ruby-rcade/RubyGameDev.com

class Post < ActiveRecord::Base
  belongs_to :user
  has_and_belongs_to_many :tags
  validates :title, presence: true
  after_create :notify_twitter
  after_save :create_tags_from_tag_string
  paginates_per 15

  has_many :votes
  has_many :voted_users, through: :votes, source: :user, class_name: 'User'

  scope :internal_post, -> { where(type: "InternalPost") }
  scope :external_post, -> { where(type: "ExternalPost") }

  def types
    %w(ExternalPost InternalPost)
  end

  def external_post?
    type == "ExternalPost"
  end

  def internal_post?
    type == "InternalPost"
  end

  def username
    logger.error 'Must be implemented by subclass'
    ''
  end

  def number_of_comments
    logger.error 'Must be implemented by subclass'
    0
  end

  def tags_string
    tags.map(&:title).join(", ")
  end

  def tags_string=(value)
    @tags_list = []
    value.strip.downcase.split(/, *| +/).each do |tag|
      @tags_list.push(tag.strip)
    end
    @tags_list = @tags_list.uniq
  end

  # Called after save
  def create_tags_from_tag_string
    return unless @tags_list.present?
    tags.clear
    @tags_list.each do |tag_title|
      existing_tag = Tag.find_by(title: tag_title)

      if existing_tag
        tags << existing_tag
      else
        tags.create!(title: tag_title, user_id: user_id)
      end
    end
  end

  def add_vote(user)
    Vote.find_or_create_by!(post_id: id, user_id: user.id)
  end

  def has_voted?(user)
    Vote.exists?(post_id: id, user_id: user.id)
  end

  def tweet_content
    url = Rails.application.routes.url_helpers.post_short_link_url(self, host: 'rbga.me')
    url = " #{url}"
    max_title_length = 140 - url.length
    title[0...max_title_length] + url
  end

  def notify_twitter
    if Rails.env.production?
      $twitter_client.update(tweet_content)
    end
  end

  def self.search(query)
    sql_query = <<-SQL
      SELECT * FROM posts
      WHERE posts.id IN (
        SELECT DISTINCT p.id
        FROM posts p
        LEFT JOIN comments c ON c.parent_id = p.id
        LEFT JOIN posts_tags pt ON pt.post_id = p.id
        LEFT JOIN tags t ON t.id = pt.tag_id
        WHERE (
              p.title LIKE :query
           OR p.body_markdown LIKE :query
           OR c.body LIKE :query
           OR t.title LIKE :query));
    SQL

    find_by_sql([sql_query, { query: "%#{query}%" }])
  end
end