class OEHClient::Interaction::Interaction

	# constants used to construct the restful API Request URL
	API_REALTIME 				= "/interaction"
	API_OFFLINE 				= "/offline"
	# ONE attributes that are either in the request and/or returned in the response
	ONE_PARAM_URI 				= "uri"
	ONE_PARAM_CK				= "customerKey"
	ONE_PARAM_TID 				= "tid"
	ONE_PARAM_SESSION 			= "session"
	ONE_PARAM_SK				= "sk"
	ONE_PARAM_TS				= "timestamp"
	ONE_PARAM_PROPERTIES		= "properties"
	# Property Hash Keys
	ONE_PROPERTIES_NAME			= "name"
	ONE_PROPERTIES_VALUE		= "value"
	# Collection objects returned in the response
	ONE_RESPONSE_OPTIMIZATIONS 	= "optimizations"
	ONE_RESPONSE_TRACKERS		= "trackers"
	ONE_RESPONSE_CAPTURES		= "captures"
	

	attr_accessor 	:uri, 					# The full touchpoint/interaction URI used to post the interaction
					:space, 				# The configured OEHClient::Config::Space object that represents the OEH workspace
	
					:timestamp, 			# A millisecond value representing a Time value of the interaction					
					:customer_key, 			# The customer to which this interaction is related
					:tid, 					# The Thunderhead ID (TID) to which this interaction is related
					:session, 				# The session id to which this interaction is related

					:optimizations,			# The collection of optimizations that are relevent for the interaction 
					:trackers, 				# The collection of tracking point data that are relevant for the interaction
					:captures, 				# The collection of capture point data that are relevant for the interactions

					:errors					

	###
	### -------------  Class Methods
	###
	class << self

		# post
		def post(site_key, uri, timestamp=nil, tid=nil, customer_key=nil, properties={})

			# setup the baseline attributes hash with the site_key and interaction URI, which are the 
			#  minimal values needed for an interaction
			attributes = {
							:sk => site_key,
							:uri => uri
						 }

			# conditionally merge the rest of the attributes if they are passed
			attributes.merge!(:timestamp => timestamp)		unless (timestamp.nil?)
			attributes.merge!(:tid => tid)					if (!tid.nil? && !tid.empty?)
			attributes.merge!(:ck => customer_key)			if (!customer_key.nil? && !customer_key.empty?)


			# create a new interaction using all attributes pass
			new_interaction = OEHClient::Interaction::Interaction.new(attributes)
			# Send the interaction for processing and return the instance of the interaction class
			new_interaction.send(properties)

		end

		# class-level wrapper to create a new instance of the OEHClient::Interaction::Interaction class, call the
		#  send_update method, and return the resulting instance of the same class
		def update(site_key, uri, properties={}, tid=nil, customer_key=nil)

			# setup the baseline attributes hash with the site_key and interaction URI, which are the 
			#  minimal values needed for an interaction
			attributes = {
							:sk => site_key,
							:uri => uri
						 }

			# conditionally merge the rest of the attributes if they are passed
			attributes.merge!(:tid => tid)					if (!tid.nil? && !tid.empty?)
			attributes.merge!(:ck => customer_key)			if (!customer_key.nil? && !customer_key.empty?)

			# create a new interaction using all parameters pass
			new_interaction = OEHClient::Interaction::Interaction.new(attributes)
			# send the update and return the current object
			new_interaction.send_update(properties)

		end

	end

	###
	### -------------  Instance Methods
	###

	def initialize(attributes=nil)

		# set the instance attributes is the parameter hash is created
		if (!attributes.nil? && attributes.kind_of?(Hash))

			@uri 			= attributes[:uri] 			if (attributes.has_key?(:uri))
			@customer_key 	= attributes[:ck] 			if (attributes.has_key?(:ck))
			@tid 			= attributes[:tid] 			if (attributes.has_key?(:tid))
			@session 		= attributes[:session]		if (attributes.has_key?(:session))
			@timestamp 		= attributes[:timestamp] 	if (attributes.has_key?(:timestamp))

			@space 			= OEHClient::Config::SpaceManager.instance.get(attributes[:sk])		if (attributes.has_key?(:sk))

		end

	end

	# send() will post a new interaction using either the realtime (current timestamp) or the offline (historic)
	#  API interface based on the existence of a timestamp value
	def send(parameters={})
		# raise the MissingParameterException when one (or more) of the miminal parameters are missing
		raise OEHClient::Exception::MissingParameterException.new(missing_minimal_parameters) 	unless (minimal_parameters?)

		# call the appropriate method based on the existance of the timestamp value
		((!@timestamp.nil?) ? send_offline(@space.token) : send_realtime(@space.token, parameters))

		# return the current instance interacton
		self
	end

	# send_new posts a new interaction using the existing instance data, but for a different touchpoint 
	#   URI.  The method returns a new instance of the OEHClient::Interaction::Interaction class
	def send_new(uri, timestamp=nil, parameters={})
		# raise the MissingParameterException when one (or more) of the miminal parameters are missing
		raise OEHClient::Exception::MissingParameterException.new(missing_minimal_parameters) 	unless (minimal_parameters?)

		# protect against NIL by creating a new Hash object if the parameters, for any reason is 
		#  NIL
		parameters ||= Hash.new

		# create a new interaction using all parameters from the existing other than the new touchpoint
		#  URI and timestamp of the current Interaction instance.  The method can be used to submit new
		#  requests for the same customer, tid, & session
		new_interaction = OEHClient::Interaction::Interaction.new({
														:uri => uri,
														:ck => @customer_key,
														:tid => @tid,
														:session => @session,
														:sk => @space.site_key,
														:timestamp => timestamp
													})

		# Send the interaction for processing and return the current instance
		new_interaction.send(parameters)
	end

	# send_update allows the system to update the capture and tracking properties that are defined as 
	#  part of the existing interaction
	def send_update(properties={}) 
		# raise the MissingParameterException when one (or more) of the miminal parameters are missing
		raise OEHClient::Exception::MissingParameterException.new(missing_minimal_parameters) 	unless (minimal_parameters?)

