module ActivoateHelper

  # Get or set the page title
  #
  # title - The title to set. (optional)
  #
  # Example:
  #   page_title("Hello, world!")
  #   # => "Hello, world!"
  #   page_title
  #   # => "Hello, world!"
  #
  # Returns the page title, first setting it if title is not nil.
  def page_title(title = nil)
    @title = title unless title.nil?
    @title
  end

  # Displays a badge
  #
  # content - The bagde`s content
  # color - null for white, or grey, red, yellow, green
  #
  # Example:
  #   <%= badge 'New!', 'yellow' %>
  #
  # Returns a div tag
  def badge(content, color = '')
    color = "-#{color}" unless color.length == 0

    content_tag('div', { :class => "badge#{color}" }) do
      content
    end
  end

  
  # Wraps the button helper, creating an add button
  #
  # path - The button`s action
  #
  # Example:
  #   <%= add_button new_user_path %>
  #
  # Returns an anchor tag
  def add_button(path)
    button(path, t("activoate.add", :default => 'Add'), 'add')
  end
  
  # Wraps the button helper, creating a cancel button
  #
  # path - The button`s action
  #
  # Example:
  #   <%= cancel_button users_path %>
  #
  # Returns an anchor tag
  def cancel_button(path)
    button(path, t("activoate.cancel", :default => 'Cancel'), 'cross')
  end

  # Wraps the button helper, creating an edit button
  #
  # path - The button`s action
  # alternative_icon - True for the alternative icon
  #
  # Example:
  #   <%= edit_button edit_user_path(@user) %>
  #   <%= edit_button edit_user_path(@user), true %>
  #
  # Returns an anchor tag
  def edit_button(path, alternative_icon = false)
    button(path, t("activoate.edit", :default => 'Edit'), alternative_icon ? 'edit' : 'application_edit')
  end

  # Wraps the button helper, creating a delete button
  #
  # path - The button`s action
  # alternative_icon - True for the alternative icon
  #
  # Example:
  #   <%= delete_button users_path(@user) %>
  #   <%= delete_button users_path(@user), true %>
  #
  # Returns an anchor tag
  def delete_button(path, alternative_icon = false)
    options = {
        :confirm => t("activoate.confirm", :default => "Are you sure?"),
        :method => :delete
    }
    button(path, t("activoate.delete", :default => 'Delete'), alternative_icon ? 'delete' : 'cross', options)
  end

  # Displays a button
  #
  # path - The button`s action
  # caption - The button`s caption
  # icon - The icon file name, without the extension
  # options - A hash of attributes to apply to the wrapping anchor tag
  #
  # Example:
  #   <%= button root_path, { :caption => 'home', :icon => 'home' } %>
  #
  # Returns an anchor tag
  def button(path, caption = 'click-me', icon = 'show', options = {})
    default_options = { :class => "button", :confirm => false }
    options = default_options.merge(options)

    link_to path, options do
      image_tag("activo/icons/#{icon}.png", :alt => caption) + " " + caption
    end
  end
  
  # Displays a submit button
  #
  # caption - The button`s caption
  # icon - The icon file name, without the extension
  # options - A hash of attributes to apply to the wrapping button tag
  #
  # Example:
  #   <%= submit_button root_path, { :caption => 'home', :icon => 'home' } %>
  #
  # Returns a button tag
  def submit_button(caption = 'submit', icon = 'show', options = {})
    default_options = { :class => "button", :type => 'submit' }
    options = default_options.merge(options)

    content_tag("button", options) do
      image_tag("activo/icons/#{icon}.png", :alt => caption) + " " + caption
    end
  end

  # Creates a set of buttons
  #
  # options - A hash of attributes to apply to the wrapping div tag
  #
  # Example:
  #   <div class="block">
  #     <div class="content">
  #       <%= controls do |c|
  #         c.item add_button(new_user_path)
  #         c.item button(root_path, { :caption => 'home', :icon => 'home' })
  #         c.item delete_button(users_path(@user), true)
  #       end %>
  #     </div>
  #   </div>
  #
  # Returns a set of controls to be displayed.
  def controls(options = {})
    options[:class] ||= ""
    options[:class] << " control"
    options[:class] = options[:class].strip.html_safe

    items = ControlsBuilder.new
    yield items if block_given?

