From ab440a50936c86ec9fca0339dff4eddda13bd371 Mon Sep 17 00:00:00 2001
From: Francis Belanger <francis.belanger@gmail.com>
Date: Wed, 18 Mar 2026 09:10:29 -0400
Subject: [PATCH 1/8] refactor(state): unify model clearing and improve
 renderer/session reset

---
 lua/opencode/core.lua           |  4 +---
 lua/opencode/state/model.lua    | 27 +++++++++++++++++++++++----
 lua/opencode/state/renderer.lua | 17 +++++++++++++++++
 lua/opencode/state/session.lua  |  4 +++-
 lua/opencode/ui/renderer.lua    | 17 ++++++++---------
 5 files changed, 52 insertions(+), 17 deletions(-)

diff --git a/lua/opencode/core.lua b/lua/opencode/core.lua
index f679aca6..86a68bb0 100644
--- a/lua/opencode/core.lua
+++ b/lua/opencode/core.lua
@@ -37,12 +37,10 @@ end)
 M.switch_session = Promise.async(function(session_id)
   local selected_session = session.get_by_id(session_id):await()
 
-  state.model.clear_model()
-  state.model.clear_mode()
+  state.model.clear()
   M.ensure_current_mode():await()
 
   state.session.set_active(selected_session)
-  state.session.reset_restore_points()
   if state.ui.is_visible() then
     ui.focus_input()
   else
diff --git a/lua/opencode/state/model.lua b/lua/opencode/state/model.lua
index 52ca63f4..e044a122 100644
--- a/lua/opencode/state/model.lua
+++ b/lua/opencode/state/model.lua
@@ -1,5 +1,17 @@
 local store = require('opencode.state.store')
 
+---@class OpencodeModelStateMutations
+---@field set_mode fun(mode: string|nil)
+---@field clear_mode fun()
+---@field set_model fun(model: string|nil)
+---@field clear_model fun()
+---@field clear fun()
+---@field set_model_info fun(info: table|nil)
+---@field set_variant fun(variant: string|nil)
+---@field clear_variant fun()
+---@field set_mode_model_map fun(mode_map: table<string, string>)
+---@field set_mode_model_override fun(mode: string, model: string)
+
 local M = {}
 
 ---@param mode string|nil
@@ -20,6 +32,12 @@ function M.clear_model()
   return store.set('current_model', nil)
 end
 
+function M.clear()
+  store.set('current_model', nil)
+  store.set('current_mode', nil)
+  store.set('current_variant', nil)
+end
+
 ---@param info table|nil
 function M.set_model_info(info)
   return store.set('current_model_info', info)
@@ -42,10 +60,11 @@ end
 ---@param mode string
 ---@param model string
 function M.set_mode_model_override(mode, model)
-  local state = store.state()
-  local mode_map = vim.deepcopy(state.user_mode_model_map)
-  mode_map[mode] = model
-  return store.set('user_mode_model_map', mode_map)
+  return store.update('user_mode_model_map', function(current)
+    local updated = vim.deepcopy(current)
+    updated[mode] = model
+    return updated
+  end)
 end
 
 return M
diff --git a/lua/opencode/state/renderer.lua b/lua/opencode/state/renderer.lua
index 002bbff1..ccc54763 100644
--- a/lua/opencode/state/renderer.lua
+++ b/lua/opencode/state/renderer.lua
@@ -8,6 +8,8 @@ local store = require('opencode.state.store')
 ---@field set_pending_permissions fun(permissions: OpencodePermission[])
 ---@field set_cost fun(cost: number)
 ---@field set_tokens_count fun(count: number)
+---@field set_stats fun(tokens_count: number, cost: number)
+---@field reset fun()
 
 local M = {}
 
@@ -41,4 +43,19 @@ function M.set_tokens_count(count)
   return store.set('tokens_count', count)
 end
 
+---@param tokens_count number
+---@param cost number
+function M.set_stats(tokens_count, cost)
+  store.set('tokens_count', tokens_count)
+  store.set('cost', cost)
+end
+
+function M.reset()
+  store.set('messages', {})
+  store.set('last_user_message', nil)
+  store.set('tokens_count', 0)
+  store.set('cost', 0)
+  store.set('pending_permissions', {})
+end
+
 return M
diff --git a/lua/opencode/state/session.lua b/lua/opencode/state/session.lua
index 078f4527..afc18662 100644
--- a/lua/opencode/state/session.lua
+++ b/lua/opencode/state/session.lua
@@ -12,7 +12,9 @@ local M = {}
 
 ---@param session Session|nil
 function M.set_active(session)
-  M.clear_active()
+  store.set('restore_points', {})
+  store.set('last_sent_context', nil)
+  store.set('user_message_count', {})
   return store.set('active_session', session)
 end
 
diff --git a/lua/opencode/ui/renderer.lua b/lua/opencode/ui/renderer.lua
index 20d2d86e..850d2a60 100644
--- a/lua/opencode/ui/renderer.lua
+++ b/lua/opencode/ui/renderer.lua
@@ -43,10 +43,6 @@ function M.reset()
 
   output_window.clear()
 
