tag cloud

git-svn-id: http://svn.barleysodas.com/barleysodas/trunk@46 0f7b21a7-9e3a-4941-bbeb-ce5c7c368fa7

app/controllers/beers_controller.rb

@@ -9,6 +9,10 @@ class BeersController < ApplicationController
     @secondary_title = 'Browsing all beers'
     @pages, @beers = paginate :beers, :include => 'page', :per_page => 50,
       :order => 'beers.title ASC'
+    
+    @tags = Page.tags(:limit => 25, :order => "name DESC",
+      :owner_type => 'Beer')
+    
     respond_to do |format|
       format.html # index.rhtml
       format.xml  { render :xml => @beers.to_xml }

app/controllers/breweries_controller.rb

@@ -9,6 +9,10 @@ class BreweriesController < ApplicationController
     @secondary_title = 'Browsing all breweries'
     @pages, @breweries = paginate :breweries, :include => 'page',
       :order => 'breweries.title ASC', :per_page => 50
+    
+    @tags = Page.tags(:limit => 25, :order => "name DESC",
+      :owner_type => 'Beer')
+    
     respond_to do |format|
       format.html # index.rhtml
       format.xml  { render :xml => @breweries.to_xml }

app/controllers/pages_controller.rb

@@ -15,6 +15,8 @@ class PagesController < ApplicationController
     @pages, @wiki_pages = paginate :page, :per_page => 25,
       :order => 'title ASC', :conditions => [ cond_ary.join(' AND ') ]
     
+    @tags = Page.tags(:limit => 25, :order => "name DESC")
+    
     respond_to do |format|
       format.html # index.rhtml
     end

app/helpers/application_helper.rb

@@ -46,4 +46,26 @@ module ApplicationHelper
   def discussions_allowed?
     @page and @page.allow_discussions?
   end
+  
+  ##
+  # Generates a Tag cloud.
+  #
+  def tag_cloud(tags, classes = tag_cloud_styles)
+    max, min = 0, 0
+    tags.each do |t|
+      max = t.count.to_i if t.count.to_i > max
+      min = t.count.to_i if t.count.to_i < min
+    end
+    divisor = ((max - min) / classes.size) + 1
+    tags.each do |t|
+      yield t.name, classes[(t.count.to_i - min) / divisor]
+    end
+  end
+  
+  ##
+  # Returns an array of Tag styles for a cloud.
+  #
+  def tag_cloud_styles
+    %w(tag_cloud_1 tag_cloud_2 tag_cloud_3 tag_cloud_4 tag_cloud_5)
+  end
 end

app/models/page.rb

@@ -40,6 +40,27 @@ class Page < ActiveRecord::Base
     title.to_s.gsub(/_/, ' ')
   end
   
+  ##
+  # Returns a list of Tag models for a type of Page.
+  #
+  # Can take options of :order, :limit, and :owner_type
+  #
+  def self.tags(options = {})
+    query = "select tags.id, name, count(*) as count"
+    query << " from tags_pages, tags, pages"
+    query << " where tags.id = tag_id"
+    if options[:owner_type].nil?
+      query << " and pages.owner_type IS NULL"
+    else
+      query << " and pages.owner_type = '#{options[:owner_type]}'"
+    end
+    query << " and tags_pages.page_id = pages.id"
+    query << " group by tags.id, tags.name"
+    query << " order by #{options[:order]}" if options[:order] != nil
+    query << " limit #{options[:limit]}" if options[:limit] != nil
+    tags = Tag.find_by_sql(query)
+  end
+  
   protected
   
   ##

app/views/beers/index.rhtml

@@ -20,4 +20,5 @@
 
 <% content_for :sidebar do -%>
   <%= link_to "New Beer", new_beer_path, { :title => 'Create a new beer' } -%><br />
+  <%= render :partial => 'shared/tag_cloud' %>
 <% end -%>

app/views/breweries/index.rhtml

@@ -21,4 +21,5 @@
 
 <% content_for :sidebar do -%>
   <%= link_to 'New brewery', new_brewery_path -%><br />
+  <%= render :partial => 'shared/tag_cloud' %>
 <% end -%>

app/views/pages/index.rhtml

@@ -11,4 +11,5 @@
 
 <% content_for :sidebar do -%>
   <%= new_page_link -%><br />
+  <%= render :partial => 'shared/tag_cloud' %>
 <% end -%>

app/views/shared/_tag_cloud.rhtml

@@ -0,0 +1,9 @@
+<% unless @tags.empty? -%>
+<div id="tag_cloud">
+<hr />
+<p>Tag Cloud</p>
+<% tag_cloud @tags, tag_cloud_styles do |name, css_class| %>
+  <span class="<%= css_class -%>"><%= name -%></span>
+<% end %>
+</div>
+<% end -%>

public/stylesheets/content.css

@@ -398,3 +398,19 @@
   margin: 0; padding: 0 0 0 1em;
   display: inline; 
 }
+
+/* Tag Cloud Styles */
+.tag_cloud_1 {font-size: 1.0em;}
+.tag_cloud_2 {font-size: 1.2em;}
+.tag_cloud_3 {font-size: 1.4em;}
+.tag_cloud_4 {font-size: 1.6em;}
+.tag_cloud_5 {font-size: 1.8em;}
+.tag_cloud_6 {font-size: 2.0em;}
+
+#tag_cloud p {
+  text-align: center;
+  margin: 0px;
+  padding: 0px;
+  font-size: 1.1em;
+  font-weight: bold;
+}