discourse/app/controllers/topics_controller.rb

require_dependency 'topic_view'
require_dependency 'promotion'

class TopicsController < ApplicationController

  # Avatar is an image request, not XHR
  before_filter :ensure_logged_in, only: [:timings,
                                          :destroy_timings,
                                          :update,
                                          :star,
                                          :destroy,
                                          :status,
                                          :invite,
                                          :mute,
                                          :unmute,
                                          :set_notifications,
                                          :move_posts]
  before_filter :consider_user_for_promotion, only: :show

  skip_before_filter :check_xhr, only: [:avatar, :show]
  caches_action :avatar, :cache_path => Proc.new {|c| "#{c.params[:post_number]}-#{c.params[:topic_id]}" }


  def show
    create_topic_view

    anonymous_etag(@topic_view.topic) do
      redirect_to_correct_topic and return if slugs_do_not_match
      View.create_for(@topic_view.topic, request.remote_ip, current_user)
      track_visit_to_topic
      perform_show_response
    end
  end

  def destroy_timings
    PostTiming.destroy_for(current_user.id, params[:topic_id].to_i)
    render nothing: true
  end

  def update
    topic = Topic.where(id: params[:topic_id]).first
    guardian.ensure_can_edit!(topic)
    topic.title = params[:title] if params[:title].present?

    # TODO: we may need smarter rules about converting archetypes
    if current_user.admin?
      topic.archetype = "regular" if params[:archetype] == 'regular'
    end

    Topic.transaction do
      topic.save
      topic.change_category(params[:category])
    end

    render nothing: true
  end

  def status
    requires_parameters(:status, :enabled)

    raise Discourse::InvalidParameters.new(:status) unless %w(visible closed pinned archived).include?(params[:status])
    @topic = Topic.where(id: params[:topic_id].to_i).first
    guardian.ensure_can_moderate!(@topic)
    @topic.update_status(params[:status], (params[:enabled] == 'true'), current_user)
    render nothing: true
  end

  def star
    @topic = Topic.where(id: params[:topic_id].to_i).first
    guardian.ensure_can_see!(@topic)

    @topic.toggle_star(current_user, params[:starred] == 'true')
    render nothing: true
  end

  def mute
    toggle_mute(true)
  end

  def unmute
    toggle_mute(false)
  end


  def destroy
    topic = Topic.where(id: params[:id]).first
    guardian.ensure_can_delete!(topic)
    topic.destroy
    render nothing: true
  end

  def excerpt
    render nothing: true
  end

  def invite
    requires_parameter(:user)
    topic = Topic.where(id: params[:topic_id]).first
    guardian.ensure_can_invite_to!(topic)

    if topic.invite(current_user, params[:user])
      render json: success_json
    else
      render json: failed_json, status: 422
    end
  end

  def set_notifications
    topic = Topic.find(params[:topic_id].to_i)
    TopicUser.change(current_user, topic.id, notification_level: params[:notification_level].to_i)
    render json: success_json
  end

  def move_posts
    requires_parameters(:title, :post_ids)
    topic = Topic.where(id: params[:topic_id]).first
    guardian.ensure_can_move_posts!(topic)

    # Move the posts
    new_topic = topic.move_posts(current_user, params[:title], params[:post_ids].map {|p| p.to_i})

    if new_topic.present?
      render json: {success: true, url: new_topic.relative_url}
    else
      render json: {success: false}
    end
  end

  def timings
    # TODO: all this should be optimised, tested better

    last_seen_key = "user-last-seen:#{current_user.id}"
    last_seen = $redis.get(last_seen_key)
    if last_seen.present?
      diff = (Time.now.to_f - last_seen.to_f).round
      if diff > 0
        User.update_all ["time_read = time_read + ?", diff], ["id = ? and time_read = ?", current_user.id, current_user.time_read]
      end
    end
    $redis.set(last_seen_key, Time.now.to_f)

    original_unread = current_user.unread_notifications_by_type

    topic_id = params["topic_id"].to_i
    highest_seen = params["highest_seen"].to_i
    added_time = 0


    if params[:timings].present?
      params[:timings].each do |post_number_str, t|
        post_number = post_number_str.to_i

        if post_number >= 0
          if (highest_seen || 0) >= post_number
            Notification.mark_post_read(current_user, topic_id, post_number)
          end

          PostTiming.record_timing(topic_id: topic_id,
                                   post_number: post_number,
                                   user_id: current_user.id,
                                   msecs: t.to_i)
        end
      end
    end

    TopicUser.update_last_read(current_user, topic_id, highest_seen, params[:topic_time].to_i)

    current_user.reload

    if current_user.unread_notifications_by_type != original_unread
      current_user.publish_notifications_state
    end

    render nothing: true
  end

  private

  def create_topic_view
    opts = params.slice(:username_filters, :best_of, :page, :post_number, :posts_before, :posts_after)
    @topic_view = TopicView.new(params[:id] || params[:topic_id], current_user, opts)
  end

  def toggle_mute(v)
    @topic = Topic.where(id: params[:topic_id].to_i).first
    guardian.ensure_can_see!(@topic)

    @topic.toggle_mute(current_user, v)
    render nothing: true
  end

  def consider_user_for_promotion
    Promotion.new(current_user).review if current_user.present?
  end

  def slugs_do_not_match
    params[:slug] && @topic_view.topic.slug != params[:slug]
  end

  def redirect_to_correct_topic
    fullpath = request.fullpath

    split = fullpath.split('/')
    split[2] = @topic_view.topic.slug

    redirect_to split.join('/'), status: 301
  end

  def track_visit_to_topic
    return unless should_track_visit_to_topic?
    TopicUser.track_visit! @topic_view.topic, current_user
    @topic_view.draft = Draft.get(current_user, @topic_view.draft_key, @topic_view.draft_sequence)
  end

  def should_track_visit_to_topic?
    (!request.xhr? || params[:track_visit]) && current_user
  end

  def perform_show_response
    topic_view_serializer = TopicViewSerializer.new(@topic_view, scope: guardian, root: false)
    respond_to do |format|
      format.html do
        store_preloaded("topic_#{@topic_view.topic.id}", MultiJson.dump(topic_view_serializer))
      end

      format.json do
        render_json_dump(topic_view_serializer)
      end
    end
  end
end