from Predicate import *
class AndPredicate(LogicPredicate):
    '''performs an n-way boolean AND on the list of predicates'''
    def holds(self, board, coordinates):
        for predicate in self.predicateList:
            if not predicate.holds(board, coordinates):
                return False
        return True
    
    def __str__(self):
    	return ''.join(["(AND ",' '.join((pl.__str__() for pl in \
    	 self.predicateList)), ")"])

class OrPredicate(LogicPredicate):
    '''performs an n-way boolean OR on the list of predicates'''
    def holds(self, board, coordinates):
        for predicate in self.predicateList:
            if predicate.holds(board, coordinates):
                return True
        return False
        
    def __str__(self):
    	return ''.join(["(OR ",' '.join((pl.__str__() for pl in \
    	 self.predicateList)), ")"])	
        
class NotPredicate(LogicPredicate):
    '''inverts the result of its child predicate'''
    def __init__(self, pred):
        self.Predicate = pred
    def holds(self, board, coordinates):
        return not self.Predicate.holds(board, coordinates)
    def __str__(self):   
        return ''.join(["(NOT ", self.Predicate.__str__(), ")"])