MQTT send receive.lua

--[[ CHANGE TO SUIT ENVIRONMENT --]]
local mqttBroker = '192.168.10.21'
local mqttUsername = 'mqtt'
local mqttPassword = 'password'
local lighting = { ['56'] = true, } -- Array of applications that are used for lighting (do not remove should lastLevel not be required)
local checkForChanges = true       -- When true the script will periodically check for create/update/delete of object keywords (disable to lower CPU load, and manually restart on keyword change)
local checkChanges = 30            -- Interval in seconds to check for changes to object keywords

--[[ SET AS APPROPRIATE TO SUIT ENVIRONMENT --]]
local entityIdAsIndentifier = true -- If true then entity IDs will be created using the object identifier (e.g. light.bathroom_1_fan), and if false using C-Bus numbering (e.g. light.cbus_mqtt_254_56_10)
local forceChangeId = true         -- CAUTION!!! If true, then if the entity ID changes (because entityIdAsIndentifier) then the entities will be removed and re-added, forcing the entity ID to change - this WILL break dashboards/automations/etc.
local removeSaFromStartOfPn = false -- If true then the suggested area will be removed from the beginning of the preferred name (if the pn includes it) - add the keyword 'exactpn' to create an exception when true
local useLastLevel = false         -- Whether to store and use lastLevel (these days Home Assistant recalls previous 'on' levels for most things, but not some things, so lastLevel is always used for certain objects, like fan)
local airtopiaSupport = false      -- Monitor keyword 'AT' for Airtopia devices - set to true if support is desired
local panasonicSupport = false     -- Monitor keyword 'AC' for Panasonic devices - set to true if support is desired
local environmentSupport = false   -- Monitor keyword 'ENV' for ESPHome environment sensors - set to true if support is desired

--[[
  ** NOTE: This script at one stage relied on an event-based script 'MQTT final' or 'MQTT'. This event script is no longer needed, and can be deleted.
  ** If named correctly, this resident script will disable the event-based script on startup, but even if it is enabled it will not cause any issue.\
--]]

--[[
Resident, zero sleep interval, name: 'MQTT send receive'

Manage CBus, Panasonic and Airtopia AC and environment events for MQTT, and publish discovery topics. Used with Home Assistant.

Documentation available at https://github.com/autoSteve/acMqtt
--]]

--[[
General configuration variables follow. Change as required, but probably no need to.
--]]
local logging = false        -- Enable detailed logging
local logms = false          -- Display timestamp duration of certain operations

local setCoverLevelAtStop = true -- As the name implies, for tracked covers in level translation mode, set the stop value to the estimated level at stop
local sendHeartbeat = 30     -- Send a heartbeat to the 'Heartbeat' script every n seconds (zero to disable heartbeat)
local heartbeatConditions = { max = 120, } -- At most 120 seconds without a heartbeat or else get restarted
local publishNoLevel = false -- For trigger app, whether to publish a level with no tag as "Level n" or raise an error in the log
local selectExact = true     -- For select, if a CBus level other than in the select levels is set then adjust the CBus level to the next higher select level
local blindKey               -- If blind fully open is desirable instead of lastlevel, then change to a string contained in every blind object (e.g. 'Blind'), case sensitive
local mqttClientId = 'ac2mqtt' -- The Mosquitto client ID, which must be unique on the broker - this can be set to nil, in which case a unique name will automatically be generated by the broker
local mqttQoS = 2            -- Quality of service for MQTT messages: 0 = only once, 1 = at least once, 2 = exactly once
local mqttJunk = true        -- Whether to publish junk before a blank publish message when removing topics (not necessary, but cleans up MQTT Explorer view)

--[[
Timing variables. Adjust to taste if you know what you're doing. These provide a good compromise, but your deployment may vary.
--]]
local busTimeout = 0.1       -- Lower = higher CPU, but better responsiveness (0.05 = 1/20th of a second or 50ms, 0.005 = 5ms)
local mqttTimeout = 0        -- In milliseconds, go with zero unless you know what you're doing
local ignoreTimeout = 2      -- Timeout for stale MQTT ignore messages in seconds (two seconds is a long time...)

--[[
Topic prefixes for read/write/publish. The mqttDiscovery topic is recommended to be set to 'homeassistant/'
for use with HA, which is the default here. The MQTT CBus topics can be called whatever you want, as discovery/subscribe
adjusts. All topic prefixes must end in '/'.
--]]
local mqttCbus = 'cbus/'
local mqttReadTopic = mqttCbus..'read/'
local mqttWriteTopic = mqttCbus..'write/'
local mqttDiscoveryTopic = 'homeassistant/'

--[[
Variables not to be messed with unless you definitely know what you're doing.
--]]
local init = true            -- Initialisation
local reconnect = false      -- Reconnection does not perform a full publish
local discovery = {}         -- MQTT discovery topics lookup
local discoveryDelete = {}   -- If duplicate discovery topics are detected on startup then they will be removed
local discoveryName = {}     -- Device names (used for rename detection)
local discoveryId = {}       -- Device obj_id (used for rename detection)
local mqttDevices = {}       -- CBus groups to send MQTT topics for
local ac = {}                -- Panasonic AC device details
local acDevices = {}         -- Quick lookup to determine whether an object is an AC device
local acBoards = {}          -- All physical AC boards (esp32)
local acSense = {}           -- Quick lookup for AC sensors
local at = {}                -- Airtopia device details
local atDevices = {}         -- Quick lookup to determine whether an object is an AT device
local atBoards = {}          -- All physical AT boards
local atDiscovery = {}       -- AT discovery topics lookup
local atDiscoveryDelete = {} -- If duplicate discovery topics are detected on startup then they will be removed
local env = {}               -- Environment device details
local envDevices = {}        -- Quick lookup to determine whether an object is an environment device
local envBoards = {}         -- All physical environment boards (esp32)
local cbusMessages = {}      -- Message queue
local mqttMessages = {}      -- Message queue
local ignoreCbus = {}        -- To prevent message loops
local ignoreMqtt = {}        -- To prevent message loops
local triggers = {}          -- Trigger groups and their levels
local selects = {}           -- Select groups and their options/levels
local inbound = {}           -- Sensors from Home Assistant
local cover = {}             -- Quick lookup to determine whether an object is a cover (blind)
local fan = {}               -- Quick lookup to determine whether an object is a fan (sweep fan)
local bSensor = {}           -- Quick lookup to determine whether an object is a bsensor (a regular lighting group acting as status)
local binarySensor = {}      -- Quick lookup to determine whether an object is a binary sensor
local button = {}            -- Quick lookup to determine whether an object is a button
local lightingButton = {}    -- Quick lookup to determine whether an object is a lighting group as a button
local userParameter = {}     -- Quick lookup to determine whether an object is a user parameter
local unitParameter = {}     -- Quick lookup to determine whether an object is a unit parameter
local storeLevel = {}        -- Force store the last level for certain object types (fan, fan_pct)
local publishAdj = {}        -- Holds scale and decimals to apply
local includeUnits = {}      -- Holds table of booleans to add sensor unit (%, $, °C, etc.) to MQTT value
local transition = {}        -- Covers that are transitioning
local unpublished = {}       -- The outstanding set of CBus objects to publish discovery topics for
local unpublishedAt = {}     -- The outstanding set of CBus Airtopia objects to publish discovery topics for
local mqttStatus = 2         -- The status of the MQTT connection. Initially disconnected, which will cause an immediate connection. 1=connected, 2=disconnected
local mqttConnected = 0      -- Timestamp of MQTT connection
local imgDefault = {         -- Defaults for images - Simple image name, or a table of 'also contains' keywords (which must include an #else entry)
  heat            = 'mdi:radiator',
  blind           = 'mdi:blinds',
  ['under floor'] = {enable = 'mdi:radiator-disabled', ['#else'] = 'mdi:radiator'},
  ['towel rail']  = {enable = 'mdi:radiator-disabled', ['#else'] = 'mdi:radiator'},
  fan             = {sweep = 'mdi:ceiling-fan', ['#else'] = 'mdi:fan'},
  exhaust         = 'mdi:fan',
  gate            = {open = 'mdi:gate-open', ['#else'] = 'mdi:gate'},
  pir             = 'mdi:motion-sensor',
  temperature     = 'mdi:thermometer',
}
local acMsg = { climate = true, select = true, sensor = true, }
local cudRaw = {             -- All possible keywords for MQTT types, used in CUD function to exclude unrelated keywords for change detection
  'MQTT', 'light', 'switch', 'cover', 'fan', 'fan_pct', 'fanpct', 'sensor', 'binary_sensor', 'binarysensor', 'bsensor', 'isensor', 'button', 'select',
  'pn=', 'sa=', 'img=', 'unit=', 'class=', 'dec=', 'scale=', 'on=', 'off=', 'lvl=', 'rate=', 'delay=', 'topic=',
  'includeunit', 'preset', 'noleveltranslate', 'exactpn',
}
local cudAll = {} local param for _, param in ipairs(cudRaw) do cudAll[param] = true end cudRaw = nil

-- local coverLevel = {} storage.set('coverLevel', coverLevel) -- Clear stored coverLevel
local coverLevel = storage.get('coverLevel', {}) -- Holds the current level of covers (survives restart)
local lastLevel = storage.get('lastlvl', {}) -- Holds any last levels if desired/forced (survives restart)

local airtopiaCmds = { 'power', 'fan', 'swing', 'mode', 'target_temperature', } -- All command topics (used for clean up)
local atmodes = { 'auto', 'cool', 'heat', 'fan_only', 'dry', 'off', } -- Airtopia modes
local atswings = { 'Off', 'Horizontal only', 'Vertical only', 'Horizontal and Vertical', } -- Airtopia swing modes
local atfans = { 'Auto', '1', '2', '3', '4', } -- Airtopia fan speed (THIS IS UNTESTED, will result in 0, 1, 2, 3, 4 being set in the user parameter in the order of the table)
local airtopiaStates = {}    -- Current state topics in use (used for clean up)

local RETAIN = true          -- Boolean aliases for MQTT retain and no-retain settings
local NORETAIN = false

local started = socket.gettime()
local heartbeat = started

-- Runtime global variable checking. Globals must be explicitly declared, which will catch variable name typos
local declaredNames = { vprint = true, vprinthex = true, maxgroup = true, mosquitto = true, rr = true, _ = true, }
local function declare(name, initval) rawset(_G, name, initval) declaredNames[name] = true end
local exclude = { ngx = true, }
setmetatable(_G, {
  __newindex = function (t, n, v) if not declaredNames[n] then log('Warning: Write to undeclared global variable "'..n..'"') end rawset(t, n, v) end,
  __index = function (_, n) if not exclude[n] and not declaredNames[n] then log('Warning: Read undeclared global variable "'..n..'"') end return nil end,
})

--[[
Utility funtions
--]]

local function len(tbl) local i = 0 for _, _ in pairs(tbl) do i = i + 1 end return i end -- Get number of table members
local function hasMembers(tbl) for _, _ in pairs(tbl) do return true end return false end -- Get whether any table members
string.contains = function (text, prefix) local pos = text:find(prefix, 1, true); if pos then return pos >= 1 else return false end end -- Test whether a string contains a substring, ignoring nil
--string.trim = function (s) if s ~= nil then return s:match('^%s*(.-)%s*$') else return nil end end -- Remove leading and trailing spaces
local function sleep(sec) socket.select(nil, nil, sec) end
local function tNetCBus(net) if net == 0 then return 254 else return net end end -- Translate AC network numbering to CBus
local function indexOf(array, value) for i, v in ipairs(array) do if v == value then return i end end return nil end -- Find the index number of an array member
local function lastSlashToUnderscore(alias) local cnt alias, cnt = alias:gsub('/', '_') return alias:gsub('_', '/', cnt-1) end -- Convert the last slash character to an underscore
local function copy(obj, seen) -- Copy tables, 'seen' is for recursive use
  if type(obj) ~= 'table' then return obj end
  if seen and seen[obj] then return seen[obj] end
  local s = seen or {}
  local res = setmetatable({}, getmetatable(obj))
  s[obj] = res
  for k, v in pairs(obj) do res[copy(k, s)] = copy(v, s) end
  return res
end
local function equals(o1, o2, ignoreMt) -- Compare two variables (simple, tables, anything). Default ignore metatables.
  if ignoreMt == nil then ignoreMt = true end
  if o1 == o2 then return true end
  local o1Type = type(o1) local o2Type = type(o2)
  if o1Type ~= o2Type then return false end if o1Type ~= 'table' then return false end
  if not ignoreMt then local mt1 = getmetatable(o1) if mt1 and mt1.__eq then return o1 == o2 end end
  local keySet = {}
  for key1, value1 in pairs(o1) do local value2 = o2[key1] if value2 == nil or equals(value1, value2, ignoreMt) == false then return false end keySet[key1] = true end
  for key2, _ in pairs(o2) do if not keySet[key2] then return false end end
  return true
end
local function removeIrrelevant(keywords)
  local curr = {}
  for _, k in ipairs(keywords:split(',')) do
    local parts = k:split('=') if parts[2] ~= nil then parts[1] = parts[1]:trim()..'=' end
    if cudAll[parts[1]] then curr[#curr+1] = k end
  end
  return table.concat(curr, ',')
end
local function hex2float(raw)
  if tonumber(raw, 16) == 0 then return 0.0 end
  local raw = string.gsub(raw, "(..)", function (x) return string.char(tonumber(x, 16)) end)
  local byte1, byte2, byte3, byte4 = string.byte(raw, 1, 4)
  local sign = byte1 > 0x7F
  local exponent = (byte1 % 0x80) * 0x02 + math.floor(byte2 / 0x80)
  local mantissa = ((byte2 % 0x80) * 0x100 + byte3) * 0x100 + byte4
  if sign then sign = -1 else sign = 1 end
  local n if mantissa == 0 and exponent == 0 then n = sign * 0.0 elseif exponent == 0xFF then if mantissa == 0 then n = sign * math.huge else n = 0.0/0.0 end else n = sign * math.ldexp(1.0 + mantissa / 0x800000, exponent - 0x7F) end
  return n
end

