module Project::HooksTrait
  as_trait do
    def observe_push(oldrev, newrev, ref, user)
      data = post_receive_data(oldrev, newrev, ref, user)

      Event.create(
        :project => self,
        :action => Event::Pushed,
        :data => data,
        :author_id => data[:user_id]
      )
    end

    def update_merge_requests(oldrev, newrev, ref, user)
      return true unless ref =~ /heads/
      branch_name = ref.gsub("refs/heads/", "")
      c_ids = self.commits_between(oldrev, newrev).map(&:id)

      # Update code for merge requests
      mrs = self.merge_requests.opened.find_all_by_branch(branch_name).all
      mrs.each { |merge_request| merge_request.reload_code }

      # Close merge requests
      mrs = self.merge_requests.opened.where(:target_branch => branch_name).all
      mrs = mrs.select(&:last_commit).select { |mr| c_ids.include?(mr.last_commit.id) } 
      mrs.each { |merge_request| merge_request.merge!(user.id) }

      true
    end

    def execute_web_hooks(oldrev, newrev, ref, user)
      ref_parts = ref.split('/')

      # Return if this is not a push to a branch (e.g. new commits)
      return if ref_parts[1] !~ /heads/ || oldrev == "00000000000000000000000000000000"

      data = post_receive_data(oldrev, newrev, ref, user)

      web_hooks.each { |web_hook| web_hook.execute(data) }
    end

    def post_receive_data(oldrev, newrev, ref, user)

      push_commits = commits_between(oldrev, newrev)

      # Total commits count
      push_commits_count = push_commits.size

      # Get latest 20 commits ASC
      push_commits_limited = push_commits.last(20)

      # Hash to be passed as post_receive_data
      data = {
        before: oldrev,
        after: newrev,
        ref: ref,
        user_id: user.id,
        user_name: user.name,
        repository: {
          name: name,
          url: web_url,
          description: description,
          homepage: web_url,
        },
        commits: [],
        total_commits_count: push_commits_count
      }

      # For perfomance purposes maximum 20 latest commits 
      # will be passed as post receive hook data.
      #
      push_commits_limited.each do |commit|
        data[:commits] << {
          id: commit.id,
          message: commit.safe_message,
          timestamp: commit.date.xmlschema,
          url: "http://#{GIT_HOST['host']}/#{code}/commits/#{commit.id}",
          author: {
            name: commit.author_name,
            email: commit.author_email
          }
        }
      end

      data
    end


    # This method will be called after each post receive
    # and only if autor_key_id present in gitlab. 
    # All callbacks for post receive should be placed here
    #
    def trigger_post_receive(oldrev, newrev, ref, author_key_id)
      user = Key.find_by_identifier(author_key_id).user

      # Create push event
      self.observe_push(oldrev, newrev, ref, user)

      # Close merged MR 
      self.update_merge_requests(oldrev, newrev, ref, user)

      # Execute web hooks
      self.execute_web_hooks(oldrev, newrev, ref, user)
    end
  end
end