template_handler.rb in decisive-0.3.0

- old
+ new
@@ -18,46 +18,60 @@
     end
   end
 
   module DSL
     def csv records, filename:, &block
-      Context.new([], records, filename).tap do |context|
-        context.instance_eval &block
-      end
+      Context.new(records, filename, block)
     end
   end
 
-  class Context < Struct.new(:columns, :records, :filename)
-    class Column < Struct.new(:field, :label, :block); end
-
-    def column field, label: field.to_s.humanize, &block
-      block ||= ->(record) { record.send(field) }
-      columns << Column.new(field, label, block)
-    end
-
+  class Context < Struct.new(:records, :filename, :block)
     def to_csv
-      rows
-        .map { |rows| rows.map(&:to_s) }
-        .map(&:to_csv)
-        .join
+      (header + body).map(&:to_csv).join
     end
 
     private
 
-    def rows
-      [header] + body
-    end
-
     def header
-      columns.map(&:label)
+      [keys]
     end
 
     def body
-      records.map do |record|
-        columns.map do |column|
-          column.block.call(record)
-        end
+      hashes.map do |hash|
+        hash.values_at(*keys)
       end
+    end
+
+    def keys
+      @keys ||= hashes.flat_map(&:keys).uniq
+    end
+
+    def hashes
+      @hashes ||= records.map do |record|
+        Row.new(record, block).to_hash
+      end
+    end
+  end
+
+  class Row < Struct.new(:record, :block)
+    def to_hash
+      @hash = {}
+      instance_exec record, &block
+      @hash
+    end
+
+    private
+
+    def column key, value=nil, &block
+      @hash[key] = if block_given?
+        block.call(record)
+      elsif value.is_a?(Symbol)
+        record.send(value)
+      elsif value.nil?
+        record.send(key.parameterize.underscore.to_sym)
+      else
+        value
+      end.to_s
     end
   end
 end
 