20100216233059_create_shirts.rb

class CreateShirts < ActiveRecord::Migration
  def self.up
    create_table :shirts do |t|
      t.string :size
      t.string :color
      t.string :style
      t.belongs_to :design
      t.belongs_to :order
      t.timestamps
    end
  end

  def self.down
    drop_table :shirts
  end
end

20100216233104_create_orders.rb

class CreateOrders < ActiveRecord::Migration
  def self.up
    create_table :orders do |t|
      t.datetime :paid
      t.datetime :shipped
      t.belongs_to :customer
      t.timestamps
    end
  end

  def self.down
    drop_table :orders
  end
end

20100216233114_create_customers.rb

class CreateCustomers < ActiveRecord::Migration
  def self.up
    create_table :customers do |t|
      t.string  :first_name
      t.string  :last_name
      t.boolean :artist
      t.timestamps
    end
  end

  def self.down
    drop_table :customers
  end
end

20100216233123_create_designs.rb

class CreateDesigns < ActiveRecord::Migration
  def self.up
    create_table :designs do |t|
      t.string :image
      t.belongs_to :customer
      t.timestamps
    end
  end

  def self.down
    drop_table :designs
  end
end

customer.rb

class Customer < ActiveRecord::Base
  Customer.has_many(:designs) # as a designer
  Customer.has_many(:orders)
end

design.rb

class Design < ActiveRecord::Base
  Design.has_many(:shirts)
  Design.belongs_to(:customer) # the person who designed it
  Design.has_many(:orders, {:through => :shirts})
end

designs_controller.rb

class DesignsController < ApplicationController
  def index
    
  end
  
  def show
    
  end
end

items_controller.rb

class ItemsController < ApplicationController
  def new
    
  end
  
  def create
    
  end
end

order.rb

class Order < ActiveRecord::Base
  Order.belongs_to(:customer)
  Order.has_many(:items)
end

orders_controller.rb

class OrdersController < ApplicationController
  def new
    
  end
  
  def new
    
  end
  
  def create
    
  end
end

routes.rb

ActionController::Routing::Routes.draw do |map|
  map.site_root('/', {
    :controller => 'designs',
    :action     => 'index',
    :conditions => {:method => :get}
  })
  map.design('/designs/:permalink', {
    :controller => 'designs',
    :action     => 'show',
    :conditions => {:method => :get}
  })
  map.new_item('/buy/:design_permalink', {
    :controller => 'items',
    :action     => 'new',
    :conditions => {:method => :get}
  })
  map.add_item_to_cart('/items', {
    :controller => 'items',
    :action     => 'create',
    :conditions => {:method => :post}
  })
  map.shopping_cart('/checkout', {
    :controller => 'orders',
    :action     => 'new',
    :conditions => {:method => :get}
  })
  map.finalize_order('/orders', {
    :controller => 'orders',
    :action     => 'create',
    :conditions => {:method => :post}
  })
end

shirt.rb

class Shirt < ActiveRecord::Base
  Shirt.belongs_to(:design)
  Shirt.belongs_to(:order)
end