local convertDatahex = { -- Convert a datahex value to the event type
  [dt.text]    = function (dh) return(string.gsub(dh, "(..)", function (x) return string.char(tonumber(x, 16)) end)) end, -- Convert string of hex to string of chars
  [dt.string]  = function (dh) return(string.gsub(dh, "(..)", function (x) return string.char(tonumber(x, 16)) end)) end,
  [dt.uint32]  = function (dh) return(tonumber(dh, 16)) end,
  [dt.uint16]  = function (dh) return(tonumber(dh, 16)) end,
  [dt.uint8]   = function (dh) return(tonumber(dh, 16)) end,
  [dt.int64]   = function (dh) return((tonumber(dh, 16) + 2^63) % 2^64 - 2^63) end, -- Convert to twos compliment signed
  [dt.int32]   = function (dh) return((tonumber(dh, 16) + 2^31) % 2^32 - 2^31) end,
  [dt.int16]   = function (dh) return((tonumber(dh, 16) + 2^15) % 2^16 - 2^15) end,
  [dt.int8]    = function (dh) return((tonumber(dh, 16) + 2^7) % 2^8 - 2^7) end,
  [dt.bool]    = function (dh) return(tonumber(dh, 16) == 1) end,
  [dt.float32] = function (dh) return(hex2float(string.sub(dh, 1, 8))) end, -- Only the first eight characters of datahex are needed (measurement and unit parameter add additional data)
  -- If LUA >= 5.3, would not need hex2float... Instead return(string.unpack('f', string.pack('i4', '0x'..string.sub(dh, 1, 8))))
  -- To consider, currently unsupported... dt.time, dt.date, dt.rgb/dt.uint24, dt.float16
}


--[[
Register with the Heartbeat script
--]]
local function isRegistered() local hbeat = storage.get('heartbeat', {}); local k; for k, _ in pairs(hbeat) do if k == _SCRIPTNAME then return true, hbeat end end return false, hbeat end
if sendHeartbeat > 0 then
  -- Check whether registration is required, and if not registered (or conditions changed) then register
  local r, hbeat = isRegistered()
  if not r or (r and not equals(hbeat[_SCRIPTNAME], heartbeatConditions)) then
    local k, v, vals
    vals = '' for k, v in pairs(heartbeatConditions) do vals = vals..k..'='..v..' ' end
    log('Registering '.._SCRIPTNAME..' with heartbeat of '..vals)
    hbeat[_SCRIPTNAME] = heartbeatConditions
    storage.set('heartbeat', hbeat)
  end
else -- Remove script from hearbeat registration
  local r, hbeat = isRegistered() if r then hbeat[_SCRIPTNAME] = nil storage.set('heartbeat', hbeat) end
end


--[[
Legacy event script management
--]]
local eventScripts = db:getall("SELECT name FROM scripting WHERE type = 'event'")
local eventName, finalName, acName, atName, s = nil, nil, nil, nil
for _, s in ipairs(eventScripts) do
  if s.name:lower() == 'mqtt' then eventName = s.name end
  if s.name:lower() == 'mqtt final' then finalName = s.name end
  if s.name:lower() == 'ac' then acName = s.name end
  if s.name:lower() == 'at' then atName = s.name end
end

local finalInstalled = finalName ~= nil and not (script.status(finalName) == nil or script.status(finalName) == false)
local eventInstalled = eventName ~= nil and not (script.status(eventName) == nil or script.status(eventName) == false)
local acInstalled = acName ~= nil and not (script.status(acName) == nil or script.status(acName) == false)
local atInstalled = atName ~= nil and not (script.status(atName) == nil or script.status(atName) == false)

if finalInstalled then script.disable(finalName) log('Disabling event script '..finalName..', as no longer required') end
if eventInstalled then script.disable(eventName) log('Disabling event script '..eventName..', as no longer required') end
if acInstalled then script.disable(acName) log('Disabling event script '..acName..', as no longer required') end
if atInstalled then script.disable(atName) log('Disabling event script '..atName..', as no longer required') end

local version = string.split(io.readfile('/lib/genohm-scada/version'):trim(), '.')


--[[
Mosquitto client and call-backs
--]]

local client = require('mosquitto').new(mqttClientId)
if mqttUsername then client:login_set(mqttUsername, mqttPassword) end
client:will_set(mqttCbus..'status', 'offline', mqttQoS, RETAIN) -- Last will and testament is to set status offline

client.ON_CONNECT = function(success)
  if success then
    log('Connected to Mosquitto broker')
    client:publish(mqttCbus..'status', 'online', mqttQoS, RETAIN)
    mqttStatus = 1
  end
end

client.ON_DISCONNECT = function(...)
  log('Mosquitto broker disconnected')
  mqttStatus = 2
  init = true
  reconnect = true
end

client.ON_MESSAGE = function(mid, topic, payload)
  if topic:contains(mqttDiscoveryTopic) then
    -- Record discovery topics to check for duplication
    local parts = string.split(topic, '/')
    if payload ~= '' then
      if parts[3] ~= nil and parts[3]:contains('cbus_mqtt_') then
        local j = json.decode(payload)
        local disc = string.split(parts[3], '_')
        local cnl
        if #disc == 6 then
          cnl = disc[6] disc[6] = nil disc = table.concat(disc, '_')
          if discovery[disc] == nil then
            discovery[disc] = { ['dtype']=parts[2], ['cnl']={ cnl, }, } -- Table of CBus addresses with type as the value, including a list of 'channels'
          else
            if #discovery[disc].cnl == 0
              then log('Warning: Existing duplicate discovery topics for '..disc..' ... '..parts[2]..' and '..discovery[disc].dtype..', so removing all')
              discoveryDelete[disc..'/'..parts[2]] = true
              discoveryDelete[disc..'_'..cnl..'/'..parts[2]] = true
            else
              discovery[disc].dtype = parts[2]
              discovery[disc].cnl[#discovery[disc].cnl+1] = cnl -- New 'channel' found
            end
          end
        else
          disc = parts[3]
          if discovery[disc] ~= nil and discovery[disc].dtype ~= parts[2] then
            log('Warning: Existing duplicate discovery topics for '..disc..' ... '..parts[2]..' and '..discovery[disc].dtype..', so removing all')
            discoveryDelete[disc..'/'..parts[2]] = true
            for _, cnl in ipairs(discovery[disc].cnl) do discoveryDelete[disc..'_'..cnl..'/'..discovery[disc].dtype] = true end
          else
            discovery[disc] = { ['dtype']=parts[2], ['cnl']={}, } -- Table of CBus addresses with type as the value
          end
        end
        discoveryName[disc] = j.dev.name -- Used for rename detection
        discoveryId[disc] = j.obj_id -- Used for ID change detection
      end
    end
  else
    mqttMessages[#mqttMessages + 1] = { topic=topic, payload=payload } -- Queue the message
  end
end


--[[
C-Bus events, only queues a C-Bus message at the end of a ramp
--]]
local function eventCallback(event)
  if mqttDevices[event.dst] then
    local value, ramp
    local parts = string.split(event.dst, '/')
    local tp = grp.find(event.dst).datatype
    
    if lighting[parts[2]] then
      value = tonumber(string.sub(event.datahex,1,2),16)
      local target = tonumber(string.sub(event.datahex,3,4),16)
      local ramp = tonumber(string.sub(event.datahex,5,8),16)
      if ramp > 0 then
        if event.meta == 'admin' then return end
        if value ~= target then return end
      end
    else
      if convertDatahex[tp] ~= nil then
        value = convertDatahex[tp](event.datahex)
      else
        log('Error: Unsupported data type '..dt..' for '..event.dst..', content of datahex '..event.datahex..', not setting')
        return
      end
    end
    if value == nil then log('Error: nil value for '..event.dst..', which should not happen, ignoring') return end
    if tp == dt.float32 then -- For floats don't set if this event is the same value. Compare to five decimal places, because these are an approximation
      local pre, comp
      if mqttDevices[event.dst].value ~= nil then pre = string.format('%.5f', mqttDevices[event.dst].value) else pre = nil end
      comp = string.format('%.5f', value)
      if comp == pre then
        if logging then log('Not setting '..event.dst..' to '..value..', same as previous value') end
        if logging then log('Content of datahex: '..event.datahex..'. Type='..grp.find(event.dst).datatype..'. pre='..pre..'. comp='..comp) end
        return
      end
    end
    if logging then log('Setting '..event.dst..' to '..tostring(value)..', previous='..tostring(mqttDevices[event.dst].value)) end
    mqttDevices[event.dst].value = value
    if type(value) == 'boolean' then value = value and 'ON' or 'OFF' end
    cbusMessages[#cbusMessages + 1] = { ['alias']=event.dst, ['net']=tonumber(parts[1]), ['app']=tonumber(parts[2]), ['group']=tonumber(parts[3]), ['value']=value, }
    if parts[4] ~= nil then cbusMessages[#cbusMessages].channel = tonumber(parts[4]) end

    -- Check whether to set the level as a tracked lastlevel
    local function setLastLevel(val)
      if val ~= 0 and val ~= lastLevel[event.dst] then
        lastLevel[event.dst] = val
        if logging then log('Set lastLevel to '..val..' for '..event.dst) end
        storage.set('lastlvl', lastLevel)
      end
    end

    if lighting[parts[2]] then
      if useLastLevel then
        setLastLevel(value)
      else
        if storeLevel ~= nil and storeLevel[event.dst] then setLastLevel(value) end
      end
    end
  elseif (panasonicSupport and ac[event.dst]) or (airtopiaSupport and at[event.dst]) then
    local parts = string.split(event.dst, '/')
    local value
    local tp = grp.find(event.dst).datatype
    if convertDatahex[tp] ~= nil then
      value = convertDatahex[tp](event.datahex)
    else
      log('Error: Unsupported data type '..dt..' for '..event.dst..', content of datahex '..event.datahex..', not setting')
      return
    end
    if logging then log('Setting '..event.dst..' to '..value) end
    cbusMessages[#cbusMessages + 1] = { ['alias']=event.dst, ['net']=tonumber(parts[1]), ['app']=tonumber(parts[2]), ['group']=tonumber(parts[3]), ['value']=value, }
  end
end

local localbus = require('localbus').new(busTimeout) -- Set up the localbus
localbus:sethandler('groupwrite', eventCallback)


--[[
Publish lighting, user parameter and trigger objects to MQTT 
--]]
local function publish(alias, app, level, noPre)
  if noPre == nil then noPre = false end
  if level == nil then log('Warning: Nil CBus level for '..alias); do return end end
  local state = ''
  if cover[alias] then
    if mqttDevices[alias].noleveltranslate then
      state = (tonumber(level) ~= 0) and 'open' or 'closed'
    else
      -- For CBus blind controllers report level unless it is 5, which is a preset for stop in level translation mode
      state = 'stopped'
      if level == 5 then level = -1 end
    end
  else
    if tonumber(level) ~= nil then
      state = (tonumber(level) ~= 0) and 'ON' or 'OFF'
    elseif type(level) == 'boolean' then
      level = level and 'ON' or 'OFF'
      state = level
    else
      state = level
    end
  end
  if not userParameter[alias] then
    if not binarySensor[alias] then
      if bSensor[alias] then -- It's a bSensor
        client:publish(mqttReadTopic..alias..'/level', level, mqttQoS, RETAIN)
        client:publish(mqttReadTopic..alias..'/state', state, mqttQoS, RETAIN)
        if logging then log('Publishing '..mqttReadTopic..alias..' to '..level) end
      elseif selects[alias] then -- It's a select
        local l
        for _, l in ipairs(selects[alias].allLvl) do
          if tonumber(level) <= l.lvl then
            if selectExact and tonumber(level) ~= l.lvl and app ~= 202 then
              -- Current CBus level does not match the select, so optionally adjust the CBus level
              if logging then log('Warning: Forcing level to set for select '..alias..' to nearest level '..l.lvl..' ('..tonumber(level)..' requested, but selectExact=true)') end
              grp.write(alias, l.lvl)
              --SetCBusLevel(net, app, group, l.lvl, 0)
              -- Adjusting the level will result in two MQTT publish events, which could be avoided but is not
            end
            client:publish(mqttReadTopic..alias..'/select', l.sel, mqttQoS, RETAIN)
            client:publish(mqttReadTopic..alias..'/level', l.lvl, mqttQoS, RETAIN)
            if logging then log('Publishing select '..mqttReadTopic..alias..' to '..l.sel..' ('..l.lvl..')') end
            break
          end
        end
      elseif button[alias] then -- It's a button, so do nothing as it has no state
      elseif cover[alias] then -- It's a cover, so vary state behaviour based on level translation mode
        if mqttDevices[alias].noleveltranslate then
          client:publish(mqttReadTopic..alias..'/state', state, mqttQoS, RETAIN)
          if level ~= -1 then client:publish(mqttReadTopic..alias..'/level', level, mqttQoS, RETAIN) end
          if logging then log('Publishing state and level '..mqttReadTopic..alias..' to '..state..'/'..level) end
        else
          local v
          if hasMembers(mqttDevices[alias].rate) then
            state = (coverLevel[alias] ~= 0) and 'open' or 'closed'
            v = coverLevel[alias]
          else
            state = (level ~= 0) and 'open' or 'closed'
            v = (level < 0) and 128 or level
          end
          client:publish(mqttReadTopic..alias..'/state', state, mqttQoS, RETAIN)
          client:publish(mqttReadTopic..alias..'/open', v, mqttQoS, RETAIN)
          if logging then log('Publishing state and open '..mqttReadTopic..alias..' to '..state..'/'..v) end
        end
      else -- It's a bog standard group
        local v
        client:publish(mqttReadTopic..alias..'/state', state, mqttQoS, RETAIN)
        if publishAdj[alias] then v = tonumber(string.format('%.'..publishAdj[alias].dec..'f', level * publishAdj[alias].scale)) else v = level end
        client:publish(mqttReadTopic..alias..'/level', v, mqttQoS, RETAIN)
        if logging then log('Publishing state and level '..mqttReadTopic..alias..' to '..state..'/'..v) end
      end
    else -- It's a binary sensor / trigger
      client:publish(mqttReadTopic..alias..'/state', state, mqttQoS, RETAIN)
      client:publish(mqttReadTopic..alias..'/level', level, mqttQoS, RETAIN)
      if logging then log('Publishing '..mqttReadTopic..alias..' to '..state..' ('..level..')') end
    end
  else -- It's a user parameter
    local v
    if publishAdj[alias] then v = tonumber(string.format('%.'..publishAdj[alias].dec..'f', level * publishAdj[alias].scale)) else v = level end
    client:publish(mqttReadTopic..alias..'/level', v, mqttQoS, RETAIN)
    if logging then log('Publishing '..mqttReadTopic..alias..' to '..v) end
  end
  if not noPre then
    if app ~= 202 then -- Not trigger
      local p = level
      if tonumber(level) ~= nil then p = string.format('%.3f', level) end
    end
  end
end


