Code blog model to use year based directories

app/models/post.rb

@@ -1,17 +1,17 @@
 class Post
   @@posts = nil
 
-  attr_reader :year , :month , :day , :dir , :ext
+  attr_reader :year , :month , :day , :ext
 
   def initialize(path)
-    @dir = File.dirname(path)
-    base , @ext = File.basename(path).split(".")
+    year , rest = *path.split("/")
+    @year = parse_int(year , 2100 , "year")
+    base , @ext = File.basename(rest).split(".")
     raise "must be partial, start with _ not:#{base}" unless base[0] == "_"
     @words = base.split("-")
-    @year = parse_int(@words.shift[1 .. -1] , 2100)
-    @month = parse_int(@words.shift , 12)
-    @day = parse_int(@words.shift , 32)
     raise "Invalid path #{path}" unless @words
+    @month = parse_int(@words.shift[1 .. -1] , 12 , "month")
+    @day = parse_int(@words.shift , 32 , "week")
   end
 
   def slug
@@ -21,18 +21,21 @@ class Post
     @words.join(" ")
   end
   def template_name
-    "#{year}-#{month.to_s.rjust(2, '0')}-#{day.to_s.rjust(2, '0')}-#{@words.join("-")}"
+    "#{year}/#{month.to_s.rjust(2, '0')}-#{day.to_s.rjust(2, '0')}-#{@words.join("-")}"
+  end
+  def template_file
+    "#{year}/_#{month.to_s.rjust(2, '0')}-#{day.to_s.rjust(2, '0')}-#{@words.join("-")}"
   end
   def date
     Date.new(year,month,day)
   end
-  def parse_int( value , max)
+  def parse_int( value , max , name)
     ret = value.to_i
-    raise "invalid value #{value} > #{max}" if ret > max or ret < 1
+    raise "invalid #{name} #{value} > #{max}" if ret > max or ret < 1
     ret
   end
   def content
-    File.open("#{@dir}/_#{template_name}.#{ext}" ).read
+    File.open("#{self.class.blog_path}/#{template_file}.#{ext}" ).read
   end
   def summary
     ret = content.split("%h2").first.gsub("%p", "<br/>").html_safe
@@ -41,15 +44,17 @@ class Post
   def self.posts
     return @@posts if @@posts
     posts ={}
-    Dir["#{self.blog_path}/_2*.haml"].reverse.each do |file|
-      post = Post.new(file)
+    Dir["#{self.blog_path}/2*/_*.haml"].reverse.each do |file|
+      parts = file.split("/")
+      post_name = parts[-2] + "/" + parts[-1]
+      post = Post.new(post_name)
       posts[post.slug] = post
     end
     @@posts = posts.sort_by { |slug, post| post.sort_key }.reverse.to_h
   end
 
   def sort_key
-    year*10000 + month*1000 + day
+    year*1000 + month*10 + day
   end
 
   def self.blog_path