import os
import uuid
import smtplib
import pytz
import threading
from email.mime.text import MIMEText
from email.mime.multipart import MIMEMultipart
from itsdangerous import URLSafeTimedSerializer
from werkzeug.security import generate_password_hash, check_password_hash
from flask import Flask, render_template, jsonify, redirect, url_for, request, session, send_from_directory, make_response
from sqlalchemy import or_
from icalendar import Calendar, Event as ICalEvent
from .db import init_db, engine
from . import config, auth, assistant, gitea_api, llm_assistant
from sqlmodel import Session, select
from .models import (
    User, Event, GlobalStatus, Project, PortalFile, UserSession,
    ProjectMember, EventSubscriber, ProjectTask,
    Workshop, WorkshopSession, WorkshopRegistration,
    WorkshopMaterial, WorkshopFeedback, Notification,
)
from datetime import datetime, timezone, timedelta
from functools import wraps

app = Flask(__name__)
app.secret_key = config.WEB_SECRET
serializer = URLSafeTimedSerializer(app.secret_key)

MSK = pytz.timezone("Europe/Moscow")


# ══════════════════════════════════════════════════════════════════════
# БАЗОВЫЕ ХЕЛПЕРЫ И ДЕКОРАТОРЫ (должны быть ДО всех @app.route)
# ══════════════════════════════════════════════════════════════════════

def to_msk(dt):
    if dt is None: return None
    if dt.tzinfo is None: dt = dt.replace(tzinfo=timezone.utc)
    return dt.astimezone(MSK)


@app.template_filter("msk_strftime")
def _msk_strftime(dt, fmt):
    if dt is None: return ""
    return to_msk(dt).strftime(fmt)


@app.template_filter("date_ru")
def _date_ru(d):
    if not d: return ""
    try:
        return datetime.strptime(str(d)[:10], "%Y-%m-%d").strftime("%d.%m.%Y")
    except Exception:
        return str(d)


def require_role(allowed_roles):
    if isinstance(allowed_roles, str):
        allowed_roles = [allowed_roles]
    def decorator(f):
        @wraps(f)
        def decorated_function(*args, **kwargs):
            if session.get("role") not in allowed_roles:
                return "403: Доступ запрещен.", 403
            return f(*args, **kwargs)
        return decorated_function
    return decorator


def login_required(f):
    @wraps(f)
    def decorated_function(*args, **kwargs):
        if not session.get("user_id"):
            return redirect(url_for("login"))
        return f(*args, **kwargs)
    return decorated_function


def parse_datetime(dt_str):
    if not dt_str: return None
    clean_str = dt_str.replace('T', ' ').strip()
    if len(clean_str) > 16: clean_str = clean_str[:16]
    naive = datetime.strptime(clean_str, "%Y-%m-%d %H:%M")
    return MSK.localize(naive).astimezone(timezone.utc)


def normalize_tags(raw):
    if not raw: return None
    parts = {t.strip().lower() for t in raw.split(",") if t.strip()}
    return ",".join(sorted(parts)) if parts else None


def status_label(status_val, delay):
    if status_val == "delayed":
        return f"Опаздываю на {delay} мин"
    return STATUS_LABELS.get(status_val, status_val)


def event_summary_text(ev):
    start = to_msk(ev.start_time).strftime('%d.%m.%Y %H:%M')
    end = to_msk(ev.end_time).strftime('%H:%M')
    lines = [f"Название: {ev.title}", f"Тип: {ev.event_type}", f"Когда: {start} – {end}"]
    if ev.location: lines.append(f"Место: {ev.location}")
    if ev.description: lines.append(f"Описание: {ev.description}")
    return "\n".join(lines)


def project_permissions(project, user_id, global_role, membership):
    is_admin = global_role == "admin"
    is_owner = user_id is not None and project.owner_id == user_id
    project_role = None
    if is_owner:
        project_role = "manager"
    elif membership:
        project_role = membership.role
    can_manage = is_admin or is_owner or project_role == "manager"
    can_edit = can_manage or project_role == "editor"
    can_delete = is_admin or is_owner
    can_upload = can_edit
    return {
        "is_admin": is_admin,
        "is_owner": is_owner,
        "project_role": project_role,
        "can_manage": can_manage,
        "can_edit": can_edit,
        "can_delete": can_delete,
        "can_upload": can_upload,
    }


