from flask import Blueprint, render_template, request, redirect, url_for, current_app
from .extensions import db
from .models import Adresse, Frage, Antwort
from utils import generate_vcard
import re

# Prefer robust validators when available; fall back to simple checks.
try:
    from email_validator import validate_email, EmailNotValidError
except Exception:
    validate_email = None
    EmailNotValidError = Exception

try:
    import phonenumbers
except Exception:
    phonenumbers = None


bp = Blueprint('public', __name__)


@bp.route('/', methods=['GET', 'POST'])
def index():
    if request.method == 'POST':
        vorname = request.form.get('vorname', '').strip()
        nachname = request.form.get('nachname', '').strip()
        strasse = request.form.get('strasse', '').strip()
        hausnummer = request.form.get('hausnummer', '').strip()
        plz = request.form.get('plz', '').strip()
        ort = request.form.get('ort', '').strip()
        land = request.form.get('land', 'Deutschland').strip()
        telefon_vorwahl = request.form.get('telefon_vorwahl', '').strip()
        telefon_nummer = request.form.get('telefon_nummer', '').strip()
        email = request.form.get('email', '').strip()

        errors = {}

        # Email validation: use `email_validator` if present, else fallback regex
        if email:
            if validate_email:
                try:
                    # disable deliverability checks (MX/DNS) to avoid rejecting
                    # addresses like max@example.com during testing
                    valid = validate_email(email, check_deliverability=False)
                    email = valid.email
                except EmailNotValidError:
                    errors['email'] = 'Ungültige E-Mail-Adresse'
            else:
                email_re = re.compile(r"[^@]+@[^@]+\.[^@]+")
                if not email_re.match(email):
                    errors['email'] = 'Ungültige E-Mail-Adresse'

        # German PLZ: exactly 5 digits
        if plz:
            if not plz.isdigit() or len(plz) != 5:
                errors['plz'] = 'Postleitzahl muss genau 5 Ziffern haben'

        # Phone validation: require both country code and number when provided
        if telefon_vorwahl or telefon_nummer:
            if not (telefon_vorwahl and telefon_nummer):
                errors['telefon'] = 'Vorwahl und Telefonnummer müssen beide angegeben werden'
            else:
                if phonenumbers:
                    raw = telefon_vorwahl.lstrip('+') + telefon_nummer
                    international = '+' + raw
                    try:
                        parsed = phonenumbers.parse(international, None)
                        is_valid = phonenumbers.is_valid_number(parsed)
                    except Exception:
                        is_valid = False
                    # if phonenumbers says invalid, fall back to a simple heuristic
                    if not is_valid:
                        if not (telefon_vorwahl.lstrip('+').isdigit() and telefon_nummer.isdigit()) or len(telefon_nummer) < 3:
                            errors['telefon'] = 'Ungültige Telefonnummer'
                else:
                    # fallback: basic numeric checks
                    if not (telefon_vorwahl.lstrip('+').isdigit() and telefon_nummer.isdigit()):
                        errors['telefon'] = 'Ungültige Telefonnummer'
                    elif len(telefon_nummer) < 3:
                        errors['telefon'] = 'Ungültige Telefonnummer'

        if errors:
            fragen = Frage.query.all()
            form = request.form.to_dict()
            return render_template('index.html', fragen=fragen, errors=errors, form=form)

        adresse = Adresse(
            vorname=vorname,
            nachname=nachname,
            strasse=strasse,
            hausnummer=hausnummer,
            plz=plz,
            ort=ort,
            land=land,
            telefon_vorwahl=telefon_vorwahl,
            telefon_nummer=telefon_nummer,
            email=email,
        )
        db.session.add(adresse)
        db.session.commit()

        fragen = Frage.query.all()
        for frage in fragen:
            key = f'frage_{frage.id}'
            antwort_text = request.form.get(key, '').strip()
            antwort = Antwort(adresse_id=adresse.id, frage_id=frage.id, text=antwort_text)
            db.session.add(antwort)
        db.session.commit()

        try:
            base_dir = current_app.config.get('BASE_DIR') if current_app.config.get('BASE_DIR') else getattr(current_app, 'BASE_DIR', '.')
            generate_vcard(adresse, base_dir)
        except Exception:
            current_app.logger.exception('Fehler beim Erzeugen der vCard for adresse id=%s', adresse.id if hasattr(adresse, 'id') else 'unknown')

        return redirect(url_for('public.danke', id=adresse.id))

    fragen = Frage.query.all()
    return render_template('index.html', fragen=fragen)


@bp.route('/danke')
def danke():
    ad_id = request.args.get('id')
    adresse = db.session.get(Adresse, int(ad_id)) if ad_id else None
    return render_template('danke.html', adresse=adresse)