    content_tag("div", options) do
      items.to_a.join("").html_safe
    end
  end

  # Displays an icon
  #
  # name - The icon file name, without the extension
  # options - A hash of attributes to apply to the image tag
  #
  # Example:
  #   <%= icon 'add', { :alt => "Add item" } %>
  #
  # Returns an img tag.
  def icon(name, options = {})
    return "" if name.nil?

    options[:alt] ||= name.capitalize.gsub("_", " ")

    path = "activo/icons/#{name}.png"

    image_tag path, { :alt => options[:alt] }
  end

  # Displays a navigation menu
  #
  # options - A hash of attributes to apply to the wrapping div tag
  #
  # Example:
  #   <div class="block">
  #     <%= navigation do |nav|
  #       nav.item "List People", people_path, :active => true
  #       nav.item "New Person", new_person_path
  #       nav.item "Search", search_path(:type => "people")
  #     end %>
  #     <div class="content">
  #       <h2 class="title">List People</h2>
  #     </div>
  #   </div>
  #
  # Returns a navigation block to be displayed.
  def navigation(options = {}, &block)
    options[:class] ||= ""
    options[:class] = options[:class].strip.html_safe

    menu = NavigationBuilder.new
    yield menu if block_given?

    content_tag("div", options) do
      content_tag("ul", "", :class => "wat-cf") do
        menu.collect { |item|
          content_tag("li", :class => item[:class]) do
            link_to(item[:label], item[:href], item[:link_options])
          end
        }.join("").html_safe
      end
    end
  end

  # Displays a secondary navigation menu
  def secondary_navigation(options = {}, &block)
    options[:class] ||= ""
    options[:class] << " secondary-navigation"

    navigation(options, &block)
  end

  # Displays a secondary inner navigation menu
  def secondary_inner_navigation(options = {}, &block)
    options[:class] ||= ""
    options[:class] << " secondary-inner-nav"

    navigation(options, &block)
  end

  # Displays a breadcrumb trail
  #
  # options - A hash of attributes to apply to the wrapping div tag
  #
  # Example:
  #   <div class="block">
  #     <div class="content">
  #       <h2><%= @news_item.title %></h2>
  #       <p><%= @news_item.content %></p>
  #     </div>
  #     <%= breadcrumbs do |b|
  #       b.item "Home", root_path
  #       b.item "News", news_path
  #       b.item "Awesome New Things", news_path(@news_item), :active => true
  #     %>
  #   </div>
  #
  # Returns the breadcrumb trail.
  def breadcrumbs(options = {})
    items = NavigationBuilder.new
    yield items if block_given?

    options[:class] ||= ""
    options[:class] << " breadcrumb"
    options[:class] = options[:class].strip.html_safe

    content_tag("div", options) do
      content_tag("ul") do
        items.collect { |item|
          content_tag("li", :class => item[:class]) do
            if item[:active]
              item[:label]
            else
              link_to(item[:label], item[:href])
            end
          end
        }.join("").html_safe
      end
    end
  end

  # Assists in the creation of navigation menus
  class NavigationBuilder
    attr_reader :item_list
    include Enumerable

    def initialize
      @item_list = []
    end

    def each(&blk)
      item_list.each(&blk)
    end

    def item(label, path, options = {})
      options[:class] ||= ""
      options[:class] << " first" if item_list.empty?
      options[:class] << " active" if options[:active]

      options[:link_options] ||= {}
      options[:link_options].merge!(:method => options[:method]) if options[:method]

      item_list << {
        :label => label,
        :href => path,
        :class => options[:class].strip,
        :link_options => options[:link_options],
        :icon => options[:icon],
        :active => !!options[:active]
      }
    end
  end

  # Assists in the creation of control bars
  class ControlsBuilder
    attr_reader :item_list
    include Enumerable

    def initialize
      @item_list = []
    end

    def each(&blk)
      item_list.each(&blk)
    end

    def item(button)
      item_list << button
    end
  end

end