--[[
	A thing that kinda works like require, or at least, works how I wish require worked.
	calls hooks:
		artery_nrequire_defined
		artery_core_loaded
]]
if nrequire ~= nil then return end

local searchpaths = {
	{"gamemodes/artery/gamemode","GAME"},
	{"artery/global","DATA"},
	{"data/artery/global","GAME"},
}

--dir is a table of {string_path, string_directory}
local function TraverseFolder(dir,func)
	local find_path = table.concat({dir[1],"/*"},"")
	local files,directories = file.Find(find_path,dir[2])
	for k,v in pairs(files) do
		local callpath = table.concat({dir[1],"/",v},"")
		func({callpath,dir[2]})
	end
	for k,v in pairs(directories) do
		local npath = table.concat({dir[1],"/",v},"")
		TraverseFolder({npath,dir[2]},func)
	end
end

local function BuildIncludeTable(tbl)
	local output = {}
	for k,v in pairs(tbl) do
		local filepath = v[1]
		local fileloc = v[2]
		local pathparts = {}
		for part in filepath:gmatch("/?[%w_]+/") do
			local foldername = part:gsub("/$",""):gsub("^/","")
			pathparts[#pathparts+1] = foldername
		end
		local filename = filepath:gfind("[%w_]+%.[%w_]+$")()
		if output[filename] == nil then
			output[filename] = {}
		end
		local cursor = output[filename]
		for folder= #pathparts, 2, -1 do
			if cursor[pathparts[folder]] == nil then
				cursor[pathparts[folder]] = {}
			end
			cursor = cursor[pathparts[folder]]
		end
		assert(cursor[pathparts[1]] == nil, string.format("Found 2 files with the same path:\n\t%q",pathparts[1]))
		cursor[pathparts[1]] = v
	end
	return output
end

--Finds the number of elements in a table, even if it is not an array
local function tbllen(tbl)
	local count = 0
	for k,v in pairs(tbl) do count = count + 1 end
	return count
end

--[[
	Finds all the paths from a include table
]]
local function collect_paths(pretbl)
	local ret = {}
	for k,v in pairs(pretbl) do
		if v[1] == nil then
			local resp = collect_paths(v)
			for i,j in pairs(resp) do
				ret[#ret + 1] = j
			end
		else
			ret[#ret + 1] = string.format("%s (%s)",v[1],v[2])
		end
	end
	return ret
end

--[[
	Scans the prefix table built by rebuild_include_table to find the file path for the partial name of an included file.
	If two files are named the same, you will need to include part of the file path until it can be resolved.
]]
local function scan(pretbl, name)
	local pathparts = {}
	for part in name:gmatch("/?[%w_]+/") do
		pathparts[#pathparts + 1] = part:gsub("/$",""):gsub("^/","")
	end
	local filename = name:gfind("[%w_]+%.[%w_]+$")()
	assert(filename ~= nil,string.format("Could not file a filename for %q from parts: %s valid files are:\n\t%s",name,table.concat(pathparts,","),table.concat(collect_paths(pretbl),"\n\t")))
	local cursor = pretbl[filename]
	assert(cursor ~= nil,string.format("Scan did not find a file named %q.\n",filename))
	local rev = {}
	for i = 1, #pathparts do rev[#pathparts - i + 1] = pathparts[i] end
	for k,v in ipairs(rev) do
		if cursor == nil then error(string.format("Scan could not complete file path translation while translateing %q at %s",table.concat(rev,","),v)) end
		cursor = cursor[v]
	end
	while cursor ~= nil and #cursor ~= 2 do
		assert(type(cursor) ~= "nil",string.format("Could not find a valid file for path %q, file paths:\n\t%s",name,table.concat(collect_paths(pretbl),"\n\t")))
		assert(tbllen(cursor) == 1,string.format("Ambiguous scan, there are two or more paths that match %q\n\t%s\nSpecify more of the file path.",name,table.concat(collect_paths(cursor),"\n\t")))
		cursor = cursor[next(cursor)]
	end
	assert(type(cursor) ~= "nil", string.format("Could not find %s under %s, found under\n\t %s",filename,name, table.concat(collect_paths(pretbl[filename]),"\n\t")))
	return cursor
end

