from flask_login import current_user
from wtforms.validators import ValidationError
from PIL import Image
from app.models.users import Member, User
from app.models.trophies import Title
from app.utils.valid_name import valid_name
from app.utils.unicode_names import normalize
from math import log
from werkzeug.exceptions import NotFound
import app.utils.ldap as ldap

from config import V5Config

from app.utils.validators.file import *

# TODO: clean this shit into split files

def name_valid(form, name):
    valid = valid_name(name.data)
    default = "Nom d'utilisateur invalide (erreur interne)"
    msg = {
        "too-short":
            "Le nom d'utilisateur doit faire au moins "
            f"{User.NAME_MINLEN} caractères.",
        "too-long":
            "Le nom d'utilisateur doit faire au plus "
            f"{User.NAME_MAXLEN} caractères.",
        "cant-normalize":
            "Ce nom d'utilisateur contient des caractères interdits. Les "
            "caractères autorisés sont les lettres, lettres accentuées, "
            'chiffres ainsi que "-" (tiret), "." (point), "~" (tilde) et '
            '"_" (underscore).',
        "no-letter":
            "Le nom d'utilisateur doit contenir au moins une lettre.",
        "forbidden":
            "Ce nom d'utilisateur est interdit."
    }
    if valid is not True:
        err = ' '.join(msg.get(code, default) for code in valid)
        raise ValidationError(err)

def name_available(form, name):
    # If the name is invalid, name_valid() will return a meaningful message
    try:
        norm = normalize(name.data)
    except ValueError:
        return

    member = Member.query.filter_by(norm=norm).first()
    if member is not None:
        raise ValidationError("Ce nom d'utilisateur est indisponible.")

    # Double check with LDAP if needed
    if V5Config.USE_LDAP:
        member = ldap.get_member(norm)
        if member is not None:
            raise ValidationError("Ce nom d'utilisateur est indisponible.")

def email(form, email):
    member = Member.query.filter_by(email=email.data).first()
    if member is not None:
        raise ValidationError('Adresse email déjà utilisée.')

def password(form, password):
    # To avoid errors in forms where password is optionnal
    if len(password.data) == 0:
        return

    def entropy(password):
        """Estimate entropy of a password, in bits"""
        # If you edit this function, please edit accordingly the JS one
        # in static/script/entropy.js
        chars = [
            "abcdefghijklmnopqrstuvwxyz",
            "ABCDFEGHIJKLMNOPQRSTUVWXYZ",
            "0123456789",
            " !\"#$%&'()*+,-./:;<=>?@[\\]^_`{|}~§",  # OWASP special chars
            "áàâéèêíìîóòôúùûç",
        ]
        used = set()
        for c in password:
            for i in chars:
                if c in i:
                    used.add(i)
        return log(len(''.join(used)) ** len(password), 2)

    if entropy(password.data) < 60:
        raise ValidationError("Mot de passe pas assez complexe")

def avatar(form, avatar):
    try:
        Image.open(avatar.data)
    except IOError:
        raise ValidationError("Avatar invalide")

def old_password(form, field):
    if field.data:
        if not form.old_password.data:
            raise ValidationError('Votre ancien mot de passe est requis pour cette modification.')
        if not current_user.check_password(form.old_password.data):
            raise ValidationError('Mot de passe actuel erroné.')

def id_exists(object):
    """Check if an id exists in a table"""
    def _id_exists(form, id):
        try:
            id = int(id.data)
        except ValueError:
            raise ValidationError('L\'id n\'est pas un entier valide')
        r = object.query.filter_by(id=id)
        if not r:
            raise ValidationError('L\'id n\'existe pas dans la BDD')
    return _id_exists

def css(form, css):
    """Check if input is valid and sane CSS"""
    pass

def own_title(form, title):
    # Everyone can use "Member"
    if title.data == -1:
        return True

    try:
        t = Title.query.get_or_404(title.data)
    except NotFound:
        return False
    except ValueError:
        return False

    if t in current_user.trophies:
        return True
    else:
        return False