Chris@909: module ActionView
Chris@909:   module Helpers
Chris@909:     # Provides methods for linking to ActionController::Pagination objects using a simple generator API.  You can optionally
Chris@909:     # also build your links manually using ActionView::Helpers::AssetHelper#link_to like so:
Chris@909:     #
Chris@909:     # <%= link_to "Previous page", { :page => paginator.current.previous } if paginator.current.previous %>
Chris@909:     # <%= link_to "Next page", { :page => paginator.current.next } if paginator.current.next %>
Chris@909:     module PaginationHelper
Chris@909:       unless const_defined?(:DEFAULT_OPTIONS)
Chris@909:         DEFAULT_OPTIONS = {
Chris@909:           :name => :page,
Chris@909:           :window_size => 2,
Chris@909:           :always_show_anchors => true,
Chris@909:           :link_to_current_page => false,
Chris@909:           :params => {}
Chris@909:         }
Chris@909:       end
Chris@909: 
Chris@909:       # Creates a basic HTML link bar for the given +paginator+.  Links will be created
Chris@909:       # for the next and/or previous page and for a number of other pages around the current
Chris@909:       # pages position. The +html_options+ hash is passed to +link_to+ when the links are created.
Chris@909:       #
Chris@909:       # ==== Options
Chris@909:       # <tt>:name</tt>::                 the routing name for this paginator
Chris@909:       #                                  (defaults to +page+)
Chris@909:       # <tt>:prefix</tt>::               prefix for pagination links
Chris@909:       #                                  (i.e. Older Pages: 1 2 3 4)
Chris@909:       # <tt>:suffix</tt>::               suffix for pagination links
Chris@909:       #                                  (i.e. 1 2 3 4 <- Older Pages)
Chris@909:       # <tt>:window_size</tt>::          the number of pages to show around 
Chris@909:       #                                  the current page (defaults to <tt>2</tt>)
Chris@909:       # <tt>:always_show_anchors</tt>::  whether or not the first and last
Chris@909:       #                                  pages should always be shown
Chris@909:       #                                  (defaults to +true+)
Chris@909:       # <tt>:link_to_current_page</tt>:: whether or not the current page
Chris@909:       #                                  should be linked to (defaults to
Chris@909:       #                                  +false+)
Chris@909:       # <tt>:params</tt>::               any additional routing parameters
Chris@909:       #                                  for page URLs
Chris@909:       #
Chris@909:       # ==== Examples
Chris@909:       #  # We'll assume we have a paginator setup in @person_pages...
Chris@909:       #
Chris@909:       #  pagination_links(@person_pages)
Chris@909:       #  # => 1 <a href="/?page=2/">2</a> <a href="/?page=3/">3</a>  ... <a href="/?page=10/">10</a>
Chris@909:       #
Chris@909:       #  pagination_links(@person_pages, :link_to_current_page => true)
Chris@909:       #  # => <a href="/?page=1/">1</a> <a href="/?page=2/">2</a> <a href="/?page=3/">3</a>  ... <a href="/?page=10/">10</a>
Chris@909:       #
Chris@909:       #  pagination_links(@person_pages, :always_show_anchors => false)
Chris@909:       #  # => 1 <a href="/?page=2/">2</a> <a href="/?page=3/">3</a> 
Chris@909:       #
Chris@909:       #  pagination_links(@person_pages, :window_size => 1)
Chris@909:       #  # => 1 <a href="/?page=2/">2</a>  ... <a href="/?page=10/">10</a>
Chris@909:       #
Chris@909:       #  pagination_links(@person_pages, :params => { :viewer => "flash" })
Chris@909:       #  # => 1 <a href="/?page=2&amp;viewer=flash/">2</a> <a href="/?page=3&amp;viewer=flash/">3</a>  ... 
Chris@909:       #  #    <a href="/?page=10&amp;viewer=flash/">10</a>
Chris@909:       def pagination_links(paginator, options={}, html_options={})
Chris@909:         name = options[:name] || DEFAULT_OPTIONS[:name]
Chris@909:         params = (options[:params] || DEFAULT_OPTIONS[:params]).clone
Chris@909:         
Chris@909:         prefix = options[:prefix] || ''
Chris@909:         suffix = options[:suffix] || ''
Chris@909: 
Chris@909:         pagination_links_each(paginator, options, prefix, suffix) do |n|
Chris@909:           params[name] = n
Chris@909:           link_to(n.to_s, params, html_options)
Chris@909:         end
Chris@909:       end
Chris@909: 
Chris@909:       # Iterate through the pages of a given +paginator+, invoking a
Chris@909:       # block for each page number that needs to be rendered as a link.
Chris@909:       # 
Chris@909:       # ==== Options
Chris@909:       # <tt>:window_size</tt>::          the number of pages to show around 
Chris@909:       #                                  the current page (defaults to +2+)
Chris@909:       # <tt>:always_show_anchors</tt>::  whether or not the first and last
Chris@909:       #                                  pages should always be shown
Chris@909:       #                                  (defaults to +true+)
Chris@909:       # <tt>:link_to_current_page</tt>:: whether or not the current page
Chris@909:       #                                  should be linked to (defaults to
Chris@909:       #                                  +false+)
Chris@909:       #
Chris@909:       # ==== Example
Chris@909:       #  # Turn paginated links into an Ajax call
Chris@909:       #  pagination_links_each(paginator, page_options) do |link|
Chris@909:       #    options = { :url => {:action => 'list'}, :update => 'results' }
Chris@909:       #    html_options = { :href => url_for(:action => 'list') }
Chris@909:       #
Chris@909:       #    link_to_remote(link.to_s, options, html_options)
Chris@909:       #  end
Chris@909:       def pagination_links_each(paginator, options, prefix = nil, suffix = nil)
Chris@909:         options = DEFAULT_OPTIONS.merge(options)
Chris@909:         link_to_current_page = options[:link_to_current_page]
Chris@909:         always_show_anchors = options[:always_show_anchors]
Chris@909: 
Chris@909:         current_page = paginator.current_page
Chris@909:         window_pages = current_page.window(options[:window_size]).pages
Chris@909:         return if window_pages.length <= 1 unless link_to_current_page
Chris@909:         
Chris@909:         first, last = paginator.first, paginator.last
Chris@909:         
Chris@909:         html = ''
Chris@909: 
Chris@909:         html << prefix if prefix
Chris@909: 
Chris@909:         if always_show_anchors and not (wp_first = window_pages[0]).first?
Chris@909:           html << yield(first.number)
Chris@909:           html << ' ... ' if wp_first.number - first.number > 1
Chris@909:           html << ' '
Chris@909:         end
Chris@909:           
Chris@909:         window_pages.each do |page|
Chris@909:           if current_page == page && !link_to_current_page
Chris@909:             html << page.number.to_s
Chris@909:           else
Chris@909:             html << yield(page.number)
Chris@909:           end
Chris@909:           html << ' '
Chris@909:         end
Chris@909:         
Chris@909:         if always_show_anchors and not (wp_last = window_pages[-1]).last? 
Chris@909:           html << ' ... ' if last.number - wp_last.number > 1
Chris@909:           html << yield(last.number)
Chris@909:         end
Chris@909: 
Chris@909:         html << suffix if suffix
Chris@909: 
Chris@909:         html
Chris@909:       end
Chris@909:       
Chris@909:     end # PaginationHelper
Chris@909:   end # Helpers
Chris@909: end # ActionView