--[[
Tracking of cover transitions, estimating with time travelled
--]]
local function trackTransitions()
  local k, v
  local t = socket.gettime()
  local kill = {}
  
  for k, v in pairs(transition) do
    if t < v.ts then goto next end
    local closing = v.state == 'closing'
    local rate = closing and tonumber(mqttDevices[k].rate[2]) or tonumber(mqttDevices[k].rate[1])
    local increment = (t - v.ts) / rate * 256
    if closing then v.level = v.level - increment else v.level = v.level + increment end
    coverLevel[k] = math.floor(v.level + 0.5)
    v.ts = t
    if coverLevel[k] < 0 then coverLevel[k] = 0 elseif coverLevel[k] > 255 then coverLevel[k] = 255 end
    if (coverLevel[k] == 0 and closing) or (coverLevel[k] == 255 and not closing) then kill[k] = true end
    client:publish(mqttReadTopic..k..'/state', v.state, mqttQoS, RETAIN)
    client:publish(mqttReadTopic..k..'/open', coverLevel[k], mqttQoS, RETAIN)
    if logging then log('Publishing state and open '..mqttReadTopic..k..' to '..state..'/'..coverLevel[k]) end
    ::next::
  end
  if hasMembers(kill) then storage.set('coverLevel', coverLevel) end
  for k, _ in pairs(kill) do
    client:publish(mqttReadTopic..k..'/state', (coverLevel[k] ~= 0) and 'open' or 'closed', mqttQoS, RETAIN)
    transition[k] = nil
  end
end


--[[
Publish measurement application objects to MQTT 
--]]
local function publishMeasurement(alias, net, group, channel, value)
  if value == nil then log('Warning: Nil CBus measurement value for '..alias); do return end end
  local units, v
  local adjust = publishAdj[alias]
  if adjust then v = tonumber(string.format('%.'..adjust.dec..'f', value * adjust.scale)) else v = value end
  if includeUnits[alias] then
    _, units = GetCBusMeasurement(net, group, channel)
    if units == '$' then
      v = units..v
    elseif units == '%' then
      v = v..units
    else
      v = v..' '..units
    end
  end
  local mAlias = lastSlashToUnderscore(alias)
  client:publish(mqttReadTopic..mAlias..'/level', v, mqttQoS, RETAIN)
  if logging then log('Publishing measurement '..mqttReadTopic..mAlias..' to '..v) end
end


--[[
Publish unit parameter objects to MQTT 
--]]
local function publishUnitParam(alias, value)
  if value == nil then log('Warning: Nil unit parameter value for '..alias); do return end end
  local adjust = publishAdj[alias]
  local v
  if adjust then v = tonumber(string.format('%.'..adjust.dec..'f', value * adjust.scale)) else v = value end
  local mAlias = lastSlashToUnderscore(alias)
  client:publish(mqttReadTopic..mAlias..'/level', v, mqttQoS, RETAIN)
  if logging then log('Publishing unit parameter '..mqttReadTopic..mAlias..' to '..v) end
end


--[[
Publish Panasonic ESPHome objects to MQTT 
--]]
local function publishAc(alias, level, select)
  if level == nil then log('Warning: Nil AC level for '..alias); do return end end
  if ac[alias].state ~= level then
    if ignoreMqtt[alias] and (socket.gettime() - ignoreMqtt[alias] > ignoreTimeout) then -- Don't worry about older 'ignore' flags
      ignoreMqtt[alias] = nil
      if logging then log('Ignoring older MQTT ignore flag for '..alias) end
    end
    if not ignoreMqtt[alias] then
      local parts = string.split(ac[alias].name, '-')
      local topic = ''
      if select == 'func' then
        topic = parts[1]..'/climate/panasonic/'..parts[2]..'/command'
      elseif select == 'sel' then
        topic = parts[1]..'/select/'..parts[2]..'/command'
      elseif select == 'sense' then
        if logging then log('Warning: Not publishing sensor change for alias='..alias) end
      else
        log('Invalid AC command for alias='..alias..', select='..select)
      end
      if topic ~= '' then client:publish(topic, level, mqttQoS, NORETAIN) end
      ignoreCbus[alias] = socket.gettime(); if logging then log('Setting ignore CBus for '..alias) end
      if logging then log('Published AC '..ac[alias].name..' to '..level) end
    else
      ignoreMqtt[alias] = nil
      -- if logging then log('Intentionally ignoring MQTT publish for '..alias) end
    end
    ac[alias].state = level
  else
    ignoreMqtt[alias] = nil
    if logging then log('Ignoring MQTT publish for '..alias..' because already at level '..level) end
  end
end


--[[
Publish Airtopia MODBUS objects to MQTT 
--]]
local function publishAt(alias, level)
  if level == nil then log('Warning: Nil AT level for '..alias); do return end end
  if at[alias].state ~= level then
    if ignoreMqtt[alias] and (socket.gettime() - ignoreMqtt[alias] > ignoreTimeout) then -- Don't worry about older 'ignore' flags
      ignoreMqtt[alias] = nil
      if logging then log('Ignoring older MQTT ignore flag for '..alias) end
    end
    if not ignoreMqtt[alias] then
      local parts = string.split(at[alias].name, '-')
      local topic = 'airtopia/'..parts[1]..'/state/'..parts[2]
      local adjust = publishAdj[alias]
      if adjust then level = tonumber(string.format('%.'..adjust.dec..'f', level * adjust.scale)) end
      client:publish(topic, level, mqttQoS, RETAIN)
      if level ~= at[alias].state then ignoreCbus[alias] = socket.gettime(); if logging then log('Setting ignore CBus for '..alias) end end
      if logging then log('Published AT '..at[alias].name..' to '..level) end
      -- Determine whether a HomeAssistant state topic needs to be also published
      local st = nil
      local prefix = nil
      local dev = nil
      for k, v in pairs(atDevices) do
        if v == alias then prefix = string.split(k, '-')[1]; st = string.split(k, '-')[2]; break end
      end
      if st == nil then
      elseif st == 'horiz_swing' then
        -- Publish swingha
        local o = atDevices[prefix..'-vert_swing']
        if o ~= nil then
          parts = string.split(o, '/'); local net = tonumber(parts[1]); local group = tonumber(parts[3]); 
          local v = bit.lshift(GetUserParam(net, group), 1)
          local topic = 'airtopia/'..prefix..'/state/swingha'
          local s = bit.bor(tonumber(level), v) + 1
          client:publish(topic, atswings[s], mqttQoS, RETAIN)
        end
      elseif st == 'vert_swing' then
        -- Publish swingha
        local o = atDevices[prefix..'-horiz_swing']
        if o ~= nil then
          parts = string.split(o, '/'); local net = tonumber(parts[1]); local group = tonumber(parts[3]); 
          local h = GetUserParam(net, group)
          local topic = 'airtopia/'..prefix..'/state/swingha'
          local v = bit.lshift(tonumber(level), 1)
          local s = bit.bor(h, v) + 1
          client:publish(topic, atswings[s], mqttQoS, RETAIN)
        end
      elseif st == 'fan' then
        -- Publish fanha
        local fanv = atfans[level+1]
        local topic = 'airtopia/'..parts[1]..'/state/fanha'
        client:publish(topic, fanv, mqttQoS, RETAIN)
      end
    else
      ignoreMqtt[alias] = nil
      if logging then log('Intentionally ignoring MQTT publish for '..alias) end
    end
    at[alias].state = level
  else
    ignoreMqtt[alias] = nil
    if logging then log('Ignoring MQTT publish for '..alias..' because already at level '..level) end
  end
end


--[[
Get level name and value
--]]
local function decodeLevel(net, app, group, level, default)
  if level:contains('/') then log('Error: Legacy separator "/" being used for '..net..'/'..app..'/'..group..'! Use ":" instead') return nil, nil end
  local parts = string.split(level, ':')
  local lvl = -1
  if #parts == 2 then -- A select option and level
    lvl = tonumber(parts[2])
    if lvl == nil then log('Error: Invalid lvl= for '..net..'/'..app..'/'..group..', level "'..parts[2]..'" is probably not numeric') return nil, nil end
    if lvl < 0 or lvl > 255  then log('Error: Invalid lvl= for '..net..'/'..app..'/'..group..', level "'..parts[2]..'" is outside acceptable range') return nil, nil end
    return parts[1], lvl
  elseif #parts == 1 and tonumber(parts[1]) then -- Level numbers only
    lvl = tonumber(parts[1])
    if lvl < 0 or lvl > 255 then log('Error: Invalid lvl= for '..net..'/'..app..'/'..group..', level '..lvl..' is outside acceptable range') return nil, nil end
    parts[1] = GetCBusLevelTag(net, app, group, lvl)
    if parts[1] == nil then
      if default == nil then
        log('Error: No level tag for '..net..'/'..app..'/'..group..', level '..lvl..' which is required when specifying numeric only for lvl=') return nil, nil
      else
        parts[1] = default
        log('Warning: Trigger '..net..'/'..app..'/'..group..' has no level tag defined for level '..level..', setting to "'..default..'"')
      end
    end
    return parts[1], lvl
  elseif #parts == 1 then -- Level tags only
    lvl = GetCBusLevelAddress(net, app, group, parts[1])
    if lvl == nil then log('Error: Invalid lvl= for '..net..'/'..app..'/'..group..', level '..parts[1]) return nil end
    return parts[1], lvl
  end
end


--[[
Get key/value pairs. Returns a keyword if found in 'allow'. (allow, synonym and special parameters are optional).
--]]
local function getKeyValue(alias, tags, _L, synonym, special, allow)
  if synonym == nil then synonym = {} end
  if special == nil then special = {} end
  if allow == nil then allow = {} end
  local dType = nil
  for k, t in pairs(tags) do
    k = k:trim()
    if t ~= -1 then
      if special[k] ~= nil then special[k] = true end
      local v = t:trim()
      if _L[k] then
        if type(_L[k]) == 'number' then _L[k] = tonumber(v) if _L[k] == nil then error('Error: Bad numeric value for '..alias..', keyword "'..k..'="') end
        elseif type(_L[k]) == 'table' then
          _L[k] = string.split(v, '/')
          local i, tv for i, tv in ipairs(_L[k]) do _L[k][i] = tv:trim() end
        else _L[k] = v end
      end
    else
      if synonym[k] then k = synonym[k] end
      if special[k] ~= nil then special[k] = true end
      if allow[k] then
        if dType == nil then dType = k else error('Error: More than one "type" keyword used for '..alias) end
      end
    end
  end
  return dType
end


--[[
Build and publish a CBus MQTT discovery topic
--]]
local function addDiscover(net, app, group, channel, tags, name)
  -- Build an alias to refer to each group
  local alias = net..'/'..app..'/'..group
  if channel ~= nil then alias = alias..'/'..channel end

  if not name then -- Need a name from tag lookup for everything but measurement app
    if channel == nil then
      error('Error: nil channel for name '..tostring(name)..' at '..net..'/'..app..'/'..group..'... a name is required')
    else
      if app == 228 then name = 'Measurement '..alias else name = 'Unit parameter '..alias end
    end
  end

