feat: persist window width across hide/restore

Save user-adjusted window width ratio when hiding and restore it
when restoring hidden windows.

Author: jensenojs

lua/opencode/state.lua

@@ -58,6 +58,7 @@
 ---@field api_client OpencodeApiClient
 ---@field event_manager EventManager|nil
 ---@field pre_zoom_width integer|nil
+---@field last_window_width_ratio number|nil
 ---@field required_version string
 ---@field opencode_cli_version string|nil
 ---@field current_cwd string|nil

lua/opencode/ui/input_window.lua

@@ -58,11 +58,7 @@ local function apply_dimensions(windows, height)
     return
   end
 
-  local total_width = vim.api.nvim_get_option_value('columns', {})
-  local width_ratio = state.pre_zoom_width and config.ui.zoom_width or config.ui.window_width
-  local width = math.floor(total_width * width_ratio)
-
-  pcall(vim.api.nvim_win_set_config, windows.input_win, { width = width, height = height })
+  pcall(vim.api.nvim_win_set_config, windows.input_win, { height = height })
 end
 
 function M.create_buf()

lua/opencode/ui/output_window.lua

@@ -133,7 +133,17 @@ function M.update_dimensions(windows)
     return
   end
   local total_width = vim.api.nvim_get_option_value('columns', {})
-  local width_ratio = state.pre_zoom_width and config.ui.zoom_width or config.ui.window_width
+
+  local width_ratio
+  if windows.saved_width_ratio then
+    width_ratio = windows.saved_width_ratio
+    windows.saved_width_ratio = nil
+  elseif state.pre_zoom_width then
+    width_ratio = config.ui.zoom_width
+  else
+    width_ratio = config.ui.window_width
+  end
+
   local width = math.floor(total_width * width_ratio)
 
   vim.api.nvim_win_set_config(windows.output_win, { width = width })

lua/opencode/ui/ui.lua

@@ -134,6 +134,14 @@ function M.hide_visible_windows(windows)
   end
 
   local snapshot = capture_hidden_snapshot(windows)
+
+  -- Only save width ratio for split modes (not dialog/current mode)
+  if config.ui.position ~= 'current' then
+    local total_cols = vim.o.columns
+    local current_width = vim.api.nvim_win_get_width(windows.output_win)
+    state.last_window_width_ratio = current_width / total_cols
+  end
+
   state.clear_hidden_window_state()
 
   prepare_window_close()
@@ -227,6 +235,7 @@ function M.restore_hidden_windows()
   windows.output_win = win_ids.output_win
   windows.footer_win = nil
   windows.output_was_at_bottom = hidden.output_was_at_bottom == true
+  windows.saved_width_ratio = state.last_window_width_ratio
 
   state.set_cursor_position('input', hidden.input_cursor)
   state.set_cursor_position('output', hidden.output_cursor)
@@ -349,6 +358,7 @@ function M.create_windows()
 
   windows.input_win = win_ids.input_win
   windows.output_win = win_ids.output_win
+  windows.saved_width_ratio = state.last_window_width_ratio
 
   input_window.setup(windows)
   output_window.setup(windows)

tests/unit/zoom_spec.lua

@@ -99,24 +99,23 @@ describe('ui zoom state', function()
   end)
 
   describe('input_window.update_dimensions', function()
-    it('uses default window_width when not zoomed', function()
+    it('does not change input window width', function()
+      local original_width = vim.api.nvim_win_get_width(windows.input_win)
+      
       input_window.update_dimensions(windows)
 
-      local expected_width = math.floor(config.ui.window_width * vim.o.columns)
       local actual_width = vim.api.nvim_win_get_width(windows.input_win)
-
-      assert.equals(expected_width, actual_width)
+      assert.equals(original_width, actual_width)
     end)
 
-    it('uses zoom_width when zoomed', function()
+    it('does not change input window width when zoomed', function()
       state.pre_zoom_width = 80
+      local original_width = vim.api.nvim_win_get_width(windows.input_win)
 
       input_window.update_dimensions(windows)
 
-      local expected_width = math.floor(config.ui.zoom_width * vim.o.columns)
       local actual_width = vim.api.nvim_win_get_width(windows.input_win)
-
-      assert.equals(expected_width, actual_width)
+      assert.equals(original_width, actual_width)
     end)
 
     it('preserves zoom state after update_dimensions', function()