from datetime import datetime

from flask import session
from flask_wtf import Form
from wtforms import StringField, PasswordField, ValidationError
from wtforms.validators import DataRequired, Email, Length, Regexp
from app.main.dao import verify_codes_dao
from app.main.encryption import check_hash
from app.main.validators import Blacklist


class LoginForm(Form):
    email_address = StringField('Email address', validators=[
        Length(min=5, max=255),
        DataRequired(message='Email cannot be empty'),
        Email(message='Please enter a valid email address')
    ])
    password = PasswordField('Password', validators=[
        DataRequired(message='Please enter your password')
    ])


gov_uk_email = "(^[^@^\\s]+@[^@^\\.^\\s]+(\\.[^@^\\.^\\s]*)*.gov.uk)"
mobile_number = "^\\+44[\\d]{10}$"
verify_code = '^\d{5}$'


class RegisterUserForm(Form):

    def __init__(self, existing_email_addresses, existing_mobile_numbers, *args, **kwargs):
        self.existing_emails = existing_email_addresses
        self.existing_mobiles = existing_mobile_numbers
        super(RegisterUserForm, self).__init__(*args, **kwargs)

    name = StringField('Full name',
                       validators=[DataRequired(message='Name can not be empty')])
    email_address = StringField('Email address', validators=[
        Length(min=5, max=255),
        DataRequired(message='Email cannot be empty'),
        Email(message='Please enter a valid email address'),
        Regexp(regex=gov_uk_email, message='Please enter a gov.uk email address')
    ])
    mobile_number = StringField('Mobile phone number',
                                validators=[DataRequired(message='Please enter your mobile number'),
                                            Regexp(regex=mobile_number, message='Please enter a +44 mobile number')])
    password = PasswordField('Create a password',
                             validators=[DataRequired(message='Please enter your password'),
                                         Length(10, 255, message='Password must be at least 10 characters'),
                                         Blacklist(message='That password is blacklisted, too common')])

    def validate_email_address(self, field):
        # Validate email address is unique.
        if field.data in self.existing_emails:
            raise ValidationError('Email address already exists')

    def validate_mobile_number(self, field):
        # Validate mobile number is unique
        if field.data in self.existing_mobiles:
            raise ValidationError('Mobile number already exists')


class TwoFactorForm(Form):
    sms_code = StringField('sms code', validators=[DataRequired(message='Please enter your code'),
                                                   Regexp(regex=verify_code, message='Code must be 5 digits')])

    def validate_sms_code(self, a):
        return validate_codes(self.sms_code, 'sms')


class VerifyForm(Form):
    sms_code = StringField("Text message confirmation code",
                           validators=[DataRequired(message='SMS code can not be empty'),
                                       Regexp(regex=verify_code, message='Code must be 5 digits')])
    email_code = StringField("Email confirmation code",
                             validators=[DataRequired(message='Email code can not be empty'),
                                         Regexp(regex=verify_code, message='Code must be 5 digits')])

    def validate_email_code(self, a):
        return validate_codes(self.email_code, 'email')

    def validate_sms_code(self, a):
        return validate_codes(self.sms_code, 'sms')


class EmailNotReceivedForm(Form):
    email_address = StringField('Email address', validators=[
        Length(min=5, max=255),
        DataRequired(message='Email cannot be empty'),
        Email(message='Please enter a valid email address'),
        Regexp(regex=gov_uk_email, message='Please enter a gov.uk email address')
    ])


class TextNotReceivedForm(Form):
    mobile_number = StringField('Mobile phone number',
                                validators=[DataRequired(message='Please enter your mobile number'),
                                            Regexp(regex=mobile_number, message='Please enter a +44 mobile number')])


class AddServiceForm(Form):
    def __init__(self, service_names, *args, **kwargs):
        self.service_names = service_names
        super(AddServiceForm, self).__init__(*args, **kwargs)

    service_name = StringField(validators=[DataRequired(message='Please enter your service name')])

    def validate_service_name(self, a):
        if self.service_name.data in self.service_names:
            raise ValidationError('Service name already exists')


def validate_codes(field, code_type):
    codes = verify_codes_dao.get_codes(user_id=session['user_id'], code_type=code_type)
    is_valid = len([code for code in codes if validate_code(field, code)]) == 1
    if is_valid:
        field.errors.clear()
    return is_valid


def validate_code(field, code):
    if field.data and check_hash(field.data, code.code):
        if code.expiry_datetime <= datetime.now():
            field.errors.append('Code has expired')
            return False
        return True
    else:
        field.errors.append('Code does not match')
        return False