		# force the properties object to be an empty Hash if, for any reason, it is NIL
		properties ||= Hash.new

		# Call the PUT method to update the 
		OEHClient::Helper::Response.handle(OEHClient.put(@space.token(), 
														OEHClient::Helper::Request.format_url(realtime_url, {:sk => @space.site_key}),
														nil,
														request_data(properties))) unless properties.empty?
		# return the current object
		self
	end


	private


	# send_realtime posts a new interaction occuring at the moment (in realtime).  The response attributes
	#  are mapped to the current instance attributes for all valid requests
	def send_realtime(token, parameters={})

		response = OEHClient::Helper::Response.handle(OEHClient.post(token, 
																	OEHClient::Helper::Request.format_url(realtime_url, {:sk => @space.site_key}),
																	nil,
																	request_data(parameters))
													)

		map_response(response)


	end

	# send_offline posts a historic interaction, using a specified timestamp
	def send_offline(token)

		response = OEHClient::Helper::Response.handle(OEHClient.put(token,
																	OEHClient::Helper::Request.format_url(offline_url, {:sk => @space.site_key}),
																	nil,
																	request_data))
		map_response(response)


	end

	# map_response takes the attributes returned in an interaction response and maps it to exiting
	#  attributes in the current instance of the interaction object
	def map_response(response)


		# Save the tid and session data if they where not previously used in the request
		@tid 			= response[ONE_PARAM_TID] 		if (@tid.nil? || (!@tid.blank? && @tid != response[ONE_PARAM_TID]))
		@session 		= response[ONE_PARAM_SESSION] 	if @session.nil?

		# capture the optimizations returned from the request and map it to the OEHClient::Interaction::Optimization
		#  class

		# initialize the optimizations collection if it is null
		@optimizations ||= Array.new
		# map each of the optimizations to the OEHClient::Interaction::Optmization class
		response[ONE_RESPONSE_OPTIMIZATIONS].each do | response_optimization |
			@optimizations << OEHClient::Interaction::Optimization.create(response_optimization)
		end

		# capture the trackers returned from the request and mpt it to the OEHClient::Interaction::Tracker 
		# class
		# TODO:  Create OEHClient::Interaction::Tracker class
		@trackers 		= response[ONE_RESPONSE_TRACKERS]

		# capture the capture points returned from the request and map it to the OEHClient::Interaction::Capture 
		# class
		# TODO:  Create OEHClient::Interaction::Capture class
		@captures 		= response[ONE_RESPONSE_CAPTURES]

	end

	# minimal_parameters? determines if the minimal number of request parameters (uri & site_key) are 
	#  present in the current instance of the interaction class. This is a helper method that is used
	#  before making any request
	def minimal_parameters?()
		((!@uri.nil? && !@uri.empty?) && !@space.nil?)
	end

	# missing_minimal_parameters returns an array of the minimal attributes that are missing  from the current
	#  instance of OEHClient::Interaction::Interaction class
	def missing_minimal_parameters

		missing_parameters = []

		missing_parameters << "site_key"	if (!minimal_parameters? && @site_key.nil?)
		missing_parameters << "uri"			if (!minimal_parameters? && @uri.nil?)

		missing_parameters

	end

	# request_url returns the base of the request URL used to make either a realtime or offline request
	#   through published API
	def request_url()
		"#{OEHClient::Helper::Request::ONE_PROTOCOL}#{@space.host}#{OEHClient::Helper::Request::THUNDERHEAD_DOMAIN}#{OEHClient::Helper::Request::ONE_URI_PART}#{OEHClient::Helper::Request::API_URI_PART}#{OEHClient::Helper::Request::API_VERSION}"
	end

	# realtime_url is the interaction part of the API URI 
	def realtime_url()
		"#{request_url}#{API_REALTIME}"
	end

	# offline_url appends the /offiline URI part to add support for historic data loading of interactions
	def offline_url()
		"#{realtime_url}#{API_OFFLINE}"
	end

	# request_data creates a properly formatted Hash object that represents the body of the request needed
	#  for POST and PUT operations
	def request_data(passed_properties={})

		# protect agains a NIL value in the passed_properties Hash
		passed_properties ||= Hash.new

		# Initialize the parameters hash
		parameters ||= Hash.new

		# merge in the different parts of the request data if the values currently exist within
		#  the instance of the class
		parameters.merge!({ONE_PARAM_URI => @uri}) 			if (!@uri.nil? && @uri.length > 0)

		parameters.merge!({ONE_PARAM_CK => @customer_key}) 	if (!@customer_key.nil? && @customer_key.length > 0)
		parameters.merge!({ONE_PARAM_TID => @tid}) 			if (!@tid.nil? && @tid.length > 0)

		parameters.merge!({ONE_PARAM_SESSION => @session}) 	if (!@session.nil? && @session.length > 0)
		parameters.merge!({ONE_PARAM_TS => @timestamp}) 	if (!@timestamp.nil?)

		# for each of the properties hash entry, build a name/value pair in the properties collection
		properties = Array.new
		passed_properties.each do | key, value |
			properties << {ONE_PROPERTIES_NAME => key.to_s, ONE_PROPERTIES_VALUE => value}
		end
		# merge the properties (name / value) connections if there are additonal values to pass
		parameters.merge!({ONE_PARAM_PROPERTIES => properties})		if (properties.length > 0)

		# return the full parameter hash
		return(parameters)

	end




end