  -- All keywords except MQTT are optional (some exceptions), with 'light' as default discovery type. Defaults:
  local _L = {
    pn = name,      -- Preferred name
    sa = '',        -- Suggested area
    img = '',       -- Image
    unit = '',      -- Units
    class = '',     -- HomeAssistant class
    dec = 2,        -- Decimal places
    scale = 1,      -- Scale (multiplier or divider)
    on = 'On',      -- bsensor 'on' string
    off = 'Off',    -- bsensor 'off' string
    lvl = {},       -- Levels
    rate = {},      -- Rate of open/close for cover
    delay = 0,      -- Delay before starting cover tracking
    topic = '',     -- MQTT topic for inbound sensors
  }
  local synonym = { binarysensor = 'binary_sensor', fanpct = 'fan_pct' }
  local special = { includeunit = false, preset = false, dec = false, noleveltranslate = false, exactpn = false, }

  local lvl = false
  local dType, action, boid, dSa, payload, prefix, tag, k, t

  local function getEntity(entity)
    if _L.sa ~= '' then
      local startIdx, endIdx
      repeat
        startIdx, endIdx = entity:find(_L.sa, 1, true)
        if startIdx and startIdx == 1 then
          entity = entity:sub(endIdx + 1):match'^%s*(.*)'
        end 
      until not startIdx or startIdx > 1
    end
    return entity
  end

  local function addCommonPayload(payload, oid, entity, name, objId)
    -- Add payload common to all
    payload.name = json.null
    payload.obj_id = objId
    payload.uniq_id = oid
    payload.avty_t = mqttCbus..'status'
    payload.dev = { name=name, ids=_L.sa..' '..entity:trim(), sa=_L.sa, mf='Schneider Electric', mdl='CBus' }
    if _L.img ~= '' then payload.ic = _L.img end
    payload = json.encode(payload)
    return payload
  end

  local function removeOld(dType, oid)
    -- If dType has changed for an existing discovery topic then remove the previous topic(s)
    local disc = string.split(oid, '_')
    local cnl
    if #disc == 6 then
      cnl = disc[6] disc[6] = nil disc = table.concat(disc, '_')
      if discovery[disc] == nil then
        discovery[disc] = { ['dtype']=dType, ['cnl']={ cnl, }, } -- Table of CBus addresses with type as the value, including a list of 'channels'
      else
        if #discovery[disc].cnl == 0 then discoveryDelete[disc..'/'..discovery[disc].dtype] = true end
        discovery[disc].dtype = dType
        discovery[disc].cnl[#discovery[disc].cnl+1] = cnl -- New 'channel' found
      end
    else
      disc = oid
      if discovery[disc] ~= nil then
        if discovery[disc].dtype ~= dType then discoveryDelete[disc..'/'..discovery[disc].dtype] = true end
        for _, cnl in ipairs(discovery[disc].cnl) do discoveryDelete[disc..'_'..cnl..'/'..discovery[disc].dtype] = true end
      end
      discovery[disc] = { ['dtype']=dType, ['cnl']={}, } -- Table of CBus addresses with type as the value
    end
  end

  local function publish(payload, oid, entity, name, objId)
    -- Publish to MQTT broker
    if _L.sa == '' then dSa = 'no preferred area' else dSa = _L.sa end
    if logging then log('Publishing '..mqttDiscoveryTopic..dType..'/'..oid..'/config as '.._L.pn..' in area '..dSa) end
    if discoveryName[oid] ~= nil and discoveryName[oid] ~= name then client:publish(mqttDiscoveryTopic..dType..'/'..oid..'/config', '', mqttQoS, RETAIN) end -- Remove old discovery topic
    if forceChangeId then
      if discoveryId[oid] ~= nil and discoveryId[oid] ~= objId then client:publish(mqttDiscoveryTopic..dType..'/'..oid..'/config', '', mqttQoS, RETAIN) end -- Remove old discovery topic
    end
    client:publish(mqttDiscoveryTopic..dType..'/'..oid..'/config', payload, mqttQoS, RETAIN)
  end

  -- Build an OID (measurement application / unit parameter gets a channel as well), also add to mqttDevices
  local oid = 'cbus_mqtt_'..tNetCBus(net)..'_'.. app..'_'..group if channel ~= nil then oid = oid..'_'..channel end
  mqttDevices[alias].oid = oid
  mqttDevices[alias].net = net
  mqttDevices[alias].app = app
  mqttDevices[alias].group = group
  if channel then mqttDevices[alias].channel = channel end

  -- Clear any previous lookup table entries
  cover[alias] = nil
  fan[alias] = nil
  bSensor[alias] = nil
  binarySensor[alias] = nil
  button[alias] = nil
  local oldLightingButton = lightingButton[alias] lightingButton[alias] = nil
  userParameter[alias] = nil
  unitParameter[alias] = nil
  storeLevel[alias] = nil
  for s, _ in pairs(special) do mqttDevices[s] = nil end

  local allow = {
    light = {
      getPayload = function()
        return {stat_t = mqttReadTopic..alias..'/state', cmd_t = mqttWriteTopic..alias..'/switch', bri_stat_t = mqttReadTopic..alias..'/level', bri_cmd_t = mqttWriteTopic..alias..'/ramp', pl_off = 'OFF', on_cmd_type = 'brightness',}
      end
    },
    switch = {
      getPayload = function()
        return {stat_t = mqttReadTopic..alias..'/state', cmd_t = mqttWriteTopic..alias..'/switch', pl_on = 'ON', pl_off = 'OFF',}
      end
    },
    cover = {
      getPayload = function()
        cover[alias] = true
        if _L.rate[2] == nil then _L.rate[2] = _L.rate[1] end
        mqttDevices[alias].rate = _L.rate
        mqttDevices[alias].delay = _L.delay
        if special.noleveltranslate then
          mqttDevices[alias].noleveltranslate = true
          return {stat_t = mqttReadTopic..alias..'/state', cmd_t = mqttWriteTopic..alias..'/ramp', pos_open = 255, pos_clsd = 0, pl_open = 'OPEN', pl_cls = 'CLOSE', pos_t = mqttReadTopic..alias..'/level', set_pos_t = mqttWriteTopic..alias..'/ramp',}
        else
          mqttDevices[alias].noleveltranslate = false
          if not hasMembers(_L.rate) then log('Warning: No cover open/cose rate specified for '..alias..'. Transition tracking disabled.') end
          if coverLevel[alias] == nil then coverLevel[alias] = grp.getvalue(alias) log('Warning: Initialising cover level for '..alias..' with '..grp.getvalue(alias)..'. This may not be correct.') end
          return {stat_t = mqttReadTopic..alias..'/state', cmd_t = mqttWriteTopic..alias..'/ramp', pos_open = 255, pos_clsd = 0, pl_open = 'OPEN', pl_cls = 'CLOSE', pos_t = mqttReadTopic..alias..'/open', set_pos_t = mqttWriteTopic..alias..'/ramp',}
        end
      end
    },
    fan = {
      getPayload = function()
        fan[alias] = true
        storeLevel[alias] = true return {
          pl_on = 'ON', pl_off = 'OFF',
          stat_t = mqttReadTopic..alias..'/state', cmd_t = mqttWriteTopic..alias..'/ramp',
          pr_modes = {'off', 'low', 'medium', 'high'},
          pr_mode_cmd_t = mqttWriteTopic..alias..'/ramp', pr_mode_cmd_tpl = '{% if value == "off" %} 0 {% elif value == "low" %} 86 {% elif value == "medium" %} 170 {% elif value == "high" %} 255 {% endif %}',
          pr_mode_stat_t = mqttReadTopic..alias..'/level', pr_mode_val_tpl = '{% if value | int == 0 %} off {% elif value | int == 86 %} low {% elif value | int == 170 %} medium {% elif value | int == 255 %} high {% endif %}',
        }
      end
    },
    fan_pct = {
      getPayload = function()
        dType = 'fan' fan[alias] = true storeLevel[alias] = true
        local payload = {
          pl_on = 'ON', pl_off = 'OFF',
          stat_t = mqttReadTopic..alias..'/state', cmd_t = mqttWriteTopic..alias..'/ramp',
          pct_cmd_t = mqttWriteTopic..alias..'/ramp', pct_cmd_tpl = '{% if value | int == 0 %} 0 {% elif value | int == 1 %} 86 {% elif value | int == 2 %} 170 {% elif value | int == 3 %} 255 {% endif %}',
          pct_stat_t = mqttReadTopic..alias..'/level', pct_val_tpl = '{% if value | int == 0 %} 0 {% elif value | int == 86 %} 1 {% elif value | int == 170 %} 2 {% elif value | int == 255 %} 3 {% endif %}',
          spd_rng_min = 1,
          spd_rng_max = 3,
          opt = false,
        }
        if special.preset then
          payload.pr_modes = {'off', 'low', 'medium', 'high'}
          payload.pr_mode_cmd_t = mqttWriteTopic..alias..'/ramp'
          payload.pr_mode_cmd_tpl = '{% if value == "off" %} 0 {% elif value == "low" %} 86 {% elif value == "medium" %} 170 {% elif value == "high" %} 255 {% endif %}'
          payload.pr_mode_stat_t = mqttReadTopic..alias..'/level'
          payload.pr_mode_val_tpl = '{% if value | int == 0 %} off {% elif value | int == 86 %} low {% elif value | int == 170 %} medium {% elif value | int == 255 %} high {% endif %}'
        end
        return payload
      end
    },
    sensor = {
      getPayload = function()
        local payload
        local str = false
        if channel ~= nil then payload = { stat_t = mqttReadTopic..net..'/'..app..'/'..group..'_'..channel..'/level', } else payload = { stat_t = mqttReadTopic..alias..'/level', } end
        if lighting[tostring(app)] and not special.dec then _L.dec = 0 end
        if _L.class ~= '' then payload.dev_cla = _L.class end
        if app == 250 then userParameter[alias] = true end
        if app == 255 then unitParameter[alias] = true end
        if #_L.lvl == 0 then
          if app == 250 then _, _ = pcall(function () if tonumber(GetUserParam(net, group)) ~= nil then payload.val_tpl = '{{ value | float | round ('.._L.dec..') }}' end end)
          else payload.val_tpl = '{{ value | float | round ('.._L.dec..') }}'
          end
          if not payload.val_tpl then str = true end
        else
          str = true
          local count = 0
          local tpl
          for _, level in ipairs(_L.lvl) do
            local tag, lvl = decodeLevel(net, app, group, level)
            if tag ~= nil then
              if count == 0 then tpl = '{% if value | float == '..lvl..' %}'..tag else tpl = tpl..'{% elif value | float == '..lvl..' %}'..tag end
              count = count + 1
            else
              return nil
            end
          end
          payload.val_tpl = tpl..'{% else %}Unknown{% endif %}'
        end
        if _L.dec ~= 2 or _L.scale ~= 1 then publishAdj[alias] = { dec = _L.dec, scale = _L.scale } end -- Scale, decimals and units only for sensors
        if _L.unit ~= '' and not special.includeUnit then payload.unit_of_meas = _L.unit else if not str then payload.unit_of_meas = '' end end
        return payload
      end
    },
    binary_sensor = {
      getPayload = function()
        binarySensor[alias] = true
        return {stat_t = mqttReadTopic..alias..'/state', pl_on = 'ON', pl_off = 'OFF',}
      end
    },
    bsensor = {
      getPayload = function()
        bSensor[alias] = true dType = 'sensor'
        return {stat_t = mqttReadTopic..alias..'/level', val_tpl = '{% if value | float == 0 %} '.._L.off..' {% else %} '.._L.on..' {% endif %}',}
      end
    },
    isensor = {
      getPayload = function()
        if _L.topic == '' then log('Error: topic= keyword not specified for isensor at '..alias..', which is required') return nil end
        return 'inbound'
      end
    },
    button = {
      getPayload = function()
        button[alias] = true
        if lighting[tostring(app)] then
          lightingButton[alias] = true
          return {cmd_t = mqttWriteTopic..alias..'/press',}
        elseif app == 202 then
          local i
          mqttDevices[alias].trigger = {}
          mqttDevices[alias].type = 'button'
          if #_L.lvl == 0 then for i = 0,255 do _L.lvl[#_L.lvl + 1] = i end end -- If no "lvl=" specified then scan all levels, which is most inefficient!
          for _, i in ipairs(_L.lvl) do
            local tag, lvl = decodeLevel(net, app, group, i, publishNoLevel and 'Level '..i or nil)
            if tag then
              boid = oid..'_'..lvl
              table.insert(mqttDevices[alias].trigger, boid)
              action = tag:gsub("%s+", "_"):lower() -- Replace spaces with underscores
              if triggers[group] == nil then triggers[group] = {} end
              triggers[group][action] = lvl
              if _L.pn == name then prefix = '' else prefix = _L.pn..' ' end
              local entity = getEntity(prefix..tag)
              local name
              if special.exactpn or not removeSaFromStartOfPn then name = prefix..tag else name = entity end
              local objId if not entityIdAsIndentifier then objId = boid else objId = (_L.sa..' '..entity:trim()):lower():gsub('[%p%c]',''):gsub(' ','_'):gsub('__','_'):gsub('__','_') end
              payload = addCommonPayload({ cmd_t = mqttWriteTopic..alias..'/'..action..'/press', }, boid, entity, name, objId)
              removeOld(dType, boid)
              publish(payload, boid, entity, name, objId)
            end
          end
          return 'buttons'
        else
          log('Warning: MQTT button keyword used for unsupported application group '..alias)
          return nil
        end
      end
    },
    select = {
      getPayload = function()
        if #_L.lvl == 0 then log('Error: lvl= keyword not specified for select at '..alias..', which is required') return nil end
        local level
        local options = {}
        selects[alias] = {}
        for _ , level in ipairs(_L.lvl) do
          local opt, sel = decodeLevel(net, app, group, level)
          if opt ~= nil then
            options[#options + 1] = opt
            selects[alias][opt] = sel
            if not selects[alias].allLvl then selects[alias].allLvl = {} end; selects[alias].allLvl[#selects[alias].allLvl + 1] = { lvl = sel, sel = opt }
          else
            return nil
          end
        end
        table.sort(selects[alias].allLvl, function (left, right) return left.lvl < right.lvl end)
        return {stat_t = mqttReadTopic..alias..'/select', cmd_t = mqttWriteTopic..alias..'/select', options = options,}
      end
    },
  }

