add a navigation manager. closes #59

CHANGELOG.md

@@ -6,6 +6,10 @@ This document outlines key changes which are introduced in each version. The ful
 
 * Add an admin-side order form for adding new orders and editing existing orders
 
+* Adds `Shoppe::NavigationManager` which is used for managing sets of navigation within
+  the Shoppe interface. This allows module developers to add their own when appropriate
+  without needing to hack it into the view.
+
 ## v0.0.19
 
 * Only check that a delivery service is suitable if one has actually been selected. Ensures that

app/helpers/shoppe/application_helper.rb

@@ -1,5 +1,9 @@
 module Shoppe
   module ApplicationHelper
+
+    def navigation_manager_link(item)
+      link_to item.description, item.url, item.link_options.merge(:class => item.active?(self) ? 'active' : 'inactive')
+    end
 
     def status_tag(status)
       content_tag :span, status, :class => "status-tag #{status}"

app/views/layouts/shoppe/application.html.haml

@@ -16,16 +16,19 @@
       %p.logged
         Logged in as #{current_user.full_name}
       %ul
-        %li
-          %span.pending= Shoppe::Order.pending.count
-          = link_to "Orders", [:orders], :class => @active_nav == :orders ? 'active' : ''
-        %li= link_to "Products", [:products], :class => @active_nav == :products ? 'active' : ''
-        %li= link_to "Product Categories", :product_categories, :class => @active_nav == :product_categories ? 'active' : ''
-        %li= link_to "Delivery Services", [:delivery_services], :class => @active_nav == :delivery_services ? 'active' : ''
-        %li= link_to "Tax Rates", :tax_rates, :class => @active_nav == :tax_rates ? 'active' : ''
-        %li= link_to "Users", [:users], :class => @active_nav == :users ? 'active' : ''
-        %li= link_to "Countries", :countries, :class => @active_nav == :countries ? 'active' : ''
-        %li= link_to "Settings", :settings, :class => @active_nav == :settings ? 'active' : ''
+        - for item in Shoppe::NavigationManager.find(:admin_primary).items
+          %li= navigation_manager_link item
+
+        -#%li
+        -#  %span.pending= Shoppe::Order.pending.count
+        -#  = link_to "Orders", [:orders], :class => @active_nav == :orders ? 'active' : ''
+        -#%li= link_to "Products", [:products], :class => @active_nav == :products ? 'active' : ''
+        -#%li= link_to "Product Categories", :product_categories, :class => @active_nav == :product_categories ? 'active' : ''
+        -#%li= link_to "Delivery Services", [:delivery_services], :class => @active_nav == :delivery_services ? 'active' : ''
+        -#%li= link_to "Tax Rates", :tax_rates, :class => @active_nav == :tax_rates ? 'active' : ''
+        -#%li= link_to "Users", [:users], :class => @active_nav == :users ? 'active' : ''
+        -#%li= link_to "Countries", :countries, :class => @active_nav == :countries ? 'active' : ''
+        -#%li= link_to "Settings", :settings, :class => @active_nav == :settings ? 'active' : ''
         %li= link_to "Logout", [:logout], :method => :delete
 
     %header.main

config/locales/en.yml

@@ -1,6 +1,16 @@
 en:
   shoppe:
 
+    navigation:
+      admin_primary:
+        orders: Orders
+        products: Products
+        product_categories: Product Categories
+        delivery_services: Delivery Services
+        tax_rates: Tax Rates
+        users: Users
+        countries: Countries
+
     settings:
 
       types:

lib/shoppe/default_navigation.rb

@@ -0,0 +1,19 @@
+require 'shoppe/navigation_manager'
+
+# This file defines all the default navigation managers used in Shoppe. Of course,
+# modules can make changes to these by removing them or adding their own. This
+# file is loaded on application initialization so if you make changes, you'll need
+# to restart the webserver.
+
+#
+# This is the default navigation manager for the admin interface. 
+#
+Shoppe::NavigationManager.build(:admin_primary) do
+  add_item :orders
+  add_item :products
+  add_item :product_categories
+  add_item :delivery_services
+  add_item :tax_rates
+  add_item :users
+  add_item :countries
+end

lib/shoppe/engine.rb

@@ -28,13 +28,16 @@ class Engine < ::Rails::Engine
         config.paths["db/migrate"].expanded.each do |expanded_path|
           app.config.paths["db/migrate"] << expanded_path
         end
-      end
+      end      
 
       # Load view helpers for the base application
       ActiveSupport.on_load(:action_view) do
         require 'shoppe/view_helpers'
         ActionView::Base.send :include, Shoppe::ViewHelpers
       end
+
+      # Load default navigation
+      require 'shoppe/default_navigation'
     end
 
     generators do
@@ -43,3 +46,4 @@ class Engine < ::Rails::Engine
 
   end
 end
+

lib/shoppe/navigation_manager.rb

@@ -0,0 +1,79 @@
+module Shoppe
+  class NavigationManager
+
+    def self.managers
+      @managers ||= []
+    end
+
+    def self.create(identifier)
+      managers << self.new(identifier.to_s)
+    end
+
+    def self.build(identifier, &block)
+      manager = self.new(identifier.to_s)
+      manager.instance_eval(&block) if block_given?
+      managers << manager
+    end
+
+    def self.find(identifier)
+      managers.select { |m| m.identifier == identifier.to_s }.first
+    end
+
+    def self.render(identifier)
+      find(identifier).try(:to_html)
+    end
+
+    attr_reader :identifier
+
+    def initialize(identifier)
+      @identifier = identifier
+    end
+
+    def items
+      @items ||= []
+    end
+
+    def add_item(identifier, options = {}, &block)
+      item                  = NavigationItem.new
+      item.manager          = self
+      item.identifier       = identifier.to_s
+      item.url              = options[:url]             if options[:url]
+      item.link_options     = options[:link_options]    if options[:link_options]
+      item.active_if        = block                     if block_given?
+      items << item
+    end
+
+    def remove_item(identifier)
+      items.remote_if { |i| i.identifier.to_s == identifier.to_s }
+    end
+
+    class NavigationItem
+      attr_accessor :manager
+      attr_accessor :identifier
+      attr_accessor :url
+      attr_accessor :link_options
+      attr_accessor :active_if
+
+      def description
+        I18n.translate("shoppe.navigation.#{manager.identifier}.#{identifier}")
+      end
+
+      def url
+        @url || Shoppe::Engine.routes.url_helpers.send("#{identifier}_path")
+      end
+
+      def active?(request)
+        if active_if.is_a?(Proc)
+          active_if.call(request) == true
+        elsif active_nav_var = request.instance_variable_get('@active_nav')
+          active_nav_var.to_s == identifier
+        end
+      end
+
+      def link_options
+        @link_options ||= {}
+      end
+    end
+
+  end
+end