def workshop_permissions(workshop, user_id, global_role):
    is_admin = global_role in ("admin", "professor")
    is_lead = user_id is not None and workshop.lead_id == user_id
    can_manage = is_admin or is_lead
    return {
        "is_admin": global_role == "admin",
        "is_lead": is_lead,
        "can_manage": can_manage,
        "can_delete": global_role == "admin" or is_lead,
    }


def _ws_registration(db_session, workshop_id, user_id):
    if not user_id:
        return None
    return db_session.exec(
        select(WorkshopRegistration)
        .where(WorkshopRegistration.workshop_id == workshop_id)
        .where(WorkshopRegistration.user_id == user_id)
    ).first()


def _ws_session_helpers(db_session, workshop_id):
    return db_session.exec(
        select(WorkshopSession)
        .where(WorkshopSession.workshop_id == workshop_id)
        .order_by(WorkshopSession.start_time)
    ).all()


def _ws_count_registered(db_session, workshop_id):
    regs = db_session.exec(
        select(WorkshopRegistration)
        .where(WorkshopRegistration.workshop_id == workshop_id)
        .where(WorkshopRegistration.status.in_(("registered", "attended")))
    ).all()
    return len(regs)


def get_all_tags(db_session):
    projects = db_session.exec(select(Project)).all()
    tags = set()
    for p in projects:
        if p.tags:
            for t in p.tags.split(","):
                t = t.strip().lower()
                if t: tags.add(t)
    return sorted(tags)


def resolve_gitea_repo(form_data, current_url=None, current_repo=None):
    raw_repo = (form_data.get("gitea_repo") or "").strip() or None
    raw_url = (form_data.get("gitea_url") or "").strip() or None
    if raw_repo:
        raw_repo = raw_repo.strip("/")
        if "/" in raw_repo:
            return raw_repo
    if raw_url:
        parsed = gitea_api.extract_repo_from_url(raw_url)
        if parsed:
            return parsed
    return None


def get_user_subscription(db_session, user):
    if not user:
        return None
    if not user.id and not user.email:
        return None
    conds = []
    if user.id:
        conds.append(EventSubscriber.user_id == user.id)
    if user.email:
        conds.append(EventSubscriber.email == user.email)
    if not conds:
        return None
    return db_session.exec(select(EventSubscriber).where(or_(*conds))).first()


# ══════════════════════════════════════════════════════════════════════
# КОНСТАНТЫ
# ══════════════════════════════════════════════════════════════════════

STATUS_LABELS = {
    "free": "Свободен / Вне расписания",
    "on_place": "На месте",
    "away": "Вне вуза",
    "cancelled": "Отменено",
}

PROJECT_ROLE_RANK = {"viewer": 1, "editor": 2, "manager": 3}

TASK_STATUSES = ["backlog", "todo", "in_progress", "review", "done"]
TASK_STATUS_LABELS = {
    "backlog": "Backlog",
    "todo": "To Do",
    "in_progress": "In Progress",
    "review": "Review",
    "done": "Done",
}
TASK_PRIORITIES = ["low", "medium", "high", "critical"]

WORKSHOP_CATEGORIES = ["soldering", "embroidery", "embedded", "linux", "other"]
WORKSHOP_CATEGORY_LABELS = {
    "soldering": "Пайка",
    "embroidery": "Бисероплетение",
    "embedded": "Embedded",
    "linux": "Linux",
    "other": "Другое",
}
WORKSHOP_DIFFICULTIES = ["beginner", "intermediate", "advanced"]
WORKSHOP_DIFFICULTY_LABELS = {
    "beginner": "Новичок",
    "intermediate": "Средний",
    "advanced": "Продвинутый",
}
WORKSHOP_STATUSES = ["draft", "published", "archived"]
WORKSHOP_STATUS_LABELS = {
    "draft": "Черновик",
    "published": "Опубликован",
    "archived": "В архиве",
}
WORKSHOP_VISIBILITIES = ["public", "internal"]
WORKSHOP_VISIBILITY_LABELS = {
    "public": "Публичный",
    "internal": "Внутренний",
}


# ══════════════════════════════════════════════════════════════════════
# НАСТРОЙКА ПРИЛОЖЕНИЯ И СТАРТ
# ══════════════════════════════════════════════════════════════════════