  -- Extract MQTT topic settings
  dType = getKeyValue(alias, tags, _L, synonym, special, allow)
  if dType == nil then dType = 'light' end -- Use light as default HomeAssistant type if not specified
  
  -- Default images
  if _L.img == '' then
    local pnl = _L.pn:lower()
    for k, v in pairs(imgDefault) do
      if pnl:contains(k) then
        if type(v) == 'string' then _L.img = v
        else
          local ik, iv, theElse
          for ik, iv in pairs(v) do if ik ~= '#else' then if pnl:contains(ik) then _L.img = iv end else theElse = v['#else'] end end
          if _L.img == '' then _L.img = theElse end
        end
      end
    end
    if _L.img == '' then
      if lighting[tostring(app)] then
        _L.img = 'mdi:lightbulb' -- Lighting default
      elseif app == '228' or app == '250' or app == '255' then
        _L.img = 'mdi:eye' -- Measurement and user/unit parameter default
      end
    end
  end

  if dType == 'light' and app == 228 then dType = 'sensor'; log('Warning: publishing measurement app '..alias..' as a sensor, not light') end -- Measurement app sensor with incorrect/missing type
  if special.includeUnit then includeUnits[alias] = true if logging then log('Including units for '..alias) end else includeUnits[alias] = nil end

  payload = allow[dType].getPayload()

  local entity = getEntity(_L.pn)
  local objId if not entityIdAsIndentifier then objId = oid else objId = (_L.sa..' '..entity:trim()):lower():gsub('[%p%c]',''):gsub(' ','_'):gsub('__','_'):gsub('__','_') end

  if payload ~= nil and payload ~= 'buttons' and payload ~= 'inbound' then -- If payload received then publish
    mqttDevices[alias].type = dType
    local name
    if special.exactpn or not removeSaFromStartOfPn then name = _L.pn else name = entity end
    payload = addCommonPayload(payload, oid, entity, name, objId)
    removeOld(dType, oid)
    publish(payload, oid, entity, name, objId)
    mqttDevices[alias].value = grp.getvalue(alias)
    if not oldLightingButton and lightingButton[alias] then -- If changing to a lighting button then clear status topics
      local t = mqttReadTopic..alias..'/state'
      if mqttJunk then client:publish(t, 'junk', mqttQoS, RETAIN) end client:publish(t, '', mqttQoS, RETAIN)
      t = mqttReadTopic..alias..'/level'
      if mqttJunk then client:publish(t, 'junk', mqttQoS, RETAIN) end client:publish(t, '', mqttQoS, RETAIN)
    end
    return
  elseif payload == 'buttons' then
    -- Trigger app buttons have already been published, so do nothing
  elseif payload == 'inbound' then
    -- Inbound sensor, so no discovery, just set up to receive the sensor and subscribe to the topic
    inbound[_L.topic] = { alias=alias, }
    client:subscribe(_L.topic, mqttQoS)
  else
    mqttDevices[alias] = nil
    error('Warning: a publish payload for '..name..' could not be built, so not published')
  end
end


--[[
Build and publish an Airtopia discovery topic
--]]
local function addAtDiscover(name, sa, unit)
  local dSa, payload

  if sa == '' then dSa = 'no preferred area' else dSa = sa end
  if logging then log('Publish discovery '..name..' in area '..dSa) end

  -- Build an OID and name prefix
  local sao = ''; if sa ~= '' then sao = string.lower(sa:gsub("% ", "_"))..'_' end
  local oid = 'cbus_mqtt_'..sao..string.lower(name:gsub("% ", "_"))

  payload = {
    name = '',
    obj_id = oid,
    uniq_id = oid,
    avty_t = mqttCbus..'status',
    dev = { name=name, ids=sa..' '..name, sa=sa, mf='Schneider Electric', mdl='Airtopia' },
    mode_cmd_t = 'airtopia/'..sao..name..'/cmd/mode',
    mode_stat_t = 'airtopia/'..sao..name..'/state/modeha',
    pow_cmd_t = 'airtopia/'..sao..name..'/cmd/power',
    temp_cmd_t = 'airtopia/'..sao..name..'/cmd/target_temperature',
    temp_stat_t = 'airtopia/'..sao..name..'/state/target_temperature',
    curr_temp_t = 'airtopia/'..sao..name..'/state/current_temperature',
    swing_modes = atswings,
    swing_mode_cmd_t = 'airtopia/'..sao..name..'/cmd/swing',
    swing_mode_stat_t = 'airtopia/'..sao..name..'/state/swingha',
    fan_modes = atfans,
    fan_mode_cmd_t = 'airtopia/'..sao..name..'/cmd/fan',
    fan_mode_stat_t = 'airtopia/'..sao..name..'/state/fanha',
    temp_unit = "C",
    opt = false,
    pl_on = 'ON',
    pl_off = 'OFF',
    precision = 1.0,
  }

  -- Publish to MQTT broker
  local j = json.encode(payload)
  if logging then log('Publishing '..mqttDiscoveryTopic..'climate/'..oid..'/config') end
  client:publish(mqttDiscoveryTopic..'climate/'..oid..'/config', j, mqttQoS, RETAIN)

  -- Add a power consumption sensor discovery topic
  if unit == nil then unit = 'A' end
  payload = {
    name = '',
    obj_id = oid..'_power',
    uniq_id = oid..'_power',
    avty_t = mqttCbus..'status',
    dev = { name=name..' Power Consumption', ids=sa..' '..name..' Power Consumption', sa=sa, mf='Schneider Electric', mdl='Airtopia' },
    stat_t = 'airtopia/'..sao..name..'/state/power_consumption',
    unit_of_meas = unit,
  }
  local j = json.encode(payload)
  if logging then log('Publishing'..mqttDiscoveryTopic..'sensor/'..oid..'_power'..'/config') end
  client:publish(mqttDiscoveryTopic..'sensor/'..oid..'_power'..'/config', j, mqttQoS, RETAIN)
end


--[[
Add Airtopia objects 
--]]
local atLog = {}
local atLogGrp = {}
local function addAt(grps, found)
  local atArea = {}
  local atDevs = {}
  local alias, k, v
  local addition = false
  local scan = {}
  local found = {}
  local stat, err

  for alias, v in pairs(grps) do
    local _L = { sa = '', dev = '', func = '', sense = '', unit = 'A', scale = 1, decimals = 2, }
    getKeyValue(alias, v.tags, _L)
    if _L.dev ~= '' then atDevs[_L.dev] = true end
    if atArea[_L.dev] == nil and _L.sa ~= '' then
      atArea[_L.dev] = _L.sa  -- The suggested area found is noted as being applicable for all user params of the device; only one needs be tagged
      atLog[_L.dev] = nil
    end

    if _L.sense ~= '' then
      if _L.scale ~= 1 or _L.decimals ~= 2 then publishAdj[alias] = { dec=_L.decimals, scale=_L.scale } end
    end
    scan[alias] = { dev=_L.dev, func=_L.func, sense=_L.sense, unit=_L.unit, net=v.net, app=v.app, group=v.group }
  end

  for alias, v in pairs(scan) do
    if v.dev ~= '' then
      if atLog[v.dev] == nil and atArea[v.dev] == nil then
        log('Error: No suggested area set for Airtopia device '..v.dev..'. At least one user parameter needs "sa="')
        atLog[v.dev] = true -- Logged for the device, so do not log any further related user param issues for the device
        goto nextAt
      end
      if at[alias] == nil and atArea[v.dev] ~= nil then
        local sa = atArea[v.dev]; if sa == nil then sa = '' end
        local sao = ''; if sa ~= '' then sao = string.lower(sa:gsub("% ", "_"))..'_' end
        if v.func ~= '' then
          if not at[alias] then
            at[alias] = {}; addition = true
            at[alias].name = sao..v.dev..'-'..v.func; at[alias].select = 'func'; atDevices[sao..v.dev..'-'..v.func] = alias;
            if atBoards[sao..v.dev] == nil and v.func == 'power' then atBoards[sao..v.dev] = {alias=alias, dev=v.dev, sa=sa} end
            stat, err = pcall(publishAt, alias, GetUserParam(v.net, v.group)) if not stat then log(err) end
            atLog[v.dev] = nil
            atLogGrp[alias] = nil
          end
        elseif sense ~= '' then
          if not at[alias] then
            if atBoards[sao..v.dev] ~= nil then
              at[alias] = {}; addition = true
              at[alias].name = sao..v.dev..'-'..v.sense; at[alias].select = 'sense'; at[alias].sense = v.sense; atDevices[sao..v.dev..'-'..v.sense] = alias
              atBoards[sao..v.dev].unit = v.unit
              stat, err = pcall(publishAt, alias, GetUserParam(v.net, v.group)) if not stat then log(err) end
              atLog[v.dev] = nil
              atLogGrp[alias] = nil
            end
          end
        end
      end
    else
      if not atLogGrp[alias] then log('Error: No device specified for Airtopia group '..alias); atLogGrp[alias] = true end
    end
    ::nextAt::
    if at[alias] ~= nil and atArea[v.dev] ~= nil then
      found[alias] = true -- Valid, having a sa=, so found (otherwise removed elsewhere if an existing device)
    end
  end
  return addition, found
end


--[[
Get applicable groups and keywords
--]]
local function getGroups(kw)
  local t
  local grps = {}
  for _, t in ipairs(db:getall("SELECT o.address, o.tagcache, o.name FROM objects AS o JOIN objecttags AS ot ON o.id=ot.object WHERE ot.tag='"..kw.."'")) do
    if t.tagcache == nil then goto skip end
    local alias = knxlib.decodega(t.address)
    local parts = load("return {"..alias:gsub('/',',').."}")()
    grps[alias] = { tags = {}, name = t.name, keywords = t.tagcache:gsub(', ',','), net = parts[1], app = parts[2], group = parts[3], channel = parts[4], }
    if parts[2] == 228 then -- Get the measurement app channel name from the CBus tag map
      local resp = db:getall('SELECT tag FROM cbus_tag_map WHERE tagtype="S" AND net='..parts[1]..' AND app='..parts[2]..' AND grp='..parts[3]..' AND tagid='..parts[4])
      if resp ~= nil and resp[1] ~= nil and resp[1]['tag'] ~= nil then grps[alias].name = resp[1]['tag'] else grps[alias].name = alias end
    end
    local tags = {}
    local tg
    for _, tg in ipairs(grps[alias].keywords:split(',')) do
      parts = tg:split('=')
      if parts[2] then tags[parts[1]:trim()] = parts[2]:trim() else tags[parts[1]:trim()] = -1 end
    end
    grps[alias].tags = tags
    ::skip::
  end
  return grps
end


--[[
Queue up initial discovery and current state CBus objects, plus Airtopia if used
--]]
local function publishCurrent()
  -- CBus
  mqttDevices = {}
  local grps = getGroups('MQTT')
  local n = 0
  local i, k, v, alias, name
  for alias, v in pairs(grps) do
    n = n + 1
    if v.name then name = v.name else
      if v.app ~= 228 then
        name = GetCBusGroupTag(v.net, v.app, v.group)
      else
        name = nil
      end
    end
    unpublished[n] = {net=v.net, app=v.app, group=v.group, channel=v.channel, tags=v.tags, name=name}
    if not mqttDevices[alias] then mqttDevices[alias] = {}; mqttDevices[alias].tags = v.tags; mqttDevices[alias].keywords = removeIrrelevant(v.keywords) end
  end
  if n > 0 then if logging then log('Queued '..n..' objects with keyword MQTT for publication') end end

  if airtopiaSupport then
    atDevices = {}
    grps = getGroups('AT')
    addAt(grps)
    local raw = {}
    local dev
    for alias, v in pairs(grps) do
      dev = ''; local sa = nil; local vv
      for tag, vv in pairs(v.tags) do
        if tag == 'dev' then
          dev = vv
        elseif tag == 'sa' then
          sa = vv
        end
      end
      if dev ~= '' then
        if sa ~= nil then raw[dev] = sa end
      else
        if not atLogGrp[alias] then
          log('Error: No device specified for Airtopia group '..alias)
          atLogGrp[alias] = true
        end
      end
    end
    n = 0
    for k, v in pairs(raw) do
      n = n + 1
      unpublishedAt[n] = {name=k, sa=v}
    end
    if n > 0 then if logging then log('Queued '..n..' objects with keyword AT for publication') end end
  end
end