local paths = {}
for k,v in pairs(searchpaths) do
	TraverseFolder(v,function(n)
		paths[#paths + 1] = n
	end)
end
local ntbl = BuildIncludeTable(paths)

local reqtbl = {} --Holds already nrequire()'d things
local lastcall = {} --Holds when things were loaded
local deptbl = {} --Holds the dependencies between files
local pathstack = {}
function nrequire(req,...)
	
	
	local tpath = scan(ntbl,req) -- Find the full path for the nrequired() module
	
	local trace = debug.getinfo(1,"flnSu")
	local source = trace.source
	deptbl[source] = tpath
	
	--If we've already run it, just return it
	if reqtbl[tpath[1]] then
		return reqtbl[tpath[1]]
	end
	
	--Otherwise, make sure we don't have a circular depedency
	for k,v in pairs(pathstack) do
		assert(v ~= tpath[1],string.format("Circular dependancy detected:\n\t%s\n\t\t|\n\t\tV\n\t%s",table.concat(pathstack,"\n\t\t|\n\t\tV\n\t"),v))
	end
	
	--Actually run the file
	pathstack[#pathstack + 1] = tpath[1]
	local filetxt = file.Read(tpath[1],tpath[2])
	local filetime = file.Time(tpath[1],tpath[2])
	local filefunc = CompileString(filetxt,tpath[1],false)
	if type(filefunc) ~= "function" then
		error(filefunc)
	else
		xpcall(function()
			local m = filefunc()
			hook.Run("artery_file_included",tpath,m)
			reqtbl[tpath[1]] = m
			lastcall[tpath[1]] = filetime
		end,function(err)
			MsgC(Color(209,96,196),"nrequire Error:",err,"\n")
		end)
	end
	pathstack[#pathstack] = nil
	
	return reqtbl[tpath[1]]
	
end

--[[
	Automatically include all the files in the gamemode directory based on the file name.
	If the file starts with cl_ it will only be included on the client, if it starts with sv_ it will only be included on the server. If it starts with anything else, it will be shared. Will detect and error on circuar dependancy.
]]
local function doincludes()
	paths = {}
	for k,v in pairs(searchpaths) do
		TraverseFolder(v,function(n)
			paths[#paths + 1] = n
		end)
	end
	ntbl = BuildIncludeTable(paths)
	reqtbl = reqtbl or {}
	for k,v in pairs(paths) do
		local filename = v[1]
		MsgN("Filename:",filename)
		if filename == "gamemodes/artery/gamemode/init.lua" then
			continue
		end
		if filename:match("/?sv_[%w_]+%.[%w_]+$") then
			if SERVER then
				nrequire(filename)
			end
		elseif filename:match("/?cl_[%w_]+%.[%w_]+$") then
			if CLIENT then
				nrequire(filename)
			else
				AddCSLuaFile(filename)
			end
		else
			if SERVER then
				AddCSLuaFile(filename)
			end
			nrequire(filename)
		end
		pathstack = {}
	end
end

doincludes()

concommand.Add("PrintDepTbl",function(ply,cmd,args)
	PrintTable(deptbl)
end)
concommand.Add("PrintReqTbl",function(ply,cmd,args)
	PrintTable(reqtbl)
end)

if SERVER then
	util.AddNetworkString("art_refresh")
	concommand.Add("art_manualrefresh",function(ply,cmd,args)
		if not ply:IsAdmin() then return end
		reqtbl = {}
		doincludes()
		net.Start("art_refresh")
		net.Broadcast()
	end)
end
if CLIENT then net.Receive("art_refresh",doincludes) end

concommand.Add("artery_manualrefresh",function(ply,cmd,args)
	doincludes()
end)