-- 17.02.17/AH Problem A2A Cessna C172 Alternator on CH Throttle Quadrant not working
-- 				Found LUA Script in https://a2asimulations.com/forum/viewtopic.php?f=108&t=37894
--				but it doesn't work as toggle so I modified it
--				Offsets 0x3102 / 0x3101 not used for A2A: FSUIPC internal memory for Alternator and Battery
--				A2A C172: If Alternator switched on, Battery goes on to to avoid spikes
--				(Battery without Alternator: ok, Alternator without Battery: not ok)
-- 11.05.18/AH	Changed for TT On/Off-Switches: ipcPARAM=1/2 -> On/Off, don't need Toggle part but left it for documentation
--
--	This script can be mapped to Alternator Toggle Switch for A2A C172 Cessna
--
ALTERNATOR = ipc.readLvar("L:Eng1_GeneratorSwitch")
BATTERY = ipc.readLvar("L:Battery1Switch")
-- 
-- Activate the following code for debugging this script:
-- ipc.setdisplay(300,500,500,200)
-- ipc.lineDisplay("ALT State on Entry:" .. ALTERNATOR,1)
-- ipc.lineDisplay("BAT State on Entry:" .. BATTERY,2)
--
--
-- Parm 1/2 : Alternator on/off (if "on", battery has to go "on" too)
--
if ipcPARAM == 1 then -- Battery + Alternator switches both on
  if (BATTERY == 0) then
    ipc.writeLvar("L:Battery1Switch", 1)
    ipc.sleep(200)   
  end  
  ipc.writeLvar("L:Eng1_GeneratorSwitch", 1)
  return
elseif ipcPARAM == 2 then -- Alternator switch off (battery switch untouched)
  ipc.writeLvar("L:Eng1_GeneratorSwitch", 0)
  return
--
-- Parm 3 : Toggle Alternator on/off (and switch battery to "on" if alternator goes to "on")
--
elseif ipcPARAM == 3 then
  if (ALTERNATOR == 0) then
    if (BATTERY == 0) then
      ipc.writeLvar("L:Battery1Switch", 1)
      ipc.sleep(100)   
    end  
    ipc.writeLvar("L:Eng1_GeneratorSwitch", 1)
  else
    ipc.writeLvar("L:Eng1_GeneratorSwitch", 0)
  end
--
-- ipcPARAM not implemented
--
else
  ipc.log("ipcPARAM " .. ipcPARAM .. " unhandled")  
end
-- Just for debugging
-- ALTERNATOR = ipc.readLvar("L:Eng1_GeneratorSwitch")
-- BATTERY = ipc.readLvar("L:Battery1Switch")
-- ipc.setdisplay(300,500,500,200)
-- ipc.lineDisplay("ALT State on Exit:" .. ALTERNATOR,3)
-- ipc.lineDisplay("BAT State on Exit:" .. BATTERY,4)
-- ipc.sleep(5000)
-- End of debugging