module Alchemy
  # Renders an essence picture view
  class EssencePictureView
    include ActionView::Helpers::AssetTagHelper
    include ActionView::Helpers::UrlHelper
    include Rails.application.routes.url_helpers

    attr_reader :content, :essence, :html_options, :options, :picture

    DEFAULT_OPTIONS = {
      show_caption: true,
      disable_link: false,
      srcset: [],
      sizes: []
    }

    def initialize(content, options = {}, html_options = {})
      @content = content
      @options = DEFAULT_OPTIONS.merge(content.settings).merge(options)
      if @options[:image_size].present?
        ActiveSupport::Deprecation.warn(
          "Passing `image_size` to EssencePicture is deprecated. Please use `size` instead.",
          caller.unshift
        )
        @options[:size] = @options.delete(:image_size)
      end
      @html_options = html_options
      @essence = content.essence
      @picture = essence.picture
    end

    def render
      return if picture.blank?

      output = caption ? img_tag + caption : img_tag

      if is_linked?
        output = link_to(output, url_for(essence.link), {
          title: essence.link_title.presence,
          target: essence.link_target == "blank" ? "_blank" : nil,
          data: {link_target: essence.link_target.presence}
        })
      end

      if caption
        content_tag(:figure, output, {class: essence.css_class.presence}.merge(html_options))
      else
        output
      end
    end

    private

    def caption
      return unless show_caption?
      @_caption ||= content_tag(:figcaption, essence.caption)
    end

    def img_tag
      @_img_tag ||= image_tag(
        essence.picture_url(options.except(*DEFAULT_OPTIONS.keys)), {
          alt: essence.alt_tag.presence,
          title: essence.title.presence,
          class: caption ? nil : essence.css_class.presence,
          srcset: srcset.join(', ').presence,
          sizes: options[:sizes].join(', ').presence
        }.merge(caption ? {} : html_options)
      )
    end

    def show_caption?
      options[:show_caption] && essence.caption.present?
    end

    def is_linked?
      !options[:disable_link] && essence.link.present?
    end

    def srcset
      options[:srcset].map do |size|
        url = essence.picture_url(size: size)
        width, height = size.split('x')
        width.present? ? "#{url} #{width}w" : "#{url} #{height}h"
      end
    end
  end
end