fix(ui): prevent duplicate windows

lua/opencode/ui/autocmds.lua

@@ -75,15 +75,18 @@ function M.setup_autocmds(windows)
   end
 end
 
+---@param windows OpencodeWindowState?
 function M.setup_resize_handler(windows)
   local resize_group = vim.api.nvim_create_augroup('OpencodeResize', { clear = true })
   vim.api.nvim_create_autocmd('VimResized', {
     group = resize_group,
     callback = function()
+      require('opencode.ui.ui').reconcile_windows(windows, 'input')
+      require('opencode.ui.ui').reconcile_windows(windows, 'output')
       require('opencode.ui.topbar').render()
       require('opencode.ui.footer').update_window(windows)
-      require('opencode.ui.input_window').update_dimensions(windows)
-      require('opencode.ui.output_window').update_dimensions(windows)
+      input_window.update_dimensions(windows)
+      output_window.update_dimensions(windows)
     end,
   })
 

lua/opencode/ui/output_window.lua

@@ -23,6 +23,7 @@ function M._build_output_win_config()
   }
 end
 
+---@param windows OpencodeWindowState?
 function M.mounted(windows)
   windows = windows or state.windows
   return windows and windows.output_buf and windows.output_win and vim.api.nvim_win_is_valid(windows.output_win)

lua/opencode/ui/ui.lua

@@ -296,4 +296,48 @@ function M.toggle_zoom()
   end
 end
 
+---Reconcile window state when duplicate windows may have been created
+---This can happen when external commands like 'tabdo' manipulate window layouts
+---@param windows OpencodeWindowState?
+---@param key string
+function M.reconcile_windows(windows, key)
+  local buf_key = key .. '_buf'
+  if not windows or not windows[buf_key] then
+    return
+  end
+
+  local wins = vim.fn.win_findbuf(windows[buf_key])
+  if type(wins) ~= 'table' or #wins == 0 then
+    return
+  end
+
+  local valid_wins = {}
+  for _, win in ipairs(wins) do
+    if vim.api.nvim_win_is_valid(win) then
+      table.insert(valid_wins, win)
+    end
+  end
+  if #valid_wins == 0 then
+    return
+  end
+
+  local current_tab = vim.api.nvim_get_current_tabpage()
+  local preferred = nil
+  for _, win in ipairs(valid_wins) do
+    if vim.api.nvim_win_get_tabpage(win) == current_tab then
+      preferred = win
+      break
+    end
+  end
+  preferred = preferred or valid_wins[1]
+
+  windows[key .. '_win'] = preferred
+
+  for _, win in ipairs(valid_wins) do
+    if win ~= preferred and vim.api.nvim_win_get_tabpage(win) == current_tab then
+      pcall(vim.api.nvim_win_close, win, false)
+    end
+  end
+end
+
 return M