# coding=utf-8

from operator import itemgetter
import prolog.engine
import server.problems

id = 113
number = 20
visible = True
facts = None

solution = '''\
conc113([], L, L).
conc113([H|T], L2, [H|L]) :-
  conc113(T, L2, L).
shiftleft([H|T], L2) :-
  conc113(T, [H], L2).
'''

test_cases = [
    ('shiftleft([i], X)',
        [{'X': '[i]'}]),
    ('shiftleft([h, e, u, l], X)',
        [{'X': '[e, u, l, h]'}]),
    ('shiftleft([h, A, B, l, c], [x, y, C, D, E])',
        [{'A': 'x', 'B': 'y', 'C': 'l', 'D': 'c', 'E': 'h'}]),
]

def test(code, aux_code):
    n_correct = 0
    engine_id = None
    try:
        engine_id, output = prolog.engine.create(code=code+aux_code, timeout=1.0)
        if engine_id is not None and 'error' not in map(itemgetter(0), output):
            # Engine successfully created, and no syntax error in program.
            for query, answers in test_cases:
                if prolog.engine.check_answers(engine_id, query=query, answers=answers, timeout=1.0):
                    n_correct += 1
    except:
        pass
    finally:
        if engine_id:
            prolog.engine.destroy(engine_id)

    hints = [{'id': 'test_results', 'args': {'passed': n_correct, 'total': len(test_cases)}}]
    return n_correct, len(test_cases), hints

def hint(code, aux_code):
    # TODO
    return []