module Spree
  module BaseHelper

    # Defined because Rails' current_page? helper is not working when Spree is mounted at root.
    def current_spree_page?(url)
      path = request.fullpath.gsub(/^\/\//, '/')
      if url.is_a?(String)
        return path == url
      elsif url.is_a?(Hash)
        return path == spree.url_for(url)
      end
      return false
    end

    def link_to_cart(text = nil)
      return "" if current_spree_page?(spree.cart_path)

      text = text ? h(text) : t('cart')
      css_class = nil

      if current_order.nil? or current_order.line_items.empty?
        text = "#{text}: (#{t('empty')})"
        css_class = 'empty'
      else
        text = "#{text}: (#{current_order.item_count})  <span class='amount'>#{current_order.display_total}</span>".html_safe
        css_class = 'full'
      end

      link_to text, spree.cart_path, :class => css_class
    end

    # human readable list of variant options
    def variant_options(v, options={})
      list = v.options_text

      # We shouldn't show out of stock if the product is infact in stock
      # or when we're not allowing backorders.
      unless v.in_stock?
        list = if options[:include_style]
          content_tag(:span, "(#{t(:out_of_stock)}) #{list}", :class => 'out-of-stock')
        else
          "#{t(:out_of_stock)} #{list}"
        end
      end

      list
    end

    def meta_data_tags
      object = instance_variable_get('@'+controller_name.singularize)
      meta = {}

      if object.kind_of? ActiveRecord::Base
        meta[:keywords] = object.meta_keywords if object[:meta_keywords].present?
        meta[:description] = object.meta_description if object[:meta_description].present?
      end

      if meta[:description].blank? && object.kind_of?(Spree::Product)
        meta[:description] = strip_tags(object.description)
      end

      meta.reverse_merge!({
        :keywords => Spree::Config[:default_meta_keywords],
        :description => Spree::Config[:default_meta_description]
      })

      meta.map do |name, content|
        tag('meta', :name => name, :content => content)
      end.join("\n")
    end

    def body_class
      @body_class ||= content_for?(:sidebar) ? 'two-col' : 'one-col'
      @body_class
    end

    def logo(image_path=Spree::Config[:logo])
      link_to image_tag(image_path), root_path
    end

    def flash_messages(opts = {})
      opts[:ignore_types] = [:commerce_tracking].concat(Array(opts[:ignore_types]) || [])

      flash.each do |msg_type, text|
        unless opts[:ignore_types].include?(msg_type)
          concat(content_tag :div, text, :class => "flash #{msg_type}")
        end
      end
      nil
    end

    def breadcrumbs(taxon, separator="&nbsp;&raquo;&nbsp;")
      return "" if current_page?("/") || taxon.nil?
      separator = raw(separator)
      crumbs = [content_tag(:li, link_to(t(:home) , root_path) + separator)]
      if taxon
        crumbs << content_tag(:li, link_to(t(:products) , products_path) + separator)
        crumbs << taxon.ancestors.collect { |ancestor| content_tag(:li, link_to(ancestor.name , seo_url(ancestor)) + separator) } unless taxon.ancestors.empty?
        crumbs << content_tag(:li, content_tag(:span, link_to(taxon.name , seo_url(taxon))))
      else
        crumbs << content_tag(:li, content_tag(:span, t(:products)))
      end
      crumb_list = content_tag(:ul, raw(crumbs.flatten.map{|li| li.mb_chars}.join), :class => 'inline')
      content_tag(:nav, crumb_list, :id => 'breadcrumbs', :class => 'sixteen columns')
    end

    def taxons_tree(root_taxon, current_taxon, max_level = 1)
      return '' if max_level < 1 || root_taxon.children.empty?
      content_tag :ul, :class => 'taxons-list' do
        root_taxon.children.map do |taxon|
          css_class = (current_taxon && current_taxon.self_and_ancestors.include?(taxon)) ? 'current' : nil
          content_tag :li, :class => css_class do
           link_to(taxon.name, seo_url(taxon)) +
           taxons_tree(taxon, current_taxon, max_level - 1)
          end
        end.join("\n").html_safe
      end
    end

    def available_countries
      checkout_zone = Zone.find_by_name(Spree::Config[:checkout_zone])

      if checkout_zone && checkout_zone.kind == 'country'
        countries = checkout_zone.country_list
      else
        countries = Country.all
      end

      countries.collect do |country|
        country.name = I18n.t(country.iso, :scope => 'country_names', :default => country.name)
        country
      end.sort { |a, b| a.name <=> b.name }
    end

    def seo_url(taxon)
      return spree.nested_taxons_path(taxon.permalink)
    end

    def gem_available?(name)
       Gem::Specification.find_by_name(name)
    rescue Gem::LoadError
       false
    rescue
       Gem.available?(name)
    end

    def money(amount)
      ActiveSupport::Deprecation.warn("[SPREE] Spree::BaseHelper#money will be deprecated.  It relies upon a single master currency.  You can instead create a Spree::Money.new(amount, { :currency => your_currency}) or see if the object you're working with returns a Spree::Money object to use.")
      Spree::Money.new(amount)
    end

    def pretty_time(time)
      [I18n.l(time.to_date, :format => :long),
        time.strftime("%H:%m %p")].join(" ")
    end

    def method_missing(method_name, *args, &block)
      if image_style = image_style_from_method_name(method_name)
        define_image_method(image_style)
        self.send(method_name, *args)
      else
        super
      end
    end

    private

    # Returns style of image or nil
    def image_style_from_method_name(method_name)
      if style = method_name.to_s.sub(/_image$/, '')
        possible_styles = Spree::Image.attachment_definitions[:attachment][:styles]
        style if style.in? possible_styles.with_indifferent_access
      end
    end

    def define_image_method(style)
      self.class.send :define_method, "#{style}_image" do |product, *options|
        options = options.first || {}
        if product.images.empty?
          image_tag "noimage/#{style}.png", options
        else
          image = product.images.first
          options.reverse_merge! :alt => image.alt.blank? ? product.name : image.alt
          image_tag image.attachment.url(style), options
        end
      end
    end

  end
end