feat(cli): picker to choose new/continue/resume on launch

lua/sidekick/cli/init.lua

@@ -12,6 +12,8 @@ local M = {}
 ---@field prompt? string
 ---@field text? sidekick.Text[]
 
+---@alias sidekick.cli.Mode "new"|"continue"|"resume"
+
 ---@class sidekick.cli.Config
 ---@field cmd string[] Command to run the CLI tool
 ---@field env? table<string, string|false> Environment variables to set when running the command
@@ -21,12 +23,15 @@ local M = {}
 ---@field mux_focus? boolean wether the tool needs to be focused in order to receive input
 ---@field format? fun(text:sidekick.Text[], str:string):string?
 ---@field native_scroll? boolean whether the tool handles scrolling natively
+---@field continue? string[] Extra args appended to `cmd` to continue the most recent session
+---@field resume? string[] Extra args appended to `cmd` to resume a session (typically via the tool's own picker)
 
 ---@class sidekick.cli.Show
 ---@field name? string
 ---@field focus? boolean
 ---@field filter? sidekick.cli.Filter
 ---@field all? boolean
+---@field mode? sidekick.cli.Mode|false mode used when starting a new session (bypasses the picker)
 
 ---@class sidekick.cli.Hide
 ---@field name? string
@@ -91,6 +96,7 @@ function M.show(opts)
     attach = true,
     filter = opts.filter,
     focus = opts.focus,
+    mode = opts.mode,
     show = true,
   })
 end
@@ -112,6 +118,7 @@ function M.toggle(opts)
   end, {
     attach = true,
     filter = opts.filter,
+    mode = opts.mode,
   })
 end
 

lua/sidekick/cli/session/init.lua

@@ -75,10 +75,18 @@ function B.sessions()
   error("Backend:sessions() not implemented")
 end
 
----@param state sidekick.cli.session.Opts
+---@param state sidekick.cli.session.Opts|{mode?:sidekick.cli.Mode}
 function M.new(state)
   local tool = state.tool
   tool = type(tool) == "string" and Config.get_tool(tool) or tool --[[@as sidekick.cli.Tool]]
+  local mode = state.mode --[[@as sidekick.cli.Mode?]]
+  if mode and mode ~= "new" then
+    local extra = tool.config[mode]
+    if extra and #extra > 0 then
+      local cmd = vim.list_extend(vim.deepcopy(tool.cmd), extra)
+      tool = tool:clone({ cmd = cmd })
+    end
+  end
   local backend = state.backend or (Config.cli.mux.enabled and Config.cli.mux.backend or "terminal")
   local super = assert(M.backends[backend], "unknown backend: " .. backend)
   local meta = getmetatable(state)

lua/sidekick/cli/state.lua

@@ -13,6 +13,7 @@ local M = {}
 ---@field session? sidekick.cli.Session
 ---@field started? boolean
 ---@field terminal? sidekick.cli.Terminal
+---@field mode? sidekick.cli.Mode
 
 ---@class sidekick.cli.Filter
 ---@field attached? boolean
@@ -30,6 +31,7 @@ local M = {}
 ---@field focus? boolean
 ---@field attach? boolean
 ---@field all? boolean
+---@field mode? sidekick.cli.Mode|false
 
 ---@param t sidekick.cli.State
 ---@param filter? sidekick.cli.Filter
@@ -137,6 +139,45 @@ function M.get(filter)
   return ret
 end
 
+---@param tool sidekick.cli.Tool
+---@param cb fun(mode?: sidekick.cli.Mode)
+---@param forced? sidekick.cli.Mode|false
+local function pick_mode(tool, cb, forced)
+  local has_continue = type(tool.config.continue) == "table" and #tool.config.continue > 0
+  local has_resume = type(tool.config.resume) == "table" and #tool.config.resume > 0
+  if not (has_continue or has_resume) then
+    return cb(nil)
+  end
+  local default = forced == nil and Config.cli.resume or forced
+  if default == false or default == "new" then
+    return cb(nil)
+  elseif default == "continue" and has_continue then
+    return cb("continue")
+  elseif default == "resume" and has_resume then
+    return cb("resume")
+  end
+  local choices = { "new" } ---@type sidekick.cli.Mode[]
+  if has_continue then
+    choices[#choices + 1] = "continue"
+  end
+  if has_resume then
+    choices[#choices + 1] = "resume"
+  end
+  local labels = {
+    new = "new session",
+    continue = "continue most recent session",
+    resume = "resume a session (pick in tool)",
+  }
+  vim.ui.select(choices, {
+    prompt = ("Start `%s`:"):format(tool.name),
+    format_item = function(m)
+      return labels[m]
+    end,
+  }, function(choice)
+    cb(choice)
+  end)
+end
+
 --- Executes a callback with one or more attached sessions.
 ---@param cb fun(state: sidekick.cli.State, attached?: boolean):any?
 ---@param opts? sidekick.cli.With
@@ -149,8 +190,18 @@ function M.with(cb, opts)
     if not state then
       return
     end
-    local ret, attached = M.attach(state, { show = opts.show, focus = opts.focus })
-    cb(ret, attached)
+    local function proceed()
+      local ret, attached = M.attach(state, { show = opts.show, focus = opts.focus })
+      cb(ret, attached)
+    end
+    if state.session == nil then
+      pick_mode(state.tool, function(mode)
+        state.mode = mode
+        proceed()
+      end, opts.mode)
+    else
+      proceed()
+    end
   end)
 
   local filter_attached = Util.merge(opts.filter, { attached = true })
@@ -182,7 +233,7 @@ function M.attach(state, opts)
   local tool = state.tool
 
   -- if the session is already attached, the below is a no-op
-  local session = state.session or Session.new({ tool = tool.name })
+  local session = state.session or Session.new({ tool = tool.name, mode = state.mode })
   session = Session.attach(session)
 
   state = M.get_state(session) -- update state

lua/sidekick/config.lua

@@ -33,6 +33,10 @@ local defaults = {
   -- Work with AI cli tools directly from within Neovim
   cli = {
     watch = true, -- notify Neovim of file changes done by AI CLI tools
+    -- When starting a tool that supports resume/continue, pick how to start it:
+    -- "ask" (default): show a picker when the tool has `continue` or `resume` defined
+    -- "new" / "continue" / "resume": always start with that mode, no picker
+    resume = "ask", ---@type "ask"|"new"|"continue"|"resume"
     ---@class sidekick.win.Opts
     win = {
       --- This is run when a new terminal is created, before starting it.