/artists: sort autocomplete by post count.

* Add search[order]=post_count param to /artists.
* Make autocomplete do a prefix match ordered by post count, so that it
  works the same way that tag autocomplete does elsewhere.

app/assets/javascripts/artists.js

@@ -53,8 +53,9 @@
         $.ajax({
           url: "/artists.json",
           data: {
-            "search[name]": "*" + req.term + "*",
+            "search[name]": req.term + "*",
             "search[is_active]": true,
+            "search[order]": "post_count",
             "limit": 10
           },
           method: "get",

app/controllers/artists_controller.rb

@@ -38,7 +38,7 @@ class ArtistsController < ApplicationController
 
   def index
     search_params = params[:search].present? ? params[:search] : params
-    @artists = Artist.includes(:urls).search(search_params).order("id desc").paginate(params[:page], :limit => params[:limit], :search_count => params[:search])
+    @artists = Artist.includes(:urls).search(search_params).paginate(params[:page], :limit => params[:limit], :search_count => params[:search])
     respond_with(@artists) do |format|
       format.xml do
         render :xml => @artists.to_xml(:include => [:urls], :root => "artists")

app/models/artist.rb

@@ -419,11 +419,13 @@ class Artist < ActiveRecord::Base
       params[:order] ||= params.delete(:sort)
       case params[:order]
       when "name"
-        q = q.reorder("artists.name")
+        q = q.order("artists.name")
       when "updated_at"
-        q = q.reorder("artists.updated_at desc")
+        q = q.order("artists.updated_at desc")
+      when "post_count"
+        q = q.joins(:tag).order("tags.post_count desc")
       else
-        q = q.reorder("artists.id desc")
+        q = q.order("artists.id desc")
       end
 
       if params[:is_active] == "true"

app/views/artists/_search.html.erb

@@ -15,7 +15,7 @@
         <th><label for="search_order">Order</label>
         <td>
           <div class="input">
-            <%= select "search", "order", [["Recently created", "created_at"], ["Last updated", "updated_at"], ["Name", "name"]], :selected => params[:search][:order] %>
+            <%= select "search", "order", [["Recently created", "created_at"], ["Last updated", "updated_at"], ["Name", "name"], ["Post count", "post_count"]], :selected => params[:search][:order] %>
           </div>
         </td>
       </tr>