tmux.lua

---Provide `opencode` in a [`tmux`](https://github.com/tmux/tmux) pane in the current window.
---@class opencode.provider.Tmux : opencode.Provider
---
---@field opts opencode.provider.tmux.Opts
---
---The `tmux` pane ID where `opencode` is running (internal use only).
---@field pane_id? string
local Tmux = {}
Tmux.__index = Tmux
Tmux.name = "tmux"

---@class opencode.provider.tmux.Opts
---
---`tmux` options for creating the pane.
---@field options? string
---
---Focus the opencode pane when created. Default: `false`
---@field focus? boolean
---
---Auto-close the tmux pane when opencode exits. Default: `true`
---@field auto_close? boolean
--
---Allow `allow-passthrough` on the opencode pane.
-- When enabled, opencode.nvim will use your configured tmux `allow-passthrough` option on its pane.
-- This allows opencode to use OSC escape sequences, but may leak escape codes to the buffer
-- (e.g., "=31337;OK" appearing in your buffer).
--
-- Limitations of having allow-passthrough disabled in the opencode pane:
-- - can't display images
-- - can't use special (terminal specific; non-system) clipboards
-- - may have issues setting window properties like the title from the pane
--
-- If you enable this, consider also enabling `focus` to auto-focus the pane on creation,
-- which can help avoid OSC code leakage while opencode is sending escape sequences on startup.
--
-- Default: `false` (allow-passthrough is disabled to prevent OSC code leakage)
---@field allow_passthrough? boolean

---@param opts? opencode.provider.tmux.Opts
---@return opencode.provider.Tmux
function Tmux.new(opts)
  local self = setmetatable({}, Tmux)
  self.opts = opts or {}
  self.pane_id = nil
  return self
end

---Check if we're running in a `tmux` session.
function Tmux.health()
  if vim.fn.executable("tmux") ~= 1 then
    return "`tmux` executable not found in `$PATH`.", {
      "Install `tmux` and ensure it's in your `$PATH`.",
    }
  end

  if not vim.env.TMUX then
    return "Not running in a `tmux` session.", {
      "Launch Neovim in a `tmux` session.",
    }
  end

  return true
end

---Get the `tmux` pane ID where we started `opencode`, if it still exists.
---Ideally we'd find existing panes by title or command, but `tmux` doesn't make that straightforward.
---@return string|nil pane_id
function Tmux:get_pane_id()
  local ok = self.health()
  if ok ~= true then
    error(ok, 0)
  end

  if self.pane_id then
    -- Confirm it still exists
    if vim.fn.system("tmux list-panes -t " .. self.pane_id):match("can't find pane") then
      self.pane_id = nil
    end
  end

  return self.pane_id
end

---Create or kill the `opencode` pane.
function Tmux:toggle()
  local pane_id = self:get_pane_id()
  if pane_id then
    self:stop()
  else
    self:start()
  end
end

---Start `opencode` in pane.
function Tmux:start()
  local pane_id = self:get_pane_id()
  if not pane_id then
    -- Create new pane
    local detach_flag = self.opts.focus and "" or "-d"
    self.pane_id = vim.fn.system(
      string.format("tmux split-window %s -P -F '#{pane_id}' %s '%s'", detach_flag, self.opts.options or "", self.cmd)
    )
    local disable_passthrough = self.opts.allow_passthrough ~= true -- default true (disable passthrough)
    if disable_passthrough and self.pane_id and self.pane_id ~= "" then
      vim.fn.system(string.format("tmux set-option -t %s -p allow-passthrough off", vim.trim(self.pane_id)))
    end
  end
end

---Kill the `opencode` pane.
function Tmux:stop()
  local pane_id = self:get_pane_id()
  if pane_id and self.opts.auto_close ~= false then
    vim.fn.system("tmux kill-pane -t " .. pane_id)
    self.pane_id = nil
  end
end

---Find an `opencode` server running in a sibling pane of the current tmux window.
---@return opencode.cli.server.Server|nil
function Tmux:find_server()
  if self.health() ~= true then
    return nil
  end

  local session_window = vim.fn.system("tmux display-message -p '#{session_name}:#{window_index}'"):gsub("\n", "")
  local panes_output = vim.fn.system(string.format("tmux list-panes -t '%s' -F '#{pane_tty}'", session_window))

  for tty in panes_output:gmatch("[^\r\n]+") do
    local tty_short = tty:gsub("^/dev/", "")
    local ps_output = vim.fn.system(string.format("ps -t %s -o pid,command", tty_short))

    for line in ps_output:gmatch("[^\r\n]+") do
      local pid = line:match("^%s*(%d+).*opencode")
      if pid then
        local lsof = vim.fn.system(string.format("lsof -w -iTCP -sTCP:LISTEN -P -n -a -p %s", pid))
        local port = lsof:match(":(%d+) %(LISTEN%)")
        if port then
          local ok, path = pcall(require("opencode.cli.client").get_path, tonumber(port))
          if ok then
            return {
              pid = tonumber(pid),
              port = tonumber(port),
              cwd = path.directory or path.worktree,
            }
          end
        end
      end
    end
  end

  return nil
end

return Tmux