-  state.renderer.set_messages({})
-  state.renderer.set_last_user_message(nil)
-  state.renderer.set_tokens_count(0)
-
   local permissions = state.pending_permissions or {}
   if #permissions > 0 and state.api_client then
     for _, permission in ipairs(permissions) do
@@ -54,7 +50,7 @@ function M.reset()
     end
   end
   permission_window.clear_all()
-  state.renderer.set_pending_permissions({})
+  state.renderer.reset()
 
   trigger_on_data_rendered()
 end
@@ -1198,11 +1194,14 @@ function M._update_stats_from_message(message)
   end
 
   local tokens = message.info.tokens
-  if tokens and tokens.input > 0 then
+  if tokens and tokens.input > 0 and message.info.cost and type(message.info.cost) == 'number' then
+    state.renderer.set_stats(
+      tokens.input + tokens.output + tokens.cache.read + tokens.cache.write,
+      message.info.cost
+    )
+  elseif tokens and tokens.input > 0 then
     state.renderer.set_tokens_count(tokens.input + tokens.output + tokens.cache.read + tokens.cache.write)
-  end
-
-  if message.info.cost and type(message.info.cost) == 'number' then
+  elseif message.info.cost and type(message.info.cost) == 'number' then
     state.renderer.set_cost(message.info.cost)
   end
 end

From 5429155c5735e01a5bf6aa3df390ece3e211d737 Mon Sep 17 00:00:00 2001
From: Francis Belanger <francis.belanger@gmail.com>
Date: Wed, 18 Mar 2026 12:54:42 -0400
Subject: [PATCH 2/8] feat(store): add batched state updates and mutate API

---
 lua/opencode/context.lua        |  17 ++---
 lua/opencode/core.lua           |   3 +-
 lua/opencode/server_job.lua     |   1 +
 lua/opencode/state.lua          |   2 +-
 lua/opencode/state/context.lua  |   9 ++-
 lua/opencode/state/init.lua     |   1 +
 lua/opencode/state/jobs.lua     |  10 ---
 lua/opencode/state/model.lua    |  19 ++----
 lua/opencode/state/renderer.lua |  33 +++++-----
 lua/opencode/state/session.lua  |  27 ++++----
 lua/opencode/state/store.lua    | 113 ++++++++++++++++++++++++++------
 lua/opencode/state/ui.lua       |  45 +++++++------
 lua/opencode/ui/autocmds.lua    |   3 +-
 lua/opencode/ui/renderer.lua    |  22 +++----
 lua/opencode/ui/ui.lua          |  30 ++++-----
 tests/unit/state_spec.lua       |  61 +++++++++++++++++
 16 files changed, 248 insertions(+), 148 deletions(-)

diff --git a/lua/opencode/context.lua b/lua/opencode/context.lua
index 52cfe236..e3e93d61 100644
--- a/lua/opencode/context.lua
+++ b/lua/opencode/context.lua
@@ -22,14 +22,10 @@ local toggleable_context_keys = {
 ---@param context_key OpencodeToggleableContextKey
 ---@return table
 local function ensure_context_state(context_key)
-  local current_config = state.current_context_config or {}
-  local current = current_config[context_key]
-  local new_config = vim.deepcopy(current_config)
   local defaults = vim.tbl_get(config, 'context', context_key) or {}
-
-  new_config[context_key] = vim.tbl_deep_extend('force', {}, defaults, current or {})
-  state.context.set_current_context_config(new_config)
-  return new_config[context_key]
+  return state.context.update_current_context_config(function(current_config)
+    current_config[context_key] = vim.tbl_deep_extend('force', {}, defaults, current_config[context_key] or {})
+  end)[context_key]
 end
 
 M.ChatContext = ChatContext
@@ -200,12 +196,7 @@ function M.build_inline_selection_text(range)
   end
 
   local filetype = vim.bo[buf].filetype or ''
-  local text = string.format(
-    '**`%s`**\n\n```%s\n%s\n```',
-    file.path,
-    filetype,
-    current_selection.text
-  )
+  local text = string.format('**`%s`**\n\n```%s\n%s\n```', file.path, filetype, current_selection.text)
 
   return text
 end
diff --git a/lua/opencode/core.lua b/lua/opencode/core.lua
index 86a68bb0..7ceb3a3f 100644
--- a/lua/opencode/core.lua
+++ b/lua/opencode/core.lua
@@ -92,8 +92,7 @@ M.open = Promise.async(function(opts)
 
   if are_windows_closed then
     if not ui.is_opencode_focused() then
-      state.ui.set_last_code_window(vim.api.nvim_get_current_win())
-      state.ui.set_current_code_buf(vim.api.nvim_get_current_buf())
+      state.ui.set_code_context(vim.api.nvim_get_current_win(), vim.api.nvim_get_current_buf())
     end
 
     M.is_prompting_allowed()
diff --git a/lua/opencode/server_job.lua b/lua/opencode/server_job.lua
index d689b62d..f3b04817 100644
--- a/lua/opencode/server_job.lua
+++ b/lua/opencode/server_job.lua
@@ -293,6 +293,7 @@ function M.spawn_local_server(promise, port, hostname)
       log.notify(string.format('Started local server at %s', base_url), vim.log.levels.INFO)
       if url_port then
         local port_num = tonumber(url_port)
+        state.store.set_raw('opencode_server', state.opencode_server)
         state.opencode_server.port = port_num
         local server_pid = job and job.pid
         port_mapping.register(port_num, vim.fn.getcwd(), true, 'serve', nil, server_pid)
diff --git a/lua/opencode/state.lua b/lua/opencode/state.lua
index 1012b254..3a61de36 100644
--- a/lua/opencode/state.lua
+++ b/lua/opencode/state.lua
@@ -1 +1 @@
-return require('opencode.state.init') --[[@as OpencodeStateModule]]
+return require('opencode.state.init') --[[@as OpencodeState]]
diff --git a/lua/opencode/state/context.lua b/lua/opencode/state/context.lua
index 692bbc4e..b12a8602 100644
--- a/lua/opencode/state/context.lua
+++ b/lua/opencode/state/context.lua
@@ -1,11 +1,6 @@
-
 local store = require('opencode.state.store')
 
