<?xml version="1.0"?>

<xs:schema targetNamespace="http://www.ruleml.org/0.91/xsd" xmlns="http://www.ruleml.org/0.91/xsd" xmlns:xs="http://www.w3.org/2001/XMLSchema" elementFormDefault="qualified">

	<xs:annotation>
		<xs:documentation xml:lang="en">
          
            Reaction Rules schema part of Reaction RuleML
            
			This is the XML Schema for reaction rules with event (on).
			
			File: rr.xsd
			Version: 0.2
			Last Modification: 2007-07-01
			
			This schema declares the following Reaction rule elements and attributes:
			
				  * redefines Rule by adding on (event part)
				  * redefines RuleML by Message (messaging reaction rules)
				  * includes algebra module  (complex event and action algebra)
				    and redefined on and do with complex algebra operators and
				    messages
				  
			
			The approach is modelled after that used in "Modularization of XHTML in XML Schema"
			WD [http://www.w3.org/TR/xhtml-m12n-schema/], which will soon be integrated with
			"Modularization of XHTML" (REC-xhtml-modularization-20010410)
			[http://www.w3.org/TR/xhtml-modularization/].
		</xs:documentation>
	</xs:annotation>
	
	<xs:include schemaLocation="http://ibis.in.tum.de/research/ReactionRuleML/0.2/modules/algebra_module.xsd"/>
	<xs:include schemaLocation="http://ibis.in.tum.de/research/ReactionRuleML/0.2/modules/message_module.xsd"/>

	<xs:redefine schemaLocation="http://ibis.in.tum.de/research/ReactionRuleML/0.2/pr.xsd">

		<!--
			rr schema redefines RuleML by adding Message
			note the new content model of RuleML: 
			( oid?,  (Assert | Retract | Query)*, Message? )
						
		-->	

		<xs:group name="RuleML.content">
			<xs:sequence>
				<xs:group ref="RuleML.content"/>				
				<xs:element ref="Message" minOccurs="0"/>
			</xs:sequence>	
		</xs:group>


		<!--
			the RR schema redefines the Rule element
			and adds reaction rules and messaging rules
			to Rule so that Rule's content model is:
			
		    ( oid?, label?, scope?, quantification?,  
	  		(	  	
	  			active reaction rules, e.g. trigger (on-do) or ECA rules (on-if-do)	
	  			(on, if?, then?, do, after?, else?, elseDo?, elseAfter?) |
	  		
	  			special local/inner messaging receive and send reaction rules
	  			(on | do) |
	  		
	  			production rules, such as if-do or special cases such as if-do-elseDo
	  			(if, do, after?, else?, elseDo?, elseAfter?) |
	  		
	  			derivation rules (if-then and if-then-else) and mixed derivation/reaction rules, e.g. if-then-elseDo
	  			(if, then, else?, elseDo?, elseAfter?)
	  		) )	
	  		
	  		The above content model is non-deterministic, the non-deterministic
	  		implementation is:
	  		
	  		( oid?, label?, quantification?,  
	  		 (
	  			(on, (if?, then?, do, after?,else?, elseDo?, elseAfter?)? ) |
	  		 	do |
	  			(if, (do, after?, else?, elseDo?, elseAfter?) | 
	  		     	 (then, else?, elseDo?, else After?) )
	  		 )
	  		)     	 
		-->
			<xs:group name="RuleCore.content">
				<xs:choice>
					<xs:group ref="RuleCore.content"/>			
					<xs:group ref="ReactionRule.content"/>
					<xs:group ref="MessagingRule.content"/>			
				</xs:choice>
			</xs:group>


		<!--
			rr schema redefines on by adding Message
			and event algebra operators so that on's content model is:
			( Naf | Neg | Atom | Rule | Message | Sequence | Disjunction | Xor | Conjunction | Concurrent | Not | Any | Aperiodic | Periodic | Ind | Var | Expr)						
		-->	
		<xs:group name="on.content">
			<xs:choice>
				<xs:group ref="on.content"/>
				<xs:element ref="Message"/>
				<xs:group ref="event_algebra_group.content" />
				<!-- used in complex event definitions -->
				<xs:element ref="Ind"/>
				<xs:element ref="Var"/>
				<xs:element ref="Expr"/>
			</xs:choice>
		</xs:group>

		<!--
			rr schema redefines do, elseDo by adding Message
			and action algebra operators so that on's content model is:
			( Atom | Assert | Retract | Update | Message | Succession | Choice | Flow | Loop | Ind | Var | Expr)						
		-->	
		<xs:group name="do.content">
			<xs:choice>
				<xs:group ref="do.content"/>
				<xs:element ref="Message"/>
				<xs:group ref="action_algebra_group.content" />
				<!-- used in complex event definitions -->
				<xs:element ref="Ind"/>
				<xs:element ref="Var"/>
				<xs:element ref="Expr"/>
			</xs:choice>
		</xs:group>		
	
 	</xs:redefine>

</xs:schema>