Split article pages into 2 fields

app/decorators/article_decorator.rb

@@ -6,11 +6,19 @@ def author_names
     authors.map { |author| "<span class=nowrap>#{author.full_name}</span>" }.join(', ').html_safe
   end
 
+  def pages
+    source.first_page.to_s + source.other_pages.to_s
+  end
+
   def keyword_list
     keywords.pluck(:name).join(', ')
   end
 
   def pdf_download_link
     h.link_to('Download', pdf.url) if pdf_file_name
   end
+
+  def page_title
+    [volume.roman_numeral, pages].reject(&:blank?).join(': ')
+  end
 end

app/models/article.rb

@@ -10,6 +10,16 @@ class Article < ActiveRecord::Base
 
   validates :title, presence: true
   validates :volume, presence: true
+  validate :pages_format
+
+  def pages=(pages_str)
+    @pages = pages_str
+    self.first_page, self.other_pages = split_pages(pages_str) unless pages_str.blank?
+  end
+
+  def pages
+    [first_page.to_s, other_pages.to_s].join
+  end
 
   def keyword_names=(val)
     names = val.split(/,\s*/)
@@ -19,4 +29,17 @@ def keyword_names=(val)
   def keyword_names
     keywords.pluck(:name).join(',')
   end
+
+  private
+
+  def pages_format
+    unless pages.blank? || @pages =~ /\A\d+\s*([-,]\s*\d+\s*)*\z/
+      errors.add(:pages, 'must be a series of page numbers separated by "," or "-"')
+    end
+  end
+
+  def split_pages(pages_str)
+    parts = pages_str.gsub(' ', '').split(/(-|,)/)
+    [parts[0], parts[1..-1].join]
+  end
 end

db/migrate/20130902014903_create_articles.rb

@@ -3,7 +3,8 @@ def change
     create_table :articles do |t|
       t.belongs_to :volume, index: true
       t.string     :title
-      t.string     :pages
+      t.integer    :first_page
+      t.string     :other_pages
       t.attachment :pdf
 
       t.timestamps

spec/decorators/article_decorator_spec.rb

@@ -0,0 +1,23 @@
+require 'spec_helper'
+
+describe ArticleDecorator do
+  describe '#pages' do
+    it 'combines the first_page and other_pages fields' do
+      article = FactoryGirl.build_stubbed(:article, first_page: '1', other_pages: '-20')
+
+      expect(article.decorate.pages).to eql('1-20')
+    end
+
+    it 'handles articles that only have a first_page' do
+      article = FactoryGirl.build_stubbed(:article, first_page: '1', other_pages: nil)
+
+      expect(article.decorate.pages).to eql('1')
+    end
+
+    it "handles articles that don't have any pages" do
+      article = FactoryGirl.build_stubbed(:article, first_page: nil, other_pages: nil)
+
+      expect(article.decorate.pages).to eql('')
+    end
+  end
+end

spec/models/article_spec.rb

@@ -9,4 +9,46 @@
 
   it { should validate_presence_of(:title) }
   it { should validate_presence_of(:volume) }
+  it { should allow_value('').for(:pages) }
+  it { should allow_value('1').for(:pages) }
+  it { should allow_value('1-10').for(:pages) }
+  it { should allow_value('1 - 10').for(:pages) }
+  it { should allow_value('1,10').for(:pages) }
+  it { should allow_value('1, 10').for(:pages) }
+  it { should allow_value('1,10-20').for(:pages) }
+  it { should allow_value('1-10,20').for(:pages) }
+  it { should_not allow_value('123x').for(:pages) }
+  it { should_not allow_value('1-').for(:pages) }
+
+  describe '#split_pages' do
+    it 'splits two numbers separated by a hyphen' do
+      pages_input = '1-10'
+      article = FactoryGirl.build(:article, pages: pages_input)
+
+      article.save
+
+      expect(article.first_page).to eql(1)
+      expect(article.other_pages).to eql('-10')
+    end
+
+    it 'strips out spaces surrounding the hyphen' do
+      pages_input = '1 - 10'
+      article = FactoryGirl.build(:article, pages: pages_input)
+
+      article.save
+
+      expect(article.first_page).to eql(1)
+      expect(article.other_pages).to eql('-10')
+    end
+
+    it 'splits two numbers separated by a comma' do
+      pages_input = '1,10'
+      article = FactoryGirl.build(:article, pages: pages_input)
+
+      article.save
+
+      expect(article.first_page).to eql(1)
+      expect(article.other_pages).to eql(',10')
+    end
+  end
 end