 ---@class OpencodeContextStateMutations
----@field set_current_context_config fun(config: OpencodeContextConfig|nil)
----@field set_context_updated_at fun(timestamp: number|nil)
----@field set_current_cwd fun(cwd: string|nil)
-
 local M = {}
 
 ---@param config OpencodeContextConfig|nil
@@ -13,6 +8,10 @@ function M.set_current_context_config(config)
   return store.set('current_context_config', config)
 end
 
+function M.update_current_context_config(mutator)
+  return store.mutate('current_context_config', mutator)
+end
+
 ---@param timestamp number|nil
 function M.set_context_updated_at(timestamp)
   return store.set('context_updated_at', timestamp)
diff --git a/lua/opencode/state/init.lua b/lua/opencode/state/init.lua
index 408f12b6..f7a0f318 100644
--- a/lua/opencode/state/init.lua
+++ b/lua/opencode/state/init.lua
@@ -16,6 +16,7 @@ local context = require('opencode.state.context')
 ---@field context OpencodeContextStateMutations
 
 ---@alias OpencodeState OpencodeStateModule & OpencodeStateData
+
 ---@type OpencodeState
 local M = {
   store = store,
diff --git a/lua/opencode/state/jobs.lua b/lua/opencode/state/jobs.lua
index 42938c9f..288c521f 100644
--- a/lua/opencode/state/jobs.lua
+++ b/lua/opencode/state/jobs.lua
@@ -1,16 +1,6 @@
 local store = require('opencode.state.store')
 
 ---@class OpencodeJobStateMutations
----@field increment_count fun(delta?: integer)
----@field decrement_count fun(delta?: integer)
----@field set_count fun(count: integer)
----@field set_server fun(server: OpencodeServer|nil)
----@field clear_server fun()
----@field set_api_client fun(client: OpencodeApiClient|nil)
----@field set_event_manager fun(manager: EventManager|nil)
----@field set_opencode_cli_version fun(version: string|nil)
----@field is_running fun():boolean
-
 local M = {}
 
 ---@param delta integer|nil
diff --git a/lua/opencode/state/model.lua b/lua/opencode/state/model.lua
index e044a122..ae6396dd 100644
--- a/lua/opencode/state/model.lua
+++ b/lua/opencode/state/model.lua
@@ -1,17 +1,6 @@
 local store = require('opencode.state.store')
 
 ---@class OpencodeModelStateMutations
----@field set_mode fun(mode: string|nil)
----@field clear_mode fun()
----@field set_model fun(model: string|nil)
----@field clear_model fun()
----@field clear fun()
----@field set_model_info fun(info: table|nil)
----@field set_variant fun(variant: string|nil)
----@field clear_variant fun()
----@field set_mode_model_map fun(mode_map: table<string, string>)
----@field set_mode_model_override fun(mode: string, model: string)
-
 local M = {}
 
 ---@param mode string|nil
@@ -33,9 +22,11 @@ function M.clear_model()
 end
 
 function M.clear()
-  store.set('current_model', nil)
-  store.set('current_mode', nil)
-  store.set('current_variant', nil)
+  return store.batch(function()
+    store.set('current_model', nil)
+    store.set('current_mode', nil)
+    store.set('current_variant', nil)
+  end)
 end
 
 ---@param info table|nil
diff --git a/lua/opencode/state/renderer.lua b/lua/opencode/state/renderer.lua
index ccc54763..ab4c108f 100644
--- a/lua/opencode/state/renderer.lua
+++ b/lua/opencode/state/renderer.lua
@@ -1,16 +1,6 @@
-
 local store = require('opencode.state.store')
 
 ---@class OpencodeRendererStateMutations
----@field set_messages fun(messages: OpencodeMessage[]|nil)
----@field set_current_message fun(message: OpencodeMessage|nil)
----@field set_last_user_message fun(message: OpencodeMessage|nil)
----@field set_pending_permissions fun(permissions: OpencodePermission[])
----@field set_cost fun(cost: number)
----@field set_tokens_count fun(count: number)
----@field set_stats fun(tokens_count: number, cost: number)
----@field reset fun()
-
 local M = {}
 
 ---@param messages OpencodeMessage[]|nil
@@ -33,6 +23,10 @@ function M.set_pending_permissions(permissions)
   return store.set('pending_permissions', permissions)
 end
 
