---Various functions for npcs.
-- Helps you spawn monsters, townies, and shopkeepers
--@server sv_npcsystem.lua
--@alias n

local f = nrequire("concommands.lua")
local log = nrequire("log.lua")
local n = {}
local npcs = {} --Master table of npcs
local npc_metas = {}
local autocompletef

function npc_tostring(npctbl)
	return function(self)
		return string.format("<NPC %q : %s",npctbl.Name,self.Name)
	end
end

---Registers an NPC.
-- Adds an npc to the global table. NPC's should have unique .Name fields, if they don't, this function will error.
--@see npctbl
--@tparam table npc The npc's table.
function n.RegisterNPC(npc)
	assert(npc ~= nil, "Attempted to register a nil npc")
	assert(type(npc) == "table", "Attempted to regsiter an npc that was not a table, it was a " .. type(npc))
	assert(npc.Name ~= nil, "Attempted to register an npc without a name")
	log.info("Added npc:",npc.Name)
	npcs[npc.Name] = npc
	npc_metas[npc.Name] = {__index = npc, __tostring = npc_tostring(npc)}
	autocompletef = f.AutocompleteFunction(npcs)
end

function n.GetNPC(name)
	assert(npcs[name] ~= nil, "Tried to get npc without name")
	return npcs[name]
end

--Ents to remove when refreshing the npc map
local removeents = {"art_npc", "info_townienode", "npc_shop"}

if SERVER then
	---Creates an NPC.
	-- Creates an npc, by name
	--@tparam string npcname The npc's name
	--@tparam vector3 pos The position to spawn the npc
	function n.CreateNPCByName(npcname, pos)
		assert(npcs[npcname],string.format("No npc named %q, valid names are:\n%s",npcname,table.concat(table.GetKeys(npcs),"\n")))
		--print("Createing a ", npcname, " at ", pos)
		local npc = {Pos = pos}
		setmetatable(npc,npc_metas[npcname])
		npc:Spawn()
		return npc
	end

	---Creats a shop npc.
	-- Creates a shop npc from a shop npc table
	--@see shopnpctbl
	--@tparam table npc The shop npc's table.
	function n.CreateShop(npc)
		local npc = {}
		setmetatable(npc,npc_metas["Shopkeep"])
		npc:Spawn()
		return npc
	end

	---Creates a townie.
	-- Creates a new townie that wanders around his areas of intrest
	--@see townienpctbl
	--@tparam table npc The townie npc's table.
	function n.CreateTownie(tbl)
		local npc = {}
		setmetatable(tbl,npc_metas["Townie"])
		npc:Spawn()
		return npc
	end

	---Create an area of intrest.
	-- Creates an point that you can use in a townie's locations of intrest.
	--@see navnodetbl
	--@tparam table tbl The table for the nav node
	function n.CreateNavNode(tbl)
		local nodeent = ents.Create("info_townienode")
		assert(tbl ~= nil, "Tried to create a nil navnode")
		for k, v in pairs(tbl) do
			nodeent[k] = v
		end
		nodeent:Spawn()
	end

	for k, v in pairs(removeents) do
		local eot = ents.FindByClass(v)
		for i, j in pairs(eot) do
			j:Remove()
		end
	end
end

local function ExecuteOnFolder(dir, recursive, func)
	local path = ""
	local fpath = table.concat({path,dir,"/*"})
	local files, directories = file.Find(fpath,"DATA")
	for k,v in pairs(files) do
		local callpath = table.concat({path,dir,"/",v})
		func(callpath)
	end
	if not recursive then return end
	for k,v in pairs(directories) do
		local npath = table.concat({dir,"/",v})
		ExecuteOnFolder(npath,true,func)
	end
end

local function loadMap()
	local mapname = game.GetMap()

	local foldername = "artery/maps/" .. mapname
	ExecuteOnFolder(foldername,true,function(path)
		local filename = path:match("/([^/]+)$")
		print("I want to run",path, ";", filename)
		local is_server = filename:match("^sv_")
		local is_client = filename:match("^cl_")
		if (is_client and CLIENT) or (is_server and SERVER) or (not is_server and not is_client) then
			local filetxt = file.Read(path,"DATA")
			--print("File text is", filetxt)
			CompileString(filetxt,path)()
			--print("I want to execute",path)
		end
	end)
end

hook.Add("InitPostEntity", "artery_spawnmapnpcs", function()
	loadMap()
end)

---Reloads the entities on the map.
-- Removes and then reload all of the entities on the level
--@concommand artery_reloadmap
concommand.Add("artery_reloadmap", function(ply,cmd,args)
	if not ply:IsAdmin() then return end
	for k, v in pairs(removeents) do
		local eot = ents.FindByClass(v)

		for i, j in pairs(eot) do
			j:Remove()
		end
	end

	loadMap()
end)

---Create a new npc.
-- Creates a new npc a the point the player is looking
--@usage artery_makenpc <npc_name>
--@concommand artery_makenpc
concommand.Add("artery_makenpc", function(ply, cmd, args)
	if not ply:IsAdmin() then return end
	local na = args[1]
	n.CreateNPCByName(na, ply:GetEyeTrace().HitPos)
end, autocompletef)

return n