Lua: Hijack Skill

This lua script sample is taken straight from Remnants. It is a special ability that allows a unit to take control of another unit in range.
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---------------------------------------------------------------------------
-- All Content © 2014 DigiPen (USA) Corporation, All Rights Reserved
-- Filename   : Skill_Hijack.lua
-- Author(s)  : Zhuhuii Yap 
-- Created    : 12/DEC/2014
-- Description: Special ability that take control of another unit
---------------------------------------------------------------------------
-- Get Bound Parameters for Current Action
-- object - the object performing the action
-- node   - the action node of the current action being performed
local this_object, node = GetArgs()

-- Get varibles from action node
-- target_id - the id of the unit we are trying to hijack
-- range     - the range of the ability
local target_id = node:Get("TargetID")
local range     = node:Get("Range")

-- Get required systems
-- engine    - the core engine
-- factory   - the system reponsible of object
-- gamelogic - the system responsible for object's game logic
-- transformHelper - the a helper libary for transformations
local engine          = GetEngine()
local factory         = engine:GetFactory()
local gamelogic       = engine:GetGameLogic()
local transformHelper = engine:GetTransformHelper()

-- Check for target validity
if(fact:IsValid(target_id) == true)
then
  -- Target is a vaild object
  -- Get target object and required components
  local target_object = factory:GetObject(target_id)
  local target_transform = target_object:GetTransformComponent()
  
  -- Get object (this_object) required component
  local this_transform = this_object:GetTransformComponent()
  
  -- Determine if target is in range and it is a unit
  local distance = transformHelper:Distance(target_transform, this_transform)
  if(distance < range and target_object:IsUnit() == true)
  then
    -- In range and target is a unit
    -- Get target stats component
    local target_stats = target_object:GetStats()
    
    -- Get object (this_object) stats component
    local this_stats = this_object:GetStats()
    
    -- Behavior of ability does not allow you hijack building only units
    if(target_stats:IsBuilding() == false)
    then
      -- Modifiy stats component 
      target_stats.owner = this_stats.owner -- change owner
      
      -- Update game logic with the change in ownership of the object
      logic:UpdateRelevantOwners(target_object, this_stats.owner, target_stats.owner)
      
      -- Apply cooldown for successfully completed action
      local this_actionlist = this_object:GetActionList()
      this_actionlist:ApplyCooldown(node)
    end
    
  else
    -- Out of range or target is not a unit
    -- Attempt to move into range 
    -- note: MoveIntoRange will requeue the action node when it is in range
    gamelogic:MoveIntoRange(obj, range, node)
  end
end

-- Terminate action, non-looping action
node:SetComplete(obj)
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