# frozen_string_literal: true

class Api::V1::Timelines::ExploreController < Api::BaseController
  before_action :set_sort_type
  before_action :set_statuses

  after_action :insert_pagination_headers, unless: -> { @statuses.empty? }

  def show
    if current_user
      render json: @statuses,
            each_serializer: REST::StatusSerializer,
            relationships: StatusRelationshipsPresenter.new(@statuses, current_user.account_id)
    else
      render json: @statuses, each_serializer: REST::StatusSerializer
    end
  end

  private

  def set_sort_type
    @sort_type = 'newest'
    @sort_type = params[:sort_by] if [
      'hot',
      'newest',
      'recent',
      'top_today',
      'top_weekly',
      'top_monthly',
      'top_yearly',
      'top_all_time',
    ].include? params[:sort_by]

    return @sort_type
  end

  def set_statuses
    @statuses = cached_explore_statuses
  end

  def cached_explore_statuses
    cache_collection explore_statuses, Status
  end

  def explore_statuses
    if current_account
      SortingQueryBuilder.new.call(@sort_type, nil, params[:page], nil, "explore").reject {|status|
        FeedManager.instance.filter?(:home, status, current_account.id)
      }
    else
      page = [params[:page].to_i.abs, MIN_UNAUTHENTICATED_PAGES].min
      SortingQueryBuilder.new.call(@sort_type, nil, page, nil, "explore")
    end
  end

  def insert_pagination_headers
    set_pagination_headers(next_path, prev_path)
  end

  def pagination_params(core_params)
    params.slice(:limit).permit(:limit).merge(core_params)
  end

  def next_path
    api_v1_timelines_explore_url params[:id], pagination_params(max_id: pagination_max_id)
  end

  def prev_path
    api_v1_timelines_explore_url params[:id], pagination_params(min_id: pagination_since_id)
  end

  def pagination_max_id
    @statuses.last.id
  end

  def pagination_since_id
    @statuses.first.id
  end
end