+---@param mutator fun(current_permissions: OpencodePermission[]): OpencodePermission[]
+function M.update_pending_permissions(mutator)
+  return store.mutate('pending_permissions', mutator)
+end
 ---@param cost number
 function M.set_cost(cost)
   return store.set('cost', cost)
@@ -46,16 +40,21 @@ end
 ---@param tokens_count number
 ---@param cost number
 function M.set_stats(tokens_count, cost)
-  store.set('tokens_count', tokens_count)
-  store.set('cost', cost)
+  return store.batch(function()
+    store.set('tokens_count', tokens_count)
+    store.set('cost', cost)
+  end)
 end
 
 function M.reset()
-  store.set('messages', {})
-  store.set('last_user_message', nil)
-  store.set('tokens_count', 0)
-  store.set('cost', 0)
-  store.set('pending_permissions', {})
+  return store.batch(function()
+    store.set('messages', {})
+    store.set('current_message', nil)
+    store.set('last_user_message', nil)
+    store.set('tokens_count', 0)
+    store.set('cost', 0)
+    store.set('pending_permissions', {})
+  end)
 end
 
 return M
diff --git a/lua/opencode/state/session.lua b/lua/opencode/state/session.lua
index afc18662..76ca483e 100644
--- a/lua/opencode/state/session.lua
+++ b/lua/opencode/state/session.lua
@@ -1,28 +1,25 @@
 local store = require('opencode.state.store')
 
 ---@class OpencodeSessionStateMutations
----@field set_active fun(session: Session|nil)
----@field clear_active fun()
----@field set_restore_points fun(points: RestorePoint[])
----@field reset_restore_points fun()
----@field set_last_sent_context fun(context: OpencodeContext|nil)
----@field set_user_message_count fun(count: table<string, number>)
-
 local M = {}
 
 ---@param session Session|nil
 function M.set_active(session)
-  store.set('restore_points', {})
-  store.set('last_sent_context', nil)
-  store.set('user_message_count', {})
-  return store.set('active_session', session)
+  return store.batch(function()
+    store.set('restore_points', {})
+    store.set('last_sent_context', nil)
+    store.set('user_message_count', {})
+    return store.set('active_session', session)
+  end)
 end
 
 function M.clear_active()
-  M.reset_restore_points()
-  M.set_last_sent_context()
-  M.set_user_message_count({})
-  return store.set('active_session', nil)
+  return store.batch(function()
+    store.set('restore_points', {})
+    store.set('last_sent_context', nil)
+    store.set('user_message_count', {})
+    return store.set('active_session', nil)
+  end)
 end
 
 ---@param points RestorePoint[]
diff --git a/lua/opencode/state/store.lua b/lua/opencode/state/store.lua
index 96e83dd4..b2e3f63f 100644
--- a/lua/opencode/state/store.lua
+++ b/lua/opencode/state/store.lua
@@ -87,6 +87,54 @@ local _state = {
 }
 
 local _listeners = {}
+local _batch_depth = 0
+local _batched_changes = {}
+local _batched_order = {}
+
+---@generic K extends keyof OpencodeStateData
+---@param key K
+---@param new_val std.RawGet<OpencodeStateData, K>
+---@param old_val std.RawGet<OpencodeStateData, K>
+local function queue_emit(key, new_val, old_val)
+  if vim.deep_equal(old_val, new_val) then
+    return false
+  end
+
+  if _batch_depth == 0 then
+    M.emit(key, new_val, old_val)
+    return true
+  end
+
+  if not _batched_changes[key] then
+    _batched_changes[key] = {
+      old_val = old_val,
+      new_val = new_val,
+    }
+    table.insert(_batched_order, key)
+    return true
+  end
+
+  _batched_changes[key].new_val = new_val
+  return true
+end
+
+local function flush_batched_emits()
+  if _batch_depth > 0 or #_batched_order == 0 then
+    return
+  end
+
+  local pending_changes = _batched_changes
+  local pending_order = _batched_order
+  _batched_changes = {}
+  _batched_order = {}
+
+  for _, key in ipairs(pending_order) do
+    local change = pending_changes[key]
+    if change then
+      M.emit(key, change.new_val, change.old_val)
+    end
+  end
+end
 
 function M.state()
   return _state
@@ -107,9 +155,7 @@ function M.set(key, value)
   local old = _state[key]
 
   _state[key] = value
-  if not vim.deep_equal(old, value) then
-    M.emit(key, value, old)
-  end
+  queue_emit(key, value, old)
 
   return value
 end
@@ -119,7 +165,8 @@ end
 ---@param value std.RawGet<OpencodeStateData, K>
 ---@return std.RawGet<OpencodeStateData, K>
 function M.set_raw(key, value)
-  return M.set(key, value)
+  _state[key] = value
+  return value
 end
 
 ---@generic K extends keyof OpencodeStateData
@@ -132,6 +179,43 @@ function M.update(key, updater)
   return next_value
 end
 
+---@param callback fun(store: OpencodeStateStore)
+function M.batch(callback)
+  _batch_depth = _batch_depth + 1
+  local ok, result = pcall(callback, M)
+  _batch_depth = _batch_depth - 1
+
+  if _batch_depth == 0 then
+    flush_batched_emits()
+  end
+
+  if not ok then
+    error(result, 0)
+  end
+
+  return result
+end
+
+---@generic K extends keyof OpencodeStateData
+---@param key K
+---@param mutator fun(current: std.RawGet<OpencodeStateData, K>):nil
+---@return std.RawGet<OpencodeStateData, K>
+function M.mutate(key, mutator)
+  if _state[key] == nil then
+    _state[key] = {} --[[@as std.RawGet<OpencodeStateData, K>]]
+  end
+
+  if type(_state[key]) ~= 'table' then
+    error('State key is not a table: ' .. key)
+  end
+
+  local current = _state[key]
+  local old = vim.tbl_extend('force', {}, current)
+  mutator(current)
+  queue_emit(key, current, old)
+  return current
+end
+
 ---@generic K extends keyof OpencodeStateData
 ---@param key K|K[]|nil
 ---@param cb fun(key:K, new_val:std.RawGet<OpencodeStateData, K>, old_val:std.RawGet<OpencodeStateData, K>)
@@ -204,16 +288,10 @@ function M.append(key, value)
   if type(value) ~= 'table' then
     error('Value must be a table to append')
   end
-  if not _state[key] then
-    _state[key] = {}
-  end
-  if type(_state[key]) ~= 'table' then
-    error('State key is not a table: ' .. key)
-  end
 
