freeagent.rb

require 'rubygems'
require 'restclient'
require 'crack'
require 'mash'
require 'active_support'

RestClient::Resource.class_eval do
  def root
    self.class.new(URI.parse(url).merge('/').to_s, options)
  end
end

module FreeAgent
  class Company
    def initialize(domain, username, password)
      @resource = RestClient::Resource.new(
        "https://#{domain}.freeagentcentral.com",
        :user => username, :password => password
      )
    end
    
    def invoices
      @invoices ||= Collection.new(@resource['/invoices'], :entity => :invoice)
    end
    
    def contacts
      @contacts ||= Collection.new(@resource['/contacts'], :entity => :contact)
    end
    
    def expenses(user_id, options={})
      options.assert_valid_keys(:view, :from, :to)
      options.reverse_merge!(:view => 'recent')
      
      if options[:from] && options[:to]
        options[:view] = "#{options[:from].strftime('%Y-%m-%d')}_#{options[:to].strftime('%Y-%m-%d')}"
      end
      
      Collection.new(@resource["/users/#{user_id}/expenses?view=#{options[:view]}"], :entity => :expense)
    end
  end
  
  class Collection
    def initialize(resource, options={})
      @resource = resource
      @entity = options.delete(:entity)
    end
    
    def url
      @resource.url
    end
    
    def find(id)
      entity_for_id(id).reload
    end
    
    def find_all
      case (response = @resource.get).code
      when 200
        if entities = Crack::XML.parse(response)[@entity.to_s.pluralize]
          entities.map do |attributes|
            entity_for_id(attributes['id'], attributes)
          end
        else
          []
        end
      end
    end
    
    def create(attributes)
      payload = attributes.to_xml(:root => @entity.to_s )
      case (response = @resource.post(payload, 
        :content_type => 'application/xml', :accept => 'application/xml')).code
      when 201
        resource_path = URI.parse(response.headers[:location]).path
        Entity.new(@resource.root[resource_path], @entity)
      end
    end
    
    def update(id, attributes)
      entity_for_id(id).update(attributes, headers)
    end
    
    def destroy(id)
      entity_for_id(id).destroy
    end
    
    private
    
    def entity_for_id(id, attributes={})
      Entity.new(@resource["/#{id}"], @entity, attributes)
    end
  end
  
  class Entity
    attr_reader :attributes
    
    def initialize(resource, entity, attributes = {})
      @resource, @entity = resource, entity
      @attributes = attributes.to_mash
    end
    
    def url
      @resource.url
    end
    
    def collection(path, entity)
      Collection.new(@resource[path], :entity => entity)
    end
    
    def reload
      returning(self) do
        @attributes = Crack::XML.parse(@resource.get)[@entity.to_s].to_mash
      end
    end
    
    def update(attributes = {})
      @resource.put(attributes.to_xml(:root => @entity.to_s.downcase),
        :content_type =>'application/xml', :accept => 'application/xml')
    end
    
    def destroy
      @resource.delete
    end
    
    private
    
    def method_missing(*args)
      @attributes.send(*args)
    end
  end
end