Add Lua support

[AJenbo]

A very basic Lua integration that just links it in the most lame way possible (to see what platforms build) and adds a single event and a way to print message to the player.

The game will look for lua/user.lua on boot up. If you provide the following:

local function OnGameStart()
    devilutionx.message("Hello from " .. _VERSION)
end

Events.OnGameStart.Add(OnGameStart)

You get this once the game loads:

The event system is somewhat based on the one from Project Zomboid https://pzwiki.net/wiki/Lua_Events/OnGameStart
Thought a good portion of it is implemented via Lua so mods can register and trigger there own events.

[heinermann]

If this uses a limited API for security reasons (i.e. later down the road a mod manager etc), you'll probably want an "unsafe mode" switch to unlock the filesystem and other things (for i.e. integrations such as Twitch and Archipelago).

[AJenbo]

If this uses a limited API for security reasons (i.e. later down the road a mod manager etc), you'll probably want an "unsafe mode" switch to unlock the filesystem and other things (for i.e. integrations such as Twitch and Archipelago).

limited API? unsafe mode? Archipelago?

[heinermann]

If this uses a limited API for security reasons (i.e. later down the road a mod manager etc), you'll probably want an "unsafe mode" switch to unlock the filesystem and other things (for i.e. integrations such as Twitch and Archipelago).

limited API? unsafe mode? Archipelago?

Games like Factorio and Noita limit/restrict the API for security reasons, as people can enable many mods through a simple one-click solution via some mod manager or Steam. I don't know if that's something you wanted to do or not. Some games like Starbound and Noita have a switch that you can enable to allow "unsafe" mods (usually called "unsafe mode", "allow unsafe mods", or "unrestrict lua API" etc). Archipelago.

[AJenbo]

Yes, a way to enable multiple mods would be an eventual goal.
I'm not sure if you would consider what we have restricted mode, or what you would be missing from an unsafe mode, so for now we are just starting with the default and can evolve from there as needed.

[heinermann]

It's unrestricted by default I think. A restricted mode would restrict or modify some of the main functions such as require to disallow DLLs or going up one level in a path. io, os, and package would be inaccessible parts of the lua lib. But yeah that stuff can just come later.

[StephenCWills]

Looks awesome.