// simple services ontology

serviceProfile[name => string,
		  hasCategory => category,
        hasPrecondition => condition,
        hasPostcondition => condition].
        
goal[hasProfile => serviceProfile].

service[hasProfile => serviceProfile].

// description of conditions is very simple: just a name
condition[name => string].

category[name => string].

//service categories
sellingService:category.
bookSellingService::sellingService.
amazonBookSellingService::bookSellingService.
computerSellingService::sellingService.

//preconditions

// address for delivery is supplied
deliveryInfo:condition.
//bank account information is supplied
bankInfo:condition.
//credit card information is supplied
ccInfo:condition.

bankAndDeliveryInfo::deliveryInfo.
bankAndDeliveryInfo::bankInfo.

ccAndDeliveryInfo::deliveryInfo.
ccAndDeliveryInfo::ccInfo.


//effects

//article is delivered
delivered:condition.
//bank account has been charged
bankCharged:condition.
//credit card has been charged
ccCharged:condition.

bankChargedAndDelivered::delivered.
bankChargedAndDelivered::bankCharged.

ccChargedAndDelivered::delivered.
ccChargedAndDelivered::ccCharged.



//two example service profiles
myBookSeller:serviceProfile[name -> "book seller",
		  hasCategory -> amazonBookSellingService,
        hasPrecondition -> ccAndDeliveryInfo,
        hasEffect -> ccChargedAndDelivered].

myBookSeller2:serviceProfile[name -> "book seller",
		  hasCategory -> bookSellingService,
        hasPrecondition -> bankAndDeliveryInfo,
        hasEffect -> bankChargedAndDelivered].

//example service and example goal
myService:service[hasProfile -> myBookSeller].
myGoal:goal[hasProfile -> myBookSeller2].


// simple matching mechanism based on categories. There is a match if the category of
//  the service is a subclass of or the same as the category of the goal
match(?x,?y) :- ?x:goal[hasProfile -> ?p1[hasCategory -> ?c1]], 
   ?y:service[hasProfile -> ?p2[hasCategory -> ?c2]], ?c2::?c1.
match(?x,?y) :- ?x:goal[hasProfile -> ?p1[hasCategory -> ?c1]], 
   ?y:service[hasProfile -> ?p2[hasCategory -> ?c2]], ?c2=?c1.
   
// query all matching goals/services with:
//   ?- match(?x,?y).
// query all services matching my goal:
//   ?- match(myGoal,?y).
// query whether a particular service matches my goal
//   ?- match(myGoal,myService).