--[[
Create / update / delete AC devices
--]]
local acLogGrp = {}
local function cudAc()
  local nClock = socket.gettime()
  local grps = getGroups('AC')
  local found = {}
  local addition = false
  local count = 0
  local alias, k, v, kill

  for alias, v in pairs(grps) do
    found[alias] = true

    local _L = { dev = '', func = '', sel = '', sense = '', topic = 'sensor', }
    getKeyValue(alias, v.tags, _L)

    if _L.dev ~= '' then
      if _L.func ~= '' then
        if not ac[alias] then ac[alias] = {} addition = true count = count + 1 end
      	ac[alias].name = _L.dev..'-'.._L.func; ac[alias].select = 'func'; acDevices[_L.dev..'-'.._L.func] = alias; acBoards[_L.dev] = true
      elseif _L.sel ~= '' then
        if not ac[alias] then ac[alias] = {} addition = true count = count + 1 end
      	ac[alias].name = _L.dev..'-'.._L.sel; ac[alias].select = 'sel'; acDevices[_L.dev..'-'.._L.sel] = alias; acBoards[_L.dev] = true
      elseif _L.sense ~= '' then
        if not ac[alias] then ac[alias] = {} addition = true count = count + 1 end
      	ac[alias].name = _L.dev..'-'.._L.sense; ac[alias].select = 'sense'; ac[alias].sense = _L.sense; ac[alias].topic = _L.topic; acDevices[_L.dev..'-'.._L.sense..'-sense'] = alias; acBoards[_L.dev] = true; acSense[_L.dev..'-'.._L.sense] = alias
      end
      ac[alias].net = v.net
      ac[alias].group = v.group
      acLogGrp[alias] = nil
    else
      if not acLogGrp[alias] then log('Error: No device specified for Panasonic '..alias); acLogGrp[alias] = true end
    end
  end

  -- Handle deletions
  local removed = 0
  for k, _ in pairs(ac) do
    if not found[k] then
      local name if ac[k].select == 'sense' then name = ac[k].name..'-sense' else name = ac[k].name end
      log('Removing '..k..' AC '..name) kill = name; ac[k] = nil; acDevices[kill] = nil removed = removed + 1
    end
  end
  if removed > 0 then
    log('Removed '..removed..' Panasonic A/C object'..(removed ~= 1 and 's' or '')..(logms and ' in '..string.format('%.3f', socket.gettime()-nClock)..' seconds' or ''))
  end
  -- Handle additions, and re-subscribe all board topics to get status of newly added devices
  if addition then
    for k, _ in pairs(acBoards) do client:subscribe(k..'/#', 2) end
    log('Added '..count..' Panasonic A/C object'..(count ~= 1 and 's' or '')..(logms and ' in '..string.format('%.3f', socket.gettime()-nClock)..' seconds' or ''))
  end
end


--[[
Publish the state of Airtopia devices
--]]
local function publishAtState()
  local k
  for k, _ in pairs(atBoards) do
    local parts, topic, level
    local mode = atDevices[k..'-mode']
    local power = atDevices[k..'-power']
    if mode ~= nil and power ~= nil then
      parts = string.split(mode, '/'); local mnet = tonumber(parts[1]); local mgroup = tonumber(parts[3])
      parts = string.split(power, '/'); local pnet = tonumber(parts[1]); local pgroup = tonumber(parts[3])
      topic = 'airtopia/'..k..'/state/modeha'
      if GetUserParam(pnet, pgroup) == 0 then
        level = 'off'
      else
        level = atmodes[GetUserParam(mnet, mgroup)]
      end
      client:publish(topic, level, mqttQoS, RETAIN)
    end
    local hswing = atDevices[k..'-horiz_swing']
    local vswing = atDevices[k..'-vert_swing']
    if hswing ~= nil and vswing ~= nil then
      parts = string.split(hswing, '/'); local hnet = tonumber(parts[1]); local hgroup = tonumber(parts[3])
      parts = string.split(vswing, '/'); local vnet = tonumber(parts[1]); local vgroup = tonumber(parts[3])
      topic = 'airtopia/'..k..'/state/swingha'
      local h = GetUserParam(hnet, hgroup)
      local v = bit.lshift(GetUserParam(vnet, vgroup), 1)
      local s = bit.bor(h, v) + 1
      client:publish(topic, atswings[s], mqttQoS, RETAIN)
    end
    local fan = atDevices[k..'-fan']
    if fan ~= nil then
      parts = string.split(fan, '/'); local fnet = tonumber(parts[1]); local fgroup = tonumber(parts[3])
      topic = 'airtopia/'..k..'/state/fanha'
      local f = GetUserParam(fnet, fgroup)
      client:publish(topic, atfans[f+1], mqttQoS, RETAIN)
    end
    client:subscribe('airtopia/'..k..'/#', 2)
  end
end


--[[
Create / update / delete Airtopia devices
--]]
local function cudAt()
  local grps = getGroups('AT')
  local boards = copy(atBoards)
  local k, v, topic, kill
  unpublishedAt = {}

  local addition, found = addAt(grps)

  -- Handle deletions
  for k, _ in pairs(at) do
    if not found[k] then kill = at[k].name; at[k] = nil; atDevices[kill] = nil end
  end
  local newBoards = {}
  for k, _ in pairs(atDevices) do
    local parts = string.split(k, '-')
    newBoards[parts[1]] = true
  end
  kill = {} for k, _ in pairs(atBoards) do if newBoards[k] == nil then kill[#kill + 1] = k end end
  for _, k in ipairs(kill) do
    atBoards[k] = nil;
    -- Clean up discovery topics
    topic = mqttDiscoveryTopic..'climate/'..'cbus_mqtt_'..k..'/config'; client:publish(topic, '', mqttQoS, RETAIN) log('Removed discovery topic '..topic)
    topic = mqttDiscoveryTopic..'sensor/'..'cbus_mqtt_'..k..'_power/config'; client:publish(topic, '', mqttQoS, RETAIN) log('Removed discovery topic '..topic)
    -- Clean up state and cmd topics under airtopia/device
    for _, v in ipairs(airtopiaStates) do client:publish('airtopia/'..k..'/state/'..v, '', mqttQoS, RETAIN) end
    for _, v in ipairs(airtopiaCmds) do client:publish('airtopia/'..k..'/cmd/'..v, '', mqttQoS, RETAIN) end
    log('Removed device command and state topics')
  end

  -- Handle additions
  local n = 0
  for k, v in pairs(atBoards) do
    if boards[k] == nil then
      if v.sa ~= nil then
        n = n + 1
        unpublishedAt[n] = {name=v.dev, sa=v.sa, unit=v.unit}
        addition = true
      else
        log('Error publishing Airtopia '..k..'. No suggested area given')
      end
    end
  end

  if addition then log('AT object keywords added') end
end


--[[
Create / update / delete ENV (environment) devices
--]]
local envLogGrp = {}
local function cudEnv()
  local nClock = socket.gettime()
  local grps = getGroups('ENV')
  local found = {}
  local addition = false
  local count = 0
  local alias, k, v, kill

  for alias, v in pairs(grps) do
    found[alias] = true

    local _L = { dev = '', func = '', }
    getKeyValue(alias, v.tags, _L)

    if _L.dev ~= '' then
      if _L.func == '' then
        local n
        if v.name then n = v.name else n = GetCBusGroupTag(v.net, v.app, v.group) end
        _L.func = n:lower():gsub("%s+", "_")
      end
      if not env[alias] then env[alias] = {}; addition = true count = count + 1 end
      env[alias].name = _L.dev..'-'.._L.func; envDevices[_L.dev..'-'.._L.func] = {v.net, v.group, alias}; envBoards[_L.dev] = true
      envLogGrp[alias] = nil
    else
      if not envLogGrp[alias] then log('Error: No device specified for environment sensor '..alias); envLogGrp[alias] = true end
    end
  end

  -- Handle deletions
  local removed = 0
  for k, _ in pairs(env) do
    if not found[k] then kill = env[k].name; env[k] = nil; envDevices[kill] = nil; removed = removed + 1 end
  end
  if removed > 0 then
    log('Removed '..removed..' environment sensor object'..(removed ~= 1 and 's' or '')..(logms and ' in '..string.format('%.3f', socket.gettime()-nClock)..' seconds' or ''))
  end
  -- Handle additions, and re-subscribe all board topics to get status of newly added devices
  if addition then
    for k, _ in pairs(envBoards) do client:subscribe(k..'/#', 2) end
    log('Added '..count..' environment sensor object'..(count ~= 1 and 's' or '')..(logms and ' in '..string.format('%.3f', socket.gettime()-nClock)..' seconds' or ''))
  end
end


--[[
Create / update / delete CBus MQTT discovery topics
--]]
local function cudCBusTopics()
  local function difference(a, b)
    local aa = {}; for _, v in ipairs(a) do aa[v] = true end; for _, v in ipairs(b) do aa[v] = nil end
    local ret = {}; for _, v in ipairs(a) do if aa[v] then ret[#ret+1]=v end end
    return ret
  end

  unpublished = {}
  local nClock = socket.gettime()
  local grps = getGroups('MQTT')
  local found, lvlDelete, queued = {}, {}, {}
  local n = 0
  local k, v, alias, lvl, olvl, name

  for alias, v in pairs(grps) do
    local change = false

    found[alias] = true
    local curr = removeIrrelevant(v.keywords)

    if not mqttDevices[alias] then -- New group
      change = true
      mqttDevices[alias] = {}
      mqttDevices[alias].keywords = curr
    else
      if mqttDevices[alias].keywords ~= curr then -- Modified group
        if v.app == 202 then
          lvl = nil
          if v.tags.lvl then
            lvl = {} local l local p = string.split(v.tags.lvl, '/')
            for _, l in ipairs(p) do _, lvl[#lvl+1] = decodeLevel(v.net, v.app, v.group, l) end
          end
          if lvl ~= nil then -- Check for levels being changed
            olvl = {}
            if mqttDevices[alias].tags.lvl then
              local l local p = string.split(mqttDevices[alias].tags.lvl, '/')
              for _, l in ipairs(p) do _, olvl[#olvl+1] = decodeLevel(v.net, v.app, v.group, l) end
            end
            local diff = difference(olvl, lvl)
            if #diff > 0 then lvlDelete[alias] = diff end
            if len(lvl) > len(olvl) then change = true end
          end
          change = true
        else
          change = true
        end
        mqttDevices[alias].tags = v.tags
        mqttDevices[alias].keywords = curr
      end
    end
    if change then
      if v.name then name = v.name else name = GetCBusGroupTag(v.net, v.app, v.group) end
      n = n + 1
      unpublished[n] = {net=v.net, app=v.app, group=v.group, channel=v.channel, tags=v.tags, name=name}
      queued[#queued + 1] = alias
    end
  end
  if n > 0 then log('Queued '..n..' object'..(n ~= 1 and 's' or '')..' with keyword MQTT for publication: '..table.concat(queued, ', ')) end

  -- Handle deletions
  local kill = {}
  for alias, v in pairs(mqttDevices) do
    local topic, oid, trigger
    if not found[alias] then
      kill[#kill + 1] = alias
      if v.app == 202 and v.type == 'button' then
        for _, trigger in ipairs(v.trigger) do
          topic = mqttDiscoveryTopic..v.type..'/'..trigger..'/config'
      	  client:publish(topic, '', mqttQoS, RETAIN); log('Removed discovery topic '..topic)
          local t = tonumber(string.match(trigger, '_(%w+)$'))
          local act, tk, tv
          for tk, tv in pairs(triggers[v.group]) do
            if t == tv then act = tk break end
          end
          t = mqttWriteTopic..alias..'/'..act..'/press'
          if mqttJunk then client:publish(t, 'junk', mqttQoS, RETAIN) end -- Publish junk to all topics to be deleted to ensure that they are actually deleted (some topics may not have been written yet)
          client:publish(t, '', mqttQoS, RETAIN)
        end
      else
        topic = mqttDiscoveryTopic..v.type..'/'..v.oid..'/config'
      	client:publish(topic, '', mqttQoS, RETAIN); log('Removed discovery topic '..topic)
        local count
        _, count = alias:gsub('/','')
        if count == 3 then -- Measurement application
          topic = mqttReadTopic..lastSlashToUnderscore(alias)
        else
          topic = mqttReadTopic..alias
        end
        if mqttJunk then client:publish(topic..'/state', 'junk', mqttQoS, RETAIN) end
        client:publish(topic..'/state', '', mqttQoS, RETAIN)
        if mqttJunk then client:publish(topic..'/level', 'junk', mqttQoS, RETAIN) end
        client:publish(topic..'/level', '', mqttQoS, RETAIN)
        if v.type == 'select' then
          if mqttJunk then client:publish(topic..'/select', 'junk', mqttQoS, RETAIN) end
          client:publish(topic..'/select', '', mqttQoS, RETAIN)
        end
        includeUnits[alias] = nil
      end
    else
      -- Handle trigger level removal
      if lvlDelete[alias] ~= nil and triggers[v.group] then
        for _, lvl in ipairs(lvlDelete[alias]) do
          local a, i, t, act = nil
          for a, t in pairs(triggers[v.group]) do if t == lvl then act = a; break end end
          local remove = nil
          if act then
            trigger = nil
            for i, t in ipairs(v.trigger) do if lvl == tonumber(string.match(t, '_(%w+)$')) then trigger = t; remove = i; break end end
            if trigger then
              topic = mqttDiscoveryTopic..v.type..'/'..trigger..'/config'
              client:publish(topic, '', mqttQoS, RETAIN); log('Remove discovery topic for '..topic..' (trigger level '..lvl..')')
              t = mqttWriteTopic..alias..'/'..act..'/press'
              if mqttJunk then client:publish(t, 'junk', mqttQoS, RETAIN) end -- Publish junk to topic to be deleted (some topics may not have been written yet)
              client:publish(t, '', mqttQoS, RETAIN)
              triggers[v.group][act] = nil
            end
            if remove then table.remove(v.trigger, remove) end
          end
        end
      end
    end
  end
  for _, k in ipairs(kill) do mqttDevices[k] = nil end
  if logging then log('cudCBusTopics() completed in '..string.format('%.3f', socket.gettime()-nClock)..' seconds') end
end


