# frozen_string_literal: true

module YiffRest
  class APIV2Controller < APIV2::ApplicationController
    include ::ApplicationController::ReadonlyMethods
    before_action :handle_ratelimit, except: %i[robots]
    before_action :validate_images_access, only: %i[index]
    before_action :validate_images_bulk_access, only: %i[bulk]
    before_action -> { track_usage("images") }, only: %i[index categories category image]

    def index
      return render_error(YiffyAPIErrorCodes::IMAGES_IMAGE_RESPONSE_DISABLED, error: "Image response has been disabled. Please use the json response.") if params[:category].ends_with?("/image")

      category = params[:category]&.downcase&.gsub("/", ".") || ""
      category = category[3..] if category.start_with?("v2.")
      return redirect_to("https://yiff.rest") if category.blank?

      limit = params[:amount]&.to_i || 1
      return render_error(YiffyAPIErrorCodes::IMAGES_AMOUNT_LT_ONE, error: "Amount must be 1 or more.") if limit < 1
      return render_error(YiffyAPIErrorCodes::IMAGES_AMOUNT_LT_ONE, error: "Amount must be 5 or less.") if limit > 5

      size_limit = params[:sizeLimit].blank? ? nil : Filesize.from(params[:sizeLimit].to_s).to_i
      return render_error(YiffyAPIErrorCodes::IMAGES_CATEGORY_NOT_FOUND, error: "Category not found.") unless api_categories.include?(category)

      images = APIImage.random(category, limit, size_limit)

      return render_error(YiffyAPIErrorCodes::IMAGES_NO_RESULTS, error: "No results were found. Try changing your search parameters.") if images.empty?

      Cache.redis.multi do |r|
        r.incr("yiffy2:stats:images:#{category}")
        r.incr("yiffy2:stats:images:ip:#{request.remote_ip}")
        r.incr("yiffy2:stats:images:ip:#{request.remote_ip}:#{category}")
        r.incr("yiffy2:stats:images:total")
        r.incr("yiffy2:stats:images:total:#{category}")
        if @apikey.present? && !@apikey&.is_anon?
          r.incr("yiffy2:stats:images:key:#{@apikey.id}")
          r.incr("yiffy2:stats:images:key:#{@apikey.id}:#{category}")
        end
      end

      execute_webhook(category)

      render(json: {
        "$schema": "https://schema.yiff.rest/V2.json",
        images:    images,
        success:   true,
        notes:     notes_for_request,
      })
    end

    def robots
      render(plain: <<~ROBOTS)
        User-agent: *
        Disallow: /
      ROBOTS
    end

    def stats
      render(json: {
        success: true,
        data:    APIKey.stats(ip: request.remote_ip, key: @apikey),
      })
    end

    def categories
      render(json: {
        success: true,
        data:    APIImage.categories,
      })
    end

    def category
      category = params[:category]&.downcase&.gsub("/", ".") || ""
      return render_error(YiffyAPIErrorCodes::IMAGES_CATEGORY_NOT_FOUND, error: "Category not found.") unless api_categories.include?(category)
      count = APIImage.cached_count(category)
      render(json: {
        success: true,
        data:    {
          **APIImage.categories.find { |c| c.db == category }.to_h,
          count: count,
        },
      })
    end

    def image
      image = APIImage.find_by(id: params[:id].gsub("-", ""))
      return render_error(YiffyAPIErrorCodes::IMAGES_NOT_FOUND, error: "Image not found.") unless image
      render(json: {
        success: true,
        data:    {
          **image.as_json,
          category: image.category,
        },
      })
    end

    def bulk
      req = params[:api_v2] || {}
      return render_error(YiffyAPIErrorCodes::BULK_IMAGES_INVALID_BODY, error: "Invalid body, or no categories specified.") if req.blank?
      size_limit = params[:sizeLimit].blank? ? nil : Filesize.from(params[:sizeLimit].to_s).to_i
      total = 0
      valid = true
      req.each do |category, amount|
        total += amount.to_i
        next if api_categories.include?(category)

        render_error(YiffyAPIErrorCodes::IMAGES_CATEGORY_NOT_FOUND, error: "Invalid category specified: #{category}")
        valid = false
        break
      end

      return unless valid
      return render_error(YiffyAPIErrorCodes::BULK_IMAGES_NUMBER_GT_MAX, error: "Total amount of images requested is greater than #{@apikey.bulk_limit} (#{total}).") if total > @apikey.bulk_limit

      images = APIImage.bulk(req, size_limit)

      return render_error(YiffyAPIErrorCodes::IMAGES_NO_RESULTS, error: "No results were found. Try changing your search parameters.") if images.empty?

