rearrange plugin modules so not all AR models contain the custom perm…

…alink options

lib/permalink_fu.rb

@@ -9,27 +9,24 @@ module PermalinkFu
   class << self
     attr_accessor :translation_to
     attr_accessor :translation_from
-
+
+    # This method does the actual permalink escaping.
     def escape(str)
       s = ((translation_to && translation_from) ? Iconv.iconv(translation_to, translation_from, str) : str).to_s
       s.gsub!(/[^\w -]+/, '') # strip unwanted characters
-      s.strip!            # ohh la la
-      s.downcase!         #
-      s.gsub!(/[ -]+/, '-') # separate by single dashes
+      s.strip!                # ohh la la
+      s.downcase!             #
+      s.gsub!(/[ -]+/, '-')   # separate by single dashes
       s
     end
   end
 
   def self.included(base)
-    base.extend ClassMethods
-    class << base
-      attr_accessor :permalink_options
-      attr_accessor :permalink_attributes
-      attr_accessor :permalink_field
-    end
+    base.extend PluginMethods
   end
-
-  module ClassMethods
+
+  # This is the plugin method available on all ActiveRecord models.
+  module PluginMethods
     # Specifies the given field(s) as a permalink, meaning it is passed through PermalinkFu.escape and set to the permalink_field.  This
     # is done
     #
@@ -56,67 +53,88 @@ def has_permalink(attr_names = [], permalink_field = nil, options = {})
         options = permalink_field
         permalink_field = nil
       end
+      extend ClassMethods
       self.permalink_attributes = Array(attr_names)
       self.permalink_field      = (permalink_field || 'permalink').to_s
       self.permalink_options    = options
-      before_validation :create_unique_permalink
-      evaluate_attribute_method permalink_field, "def #{self.permalink_field}=(new_value);write_attribute(:#{self.permalink_field}, PermalinkFu.escape(new_value));end", "#{self.permalink_field}="
+      setup_permalink_fu
     end
   end
-
-protected
-  def create_unique_permalink
-    return unless should_create_permalink?
-    if send(self.class.permalink_field).to_s.empty?
-      send("#{self.class.permalink_field}=", create_permalink_for(self.class.permalink_attributes))
-    end
-    limit   = self.class.columns_hash[self.class.permalink_field].limit
-    base    = send("#{self.class.permalink_field}=", send(self.class.permalink_field)[0..limit - 1])
-    counter = 1
-    # oh how i wish i could use a hash for conditions
-    conditions = ["#{self.class.permalink_field} = ?", base]
-    unless new_record?
-      conditions.first << " and id != ?"
-      conditions       << id
-    end
-    if self.class.permalink_options[:scope]
-      scopes = [self.class.permalink_options[:scope]]
-      scopes.flatten!
-      scopes.each do |scope|
-        conditions.first << " and #{scope} = ?"
-        conditions       << send(scope)
+
+  # Contains class methods for ActiveRecord models that have permalinks
+  module ClassMethods
+    def self.extended(base)
+      class << base
+        attr_accessor :permalink_options
+        attr_accessor :permalink_attributes
+        attr_accessor :permalink_field
       end
+      base.send :include, InstanceMethods
     end
-    while self.class.exists?(conditions)
-      suffix = "-#{counter += 1}"
-      conditions[1] = "#{base[0..limit-suffix.size-1]}#{suffix}"
-      send("#{self.class.permalink_field}=", conditions[1])
+
+  protected
+    def setup_permalink_fu
+      before_validation :create_unique_permalink
+      evaluate_attribute_method permalink_field, "def #{self.permalink_field}=(new_value);write_attribute(:#{self.permalink_field}, PermalinkFu.escape(new_value));end", "#{self.permalink_field}="
     end
   end
 
-  def create_permalink_for(attr_names)
-    attr_names.collect { |attr_name| send(attr_name).to_s } * " "
-  end
+  # This contains instance methods for ActiveRecord models that have permalinks.
+  module InstanceMethods
+  protected
+    def create_unique_permalink
+      return unless should_create_permalink?
+      if send(self.class.permalink_field).to_s.empty?
+        send("#{self.class.permalink_field}=", create_permalink_for(self.class.permalink_attributes))
+      end
+      limit   = self.class.columns_hash[self.class.permalink_field].limit
+      base    = send("#{self.class.permalink_field}=", send(self.class.permalink_field)[0..limit - 1])
+      counter = 1
+      # oh how i wish i could use a hash for conditions
+      conditions = ["#{self.class.permalink_field} = ?", base]
+      unless new_record?
+        conditions.first << " and id != ?"
+        conditions       << id
+      end
+      if self.class.permalink_options[:scope]
+        scopes = [self.class.permalink_options[:scope]]
+        scopes.flatten!
+        scopes.each do |scope|
+          conditions.first << " and #{scope} = ?"
+          conditions       << send(scope)
+        end
+      end
+      while self.class.exists?(conditions)
+        suffix = "-#{counter += 1}"
+        conditions[1] = "#{base[0..limit-suffix.size-1]}#{suffix}"
+        send("#{self.class.permalink_field}=", conditions[1])
+      end
+    end
 
-private
-  def should_create_permalink?
-    if self.class.permalink_options[:if]
-      evaluate_method(self.class.permalink_options[:if])
-    elsif self.class.permalink_options[:unless]
-      !evaluate_method(self.class.permalink_options[:unless])
-    else
-      true
+    def create_permalink_for(attr_names)
+      attr_names.collect { |attr_name| send(attr_name).to_s } * " "
+    end
+
+  private
+    def should_create_permalink?
+      if self.class.permalink_options[:if]
+        evaluate_method(self.class.permalink_options[:if])
+      elsif self.class.permalink_options[:unless]
+        !evaluate_method(self.class.permalink_options[:unless])
+      else
+        true
+      end
     end
-  end
 
-  def evaluate_method(method)
-    case method
-    when Symbol
-      send(method)
-    when String
-      eval(method, instance_eval { binding })
-    when Proc, Method
-      method.call(self)
+    def evaluate_method(method)
+      case method
+      when Symbol
+        send(method)
+      when String
+        eval(method, instance_eval { binding })
+      when Proc, Method
+        method.call(self)
+      end
     end
   end
 end