from zxcvbn.scoring import START_UPPER, ALL_UPPER
from gettext import gettext as _


def get_feedback(score, sequence):
    if len(sequence) == 0:
        return {
            'warning': '',
            'suggestions': [
                _("Use a few words, avoid common phrases."),
                _("No need for symbols, digits, or uppercase letters.")
            ]
        }

    if score > 2:
        return {
            'warning': '',
            'suggestions': [],
        }

    longest_match = sequence[0]
    for match in sequence[1:]:
        if len(match['token']) > len(longest_match['token']):
            longest_match = match

    feedback = get_match_feedback(longest_match, len(sequence) == 1)
    extra_feedback = _('Add another word or two. Uncommon words are better.')
    if feedback:
        feedback['suggestions'].insert(0, extra_feedback)
        if not feedback['warning']:
            feedback['warning'] = ''
    else:
        feedback = {
            'warning': '',
            'suggestions': [extra_feedback]
        }

    return feedback


def get_match_feedback(match, is_sole_match):
    if match['pattern'] == 'dictionary':
        return get_dictionary_match_feedback(match, is_sole_match)
    elif match['pattern'] == 'spatial':
        if match['turns'] == 1:
            warning = _('Straight rows of keys are easy to guess.')
        else:
            warning = _('Short keyboard patterns are easy to guess.')

        return {
            'warning': warning,
            'suggestions': [
                _('Use a longer keyboard pattern with more turns.')
            ]
        }
    elif match['pattern'] == 'repeat':
        if len(match['base_token']) == 1:
            warning = _('Repeats like "aaa" are easy to guess.')
        else:
            warning = _('Repeats like "abcabcabc" are only slightly harder to ' \
                        'guess than "abc".')
        return {
            'warning': warning,
            'suggestions': [
                _('Avoid repeated words and characters.')
            ]
        }
    elif match['pattern'] == 'sequence':
        return {
            'warning': _('Sequences like "abc" or "6543" are easy to guess.'),
            'suggestions': [
                _('Avoid sequences.')
            ]
        }
    elif match['pattern'] == 'regex':
        if match['regex_name'] == 'recent_year':
            return {
                'warning': _("Recent years are easy to guess."),
                'suggestions': [
                    _('Avoid recent years.'),
                    _('Avoid years that are associated with you.'),
                ]
            }
    elif match['pattern'] == 'date':
        return {
            'warning': _("Dates are often easy to guess."),
            'suggestions': [
                _('Avoid dates and years that are associated with you.'),
            ],
        }


def get_dictionary_match_feedback(match, is_sole_match):
    warning = ''
    if match['dictionary_name'] == 'passwords':
        if is_sole_match and not match.get('l33t', False) and not \
                match['reversed']:
            if match['rank'] <= 10:
                warning = _('This is a top-10 common password.')
            elif match['rank'] <= 100:
                warning = _('This is a top-100 common password.')
            else:
                warning = _('This is a very common password.')
        elif match['guesses_log10'] <= 4:
            warning = _('This is similar to a commonly used password.')
    elif match['dictionary_name'] == 'english':
        if is_sole_match:
            warning = _('A word by itself is easy to guess.')
    elif match['dictionary_name'] in ['surnames', 'male_names',
                                      'female_names', ]:
        if is_sole_match:
            warning = _('Names and surnames by themselves are easy to guess.')
        else:
            warning = _('Common names and surnames are easy to guess.')
    else:
        warning = ''

    suggestions = []
    word = match['token']
    if START_UPPER.search(word):
        suggestions.append(_("Capitalization doesn't help very much."))
    elif ALL_UPPER.search(word) and word.lower() != word:
        suggestions.append(_("All-uppercase is almost as easy to guess as "
                             "all-lowercase."))

    if match['reversed'] and len(match['token']) >= 4:
        suggestions.append(_("Reversed words aren't much harder to guess."))
    if match.get('l33t', False):
        suggestions.append(_("Predictable substitutions like '@' instead of 'a' "
                             "don't help very much."))

    return {
        'warning': warning,
        'suggestions': suggestions,
    }