# Copyright (c)  2009 Douglas Willcocks
#
# Permission is hereby granted, free of charge, to any person
# obtaining a copy of this software and associated documentation
# files (the "Software"), to deal in the Software without
# restriction, including without limitation the rights to use,
# copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the
# Software is furnished to do so, subject to the following
# conditions:
# 
# The above copyright notice and this permission notice shall be
# included in all copies or substantial portions of the Software.
# 
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
# OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
# HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
# WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
# FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
# OTHER DEALINGS IN THE SOFTWARE.

# An object describing an abstract API request

module Instapaper
  
  module Request
  
    # The class representing a generic request
    class AbstractRequest

      include Constants
      include Exceptions
      include Protocol

      attr_reader :data
      attr_reader :url

      def initialize #:nodoc:
        @validation_callbacks = Array.new
        @validation_errors    = RequestErrors.new
        @data                 = Hash.new
        @abstract             = true
        @protocol             = PROTOCOLS[:secure]
        @api                  = false
        @validated            = false
      end

      # Prepares the request
      def prepare
        build_url
      end

      # Return a hash of the data to be sent to the server
      #
      # Strict determines whether the method raises an exception
      # or returns an error object
      def post_data(strict = true)
        
        return @data if @validated
        
        raise AbstractRequestException.new if @abstract || !@api
        
        @validation_callbacks.each do |callback|
          unless send(callback.method,*callback.args)
            
            if strict
              raise InvalidRequestDetailsException.new(callback.message)
            else
              @validation_errors << RequestError.new(callback.message,callback.method)
            end
            
          end
        end
        
        if @validation_errors.valid?
          @validated = true
          @data
        else
          @validation_errors
        end
    
      end

      private

      def add_validation_callback(callback) #:nodoc:
        @validation_callbacks << callback unless @validation_callbacks.include?(callback)
      end

      def build_url #:nodoc:
        @url = [@protocol,"://",HOST,"/",API_BASE,"/",@api].join('')
      end

      def has_value(value) #:nodoc:
        !(value.to_s.nil? || value.to_s.empty? || !value)
      end

    end
    
  end
    
end