local MEMSIZE=16
if not digiline then
 print("Digilines not found.")
 return
end
local oldprint=print
local function print(...)
 for k,v in ipairs({...}) do
  oldprint("[Test3D:T416] "..tostring(v))
 end
end
print("Loading.")

local function t416_digiline_receive(pos, node, channel, msg)
 print("Digiline: "..tostring(pos.x)..","..tostring(pos.y)..","..tostring(pos.z).."; Channel: "..tostring(channel).."; Message: "..tostring(msg))
 local meta = minetest.get_meta(pos)
 local mem = string.split(meta:get_string("mem"),"\n")
 local ms = ""
 local chan = meta:get_string("channel")
 local memoffset = meta:get_int("startaddr")
 if channel:sub(1,#chan) == chan and tonumber(channel:sub(#chan+1),16)+1-memoffset <= MEMSIZE and tonumber(channel:sub(#chan+1),16)+1-memoffset > 0 then
  local memaddr = tonumber(channel:sub(#chan+1),16)+1-memoffset
  if tostring(msg):lower() == "get" then
   digiline:receptor_send(pos, digiline.rules.default, channel, tonumber(mem[memaddr] or 0))
   print("Reading address "..tostring(memaddr)..": "..tostring(mem[memaddr]))
  else
   mem[memaddr] = tonumber(msg) or 0
   for k,v in ipairs(mem) do
    ms = ms .. tostring(v) .. "\n"
   end
   meta:set_string("mem",ms)
   print("Set address "..tostring(memaddr).." to "..tostring(tonumber(msg)))
  end
 end
end
print("Created T416 digiline function")

local function t416_set_meta(pos)
 local meta = minetest.get_meta(pos)
 local ms = ""
 for i = 1, MEMSIZE do
  ms = ms .. "0\n"
 end
 meta:set_string("mem",ms)
 meta:set_string("channel","Default")
 meta:set_int("startaddr",0)
 meta:set_string("formspec","size[5,12]\nlabel[0.4,0.5;T416 Memory Node (16 words)]\nfield[0.5,2;4,1;channel;Channel prefix;${channel}]\nfield[0.5,3;4,1;startaddr;Starting address;${startaddr}]\ntextarea[0.5,4;4,8;mem;Memory contents;${mem}]")
end
minetest.register_node("test3d_t416:t416", {
 description = "T416 Memory Node",
 tiles = {"t416-top.png","t416-top.png","t416-side.png","t416-side.png","t416-side.png","t416-side.png"},
 on_construct = t416_set_meta,
 groups = {snappy=1,choppy=2,oddly_breakable_by_hand=2,flammable=3},
 digiline = {
  receptor = {},
  effector = {
   action = t416_digiline_receive
  }
 },
 on_receive_fields = function(pos,_,fields,sender)
  if fields.channel == nil then return end
  local meta = minetest.get_meta(pos)
  fields.channel = fields.channel or ""
  meta:set_string("channel",fields.channel)
  meta:set_int("startaddr",tonumber(fields.startaddr))
 end
})
print("T416 node registered")