"""Web Push HTTP endpoints.

GET  /push/vapid-public-key       — publiczny klucz VAPID dla klienta JS
POST /push/subscribe              — zapisz subskrypcję w DB
POST /push/unsubscribe            — usuń subskrypcję
POST /push/test                   — self-push (test własnego subskrybenta)
POST /push/pending-url            — (iOS PWA) zapis URL z notificationclick
GET  /push/pending-url            — odczytaj i wyczyść pending URL
"""

import logging
from datetime import datetime

from flask import jsonify, request
from flask_login import login_required, current_user

from database import SessionLocal, PushSubscription
from extensions import limiter
from . import bp
from .push_service import (
    send_push,
    set_pending_url,
    pop_pending_url,
    _vapid_public_key,
)

logger = logging.getLogger(__name__)


def exempt_from_csrf(app):
    """Exempt push routes from CSRF protection (JS fetch from SW + frontend)."""
    csrf = app.extensions.get('csrf')
    if csrf:
        csrf.exempt(bp)


@bp.route('/vapid-public-key', methods=['GET'])
@login_required
@limiter.exempt
def vapid_public_key():
    key = _vapid_public_key()
    if not key:
        return jsonify({'error': 'VAPID not configured'}), 503
    return jsonify({'key': key})


@bp.route('/subscribe', methods=['POST'])
@login_required
@limiter.limit('30 per minute')
def subscribe():
    payload = request.get_json(silent=True) or {}
    endpoint = (payload.get('endpoint') or '').strip()
    keys = payload.get('keys') or {}
    p256dh = (keys.get('p256dh') or '').strip()
    auth = (keys.get('auth') or '').strip()
    if not endpoint or not p256dh or not auth:
        return jsonify({'error': 'endpoint, p256dh i auth wymagane'}), 400

    user_agent = (request.headers.get('User-Agent') or '')[:500]
    db = SessionLocal()
    try:
        existing = db.query(PushSubscription).filter_by(endpoint=endpoint).first()
        if existing:
            existing.user_id = current_user.id
            existing.p256dh = p256dh
            existing.auth = auth
            existing.user_agent = user_agent
            existing.last_used_at = datetime.now()
        else:
            sub = PushSubscription(
                user_id=current_user.id,
                endpoint=endpoint,
                p256dh=p256dh,
                auth=auth,
                user_agent=user_agent,
            )
            db.add(sub)
        db.commit()
        return jsonify({'ok': True})
    except Exception as e:
        db.rollback()
        logger.error("push subscribe error: %s", e)
        return jsonify({'error': 'Błąd zapisu subskrypcji'}), 500
    finally:
        db.close()


@bp.route('/unsubscribe', methods=['POST'])
@login_required
@limiter.limit('30 per minute')
def unsubscribe():
    payload = request.get_json(silent=True) or {}
    endpoint = (payload.get('endpoint') or '').strip()
    if not endpoint:
        return jsonify({'error': 'endpoint wymagany'}), 400

    db = SessionLocal()
    try:
        sub = db.query(PushSubscription).filter_by(
            endpoint=endpoint, user_id=current_user.id
        ).first()
        if sub:
            db.delete(sub)
            db.commit()
        return jsonify({'ok': True})
    except Exception as e:
        db.rollback()
        logger.error("push unsubscribe error: %s", e)
        return jsonify({'error': 'Błąd'}), 500
    finally:
        db.close()


@bp.route('/test', methods=['POST'])
@login_required
@limiter.limit('5 per minute')
def test_push():
    stats = send_push(
        user_id=current_user.id,
        title='🔔 Powiadomienia działają',
        body='To testowe powiadomienie. Zobaczysz takie okienko kiedy ktoś napisze do Ciebie wiadomość.',
        url='/wiadomosci',
        tag='push-test',
    )
    return jsonify({'ok': True, **stats})


@bp.route('/pending-url', methods=['POST'])
@login_required
@limiter.limit('60 per minute')
def pending_url_set():
    payload = request.get_json(silent=True) or {}
    url = (payload.get('url') or '').strip()
    if not url or not url.startswith('/'):
        return jsonify({'error': 'URL must be same-origin path'}), 400
    set_pending_url(current_user.id, url)
    return jsonify({'ok': True})


@bp.route('/pending-url', methods=['GET'])
@login_required
@limiter.exempt
def pending_url_get():
    url = pop_pending_url(current_user.id)
    return jsonify({'url': url})


@bp.route('/pending-url/clear', methods=['POST'])
@login_required
@limiter.exempt
def pending_url_clear():
    pop_pending_url(current_user.id)
    return jsonify({'ok': True})