gKH = {}; --our global namespace
gKH.dbglevel = 1; --controls amount of print and debug info.
gKH.SceneGlobals = {};  --our sceneglobals sub namespace
gKH.SceneGlobals.GenerationMarker = 0;
gKH.SceneGlobals.PerHangerChancePct = 25; --percent chance for each hanger.
gKH.SceneGlobals.RedbaseHangerMax = 3;  --cap at 6 aircraft.
gKH.SceneGlobals.RedbaseHangerCounter = 0; --keep track of how many are generated.
gKH.SceneGlobals.RedbaseAircraftCounter = 8; --starting point for aircraft names (1 gets added)
--table holding locations of 6 possible hangers.
gKH.SceneGlobals.Redbase1Hangers = {
{index=1,latitude='10.9056518851787', longitude='114.086331168915'},
{index=2,latitude='10.9046518851787', longitude='114.086331168915'},
{index=3,latitude='10.9036518851787', longitude='114.086331168915'},
{index=4,latitude='10.9026518851787', longitude='114.086331168915'},
{index=5,latitude='10.9016518851787', longitude='114.086331168915'},
{index=6,latitude='10.9006518851787', longitude='114.086331168915'}
}

--returns latitude and longitude from our table or nil upon failure.
function gKH.GetRedbaseLocation(hindex)
  local marker = false;
  for k,v in pairs(gKH.SceneGlobals.Redbase1Hangers) do
    if v.index == hindex then
       marker = true
       return v.latitude,v.longitude;
    end
  end
  return nil;
end

--generates randome seed.
function  gKH.ImprovedRandomseed(quality)
    if quality == nil then quality=10 end
    -- os.time() removes dependency on how long the software has been running currently
    -- os.clock() provides miliseconds, unlike os.time()
    -- we "chain" this with previous math.random() output to retain any accumulated entropy
    -- and "stir" a little by repeating more than once, though not much because the execution time
    -- probably doesn't vary much between calls and spending too much time will be a waste unless we want
    -- to spend several seconds doing this.
    math.randomseed(os.time() + math.random(90071992547)) -- preserve some previous entropy if there was any
    for i = 1, quality do
        -- Retain some previous PRNG state while adding a little jitter entropy, but not much.
        -- Jitter entropy comes from thread preemption, interrupt handing, and stuff like that in the OS that is
        -- somewhat random. This means you might not get much if any on a powerful and calm system.
        -- If we had a higher precision clock with ns instead of just ms then that would be more helpful.
        math.randomseed(((os.clock() * 1000) % 1000) + math.random(900719925470000))
    end
end

--handles our dicerolling.
function gKH.RandomDiceRoll(pct)
  gKH.ImprovedRandomseed(10) -- reinitialize the random number generator with a new seed once per function use.  
  local r = math.random(1,1000) -- get randome number between 1 and 1000; 1000 adds maybe more variabily in sequence?
  if gKH.dbglevel > 0 then print('RandomDiceRoll(): random number gen: ' .. tostring(r)); end
  
  if (r <= (pct * 10)) then  -- is random less than or equal to our set percentage?
    if gKH.dbglevel > 1 then print('RandomDiceRoll(): Match! returning true'); end
    return true; 
  else 
    return false;
  end 
end


--creates hangers and aircraft, does group and mission assignment 
function gKH.CreateHangerUnitPackage(theside,hangerindex,idbid,iloadout,strmission)
local retval = true;
local lat,lon = gKH.GetRedbaseLocation(hangerindex)
  if lat ~=nil and lon ~=nil then
    --add hanger.
    local h = ScenEdit_AddUnit({type = 'Facility', name = 'RedAirbase_Hanger_' .. hangerindex, 
    heading = 0, dbid = 41, side = theside, Latitude=lat,Longitude=lon,
    altitude="3 ft",autodetectable="false",holdfire="true",proficiency=4});
    
    
    if h ~=nil then
      h.group = "Red_Airbase"; --add new hanger to the base.

      gKH.SceneGlobals.RedbaseAircraftCounter = gKH.SceneGlobals.RedbaseAircraftCounter + 1;
      local u = ScenEdit_AddUnit({type = 'Aircraft', name = 'Argonaut #' .. gKH.SceneGlobals.RedbaseAircraftCounter, loadoutid = iloadout,
      heading = 0, dbid = idbid, side = theside, Latitude=lat,Longitude=lon,
      altitude="36100 ft",autodetectable="false",holdfire="true",proficiency=4,speed=350,base=h.name});

      ScenEdit_SetLoadout({UnitName=u.guid,loadoutID=0,TimeToReady_Minutes=0,IgnoreMagazines=true})
      ScenEdit_AssignUnitToMission (u.guid, strmission) 


      gKH.SceneGlobals.RedbaseAircraftCounter = gKH.SceneGlobals.RedbaseAircraftCounter + 1;
      local u = ScenEdit_AddUnit({type = 'Aircraft', name = 'Argonaut #' .. gKH.SceneGlobals.RedbaseAircraftCounter, loadoutid = iloadout,
      heading = 0, dbid = idbid, side = theside, Latitude=lat,Longitude=lon,
      altitude="36100 ft",autodetectable="false",holdfire="true",proficiency=4,speed=350,base=h.name});

      ScenEdit_SetLoadout({UnitName=u.guid,loadoutID=0,TimeToReady_Minutes=0,IgnoreMagazines=true})
      ScenEdit_AssignUnitToMission (u.guid, strmission) 
    else
      print("Hanger creation failed.");
      retval = false;
    end
  else
    print("Hanger location lookup failed.");
    retval = false;
  end
  return retval
end

local function DoRandomHangerGeneration()
  for i = 1, #gKH.SceneGlobals.Redbase1Hangers do
    if gKH.RandomDiceRoll(gKH.SceneGlobals.PerHangerChancePct) == true then
       if gKH.SceneGlobals.RedbaseHangerCounter  < gKH.SceneGlobals.RedbaseHangerMax then  --Dont do more than 6 aircraft.
         if gKH.CreateHangerUnitPackage('Red',i,4449,22439,'Fiery Cross CAP 1') == true then
           gKH.SceneGlobals.RedbaseHangerCounter = gKH.SceneGlobals.RedbaseHangerCounter + 1
         else
           print("an error occured generating hanger or aircreaft for index#" .. i); 
         end
       else
         if gKH.dbglevel > 0 then print("Skipping, Maximum hangers reached.") end
       end
    end
  end
  gKH.SceneGlobals.GenerationMarker = 1; --update global value
  ScenEdit_SetKeyValue("HangerGenerationMarker",gKH.SceneGlobals.GenerationMarker); --save to file.
end


local function CheckHangerGeneration()
  local tmp = ScenEdit_GetKeyValue("HangerGenerationMarker") --get from save file if exists.
  if tmp == nil or tmp == "" then 
    gKH.SceneGlobals.GenerationMarker = 0;  --does not exit, set to 0
  else
    gKH.SceneGlobals.GenerationMarker = tonumber(tmp); --exists convert to number.
  end
  if gKH.SceneGlobals.GenerationMarker < 1 then  
    --attempt to create them otherwise it's already done and > 0 is read from the savefile.
    DoRandomHangerGeneration();
  else
    print("HangerGenerationMarker active in save already. Skipping.")
  end
end

---end functions --
print("---")
CheckHangerGeneration()