permission-display-part')
 end
 
 ---Handle question.asked — show the question picker UI