      Cache.redis.multi do |r|
        r.incrby("yiffy2:stats:images:ip:#{request.remote_ip}", total)
        r.incr("yiffy2:stats:images:ip:#{request.remote_ip}:bulk")
        r.incrby("yiffy2:stats:images:total", total)
        r.incr("yiffy2:stats:images:total:bulk")
        r.incrby("yiffy2:stats:images:key:#{@apikey.id}", total)
        r.incr("yiffy2:stats:images:key:#{@apikey.id}:bulk")
        req.each do |category, amount|
          r.incrby("yiffy2:stats:images:#{category}", amount.to_i)
          r.incr("yiffy2:stats:images:#{category}:bulk")
          r.incrby("yiffy2:stats:images:ip:#{request.remote_ip}:#{category}", amount.to_i)
          r.incr("yiffy2:stats:images:ip:#{request.remote_ip}:#{category}:bulk")
          r.incrby("yiffy2:stats:images:total:#{category}", amount.to_i)
          r.incr("yiffy2:stats:images:total:#{category}:bulk")
          r.incrby("yiffy2:stats:images:key:#{@apikey.id}:#{category}", amount.to_i)
          r.incr("yiffy2:stats:images:key:#{@apikey.id}:#{category}:bulk")
        end
      end

      execute_webhook("bulk", req)

      render(json: {
        success: true,
        data:    images,
      })
    end

    private

    def api_categories
      categories = APIImage.categories.map(&:db)
      [*categories, "chris"] # gay little polar cutie
    end

    def category_info
      [*APIImage.categories, { name: "Gay Polar Cutie", db: "chris", sfw: true }] # gay little polar cutie
    end

    def notes_for_request
      return [] if params[:notes].to_s.downcase == "disabled"
      notes = []
      # notes << { id: 1, content: "This api host (api.furry.bot) is being removed on June 9th, 2021. Please migrate to https://yiff.rest." } if headers["Host"] == "api.furry.bot"
      notes << { id: 2, content: "We've moved to using subdomains for api versioning! e.g. https://v2.yiff.rest. They have the same functionality, just without the version in the path. The /V2 route will not be removed, but v3 and forward will only use the subdomain." } if request.path.start_with?("/V2")
      notes << { id: 3, content: "Hey, we see you aren't using an api key. They're free! To get one, visit https://yiff.rest/apikeys." } if headers["Authorization"].blank?
      # notes << { id: 4, content: "WARNING! This list is STATIC, it can be inaccurate! We recommended parsing the dot notation in https://v2.yiff.rest/categories instead of this!" }
      # notes << { id: 5, content: "Since images are getting bigger, we're adding a size limit parameter. Add ?sizeLimit=<size> to limit the size of images we provide you." } if params[:sizeLimit].blank?
      notes << { id: 6, content: "You can now hide these notes by setting the notes parameter to disabled. (ex: ?notes=disabled)" }
      notes << { id: 7, content: "We now have proper documentation: https://docs.yiff.rest" }
      notes << { id: 8, content: "We have a new service available, a thumbnailer for e621. You can see its documentation at https://docs.yiff.rest/thumbnails." }
    end

    def execute_webhook(category, bulk_categories = nil)
      bulk = ""
      color = 0x008000
      if bulk_categories.present?
        bulk = <<~BULK
          Total: **#{bulk_categories.values.sum}**

          **Categories:**
          #{bulk_categories.permit!.to_h.map { |c, l| "- **#{c}**: #{l}" }.join("\n")}
        BULK
        color = 0xDC143C if bulk_categories.keys.any? { |k| category_info.find { |c| c.db == k }.sfw }
      elsif !category_info.find { |c| c.db == category }.sfw
        color = 0xDC143C
      end
      Websites.config.yiffyapi_usage_webhook.execute(embeds: [
        {
          title:       "V2 API Request",
          description: <<~DESC.strip,
            Host: **#{request.host}**
            Path: **#{request.path}**
            Category: `#{category}`
            Auth: #{@apikey.nil? || @apikey.is_anon? ? '**No**' : "**Yes** (##{@apikey.id})"}
            Size Limit: **#{params[:sizeLimit] || 'None'}**
            User Agent: **#{request.user_agent}**
            IP: **#{request.remote_ip}**
            #{bulk}
          DESC
          color:       color,
          timestamp:   Time.now.iso8601,
        },
      ])
    end

    def allowed_readonly_actions
      super + %w[bulk]
    end
  end
end