-  local old = vim.deepcopy(_state[key] --[[@as table]])
-  table.insert(_state[key] --[[@as table]], value)
-  M.emit(key, _state[key], old)
+  M.mutate(key, function(current)
+    table.insert(current --[[@as table]], value)
+  end)
 end
 
 ---@generic K extends keyof OpencodeStateData
@@ -223,13 +301,10 @@ function M.remove(key, idx)
   if not _state[key] then
     return
   end
-  if type(_state[key]) ~= 'table' then
-    error('State key is not a table: ' .. key)
-  end
 
-  local old = vim.deepcopy(_state[key] --[[@as table]])
-  table.remove(_state[key] --[[@as table]], idx)
-  M.emit(key, _state[key], old)
+  M.mutate(key, function(current)
+    table.remove(current --[[@as table]], idx)
+  end)
 end
 
 return M
diff --git a/lua/opencode/state/ui.lua b/lua/opencode/state/ui.lua
index ac84e1ee..cadc627e 100644
--- a/lua/opencode/state/ui.lua
+++ b/lua/opencode/state/ui.lua
@@ -26,21 +26,6 @@ local store = require('opencode.state.store')
 ---@field output_was_at_bottom boolean|nil
 
 ---@class OpencodeUiStateMutations
----@field set_windows fun(windows: OpencodeWindowState|nil)
----@field clear_windows fun()
----@field set_opening fun(is_opening: boolean)
----@field set_panel_focused fun(is_focused: boolean)
----@field set_last_focused_window fun(win_type: 'input'|'output'|nil)
----@field set_display_route fun(route: any)
----@field clear_display_route fun()
----@field set_last_code_window fun(win_id: integer|nil)
----@field set_current_code_buf fun(bufnr: integer|nil)
----@field set_last_window_width_ratio fun(ratio: number|nil)
----@field clear_last_window_width_ratio fun()
----@field set_input_content fun(lines: table|nil)
----@field set_saved_window_options fun(opts: table|nil)
----@field set_pre_zoom_width fun(width: integer|nil)
-
 local M = {}
 
 local _state = store.state()
@@ -88,6 +73,26 @@ function M.set_current_code_buf(bufnr)
   return store.set('current_code_buf', bufnr)
 end
 
+---@param win_id integer|nil
+---@param bufnr integer|nil
+function M.set_code_context(win_id, bufnr)
+  store.batch(function()
+    store.set('last_code_win_before_opencode', win_id)
+    store.set('current_code_buf', bufnr)
+  end)
+end
+
+---Clear window IDs while keeping buffer references, used when hiding windows
+---@param output_was_at_bottom boolean
+function M.mark_windows_hidden(output_was_at_bottom)
+  store.mutate('windows', function(win)
+    win.input_win = nil
+    win.output_win = nil
+    win.footer_win = nil
+    win.output_was_at_bottom = output_was_at_bottom
+  end)
+end
+
 ---@param ratio number|nil
 function M.set_last_window_width_ratio(ratio)
   return store.set('last_window_width_ratio', ratio)
@@ -367,10 +372,12 @@ function M.inspect_hidden_buffers()
 end
 
 function M.clear_hidden_window_state()
-  store.set('_hidden_buffers', nil)
-  if _state.windows and not _state.windows.input_win and not _state.windows.output_win then
-    store.set('windows', nil)
-  end
+  return store.batch(function()
+    store.set('_hidden_buffers', nil)
+    if _state.windows and not _state.windows.input_win and not _state.windows.output_win then
+      store.set('windows', nil)
+    end
+  end)
 end
 
 ---@return boolean
diff --git a/lua/opencode/ui/autocmds.lua b/lua/opencode/ui/autocmds.lua
index 3b42e39d..a3a345cd 100644
--- a/lua/opencode/ui/autocmds.lua
+++ b/lua/opencode/ui/autocmds.lua
@@ -35,8 +35,7 @@ function M.setup_autocmds(windows)
         return
       end
       local state = require('opencode.state')
-      state.ui.set_last_code_window(vim.api.nvim_get_current_win())
-      state.ui.set_current_code_buf(vim.api.nvim_get_current_buf())
+      state.ui.set_code_context(vim.api.nvim_get_current_win(), vim.api.nvim_get_current_buf())
     end,
   })
 
diff --git a/lua/opencode/ui/renderer.lua b/lua/opencode/ui/renderer.lua
index 850d2a60..f28d3f0f 100644
--- a/lua/opencode/ui/renderer.lua
+++ b/lua/opencode/ui/renderer.lua
@@ -215,8 +215,7 @@ end
 
