TIMERS_VERSION = "1.05"

--[[

  -- A timer running every second that starts immediately on the next frame, respects pauses
  Timers:CreateTimer(function()
      print ("Hello. I'm running immediately and then every second thereafter.")
      return 1.0
    end
  )

  -- The same timer as above with a shorthand call
  Timers(function()
    print ("Hello. I'm running immediately and then every second thereafter.")
    return 1.0
  end)


  -- A timer which calls a function with a table context
  Timers:CreateTimer(GameMode.someFunction, GameMode)

  -- A timer running every second that starts 5 seconds in the future, respects pauses
  Timers:CreateTimer(5, function()
      print ("Hello. I'm running 5 seconds after you called me and then every second thereafter.")
      return 1.0
    end
  )

  -- 10 second delayed, run once using gametime (respect pauses)
  Timers:CreateTimer({
    endTime = 10, -- when this timer should first execute, you can omit this if you want it to run first on the next frame
    callback = function()
      print ("Hello. I'm running 10 seconds after when I was started.")
    end
  })

  -- 10 second delayed, run once regardless of pauses
  Timers:CreateTimer({
    useGameTime = false,
    endTime = 10, -- when this timer should first execute, you can omit this if you want it to run first on the next frame
    callback = function()
      print ("Hello. I'm running 10 seconds after I was started even if someone paused the game.")
    end
  })


  -- A timer running every second that starts after 2 minutes regardless of pauses
  Timers:CreateTimer("uniqueTimerString3", {
    useGameTime = false,
    endTime = 120,
    callback = function()
      print ("Hello. I'm running after 2 minutes and then every second thereafter.")
      return 1
    end
  })


  -- A timer using the old style to repeat every second starting 5 seconds ahead
  Timers:CreateTimer("uniqueTimerString3", {
    useOldStyle = true,
    endTime = GameRules:GetGameTime() + 5,
    callback = function()
      print ("Hello. I'm running after 5 seconds and then every second thereafter.")
      return GameRules:GetGameTime() + 1
    end
  })

]]



TIMERS_THINK = 0.01

if Timers == nil then
  print ( '[Timers] creating Timers' )
  Timers = {}
  setmetatable(Timers, {
    __call = function(t, ...)
      return t:CreateTimer(...)
    end
  })
  --Timers.__index = Timers
end

function Timers:start()
  Timers = self
  self.timers = {}

  --local ent = Entities:CreateByClassname("info_target") -- Entities:FindByClassname(nil, 'CWorld')
  local ent = SpawnEntityFromTableSynchronous("info_target", {targetname="timers_lua_thinker"})
  ent:SetThink("Think", self, "timers", TIMERS_THINK)
end

function Timers:Think()
  --if GameRules:State_Get() >= DOTA_GAMERULES_STATE_POST_GAME then
    --return
  --end

  -- Track game time, since the dt passed in to think is actually wall-clock time not simulation time.
  local pre_loop_now = GameRules:GetGameTime()

  -- Process timers
  for k,v in pairs(Timers.timers) do
    local bUseGameTime = true
    if v.useGameTime ~= nil and v.useGameTime == false then
      bUseGameTime = false
    end
    local bOldStyle = false
    if v.useOldStyle ~= nil and v.useOldStyle == true then
      bOldStyle = true
    end

    local now = pre_loop_now
    if not bUseGameTime then
      now = Time()
    end

    if v.endTime == nil then
      v.endTime = now
    end
    -- Check if the timer has finished
    if now >= v.endTime then
      -- Remove from timers list
      Timers.timers[k] = nil

      Timers.runningTimer = k
      Timers.removeSelf = false

      -- Run the callback
      local status, nextCall
      if v.context then
        status, nextCall = xpcall(function() return v.callback(v.context, v) end, function (msg)
                                    return msg..'\n'..debug.traceback()..'\n'
                                  end)
      else
        status, nextCall = xpcall(function() return v.callback(v) end, function (msg)
                                    return msg..'\n'..debug.traceback()..'\n'
                                  end)
      end

      Timers.runningTimer = nil

      -- Make sure it worked
      if status then
        -- Check if it needs to loop
        if nextCall and not Timers.removeSelf then
          -- Change its end time

          if bOldStyle then
            v.endTime = v.endTime + nextCall - now
          else
            v.endTime = v.endTime + nextCall
          end

          Timers.timers[k] = v
        end

        -- Update timer data
        --self:UpdateTimerData()
      else
        -- Nope, handle the error
        Timers:HandleEventError('Timer', k, nextCall)
      end
    end
  end

  return TIMERS_THINK
end

function Timers:HandleEventError(name, event, err)
  print(err)

  -- Ensure we have data
  name = tostring(name or 'unknown')
  event = tostring(event or 'unknown')
  err = tostring(err or 'unknown')

  -- Tell everyone there was an error
  --Say(nil, name .. ' threw an error on event '..event, false)
  --Say(nil, err, false)

  -- Prevent loop arounds
  if not self.errorHandled then
    -- Store that we handled an error
    self.errorHandled = true
  end
end

function Timers:RemainingTime(name)
  --Calculates Remaining Time on a given timer
  local v = Timers.timers[name]
  local bUseGameTime = true
  if v.useGameTime ~= nil and v.useGameTime == false then
    bUseGameTime = false
  end
  local bOldStyle = false
  if v.useOldStyle ~= nil and v.useOldStyle == true then
    bOldStyle = true
  end
  local now = GameRules:GetGameTime()
  if not bUseGameTime then
    now = Time()
  end

  if v.endTime == nil then
    v.endTime = now
  end

  return v.endTime - now
end

function Timers:CreateTimer(name, args, context)
  if type(name) == "function" then
    if args ~= nil then
      context = args
    end
    args = {callback = name}
    name = DoUniqueString("timer")
  elseif type(name) == "table" then
    args = name
    name = DoUniqueString("timer")
  elseif type(name) == "number" then
    args = {endTime = name, callback = args}
    name = DoUniqueString("timer")
  end
  if not args.callback then
    print("Invalid timer created: "..name)
    return
  end


  local now = GameRules:GetGameTime()
  if args.useGameTime ~= nil and args.useGameTime == false then
    now = Time()
  end

  if args.endTime == nil then
    args.endTime = now
  elseif args.useOldStyle == nil or args.useOldStyle == false then
    args.endTime = now + args.endTime
  end

  args.context = context

  Timers.timers[name] = args

  return name
end

function Timers:RemoveTimer(name)
  Timers.timers[name] = nil
  if Timers.runningTimer == name then
    Timers.removeSelf = true
  end
end

function Timers:RemoveTimers(killAll)
  local timers = {}
  Timers.removeSelf = true

  if not killAll then
    for k,v in pairs(Timers.timers) do
      if v.persist then
        timers[k] = v
      end
    end
  end

  Timers.timers = timers
end

if not Timers.timers then Timers:start() end

GameRules.Timers = Timers
