session.lua

-- session.lua
minetest.log("action", "[Session] Loaded session.lua")

local session_table = {}

local Session = {}
Session.__index = Session

function Session.fetch(playername)
  assert(playername, "Session.get: playername required")
  local sess = session_table[playername]
  if not sess then
    minetest.log("action", "[Session.get] Session at creation: " .. tostring(Session))
    minetest.log("action", "[Session.get] Session.touch at creation: " .. tostring(Session.touch))
    sess = setmetatable({
      state = {},
      form_data = {},
      created_at = os.time(),
      last_access = os.time(),
      playername = playername,
    }, Session)
    session_table[playername] = sess
    minetest.log("action", "[Session.get] sess metatable: " .. tostring(getmetatable(sess)))
    minetest.log("action", "[Session.get] sess.touch after metatable: " .. tostring(sess.touch))
  end
  return sess
end

function Session.destroy(playername)
  assert(playername, "Session.destroy: playername required")
  session_table[playername] = nil
end

-- Update last_access whenever real interaction occurs
function Session:touch()
  self.last_access = os.time()
end

function Session:get(key)
  minetest.log("action", ("[Session:get] player='%s' key='%s' self=%s"):format(
    tostring(self.playername), tostring(key), tostring(self)
  ))
  if not self or type(self) ~= "table" or not self.touch then
    minetest.log("error", "[Session:get] Invalid self! Likely called with dot, not colon. Stack:\n" .. debug.traceback())
    error("[Session:get] Method called incorrectly (should use colon): sess:get(key)")
  end
  self:touch()
  local val = self.state[key]
  minetest.log("action", ("[Session:get] player='%s' key='%s' => %s"):format(
    tostring(self.playername), tostring(key), tostring(val)
  ))
  return val
end

function Session:set(key, value)
  self:touch()
  self.state[key] = value
end

-- Combined get/set method, similar to PHP's Session IO sugar
function Session:io(key, value)
  if value ~= nil then
    self:set(key, value)
    return value    -- Only touch once
  else
    return self:get(key)
  end
end

function Session:get_form_data(form)
  self:touch()
  return self.form_data[form]
end

function Session:set_form_data(form, data)
  self:touch()
  self.form_data[form] = data
end

-- Optional: Expire sessions that are too old/inactive (GC utility)
function Session.expire_inactive(threshold_seconds)
  local now = os.time()
  for pname, sess in pairs(session_table) do
    if sess.last_access and now - sess.last_access > threshold_seconds then
      session_table[pname] = nil
      minetest.log("action", ("[Session] Expired session for player '%s'"):format(pname))
    end
  end
end

-- Optional: Enumerate sessions (for admin/debug)
function Session.list()
  local out = {}
  for pname, sess in pairs(session_table) do
    table.insert(out, {playername = pname, last_access = sess.last_access, created_at = sess.created_at})
  end
  return out
end

return Session