# coding=utf-8

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

id = 1000
group = 'introduction'
number = 2
visible = True

solution = '''\
from math import *
g = 10
kot = float(input("Vnesi kot (v stopinjah): "))
v = float(input("Vnesi hitrost (v m/s): "))
kot_rad = kot * 2 * pi / 360
razdalja = v ** 2 * sin(2 * kot_rad) / g
print("Kroglo bo odneslo", razdalja, "metrov.")
'''

hint_type = {
    'plan': Hint('plan'),
    'name_error': HintSequence('name_error'),
    'unsupported_operand': HintSequence('unsupported_operand'),
    'syntax_error' : HintSequence('syntax_error'),
    'indentation_error': HintSequence('indentation_error'),
    'no_input_call' : Hint('no_input_call'),
    'radians': HintSequence('radians'),
    'printing': Hint('printing'),
    'math_functions': Hint('math_functions')
}


def almostEqual(a, b, prec=1):
    """ Compares values a and b using at most <code>prec</code> decimal values. """
    return int(a*10**prec) == int(b*10**prec)

def stringAlmostEqual(s, a):
    """ Searches string s for a value that is almost equal to a.

    Args:
        s (str): string to search
        a (float): value to find in string

    Returns:
        bool: True if successful, else False
    """
    for v in s.split():
        try:
            if almostEqual(float(v), a):
                return True
    return False 

def test(python, code):
    # List of inputs: (expression to eval, stdin).
    test_in = [
        (None, '45\n100\n'),
        (None, '44\n100\n'),
        (None, '46\n100\n'),
        (None, '0\n100\n'),
        (None, '90\n100\n'),
        (None, '32\n747\n'),
    ]
    test_out = [
        '1000',
        '999.39',
        '999.39',
        '0.0',
        '0.0',
        '50153.5'
    ]

    # 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 stringAlmostEqual(output, correct):
            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, '45\n')] 
    answer = python(code=code, inputs=test_in, timeout=1.0)
    exc = answer[0][3]
    # if have an exception!
    if exc:
        if 'NameError' in exc:
            return [{'id':'name_error'}]
        if 'unsupported operand' in exc:
            return [{'id':'unsupported_operand'}]
        if 'SyntaxError' in exc:
            return [{'id':'syntax_error'}]
        if 'IndentationError' in exc:
            return [{'id':'indentation_error'}]

    # if result if 893.996, angle is not converted to radians
    if stringAlmostEqual(answer[0][1], 893.996):
        return [{'id': 'radians'}]

    # show plan if student is lost
    if not code or (not has_token_sequence(code, ['input']) and 
                    (has_token_sequence(code, ['pi']) or 
                     has_token_sequence(code, ['sin']) 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']) or \
       not has_token_sequence(code, ['float']):
        return [{'id': 'no_input_call'}]

    # if tokens sqrt or ** are not in code, we have to teach them how to 
    # use math functions.
    if  (not has_token_sequence(code, ['sqrt']) or
        not has_token_sequence(code, ['**']):
        return [{'id' : 'math_functions'}]

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

    return None