# coding=utf-8

from python.util import has_token_sequence
from server.hints import Hint, HintSequence

id = 180
group = 'introduction'
number = 1
visible = True

solution = '''\
f = float(input("Temperatura [F]: "))
 c = 5/9 * (f – 32)
print("Temperatura je", c, "C")
'''

hint_type = {
    'plan': Hint('plan'),
    'no_input_call': Hint('no_input_call'),
    'expressions_python': Hint('expressions_python'),
    'printing': Hint('printing'),
    'name_error': HintSequence('name_error', 4),
    'unsupported_operand': HintSequence('unsupported_operand', 4),
    'not_callable': HintSequence('not_callable', 4),
}

def test(python, code):
    # List of inputs: (expression to eval, stdin).
    test_in = [
        (None, '32\n'),
        (None, '212\n'),
        (None, '-459.4\n'),
        (None, '98.6\n'),
        (None, '1832\n'),
    ]
    test_out = [
        '0',
        '100',
        '-273',
        '37',
        '1000'
    ]

    # List of outputs: (expression result, stdout, stderr, exception).
    answers = python(code=code, inputs=test_in, timeout=1.0)
    outputs = [ans[1] for ans in answers]

    n_correct = 0
    for output, correct in zip(outputs, test_out):
        if correct in output:
            n_correct += 1
    return n_correct, len(test_in)

def hint(python, code):
    # run one test first to see if there are any exceptions
    test_in = [(None, '212\n')]
    exc = python(code=code, inputs=test_in, timeout=1.0)[0][3]
    # have an exception!
    if exc:
        if 'NameError' in exc:
            return [{'id':'name_error', 'args': {'message': exc}}]
        elif 'not callable' in exc:
            return [{'id':'not_callable', 'args': {'message': exc}}]
        elif 'unsupported operand' in exc:
            return [{'id':'unsupported_operand', 'args': {'message': exc}}]
        elif 'TypeError' in exc:
            return [{'id':'unsupported_operand', 'args': {'message': exc}}]


    # the trick is to decide when to show the plan and when the first hint. 
    # I implemented a simple idea: show plan, when code contains something from the 
    # solution, but not input. 
    if len(code.strip()) < 5 or (not has_token_sequence(code, ['input']) and
                    (has_token_sequence(code, ['32']) or 
                     has_token_sequence(code, ['=', '5']) or 
                     has_token_sequence(code, ['print']))):
        return [{'id': 'plan'}]


    # if input is not present in code, student needs to learn about input
    if not has_token_sequence(code, ['input']):
        return [{'id': 'no_input_call'}]

    # if tokens * or / or = are not in code, we have to teach them how to 
    # evaluate expressions.
    if (not has_token_sequence(code, ['/']) or
        not has_token_sequence(code, ['*']) or
        not has_token_sequence(code, ['='])):
        return [{'id' : 'expressions_python'}]

    # student is not using print function
    if not has_token_sequence(code, ['print']):
        return [{'id' : 'printing'}]

    return None