--[[
Publish queued CBus discovery topics
--]]
local function outstandingPublish()
  local nClock = socket.gettime()
  local u
  local failed = 0
  local inbound = 0
  local stat, err

  for _, u in ipairs(unpublished) do
    stat, err = pcall(addDiscover, u.net, u.app, u.group, u.channel, u.tags, u.name)
    if not stat then
      failed = failed + 1
      log(err)
    end
    if u.tags.isensor then inbound = inbound + 1 end
    -- Publish current levels
    local alias = u.net..'/'..u.app..'/'..u.group
    -- Measurement application
    if u.app == 228 then
      alias = alias..'/'..u.channel
      local level = nil; pcall(function () level = GetCBusMeasurement(u.net, u.group, u.channel) end)
      if level ~= nil then stat, err = pcall(publishMeasurement, alias, u.net, u.group, u.channel, level) if not stat then log(err) end end
    -- User parameters
    elseif u.app == 250 then stat, err = pcall(publish, alias, u.app, GetUserParam(u.net, u.group), true) if not stat then log(err) end
    -- Unit parameters
    elseif u.app == 255 then
      alias = alias..'/'..u.channel
      local level = nil; pcall(function () level = GetUnitParameter(u.net, u.group, u.channel) end)
      if level ~= nil then stat, err = pcall(publishUnitParam, alias, level) if not stat then log(err) end end
    -- Lighting and other
    else
      if not lightingButton[u.net..'/'..u.app..'/'..u.group] then -- Do nothing for lighting buttons
        local level = nil;
        if u.app == 202 then
          pcall(function () level = GetTriggerLevel(u.group) end)
        else
          pcall(function () level = GetCBusLevel(u.net, u.app, u.group) end)
        end
        if level ~= nil then stat, err = pcall(publish, alias, u.app, level, true) if not stat then log(err) end end
      end
    end
  end
  if #unpublished > 0 then
    -- Ensure that newly tagged/removed groups with the MQTT keyword send updates
    log(
      'Published '..#unpublished - failed - inbound..' CBus discovery and current level topic'..(#unpublished - failed - inbound ~= 1 and 's' or '')..
      (inbound > 0 and ', and configured '..inbound..' inbound subscription'..(inbound > 1 and 's' or '') or '')..
      (logms and ' in '..string.format('%.3f', socket.gettime()-nClock)..' seconds' or '')..
      (failed > 0 and ' ('..failed..' failed)' or '')
    )
    unpublished = {}
  end
end


--[[
Publish queued Airtopia topics
--]]
local function outstandingAtPublish()
  local nClock = socket.gettime()
  local u
  local failed = 0
  local stat, err

  for _, u in ipairs(unpublishedAt) do
    stat, err = pcall(addAtDiscover, u.name, u.sa, nil)
    if not stat then
      failed = failed + 1
      log(err)
    end
  end
  if #unpublishedAt > 0 then
    log('Published '..#unpublishedAt..' Airtopia discovery topic and current levels'..(#unpublishedAt ~= 1 and 's' or '')..(logms and ' in '..string.format('%.3f', socket.gettime()-nClock)..' seconds' or '')..(failed ~= 0 and ' ('..failed..' failed)' or ''))
    unpublishedAt = {}
  end
  stat, err = pcall(publishAtState) if not stat then log(err) end
end


--[[
Publish the next queued messages for CBus
--]]
local function outstandingMqttMessage()
  local msg, k, v, device
  for _, msg in ipairs(mqttMessages) do
    local topic = msg.topic
    local payload = msg.payload

    local parts = string.split(topic, '/')

    -- Messages from CBus write topics
    if parts[1] == 'cbus' and parts[2] == 'write' then
      local net = tonumber(parts[3]) local app = tonumber(parts[4]) local group = tonumber(parts[5])
      local alias = net..'/'..app..'/'..group
      if logging then log('Set '..topic..' to '..payload) end

      -- ignoreMqtt[alias] = socket.gettime(); if logging then log('Setting ignoreMqtt for '..alias) end

      if not parts[6] then
        log('MQTT error: Invalid message format: '..topic)

      elseif parts[6] == 'switch' then
        if payload == 'ON' then      grp.write(alias, 255); if logging then log('Payload is ON for '..alias) end
        elseif payload == 'OFF' then grp.write(alias, 0);   if logging then log('Payload is OFF for '..alias) end
        end

      elseif parts[6] == 'select' then
        if app ~= 202 then
          SetCBusLevel(net, app, group, selects[alias][payload], 0); if logging then log('Payload is '..payload..' ('..selects[alias][payload]..') for '..alias) end
        else
          SetTriggerLevel(group, selects[alias][payload], 0); if logging then log('Payload is '..payload..' ('..selects[alias][payload]..') for '..alias) end
        end

      elseif parts[6]:contains('press') and payload == 'PRESS' then -- Lighting group press
        PulseCBusLevel(net, app, group, 255, 0, 1, 0); if logging then log('Payload for '..alias..' is PRESS') end

      elseif parts[7] ~= nil and parts[7]:contains('press') and payload == 'PRESS' then -- Trigger level press
        local level = triggers[group][parts[6]]
        if level ~= nil then
          SetTriggerLevel(group, level); if logging then log('Payload for '..alias..' is PRESS') end
        else
          log('Warning: MQTT trigger level received that is not published')
        end

      elseif parts[6] == 'measurement' then SetCBusMeasurement(net, app, group, payload, 0)

      elseif parts[6] == 'ramp' then
        if payload == 'OPEN' then
          SetCBusLevel(net, app, group, 255, 0)
          if cover[alias] and not mqttDevices[alias].noleveltranslate and hasMembers(mqttDevices[alias].rate) and not transition[alias] then transition[alias] = { state='opening', level=coverLevel[alias], ts=socket.gettime() + mqttDevices[alias].delay, } if logging then log('Transitioning '..alias..' to open') end end
          goto next
        elseif payload == 'CLOSE' then
          SetCBusLevel(net, app, group, 0, 0)
          if cover[alias] and not mqttDevices[alias].noleveltranslate and hasMembers(mqttDevices[alias].rate) and not transition[alias] then transition[alias] = { state='closing', level=coverLevel[alias], ts=socket.gettime() + mqttDevices[alias].delay, } if logging then log('Transitioning '..alias..' to close') end end
          goto next
        elseif payload == 'STOP' then
          if not mqttDevices[alias].noleveltranslate then
            storage.set('coverLevel', coverLevel) transition[alias] = nil if logging then log('Cancel transition for '..alias) end
            if hasMembers(mqttDevices[alias].rate) then client:publish(mqttReadTopic..alias..'/state', (coverLevel[alias] ~= 0) and 'open' or 'closed', mqttQoS, RETAIN) end
            if setCoverLevelAtStop and hasMembers(mqttDevices[alias].rate) then SetCBusLevel(net, app, group, coverLevel[alias], 0) else SetCBusLevel(net, app, group, 5, 0) end
          end
          goto next
        elseif payload == 'ON' then
          if fan[alias] then
            if lastLevel[alias] then
              payload = lastLevel[alias]; if logging then log('Payload for '..alias..' is fan ON, so using lastlevel instead') end
            else
              payload = '255'; if logging then log('Payload for '..alias..' is fan ON') end
            end
          else
            if logging then log('Payload for '..alias..' is ON') end
            SetCBusLevel(net, app, group, 255, 0)
            goto next
          end
        end
        if payload == 'OFF' then
          if logging then log('Payload for '..alias..' is OFF') end
          SetCBusLevel(net, app, group, 0, 0)
        else -- Ramp
          parts = string.split(payload, ',')
          local lev = tonumber(parts[1])
          local num
          if lev ~= nil then num = math.floor(lev + 0.5) else log('Warning: non-numeric CBus level for '..alias..', level='..parts[1]); num = nil end
          if num ~= nil and num < 256 then
            if logging then log('Payload for '..alias..' is RAMP '..payload) end
            local toSet = 0
            local ramp = 0
            if not fan[alias] then
              if lastLevel[alias] and not storeLevel[alias] then lastLevel[alias] = nil storage.set('lastlvl', lastLevel) log('Clear legacy lastLevel for '..alias) end
              if storeLevel[alias] and lastLevel[alias] then if logging then log('Last level '..lastLevel[alias]) end end
              if storeLevel[alias] and lastLevel[alias] and num == 255 then
                if blindKey and GetCBusGroupTag(net, app, group):contains(blindKey) then
                  toSet = num; if logging then log('Payload is blind ramp on for '..alias) end
                else
                  if lastLevel[alias] then toSet = lastLevel[alias] else toSet = num end
                end
              else
                toSet = num
              end
              if cover[alias] then
                coverLevel[alias] = toSet storage.set('coverLevel', coverLevel) mqttDevices[alias].transition = nil
                if hasMembers(mqttDevices[alias].rate) then client:publish(mqttReadTopic..alias..'/state', (coverLevel[alias] ~= 0) and 'open' or 'closed', mqttQoS, RETAIN) end
              end
            else
              toSet = num
            end
            if parts[2] ~= nil then ramp = tonumber(parts[2]) else ramp = 0 end
            SetCBusLevel(net, app, group, toSet, ramp)
          end
          goto next
        end
      end

    elseif inbound[topic] then
      if logging then log('Set '..inbound[topic].alias..' to '..payload) end
      local value = tonumber(payload) if value == nil then value = payload end
      grp.write(inbound[topic].alias, value)

    -- Messages from ENV board sensor topics - simpler, only messages inbound
    elseif environmentSupport and envBoards[parts[1]] and parts[2] == 'sensor' and parts[4] == 'state' then
      device = parts[1]..'-'..parts[3]
      if envDevices[device] then
        local extant = GetUserParam(envDevices[device][1], envDevices[device][2])
        if type(extant) == 'number' then
          -- Deal with real number imprecision, assuming three decimal places for change detection
          if string.format('%.3f', extant) ~= string.format('%.3f', tonumber(payload)) then SetUserParam(envDevices[device][1], envDevices[device][2], payload) end
        else
          if extant ~= payload then SetUserParam(net, group, payload) end
        end
        env[envDevices[device][3]].state = payload
      end

    -- Messages from AC board select/sensor topics
    elseif panasonicSupport and acBoards[parts[1]] and acMsg[parts[2]] then
      local sel = 'func'
      if parts[2] == 'select' then
        sel = 'sel'
      else
        local a = acSense[parts[1]..'-'..parts[3]] if a and ac[a].sense == parts[3] and ac[a].topic == parts[2] then sel = 'sense' device = parts[1]..'-'..parts[3]..'-sense' end
        if not a then if parts[4] then a = acSense[parts[1]..'-'..parts[4]] end if a and ac[a].sense == parts[4] and ac[a].topic == parts[2] then sel = 'sense' device = parts[1]..'-'..parts[4]..'-sense' end end
      end
      if sel == 'func' then device = parts[1]..'-'..parts[4] elseif sel == 'select' then device = parts[1]..'-'..parts[3] end
      local net, group
      if acDevices[device] then
        local alias = acDevices[device]
        net = ac[alias].net
        group = ac[alias].group
        if (sel == 'func' and parts[5] == 'state') or (sel == 'sel' and parts[4] == 'state') or sel == 'sense' then
          if ignoreCbus[alias] and socket.gettime() - ignoreCbus[alias] > ignoreTimeout then -- Don't worry about older 'ignore' flags
            ignoreCbus[alias] = nil
            if logging then log('Ignoring older CBus ignore flag for '..alias) end
          end
          if not ignoreCbus[alias] then -- Only set the CBus status/level if this script did not initiate the change, and if it is different to the current value
            local set = false
            if payload ~= nil then
              local extant = GetUserParam(net, group)
              local e = tonumber(extant)
              local p = tonumber(payload)
              if e ~= nil and p ~= nil then
                if string.format('%.3f', e) ~= string.format('%.3f', p) then SetUserParam(net, group, p); set = true end
              elseif p ~= nil then
                if e ~= string.format('%.3f', p) then SetUserParam(net, group, p); set = true end
              elseif e ~= nil then
                if string.format('%.3f', e) ~= payload then SetUserParam(net, group, payload); set = true end
              else
                if extant ~= payload then SetUserParam(net, group, payload); set = true end
              end
            else
              log('Warning: nil payload for '..alias..', ignoring')
            end
            if set then
              ignoreMqtt[alias] = socket.gettime()
              -- if logging then log('Setting ignoreMqtt for '..alias..', oldState='..extant..' payload='..payload) end
            end
          else
            ignoreCbus[alias] = nil
            if logging then log('Ignoring CBus publish for '..alias) end
          end
          ac[alias].state = payload
        end
      end

