require "simplegdata/version"

module SimpleGData
  # A simple class that makes a oauth request using the oauth gem
  # Initialize it by passing in a required oauth token and oauth
  # secret recieved form an external service such as omniauth or
  # the oauth gem.
  class Request
    def initialize(oauth_token, oauth_secret, params = {
                      :application_id     => 'anonymous',
                      :application_secret => 'anonymous',
                      :site               => 'https://www.google.com'
                   })
      # Sets up the class variables.  Defaults to Google's anonymous
      # usage if no account is given.
      @oauth_token        = oauth_token
      @oauth_secret       = oauth_secret
      @application_id     = params[:application_id]
      @application_secret = params[:application_secret]
      @site               = params[:site]
    end
    
    # A class method to make an optimized request to GData's APIS.
    # Automatically converts the request to JSON and accepts a
    # a ruby hash to convert to JSON to send for post data.  Returns
    # results back as a ruby array.
    def request(rest, url, data = nil, options = nil)
      # Default get requests to json 
      if rest == :get && @site == 'https://www.google.com'
        unless url.include? 'alt=json'
          if url.include? '?'
            url = url + '&alt=jsonc'
          else
            url = url + '?alt=jsonc'
          end
        end
      end
      
      # Default post requests to json
      if options.nil?
        options = { 'Content-Type' => 'application/json' }
      else
        unless options.has_key? 'Content-Type'
          options['Content-Type'] = 'application/json'
        end
      end
      
      # Convert any data passed in for post requests to JSON
      if data.class == {}.class
        data = ActiveSupport::JSON.encode(data)
      end
      
      # Run the query and return the results as a ruby object
      response = request_raw(rest, url, data, options)
      ActiveSupport::JSON.decode response
    end
    
    # A class method to process a raw request.  All handling is
    # done by the user.  Deals with the unique issue of GData
    # API's sometimes returning 302 redirects with gsessionids
    # appended to them.
    def request_raw(rest, url, data = nil, options = nil)
      response = access_token.request(rest, url, data, options)
      #end
      case response
        when Net::HTTPSuccess     then response.body
        when Net::HTTPRedirection then access_token.request(rest, response['location'], data, options).body
      else
        response.error!
      end
    end
     
    private
    
    # An internal storage of the access token used to make requests
    def access_token
      @access_token ||= create_access_token
    end
    
    # Creates an oauth token based off the provided credentials
    def create_access_token
      consumer = OAuth::Consumer.new @application_id,
                                     @application_secret,
                                     :site => @site
      token_hash = { :oauth_token        => @oauth_token,
                     :oauth_token_secret => @oauth_secret }
      access_token = OAuth::AccessToken.from_hash(consumer, token_hash)
    end
  end
  
end