local log = nrequire("log.lua")
--As soon as the client connects, request the names of all the pac's on the server

--If the player dosen't have PAC3 installed, then overwrite all pac-related network events to display an error.
if pac == nil then
	local function no_pac_panic()
		error("CapsAdmin's PAC3 is required for items, please download it from somewhere (perferably the workshop!)")
	end
	local networkmsgs = {
		"artery_downloadpac",
		"artery_applypac",
		"artery_giveworldpacs",
		"artery_removepac"
	}
	for k,v in pairs(networkmsgs) do
		net.Receive(v,no_pac_panic)
	end
	no_pac_panic()
	return --Don't execute this file!
end

local CLIENT_PAC_DIR = "artery/client/pacs"

file.CreateDir(CLIENT_PAC_DIR)

local function loadpac(ent,name,hash)
	if (not ent) or (not ent:IsValid()) then
		timer.Simple(1,function()
			loadpac(ent,name,hash)
		end)
		return
	end
	print("Told to apply pac", name, "to ent", ent)
	local filepath = string.format(CLIENT_PAC_DIR .. "/%s.txt",name)
	local filetext = file.Read(filepath,"DATA")
	if ent.AttachPACPart == nil then
		pac.SetupENT(ent)
		if ent.AttachPACPart == nil then
			timer.Simple(1,function()
				loadpac(ent,name,hash)
			end)
			return
		end
	end
	if filetext and tonumber(util.CRC(filetext)) then
		print("The file on our local system is up to date, applying!")
		local pactbl = CompileString(string.format("return {%s}",filetext),name)()
		ent:AttachPACPart(pactbl)
	else--Cache is old, download the new pac!
		log.debug(string.format("File out of date (%d vs %d) Re-downloading...", filetext and tonumber(util.CRC(filetext)) or 0 , hash))
		net.Start("artery_requestpac")
		net.WriteString(name)
		net.SendToServer()
		--1 second is probably long enough to download a pac, right?
		timer.Simple(1,function()
			loadpac(ent,name,hash)
		end)
	end
end

local function unloadpac(ent,name,hash)
	local filepath = string.format(CLIENT_PAC_DIR .. "/%s.txt",name)
	local filetext = file.Read(filepath,"DATA")
	local pactbl = CompileString(string.format("return {%s}",filetext),name)()
	ent:RemovePACPart(pactbl)
end

net.Receive("artery_downloadpac",function()
	local pac_name = net.ReadString()
	local pac_txt = net.ReadString()
	local pac_hash = net.ReadUInt(32)
	log.debug(string.format("Received file %s with hash %d", pac_name, pac_hash))
	local filepath = string.format(CLIENT_PAC_DIR .. "/%s.txt",pac_name)
	file.Write(filepath,pac_txt)
end)

net.Receive("artery_applypac",function()
	local pac_ent = net.ReadEntity()
	local pac_name = net.ReadString()
	local pac_hash = net.ReadUInt(32)
	loadpac(pac_ent,pac_name,pac_hash)
end)

net.Receive("artery_giveworldpacs",function()
	local pactbl = net.ReadTable()
	for ent,pacnames in pairs(pactbl) do
		for name, hash in pairs(pacnames) do
			loadpac(ent,name,hash)
		end
	end
end)

net.Receive("artery_removepac",function()
	local pac_ent = net.ReadEntity()
	local pac_name = net.ReadString()
	local pac_hash = net.ReadUInt(32)
	unloadpac(pac_ent,pac_name,pac_hash)
end)