    -- Messages from AT board cmd topics
    elseif airtopiaSupport and parts[1] == 'airtopia' and parts[3] == 'cmd' then
      device = parts[2]..'-'..parts[4]
      local net, group

      local function pub(alias, payload) -- State publish to MQTT
        local parts = string.split(at[alias].name, '-')
        local board = parts[1]
        local topic = 'airtopia/'..board..'/state/'..parts[2]
        client:publish(topic, payload, mqttQoS, RETAIN)
      end

      if parts[4] == 'mode' then
        if atDevices[device] then
          alias = atDevices[device]
          local p = string.split(alias, '/'); net = tonumber(p[1]); group = tonumber(p[3])
          i = indexOf(atmodes, payload)
          if i ~= nil then
            local set = false
            local pwrgrp = tonumber(string.split(atBoards[parts[2]].alias, '/')[3]) -- Get the power user parameter
            local extant = GetUserParam(net, pwrgrp)
            local pld = nil
            if payload ~= 'off' then
              pub(alias, i)
              pub(atBoards[parts[2]].alias, 1) -- Power on
              if extant ~= 1 then set = true; pld = 1 end
            else
              pub(atBoards[parts[2]].alias, 0) -- Power off
              if extant ~= 0 then set = true; pld = 0 end
            end
            if set and pld ~= nil then
              -- Send to CBus, ensuring MQTT ignore is set...
              local alias = atBoards[parts[2]].alias
              ignoreMqtt[alias] = socket.gettime(); if logging then log('Setting ignoreMqtt for '..alias..', oldState='..extant..' payload='..pld) end
              SetUserParam(net, pwrgrp, pld)
            end
            -- publish to CBus
            local extant = GetUserParam(net, group)
            if i ~= extant and payload ~= 'off' then -- Set mode, but not if it is 'off'
              ignoreMqtt[alias] = socket.gettime(); if logging then log('Setting ignoreMqtt for '..alias..', oldState='..extant..' payload='..payload) end
              SetUserParam(net, group, i)
            end
          end
          -- Publish state to broker
          local parts = string.split(at[alias].name, '-')
          local board = parts[1]
          local topic = 'airtopia/'..board..'/state/modeha'
          client:publish(topic, payload, mqttQoS, RETAIN)
        end

      elseif parts[4] == 'swing' then
        local hswing = atDevices[parts[2]..'-horiz_swing']
        local vswing = atDevices[parts[2]..'-vert_swing']
        if hswing ~= nil and vswing ~= nil then
          local i, h, v
          local s = 0; for i, v in ipairs(atswings) do if v == payload then s = i - 1; break; end end -- Get the swing index
          h = bit.band(s, 1)
          v = bit.rshift(bit.band(s, 2), 1)
          local board = parts[2]
          local topic = 'airtopia/'..board..'/state/swingha'
          client:publish(topic, payload, mqttQoS, RETAIN)
          parts = string.split(hswing, '/'); SetUserParam(parts[1], parts[3], h)
          parts = string.split(vswing, '/'); SetUserParam(parts[1], parts[3], v)
        end

      elseif parts[4] == 'fan' then
        local fan = atDevices[parts[2]..'-fan']
        if fan ~= nil then
          local i, f
          local f = 0; for i, v in ipairs(atfans) do if v == payload then f = i - 1; break; end end -- Get the fan index
          local board = parts[2]
          local topic = 'airtopia/'..board..'/state/fanha'
          client:publish(topic, payload, mqttQoS, RETAIN)
          parts = string.split(fan, '/'); SetUserParam(parts[1], parts[3], f)
        end

      else -- Set target temp
        if atDevices[device] then
          alias = atDevices[device]
          local p = string.split(alias, '/'); net = tonumber(p[1]); group = tonumber(p[3])
          pub(alias, payload)
          -- publish to CBus
          local extant = GetUserParam(net, group)
          if payoad ~= extant then
            ignoreMqtt[alias] = socket.gettime(); if logging then log('Setting ignoreMqtt for '..alias..', oldState='..extant..' payload='..payload) end
            SetUserParam(net, group, payload)
          end
        end
      end
    elseif airtopiaSupport and parts[1] == 'airtopia' and parts[3] == 'state' then
      if indexOf(airtopiaStates, parts[4]) == nil then airtopiaStates[#airtopiaStates + 1] = parts[4] end
    end
    ::next::
  end
  mqttMessages = {}
end


--[[
Publish the next queued messages for MQTT
--]]
local function outstandingCbusMessage()
  local cmd, stat, err, alias, final

  for _, cmd in ipairs(cbusMessages) do
    alias = cmd.alias

    if panasonicSupport and ac[alias] then -- AC message to MQTT (no ramping involved for AC groups)
      stat, err = pcall(publishAc, alias, cmd.value, ac[alias].select)
      if not stat then log(err) end
    elseif airtopiaSupport and at[alias] then -- AT message to MQTT (no ramping involved for AT groups)
      stat, err = pcall(publishAt, alias, cmd.value)
      if not stat then log(err) end
    else -- CBus message to MQTT
      if cmd.app ~= 228 and cmd.app ~= 255 then -- i.e. not measurement application / unit parameter
        local payload = tonumber(cmd.value) -- Always a number for lighting app, but payload could be nil for user param at this point if a string
        if not lighting[tostring(cmd.app)] then -- Possibly a string payload for user parameter
          if payload == nil then
            payload = cmd.value
          end
        end
        stat, err = pcall(publish, alias, cmd.app, payload) if not stat then log(err) end
        if cover[alias] and not mqttDevices[alias].noleveltranslate and hasMembers(mqttDevices[alias].rate) then
          if not transition[alias] then
            if payload == 0 then transition[alias] = { state='closing', level=coverLevel[alias], ts=socket.gettime() + mqttDevices[alias].delay, } if logging then log('Transitioning '..alias..' to open') end
            elseif payload == 255 then transition[alias] = { state='opening', level=coverLevel[alias], ts=socket.gettime() + mqttDevices[alias].delay, } if logging then log('Transitioning '..alias..' to closed') end
            end
          else
            if payload == 5 then
              storage.set('coverLevel', coverLevel) transition[alias] = nil if logging then log('Cancel transition for '..alias) end
              if hasMembers(mqttDevices[alias].rate) then client:publish(mqttReadTopic..alias..'/state', (coverLevel[alias] ~= 0) and 'open' or 'closed', mqttQoS, RETAIN) end
            end
          end
        end
      elseif cmd.app == 228 then -- Special case for measurement app
        stat, err = pcall(publishMeasurement, alias, cmd.net, cmd.group, cmd.channel, tonumber(cmd.value)) if not stat then log(err) end
      elseif cmd.app == 255 then -- Special case for unit param
        stat, err = pcall(publishUnitParam, alias, tonumber(cmd.value)) if not stat then log(err) end
      end
    end
  end
  cbusMessages = {}
end


--[[
Duplicate discovery delete
--]]
local function dupDelete()
  -- If duplicate discovery topics are detected then remove them (discoveryDelete is set in broker ON_MESSAGE call-back)
  log('Warning: Removing '..len(discoveryDelete)..' duplicate discovery topics')
  local toDelete
  for toDelete, _ in pairs(discoveryDelete) do
    local parts = string.split(toDelete, '/')
    local oid = parts[1]
    local dType = parts[2]
    if mqttJunk then client:publish(mqttDiscoveryTopic..dType..'/'..oid..'/config', 'junk', mqttQoS, RETAIN) end
    client:publish(mqttDiscoveryTopic..dType..'/'..oid..'/config', '', mqttQoS, RETAIN)
    log('Removed discovery topic '..mqttDiscoveryTopic..dType..'/'..oid..'/config')
  end
  discoveryDelete = {}
end


local function checkHeartbeat()
  if sendHeartbeat > 0 then
    local stat, err = pcall(function ()
      if socket.gettime() - heartbeat >= sendHeartbeat then
        heartbeat = socket.gettime(); require('socket').udp():sendto(_SCRIPTNAME..'+'..heartbeat, '127.0.0.1', 5433)
      end
    end)
    if not stat then
      log('A fault occurred sending heartbeat. Restarting...')
      return false
    else
      return true
    end
  end
  return true
end


--[[
Main loop
--]]

-- Create/update/delete functions spread evenly over the period 'checkChanges'
local cud = {
  { name = 'CBus', func = cudCBusTopics, init = false },
}
if environmentSupport then cud[#cud + 1] = { name = 'environment sensor', func = cudEnv, init = true } end
if panasonicSupport then cud[#cud + 1] = { name = 'Panasonic', func = cudAc, init = true } end
if airtopiaSupport then cud[#cud + 1] = { name = 'Airtopia', func = cudAt, init = false } end

local i, c
for i, c in ipairs(cud) do c.t = socket.gettime() - checkChanges * 1/#cud * i + checkChanges/#cud end -- Set the time to next discover for each function, spread evenly over the check changes interval

local warningTimeout = 30
local timeout = 1
local timeoutStart, connectStart

while true do
  local stat, err, k, v

  -- Check for new messages from CBus. The entire socket buffer is collected each iteration for efficiency.
  localbus:step()

  if mqttStatus == 1 then -- When connected to the broker
    -- Process MQTT message buffers synchronously - sends and receives
    client:loop(mqttTimeout)

    if #mqttMessages > 0 then
      -- Send outstanding messages to CBus
      stat, err = pcall(outstandingMqttMessage)
      if not stat then log('Error processing outstanding MQTT messages: '..err) mqttMessages = {} end -- Log error and clear the queue
    end
    if #cbusMessages > 0 then
      -- Send outstanding messages to MQTT
      stat, err = pcall(outstandingCbusMessage)
      if not stat then log('Error processing outstanding CBus messages: '..err) cbusMessages = {} end -- Log error and clear the queue, continue
    end
    if #unpublished > 0 then
      -- Publish outstanding CBus discovery topics
      stat, err = pcall(outstandingPublish)
      if not stat then log('Error publishing outstanding CBus discovery topics: '..err) unpublished = {} end -- Log error and clear the queue, continue
    end
    if #unpublishedAt > 0 then
      -- Publish outstanding Airtopia discovery topics
      stat, err = pcall(outstandingAtPublish)
      if not stat then log('Error publishing outstanding Airtopia discovery topics: '..err) unpublishedAt = {} end -- Log error and clear the queue, continue
    end
    if hasMembers(transition) then
      -- Tracking progress of open/close of covers
      stat, err = pcall(trackTransitions)
      if not stat then log('Error tracking transitions: '..err) transition = {} end -- Log error and clear the transition list, continue
    end
    if hasMembers(discoveryDelete) then
      -- A type has changed for existing topics, so clean up discovery for the old topics
      stat, err = pcall(dupDelete)
      if not stat then log('Error processing delete discovery duplicates: '..err) discoveryDelete = {} end -- Log error and clear the queue, continue
    end
    if checkForChanges then
      -- Periodically create/update/delete device items that change
      for _, c in ipairs(cud) do if socket.gettime() - c.t >=checkChanges then c.t = socket.gettime() local stat, err = pcall(c.func) if not stat then log('Error calling '..c.name..' create/update/delete function: '..err) end end end
    end
  elseif mqttStatus == 2 or not mqttStatus then
    -- MQTT is disconnected, so attempt a connection, waiting. If fail to connect then retry.
    if init then
      log('Connecting to Mosquitto broker')
      timeoutStart = socket.gettime()
      connectStart = timeoutStart
      init = false
    end
    stat, err = pcall(function (b, p, k) client:connect(b, p, k) end, mqttBroker, 1883, 25) -- Requested keep-alive 25 seconds, broker at port 1883
    if not stat then -- Log and abort
      log('Error calling connect to broker: '..err)
      do return end
    end
    while mqttStatus ~= 1 do
      client:loop(1) -- Service the client with a generous timeout
      if socket.gettime() - connectStart > timeout then
        if socket.gettime() - timeoutStart > warningTimeout then
          log('Failed to connect to the Mosquitto broker, retrying continuously')
          timeoutStart = socket.gettime()
        end
        connectStart = socket.gettime()
        goto next -- Exit to the main loop to keep socket messages monitored
      end
    end
    mqttConnected = socket.gettime()
    -- Subscribe to relevant topics
    client:subscribe(mqttWriteTopic..'#', mqttQoS)
    client:subscribe(mqttDiscoveryTopic..'#', mqttQoS)
    for k, _ in pairs(inbound) do client:subscribe(k, mqttQoS) end
    if panasonicSupport then for k, _ in pairs(acBoards) do client:subscribe(k..'/#', mqttQoS) end end
    if airtopiaSupport then for k, _ in pairs(atBoards) do client:subscribe('airtopia/'..k..'/#', mqttQoS) end end
    if environmentSupport then for k, _ in pairs(envBoards) do client:subscribe(k..'/#', mqttQoS) end end
    -- Connected... Now loop briefly to allow retained value retrieval for subscribed topics because synchronous
    while socket.gettime() - mqttConnected < 0.5 do client:loop(0) end
    if not reconnect then
      if hasMembers(discoveryDelete) then
        -- A type has changed for existing topics, so clean up discovery for the old topics
        stat, err = pcall(dupDelete)
        if not stat then log('Error processing delete discovery duplicates: '..err) discoveryDelete = {} end -- Log error and clear the queue, continue
      end
      -- Full publish CBus topics
      stat, err = pcall(publishCurrent)
      if not stat then log('Error publishing current values: '..err) end -- Log and continue
      -- Initial load of devices excluding CBus/Airtopia
      for _, c in ipairs(cud) do if c.init then local stat, err = pcall(c.func) if not stat then log('Error calling '..c.name..' create/update/delete function: '..err) end end end
    end
  else
    log('Error: Invalid mqttStatus: '..mqttStatus)
    do return end
  end

  ::next::

  --[[
  Send a heartbeat periodically to port 5433, listened to by the heartheat script.
  If execution is disrupted by any error or lockup then this script will be re-started.
  If sending the heartbeat faults, then the loop is exited, which will also re-start this
  script (it being resident/sleep zero).
  --]]
  if not checkHeartbeat() then do return end end
end