desc "Change topic/post ownership of all the topics/posts by a specific user (without creating new revision)"
task "users:change_post_ownership", [:old_username, :new_username, :archetype] => [:environment] do |_, args|
  old_username = args[:old_username]
  new_username = args[:new_username]
  archetype = args[:archetype]
  archetype = archetype.downcase if archetype

  if !old_username || !new_username
    puts "ERROR: Expecting rake posts:change_post_ownership[old_username,new_username,archetype]"
    exit 1
  end

  old_user = find_user(old_username)
  new_user = find_user(new_username)

  if archetype == "private"
    posts = Post.private_posts.where(user_id: old_user.id)
  elsif archetype == "public" || !archetype
    posts = Post.public_posts.where(user_id: old_user.id)
  else
    puts "ERROR: Expecting rake posts:change_post_ownership[old_username,new_username,archetype] where archetype is public or private"
    exit 1
  end

  puts "Changing post ownership"
  i = 0
  posts.each do |p|
    PostOwnerChanger.new(post_ids: [p.id], topic_id: p.topic.id, new_owner: User.find_by(username_lower: new_user.username_lower), acting_user: User.find_by(username_lower: "system"), skip_revision: true).change_owner!
    putc "."
    i += 1
  end
  puts "", "#{i} posts ownership changed!", ""
end

task "users:merge", [:source_username, :target_username] => [:environment] do |_, args|
  source_username = args[:source_username]
  target_username = args[:target_username]

  if !source_username || !target_username
    puts "ERROR: Expecting rake posts:merge[source_username,target_username]"
    exit 1
  end

  source_user = find_user(source_username)
  target_user = find_user(target_username)

  UserMerger.new(source_user, target_user).merge!
  puts "", "Users merged!", ""
end

task "users:rename", [:old_username, :new_username] => [:environment] do |_, args|
  old_username = args[:old_username]
  new_username = args[:new_username]

  if !old_username || !new_username
    puts "ERROR: Expecting rake posts:rename[old_username,new_username]"
    exit 1
  end

  changer = UsernameChanger.new(find_user(old_username), new_username)
  changer.change(asynchronous: false)
  puts "", "User renamed!", ""
end

def find_user(username)
  user = User.find_by_username(username)

  if !user
    puts "ERROR: User with username #{username} does not exist"
    exit 1
  end

  user
end