Instead of the scripts running in the same Lua process as the one of your game, Anselme can run in a Client-Server mode. This allows:

* Anselme to run in a separate thread and therefore not affect your game's frame times (Anselme is not very fast)
* to use Anselme other game engine that don't use Lua

The _server_ is the process that holds and process the Anselme state. Typically, the server would run in a separate process or thread that your game.

The _client_ connects to a server and sends instructions to execute Anselmes scripts and receive the response. Typically, the client correspond to your game.

For now, the whole system assumes that there is a single client per server - so you should not share a single server among serveral client.

How the Client and Server communicate between each other is defined using a RPC object.
Out-of-the-box, Anselme provides RPC objects that can communicate over [LÖVE](https://www.love2d.org/) threads, and over [JSON-RPC 2.0](https://www.jsonrpc.org/specification); these can be easily created using the functions in [anselme.server](#anselme_server).
If you want to implement a custom RPC mechanism, you can look at the existing implementations in `anselme/server/rpc/`.

Example usage in a LÖVE game:
```lua
local server = require("anselme.server")

-- create a new client+server
local client = server.new_love_thread()
client:load_stdlib()

-- load an anselme script file in a new branch
local run_state = client:branch("block")
run_state:run_file("script.ans")

-- start script
run_state:step(handle_event)

-- callback to handle an anselme event
function handle_event(event, data)
	if event == "text" then
		show_dialog_box {
			lines = data,
			on_dialog_box_closed = function()
				run_state:step(handle_event) -- resume script
			end
		}
	elseif event == "choice" then
		show_choice_dialog_box {
			choices = data,
			on_dialog_box_closed = function(choice_number)
				run_state:choose(choice_number)
				run_state:step(handle_event)
			end
		}
	elseif event == "return" then
		run_state:merge()
		run_state:remove() -- remove branch from server
	elseif event == "error" then
		print("error in anselme thread!", data)
		run_state:remove()
	end
end

function love.update()
	client:process() -- handle messages coming from the server
end
```

# anselme.server

{{anselme/server/init.lua}}

# Client

{{anselme/server/Client.lua}}

# Server

{{anselme/server/Server.lua}}