 ---Render question display as a fake part
 function M.render_question_display()
-  local config_module = require('opencode.config')
-  local use_vim_ui = config_module.ui.questions and config_module.ui.questions.use_vim_ui_select
+  local use_vim_ui = config.ui.questions and config.ui.questions.use_vim_ui_select
 
   if use_vim_ui then
     -- When using vim.ui.select, we don't render anything in the buffer
@@ -961,13 +960,13 @@ function M.on_permission_updated(permission)
     end
   end
 
-  local permissions = vim.deepcopy(state.pending_permissions)
-  if existing_index then
-    permissions[existing_index] = permission
-  else
-    table.insert(permissions, permission)
-  end
-  state.renderer.set_pending_permissions(permissions)
+  state.renderer.update_pending_permissions(function(permissions)
+    if existing_index then
+      permissions[existing_index] = permission
+    else
+      table.insert(permissions, permission)
+    end
+  end)
 
   permission_window.add_permission(permission)
 
@@ -1195,10 +1194,7 @@ function M._update_stats_from_message(message)
 
   local tokens = message.info.tokens
   if tokens and tokens.input > 0 and message.info.cost and type(message.info.cost) == 'number' then
-    state.renderer.set_stats(
-      tokens.input + tokens.output + tokens.cache.read + tokens.cache.write,
-      message.info.cost
-    )
+    state.renderer.set_stats(tokens.input + tokens.output + tokens.cache.read + tokens.cache.write, message.info.cost)
   elseif tokens and tokens.input > 0 then
     state.renderer.set_tokens_count(tokens.input + tokens.output + tokens.cache.read + tokens.cache.write)
   elseif message.info.cost and type(message.info.cost) == 'number' then
diff --git a/lua/opencode/ui/ui.lua b/lua/opencode/ui/ui.lua
index 27453b14..b99d41e6 100644
--- a/lua/opencode/ui/ui.lua
+++ b/lua/opencode/ui/ui.lua
@@ -162,10 +162,7 @@ function M.hide_visible_windows(windows)
   end
   state.ui.stash_hidden_buffers(snapshot)
   if state.windows == windows then
-    state.windows.input_win = nil
-    state.windows.output_win = nil
-    state.windows.footer_win = nil
-    state.windows.output_was_at_bottom = snapshot.output_was_at_bottom
+    state.ui.mark_windows_hidden(snapshot.output_was_at_bottom)
   end
 end
 
@@ -223,19 +220,17 @@ function M.restore_hidden_windows()
 
   state.ui.consume_hidden_buffers()
 
+  state.ui.set_windows({
+    input_buf = hidden.input_buf,
+    output_buf = hidden.output_buf,
+    footer_buf = footer_buf,
+    input_win = win_ids.input_win,
+    output_win = win_ids.output_win,
+    footer_win = nil,
+    output_was_at_bottom = hidden.output_was_at_bottom == true,
+    saved_width_ratio = state.last_window_width_ratio,
+  })
   local windows = state.windows
-  if not windows then
-    windows = {}
-    state.ui.set_windows(windows)
-  end
-  windows.input_buf = hidden.input_buf
-  windows.output_buf = hidden.output_buf
-  windows.footer_buf = footer_buf
-  windows.input_win = win_ids.input_win
-  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.ui.set_cursor_position('input', hidden.input_cursor)
   state.ui.set_cursor_position('output', hidden.output_cursor)
@@ -347,8 +342,7 @@ function M.create_windows()
   local autocmds = require('opencode.ui.autocmds')
 
   if not require('opencode.ui.ui').is_opencode_focused() then
-    state.ui.set_last_code_window(vim.api.nvim_get_current_win())
-    state.ui.set_current_code_buf(vim.api.nvim_get_current_buf())
+    state.ui.set_code_context(vim.api.nvim_get_current_win(), vim.api.nvim_get_current_buf())
   end
 
   -- Create new windows from scratch
diff --git a/tests/unit/state_spec.lua b/tests/unit/state_spec.lua
index a9b489c9..984b1e22 100644
--- a/tests/unit/state_spec.lua
+++ b/tests/unit/state_spec.lua
@@ -110,4 +110,65 @@ describe('opencode.state (observable)', function()
       state.messages = {}
     end)
   end)
+
+  it('batches notifications until commit', function()
+    local calls = {}
+    local messages_cb = function(key, newv, oldv)
+      table.insert(calls, { key = key, newv = newv, oldv = oldv })
+    end
+    local cost_cb = function(key, newv, oldv)
+      table.insert(calls, { key = key, newv = newv, oldv = oldv })
+    end
+
+    state.store.subscribe('messages', messages_cb)
+    state.store.subscribe('cost', cost_cb)
+
+    state.store.batch(function(store)
+      store.set('messages', { { id = 'batched' } })
+      store.set('cost', 12)
+      assert.same({ { id = 'batched' } }, state.messages)
+      assert.equals(12, state.cost)
+      assert.equals(0, #calls)
+    end)
+
+    vim.wait(50, function()
+      return #calls == 2
+    end)
+
+    assert.same('messages', calls[1].key)
+    assert.same({ { id = 'batched' } }, calls[1].newv)
+    assert.same('cost', calls[2].key)
+    assert.equals(12, calls[2].newv)
+
+    state.renderer.set_messages(nil)
+    state.renderer.set_cost(0)
+    state.store.unsubscribe('messages', messages_cb)
+    state.store.unsubscribe('cost', cost_cb)
+  end)
+
+  it('emits after mutating table state in place', function()
+    local called = false
+    local received
+    local cb = function(_, newv)
+      called = true
+      received = newv
+    end
+
+    state.renderer.set_messages({})
+    state.store.subscribe('messages', cb)
+
+    state.store.mutate('messages', function(messages)
+      table.insert(messages, { id = 'mutated' })
+    end)
+
+    vim.wait(50, function()
+      return called
+    end)
+
+    assert.is_true(called)
+    assert.same({ { id = 'mutated' } }, received)
+
+    state.renderer.set_messages(nil)
+    state.store.unsubscribe('messages', cb)
+  end)
 end)

