:- module('gst',[]).

en("the target language is: prolog. 
    
the templates are:
*an entity* does not operate for profit.
*an entity* must register for GST. 
*an entity* has *a turnover*. 
*an entity* projected turnover is *a turnover*. 
*an entity* has *a turnover*. 
the turnover of *an entity* for the current month is *an amount*.    
the turnover of *an entity* for the previous 11 months is *an amount*. 
the turnover of *an entity* for the next 11 months is *an amount*.
    
the ontology is:
    
sporting club is an entity.
charity is an entity.
community group is an entity.
professional association is an entity.    

an entity is a not-for-profit if the entity does not operate for profit. 
        
the knowledge base gst includes:

an entity must register for GST 
    if the entity is a not-for-profit
    and		the entity has a turnover 
    		and the turnover >= 150000
    	or	the entity projected turnover is a projection 
    		and the projection >= 150000. 

an entity must register for GST 
    if it is not the case that
    	the entity is a not-for-profit
    and 	the entity has a turnover 
   			and the turnover >= 75000 
    	or the entity projected turnover is a projection
    		and the projection >= 75000.

an entity has a current turnover
    if the turnover of the entity for the current month is a monthly amount
    and the turnover of the entity for the previous 11 months is a past amount
    and the current turnover = monthly amount + past amount. 

an entity projected turnover is a projection
    if the turnover of the entity for the current month is a monthly amount
    and the turnover of the entity for the next 11 months is a future amount
    and the projection = monthly amount + future amount. 
    
scenario A is:
Cherrio Charity is an entity. 
Cherrio Charity does not operate for profit. 
Cherrio Charity has 160000. 
    
query A is:
Cherrio Charity must register for GST. 
% yes
    
scenario B is: 
sporting club does not operate for profit.
sporting club projected turnover is 100000. 
        
query B is:
sporting club must register for GST. 
% no
    
scenario C is: 
Tom s Bakery is an entity.
Tom s Bakery has 80000.
    
query C is: 
Tom s Bakery must register for GST.
% yes
    
query not-for-profit is:
which entity is a not-for-profit. 
    
").

/** <examples>
?- answer("query A with scenario A").
?- answer("query B with scenario B").
?- answer("query C with scenario C").
?- answer('C', with('C'), le(R), L). 
?- answer('B', with('B'), le(R), L). 
?- answer('A', with('A'), le(R), L). 
?- answer('not-for-profit', with('B'), le(R), L).
*/