# Copyright 2011-2012 Amazon.com, Inc. or its affiliates. All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License"). You
# may not use this file except in compliance with the License. A copy of
# the License is located at
#
#     http://aws.amazon.com/apache2.0/
#
# or in the "license" file accompanying this file. This file is
# distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF
# ANY KIND, either express or implied. See the License for the specific
# language governing permissions and limitations under the License.

require 'benchmark'

module AWS
  module Core

    # @private
    module ClientLogging
  
      def log_client_request(name, options)
        response = nil
        time = Benchmark.measure do
          response = yield
        end
  
        if config.logger
          if options[:async]
            response.on_complete do
              log_client_request_on_success(name, options, response, time)
            end
          else
            log_client_request_on_success(name, options, response, time)
          end
        end
        response
      end
  
      # Summarizes long strings and adds file size information
      # @private
      def sanitize_options(options)
        sanitize_hash(options)
      end
  
      protected
      def log severity, message
        config.logger.send(severity, message + "\n") if config.logger
      end
  
      protected
      def log_client_request_on_success(method_name, options, response, time)
        status = response.http_response.status
        service = self.class.service_name
  
        pattern = "[AWS %s %s %.06f %d retries] %s(%s)"
        parts = [
          service, 
          status, 
          time.real, 
          response.retry_count,
          method_name, 
          sanitize_options(options)]

        severity = :info
  
        if response.error
          pattern += " %s: %s"
          parts << response.error.class
          parts << response.error.message
          severity = :error
        end
  
        if response.cached
          pattern << " [CACHED]"
        end
  
        log(severity, pattern % parts)
      end
  
      protected
      def sanitize_value(value)
        case value
        when Hash
          '{' + sanitize_hash(value) + '}'
        when Array
          sanitize_array(value)
        when File
          sanitize_file(value)
        when String
          sanitize_string(value)
        else
          value.inspect
        end
      end
  
      protected
      def sanitize_string str
        inspected = str.inspect
        if inspected.size > config.logger_truncate_strings_at
          summarize_string(str)
        else
          inspected
        end
      end
  
      protected
      def summarize_string str
        # skip the openning "
        string_start = str.inspect[1,config.logger_truncate_strings_at]
        "#<String \"#{string_start}\" ... (#{str.size} characters)>"
      end
  
      protected
      def sanitize_file file
        "#<File:#{file.path} (#{File.size(file.path)} bytes)>"
      end
  
      protected
      def sanitize_array array
        "[" + array.map { |v| sanitize_value(v) }.join(",") + "]"
      end
  
      protected
      def sanitize_hash hash
        hash.map do |k,v|
          "#{sanitize_value(k)}=>#{sanitize_value(v)}"
        end.sort.join(",")
      end
  
    end
  end
end