cleanup

5 files changed, 120 insertions, 15 deletions

diff --git a/lib/arel/primitives/expression.rb b/lib/arel/primitives/expression.rb
index bf674cc9e1..75bf1f2ef0 100644
--- a/lib/arel/primitives/expression.rb
+++ b/lib/arel/primitives/expression.rb
@@ -1,7 +1,5 @@
 module Arel
   class Expression < Attribute
-    include Sql::Quoting
-    
     attr_reader :attribute, :function_sql
     delegate :relation, :to => :attribute
     alias_method :name, :alias
@@ -25,8 +23,8 @@ module Arel
     end
     include Transformations
     
-    def to_sql(formatter = nil)
-      "#{function_sql}(#{attribute.to_sql})" + (@alias ? " AS #{quote_column_name(@alias)}" : '')
+    def to_sql(formatter = Sql::SelectClause.new(relation))
+      formatter.expression self
     end
     
     def aggregation?
diff --git a/lib/arel/relations/join.rb b/lib/arel/relations/join.rb
index 0dec80af79..a30c179e4e 100644
--- a/lib/arel/relations/join.rb
+++ b/lib/arel/relations/join.rb
@@ -30,7 +30,7 @@ module Arel
           relation2.table.table_sql(formatter)
         end,
         ("ON" unless predicates.blank?),
-        predicates.collect { |p| p.bind(formatter.christener).to_sql }.join(' AND ')
+        predicates.collect { |p| p.bind(formatter.environment).to_sql }.join(' AND ')
       ].compact.join(" ")
       [relation1.joins(formatter), this_join, relation2.joins(formatter)].compact.join(" ")
     end
@@ -39,15 +39,6 @@ module Arel
       (externalize(relation1).selects + externalize(relation2).selects).collect { |s| s.bind(self) }
     end
    
-    def name_for(relation)
-      @used_names ||= Hash.new(0)
-      @relation_names ||= Hash.new do |h, k|
-        @used_names[k.name] += 1
-        h[k] = k.name + (@used_names[k.name] > 1 ? "_#{@used_names[k.name]}" : '')
-      end
-      @relation_names[relation]
-    end
-    
     def table
       relation1.aggregation?? relation1 : relation1.table
     end
diff --git a/lib/arel/relations/relation.rb b/lib/arel/relations/relation.rb
index 336960f424..0b20985914 100644
--- a/lib/arel/relations/relation.rb
+++ b/lib/arel/relations/relation.rb
@@ -159,7 +159,7 @@ module Arel
     end
     
     def christener
-      self
+      @christener ||= Sql::Christener.new
     end
 
     def attributes;  []  end
diff --git a/lib/arel/sql/christener.rb b/lib/arel/sql/christener.rb
new file mode 100644
index 0000000000..894f030342
--- /dev/null
+++ b/lib/arel/sql/christener.rb
@@ -0,0 +1,14 @@
+module Arel
+  module Sql
+    class Christener
+      def name_for(relation)
+        @used_names ||= Hash.new(0)
+        @relation_names ||= Hash.new do |h, k|
+          @used_names[k.name] += 1
+          h[k] = k.name + (@used_names[k.name] > 1 ? "_#{@used_names[k.name]}" : '')
+        end
+        @relation_names[relation]
+      end
+    end
+  end
+end
\ No newline at end of file
diff --git a/lib/arel/sql/formatters.rb b/lib/arel/sql/formatters.rb
new file mode 100644
index 0000000000..96bab2495c
--- /dev/null
+++ b/lib/arel/sql/formatters.rb
@@ -0,0 +1,102 @@
+module Arel
+  module Sql
+    class Formatter
+      attr_reader :environment
+      delegate :christener, :engine, :to => :environment
+      delegate :name_for, :to => :christener
+      delegate :quote_table_name, :quote_column_name, :quote, :to => :engine
+      
+      def initialize(environment)
+        @environment = environment
+      end
+    end
+    
+    class SelectClause < Formatter
+      def attribute(attribute)
+        "#{quote_table_name(name_for(attribute.original_relation))}.#{quote_column_name(attribute.name)}" + (attribute.alias ? " AS #{quote(attribute.alias.to_s)}" : "")
+      end
+      
+      def expression(expression)
+        "#{expression.function_sql}(#{expression.attribute.to_sql(self)})" + (expression.alias ? " AS #{quote_column_name(expression.alias)}" : '')
+      end
+      
+      def select(select_sql, name)
+        "(#{select_sql}) AS #{quote_table_name(name.to_s)}"
+      end
+      
+      def value(value)
+        value
+      end
+    end
+    
+    class PassThrough < Formatter
+      def value(value)
+        value
+      end
+    end
+    
+    class WhereClause < PassThrough
+    end
+    
+    class OrderClause < PassThrough      
+      def attribute(attribute)
+        "#{quote_table_name(name_for(attribute.original_relation))}.#{quote_column_name(attribute.name)}"
+      end
+    end
+    
+    class WhereCondition < Formatter
+      def attribute(attribute)
+        "#{quote_table_name(name_for(attribute.original_relation))}.#{quote_column_name(attribute.name)}"
+      end
+      
+      def expression(expression)
+        "#{expression.function_sql}(#{expression.attribute.to_sql(self)})"
+      end
+      
+      def value(value)
+        value.to_sql(self)
+      end
+      
+      def scalar(value, column = nil)
+        quote(value, column)
+      end
+      
+      def select(select_sql, name)
+        "(#{select_sql})"
+      end
+    end
+    
+    class SelectStatement < Formatter
+      def select(select_sql, name)
+        select_sql
+      end
+    end
+    
+    class TableReference < Formatter
+      def select(select_sql, name)
+        "(#{select_sql}) AS #{quote_table_name(name)}"
+      end
+      
+      def table(table)
+        quote_table_name(table.name) + (table.name != name_for(table) ? " AS " + engine.quote_table_name(name_for(table)) : '')
+      end
+    end
+    
+    class Attribute < WhereCondition
+      def scalar(scalar)
+        quote(scalar, environment.column)
+      end
+      
+      def array(array)
+        "(" + array.collect { |e| e.to_sql(self) }.join(', ') + ")"
+      end
+      
+      def range(left, right)
+        "#{left} AND #{right}"
+      end
+    end
+    
+    class Value < WhereCondition
+    end
+  end
+end
\ No newline at end of file