From 16154df7ca5c6e236edc3a7889aafe864c8b0ec8 Mon Sep 17 00:00:00 2001
From: Francis Belanger <francis.belanger@gmail.com>
Date: Wed, 18 Mar 2026 13:13:52 -0400
Subject: [PATCH 3/8] feat(state): add server port setter and session helpers

---
 lua/opencode/context.lua       |  7 -------
 lua/opencode/image_handler.lua |  1 -
 lua/opencode/state/jobs.lua    |  7 +++++++
 lua/opencode/state/session.lua | 18 ++++++++++++++++++
 tests/minimal/init.lua         |  6 ++++--
 5 files changed, 29 insertions(+), 10 deletions(-)

diff --git a/lua/opencode/context.lua b/lua/opencode/context.lua
index e3e93d61..62a5506b 100644
--- a/lua/opencode/context.lua
+++ b/lua/opencode/context.lua
@@ -116,12 +116,10 @@ end
 -- Delegate global state management to ChatContext
 function M.add_selection(selection)
   ChatContext.add_selection(selection)
-  state.context.set_context_updated_at(vim.uv.now())
 end
 
 function M.remove_selection(selection)
   ChatContext.remove_selection(selection)
-  state.context.set_context_updated_at(vim.uv.now())
 end
 
 function M.clear_selections()
@@ -216,13 +214,11 @@ function M.add_file(file)
 
   file = vim.fn.fnamemodify(file, ':p')
   ChatContext.add_file(file)
-  state.context.set_context_updated_at(vim.uv.now())
 end
 
 function M.remove_file(file)
   file = vim.fn.fnamemodify(file, ':p')
   ChatContext.remove_file(file)
-  state.context.set_context_updated_at(vim.uv.now())
 end
 
 function M.clear_files()
@@ -231,12 +227,10 @@ end
 
 function M.add_subagent(subagent)
   ChatContext.add_subagent(subagent)
-  state.context.set_context_updated_at(vim.uv.now())
 end
 
 function M.remove_subagent(subagent)
   ChatContext.remove_subagent(subagent)
-  state.context.set_context_updated_at(vim.uv.now())
 end
 
 function M.clear_subagents()
@@ -249,7 +243,6 @@ end
 
 function M.load()
   ChatContext.load()
-  state.context.set_context_updated_at(vim.uv.now())
 end
 
 -- Context creation with delta logic (delegates to ChatContext)
diff --git a/lua/opencode/image_handler.lua b/lua/opencode/image_handler.lua
index f19d4a15..7ebf7dd7 100644
--- a/lua/opencode/image_handler.lua
+++ b/lua/opencode/image_handler.lua
@@ -150,7 +150,6 @@ function M.paste_image_from_clipboard()
 
   if success then
     context.add_file(image_path)
-    state.context.set_context_updated_at(os.time())
     vim.notify('Image saved and added to context: ' .. vim.fn.fnamemodify(image_path, ':t'), vim.log.levels.INFO)
     return true
   end
diff --git a/lua/opencode/state/jobs.lua b/lua/opencode/state/jobs.lua
index 288c521f..30f62988 100644
--- a/lua/opencode/state/jobs.lua
+++ b/lua/opencode/state/jobs.lua
@@ -31,6 +31,13 @@ function M.clear_server()
   return store.set('opencode_server', nil)
 end
 
+---@param port integer
+function M.set_server_port(port)
+  store.mutate('opencode_server', function(server)
+    server.port = port
+  end)
+end
+
 ---@param client OpencodeApiClient|nil
 function M.set_api_client(client)
   return store.set('api_client', client)
diff --git a/lua/opencode/state/session.lua b/lua/opencode/state/session.lua
index 76ca483e..14e716f3 100644
--- a/lua/opencode/state/session.lua
+++ b/lua/opencode/state/session.lua
@@ -41,4 +41,22 @@ function M.set_user_message_count(count)
   return store.set('user_message_count', count)
 end
 
+---Increment/decrement the message count for a session, clamped to >= 0
+---@param session_id string
+---@param delta integer
+function M.increment_user_message_count(session_id, delta)
+  store.mutate('user_message_count', function(counts)
+    local new_value = (counts[session_id] or 0) + delta
+    counts[session_id] = new_value >= 0 and new_value or 0
+  end)
+end
+
+---Update active_session without emitting a change event, used when a silent
+---in-place update is needed (e.g. session metadata refresh that must not
+---trigger a re-render)
+---@param session Session
+function M.update_silently(session)
+  store.set_raw('active_session', session)
+end
+
 return M
diff --git a/tests/minimal/init.lua b/tests/minimal/init.lua
index d7e3293a..b875b1a0 100644
--- a/tests/minimal/init.lua
+++ b/tests/minimal/init.lua
@@ -34,6 +34,8 @@ vim.opt.termguicolors = true
 
 require('opencode')
 
