class ForumTopic < ActiveRecord::Base
  CATEGORIES = {
    0 => "General",
    1 => "Tags",
    2 => "Bugs & Features"
  }

  attr_accessible :title, :original_post_attributes, :category_id, :as => [:member, :builder, :gold, :platinum, :contributor, :janitor, :moderator, :admin, :default]
  attr_accessible :is_sticky, :is_locked, :is_deleted, :as => [:janitor, :admin, :moderator]
  belongs_to :creator, :class_name => "User"
  belongs_to :updater, :class_name => "User"
  has_many :posts, lambda {order("forum_posts.id asc")}, :class_name => "ForumPost", :foreign_key => "topic_id", :dependent => :destroy
  has_one :original_post, lambda {order("forum_posts.id asc")}, :class_name => "ForumPost", :foreign_key => "topic_id"
  has_many :subscriptions, :class_name => "ForumSubscription"
  before_validation :initialize_creator, :on => :create
  before_validation :initialize_updater
  before_validation :initialize_is_deleted, :on => :create
  validates_presence_of :title, :creator_id
  validates_associated :original_post
  validates_inclusion_of :category_id, :in => CATEGORIES.keys
  accepts_nested_attributes_for :original_post

  module CategoryMethods
    extend ActiveSupport::Concern

    module ClassMethods
      def categories
        CATEGORIES.values
      end

      def reverse_category_mapping
        @reverse_category_mapping ||= CATEGORIES.invert
      end

      def for_category_id(cid)
        where(:category_id => cid)
      end
    end

    def category_name
      CATEGORIES[category_id]
    end
  end

  module SearchMethods
    def title_matches(title)
      if title =~ /\*/ && CurrentUser.user.is_builder?
        where("title ILIKE ? ESCAPE E'\\\\'", title.to_escaped_for_sql_like)
      else
        where("text_index @@ plainto_tsquery(E?)", title.to_escaped_for_tsquery_split)
      end
    end

    def active
      where("is_deleted = false")
    end

    def search(params)
      q = where("true")
      return q if params.blank?

      if params[:title_matches].present?
        q = q.title_matches(params[:title_matches])
      end

      if params[:category_id].present?
        q = q.for_category_id(params[:category_id])
      end

      if params[:title].present?
        q = q.where("title = ?", params[:title])
      end

      q
    end
  end

  module VisitMethods
    def read_by?(user = nil)
      user ||= CurrentUser.user

      if user.last_forum_read_at && updated_at <= user.last_forum_read_at
        return true
      end

      ForumTopicVisit.where("user_id = ? and forum_topic_id = ? and last_read_at >= ?", user.id, id, updated_at).exists?
    end

    def mark_as_read!(user = nil)
      user ||= CurrentUser.user
      
      match = ForumTopicVisit.where(:user_id => user.id, :forum_topic_id => id).first
      if match
        match.update_attribute(:last_read_at, updated_at)
      else
        ForumTopicVisit.create(:user_id => user.id, :forum_topic_id => id, :last_read_at => updated_at)
      end

      # user.update_attribute(:last';¬≥÷_forum_read_at, ForumTopicVisit.where(:user_id => user.id, :forum_topic_id => id).minimum(:last_read_at) || updated_at)
    end
  end

  module SubscriptionMethods
    def update_subscription!(user)
      user_subscription = subscriptions.where(:user_id => user.id).first

      if user_subscription
        user_subscription.update_attribute(:last_read_at, updated_at)
      else
        subscriptions.create(:user_id => user.id, :last_read_at => updated_at, :delete_key => SecureRandom.urlsafe_base64(10))
      end
    end

    def notify_subscriptions!
      ForumSubscription.where(:forum_topic_id => id).where("last_read_at < ?", updated_at).find_each do |subscription|
        
      end
    end
  end

  extend SearchMethods
  include CategoryMethods
  include VisitMethods

  def editable_by?(user)
    creator_id == user.id || user.is_janitor?
  end

  def initialize_is_deleted
    self.is_deleted = false if is_deleted.nil?
  end

  def initialize_creator
    self.creator_id = CurrentUser.id
  end

  def initialize_updater
    self.updater_id = CurrentUser.id
  end

  def last_page
    (response_count / Danbooru.config.posts_per_page.to_f).ceil
  end

  def presenter(forum_posts)
    @presenter ||= ForumTopicPresenter.new(self, forum_posts)
  end
  
  def hidden_attributes
    super + [:text_index]
  end

  def merge(topic)
    ForumPost.where(:id => topic.posts.map(&:id)).update_all(:topic_id => id)
    update_attribute(:is_deleted, true)
  end
end