# -----------------------------------------------------------------------
#  Copyright © 2012 ShepHertz Technologies Pvt Ltd. All rights reserved.
# -----------------------------------------------------------------------

require "rubygems"
require 'time'
require 'base64'
require 'cgi'
require 'hmac-sha1'
require 'App42Exception.rb'
require 'App42BadParameterException.rb'
require 'App42LimitException.rb'
require 'App42NotFoundException.rb'
require 'App42SecurityException.rb'

module App42
  class Util
    #
    # Finds the current time
    #
    # @return time format
    #
    #
    def get_timestamp_utc
      #time_stamp = Time.now.utc.iso8601
      #time_stamp = Time.now.utc.xmlschema
      time_stamp = Time.now.utc
      time_stamp = time_stamp.strftime("%Y-%m-%dT%H:%M:%S.%LZ")
      puts "TimeStamp - #{time_stamp}"
      time_stamp
    end

    #
    # Finds the particular time for a particular date
    #
    # @param date
    #
    # @return time format
    #
    #

    def get_timestamp_utc_from_date(date)
      time = Time.parse(date).utc
      time_stamp = time.strftime("%Y-%m-%dT%H:%M:%S.%LZ")
      puts "TimeStamp - #{time_stamp}"
      time_stamp
    end

    def get_timestamp_utc_from_date_discount(date)
      time = Time.parse(date).utc
      time_stamp = time.strftime("%a %b %d %l:%M:%S %Z %Y")
      puts "TimeStamp - #{time_stamp}"
      time_stamp
    end

    #
    # This method sorts all the values that are stored in the table.
    #
    # @param table
    # @return sorted string
    #
    #

    def sort_convert_table(table)
      sorted_params = ""
      table.sort {|a,b| a[0] <=> b[0]}.each{ |key, val|
        sorted_params << key
        sorted_params << val
      }
      puts "Sorted params #{sorted_params}"
      sorted_params
    end

    #
    # It signs the request that has to be sent in the Hmac format.
    #
    # @param secretKey
    # @param params
    #
    # @throws InvalidKeyException
    # @throws NoSuchAlgorithmException
    # @throws IllegalStateException
    # @throws UnsupportedEncodingException
    #

    def sign(secret_key, params)
      sorted_params =  sort_convert_table(params)
      puts sorted_params
      signature = compute_hmac(secret_key, sorted_params)
      puts "Signature #{signature}"
      signature
    end

    #
    # Encoding and decoding of the queries are done using the Hmac Algorithm.
    #
    # @param baseString
    # @param key
    #
    # @throws NoSuchAlgorithmException
    # @throws InvalidKeyException
    # @throws IllegalStateException
    # @throws UnsupportedEncodingException
    #

    def compute_hmac(secret_key, sorted_params)
      signature =  Base64.encode64(HMAC::SHA1::digest(secret_key, sorted_params)).strip
      puts "Signature #{signature}"
      computed_hmac = CGI.escape(signature)
      puts "Computed Hmac #{computed_hmac}"
      computed_hmac
    end

    def my_strip(str)
      s =  str.gsub(/ /,'')
      return s
    end

    #
    # An exception to check whether the object is null or blank.
    #
    # @param obj
    # @param name
    #

    def throwExceptionIfNullOrBlank(obj,name)
      if obj.kind_of?(String)
        trm = my_strip(obj)
      else
        trm = obj
      end

      if(trm==nil)
        raise App42Exception.new(name +" parameter can not be null");
      end
      if(trm == "")
        raise App42Exception.new(name +" parameter can not be blank");
      end
    end

    #
    # To check whether the max value is greater than zero or not.
    #
    # @param max
    #

    def validateMax(max)
      if(max.to_i < 1)
        raise App42Exception.new("Max must be greater than Zero.");
      end
    end

    #
    # To check whether the value of how many is less than 1000 or not.
    #
    # @param howMany
    #

    def validateHowMany(howMany)
      if(howMany.to_i > 1000)
        raise App42Exception.new("How Many should be less than 1000");
      end
    end

    #
    # An exception to check whether the email entered is valid or not.
    #
    # @param obj
    # @param name
    #

    def throwExceptionIfEmailNotValid(obj, name)
      if(obj==nil)
        raise App42Exception.new(name +" parameter can not be null")
      end
      email_regex = %r{
               ^ # Start of string

               [0-9a-z] # First character
               [0-9a-z.+]+ # Middle characters
               [0-9a-z] # Last character

               @ # Separating @ character

               [0-9a-z] # Domain name begin
               [0-9a-z.-]+ # Domain name middle
               [0-9a-z] # Domain name end

               $ # End of string
      }xi
      if (obj =~ email_regex) == 0
      else
        raise App42Exception.new(name + " is not valid. ")
      end
    end

    #
    # An exception to check if the file has valid extension or not
    #
    # @param fileName
    # @param name
    #

    def throwExceptionIfNotValidExtension(fileName, name)
      if(fileName==nil)
        raise App42Exception.new(name + " parameter can not be null")
      end
      if(fileName.index('.') == -1)
        raise App42Exception.new(name + " does not contain valid extension. ")
      end
    end

    #
    # Taking extension out
    #
    # @param fileName
    #
    # @return extension
    #

    def extractFileExtension(fileName)
      ext = File.extname(fileName)
      return ext;
    end

    #
    # To check if the image has a valid extension or not.
    #
    # @param fileName
    # @param name
    #

    def throwExceptionIfNotValidImageExtension(fileName, name)

      if(fileName == nil)
        raise App42Exception.new(name + " parameter can not be null")
      end

      if(fileName.index('.') == -1)
        raise App42Exception.new(name + " does not contain valid extension. ")
      end

      ext = extractFileExtension(fileName);
      if((ext.eql?(".jpg") == false) && (ext.eql?(".JPG") == false) && (ext.eql?(".jpeg") == false) && (ext.eql?(".JPEG") == false) && (ext.eql?(".gif") == false) && (ext.eql?(".GIF") == false) && (ext.eql?(".png") == false) && (ext.eql?(".PNG") == false))
        raise App42Exception.new( "The Request parameters are invalid. Only file with extensions jpg, jpeg, gif and png are supported");
      end

    end
  end
end