-if vim.treesitter and vim.treesitter.start then
-  vim.treesitter.start = function() end
+-- Safely stub out treesitter start during tests. Accessing `vim.treesitter`
+local ok, ts = pcall(require, 'vim.treesitter')
+if ok and ts and ts.start then
+  ts.start = function() end
 end

From b89831b46d803f6eff0bb8a4f925a3370a6ef1a8 Mon Sep 17 00:00:00 2001
From: Francis Belanger <francis.belanger@gmail.com>
Date: Wed, 18 Mar 2026 14:22:14 -0400
Subject: [PATCH 4/8] fix: set port

Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>
---
 lua/opencode/server_job.lua | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/lua/opencode/server_job.lua b/lua/opencode/server_job.lua
index f3b04817..9bda3734 100644
--- a/lua/opencode/server_job.lua
+++ b/lua/opencode/server_job.lua
@@ -293,8 +293,7 @@ function M.spawn_local_server(promise, port, hostname)
       log.notify(string.format('Started local server at %s', base_url), vim.log.levels.INFO)
       if url_port then
         local port_num = tonumber(url_port)
-        state.store.set_raw('opencode_server', state.opencode_server)
-        state.opencode_server.port = port_num
+        state.jobs.set_server_port(port_num)
         local server_pid = job and job.pid
         port_mapping.register(port_num, vim.fn.getcwd(), true, 'serve', nil, server_pid)
         log.debug(

From a79ccaa8b8ba702598bbaff2faa3ff373f65aa27 Mon Sep 17 00:00:00 2001
From: Francis Belanger <francis.belanger@gmail.com>
Date: Wed, 18 Mar 2026 15:50:01 -0400
Subject: [PATCH 5/8] fix(store): use deepcopy on mutate

---
 lua/opencode/state/store.lua | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lua/opencode/state/store.lua b/lua/opencode/state/store.lua
index b2e3f63f..d2b93988 100644
--- a/lua/opencode/state/store.lua
+++ b/lua/opencode/state/store.lua
@@ -210,7 +210,7 @@ function M.mutate(key, mutator)
   end
 
   local current = _state[key]
-  local old = vim.tbl_extend('force', {}, current)
+  local old = vim.deepcopy(current)
   mutator(current)
   queue_emit(key, current, old)
   return current

From ad4414200654ccb0a14d51b6b3c9933cc8f6953a Mon Sep 17 00:00:00 2001
From: Francis Belanger <francis.belanger@gmail.com>
Date: Wed, 18 Mar 2026 15:51:41 -0400
Subject: [PATCH 6/8] fix(store): typings

---
 lua/opencode/state/renderer.lua | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lua/opencode/state/renderer.lua b/lua/opencode/state/renderer.lua
index ab4c108f..66b884fd 100644
--- a/lua/opencode/state/renderer.lua
+++ b/lua/opencode/state/renderer.lua
@@ -23,7 +23,7 @@ function M.set_pending_permissions(permissions)
   return store.set('pending_permissions', permissions)
 end
 
----@param mutator fun(current_permissions: OpencodePermission[]): OpencodePermission[]
+---@param mutator fun(current_permissions: OpencodePermission[]): nil
 function M.update_pending_permissions(mutator)
   return store.mutate('pending_permissions', mutator)
 end

From 5c33926d4abdd1d743239f0919e2916e6cafd5af Mon Sep 17 00:00:00 2001
From: Francis Belanger <francis.belanger@gmail.com>
Date: Wed, 18 Mar 2026 15:52:24 -0400
Subject: [PATCH 7/8] fix: comment

Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>
---
 tests/minimal/init.lua | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tests/minimal/init.lua b/tests/minimal/init.lua
index b875b1a0..e9cb7a6c 100644
--- a/tests/minimal/init.lua
+++ b/tests/minimal/init.lua
@@ -34,7 +34,7 @@ vim.opt.termguicolors = true
 
 require('opencode')
 
--- Safely stub out treesitter start during tests. Accessing `vim.treesitter`
+-- Safely stub out treesitter during tests, using pcall(require, ...) so tests pass even if vim.treesitter is unavailable.
 local ok, ts = pcall(require, 'vim.treesitter')
 if ok and ts and ts.start then
   ts.start = function() end

From b87995db67b54337d7c580abdbdbc10b1c2ef8f1 Mon Sep 17 00:00:00 2001
From: Francis Belanger <francis.belanger@gmail.com>
Date: Wed, 18 Mar 2026 15:53:09 -0400
Subject: [PATCH 8/8] fix(jobs): ensure server before setting port

Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>
---
 lua/opencode/state/jobs.lua | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/lua/opencode/state/jobs.lua b/lua/opencode/state/jobs.lua
index 30f62988..12ffbfdd 100644
--- a/lua/opencode/state/jobs.lua
+++ b/lua/opencode/state/jobs.lua
@@ -33,8 +33,13 @@ end
 
 ---@param port integer
 function M.set_server_port(port)
-  store.mutate('opencode_server', function(server)
-    server.port = port
+  local server = store.get('opencode_server')
+  if not server then
+    error('Opencode server is not set; cannot set port')
+  end
+
+  store.mutate('opencode_server', function(s)
+    s.port = port
   end)
 end