UPLOAD_FOLDER = '/var/lib/gitea/portal-files'
app.config['UPLOAD_FOLDER'] = UPLOAD_FOLDER
app.config['MAX_CONTENT_LENGTH'] = 100 * 1024 * 1024

with app.app_context():
    init_db()
    with Session(engine) as db_session:
        status = db_session.exec(select(GlobalStatus)).first()
        if not status:
            db_session.add(GlobalStatus(status="free", message="Вне расписания"))
            db_session.commit()


@app.before_request
def validate_session():
    if "session_id" in session:
        with Session(engine) as db_session:
            db_sess = db_session.exec(select(UserSession).where(UserSession.session_token == session["session_id"])).first()
            if not db_sess:
                session.clear()
                return redirect(url_for("login"))


# ══════════════════════════════════════════════════════════════════════
# EMAIL + УВЕДОМЛЕНИЯ (in-app)
# ══════════════════════════════════════════════════════════════════════

def send_email(to_email, subject, body):
    if not config.SMTP_SERVER:
        print("\n" + "="*60, flush=True)
        print(f"📧 EMAIL ДЛЯ: {to_email}", flush=True)
        print(f"Тема: {subject}", flush=True)
        print(body, flush=True)
        print("="*60 + "\n", flush=True)
        return True
    try:
        msg = MIMEMultipart()
        msg['From'] = config.SMTP_FROM
        msg['To'] = to_email
        msg['Subject'] = subject
        msg.attach(MIMEText(body, 'plain'))
        server = smtplib.SMTP(config.SMTP_SERVER, config.SMTP_PORT)
        server.starttls()
        server.login(config.SMTP_USER, config.SMTP_PASSWORD)
        server.send_message(msg)
        server.quit()
        return True
    except Exception as e:
        print(f"Ошибка отправки email: {e}", flush=True)
        return False


def notify_user(user_id, title, body=None, link_url=None, kind="info"):
    if not user_id:
        return
    try:
        with Session(engine) as s:
            s.add(Notification(user_id=user_id, title=title, body=body, link_url=link_url, kind=kind))
            s.commit()
    except Exception as e:
        print(f"[notify_user] {e}", flush=True)


def notify_users(user_ids, title, body=None, link_url=None, kind="info"):
    for uid in set(uid for uid in user_ids if uid):
        notify_user(uid, title, body, link_url, kind)


def _notify_subscribers_sync(subject, body, kind):
    try:
        with Session(engine) as db_session:
            subscribers = db_session.exec(
                select(EventSubscriber).where(EventSubscriber.is_confirmed == True)
            ).all()
        for sub in subscribers:
            if kind == "status" and not sub.notify_status: continue
            if kind == "event" and not sub.notify_events: continue
            unsubscribe_url = f"https://portal.morozovka.space/unsubscribe/{sub.unsubscribe_token}"
            full_body = (
                body + "\n\n---\n"
                + "Открыть расписание: https://portal.morozovka.space/schedule\n"
                + f"Отписаться: {unsubscribe_url}\n"
            )
            send_email(sub.email, subject, full_body)
    except Exception as e:
        print(f"[notify] Ошибка рассылки: {e}", flush=True)


def notify_subscribers(subject, body, kind):
    threading.Thread(target=_notify_subscribers_sync, args=(subject, body, kind), daemon=True).start()


# ══════════════════════════════════════════════════════════════════════
# БАЗОВЫЕ РОУТЫ
# ══════════════════════════════════════════════════════════════════════

@app.route("/healthz")
def healthz():
    try:
        from sqlalchemy import text
        with engine.connect() as conn:
            conn.execute(text("SELECT 1"))
        return jsonify({
            "status": "ok",
            "db": "ok",
            "llm": "enabled" if llm_assistant.is_enabled() else "disabled",
        })
    except Exception as e:
        return jsonify({"status": "error", "db": str(e)}), 503


@app.route("/")
def index():
    return render_template("index.html", username=session.get("username"))


@app.route("/api/public-status")
def api_public_status():
    with Session(engine) as db_session:
        s = db_session.exec(select(GlobalStatus)).first()
        if not s:
            return jsonify({"status": "free", "delay_minutes": 0, "message": None})
        return jsonify({
            "status": s.status,
            "delay_minutes": s.delay_minutes or 0,
            "message": s.message,
            "updated_at": s.updated_at.isoformat() if s.updated_at else None,
        })


# ══════════════════════════════════════════════════════════════════════
# УВЕДОМЛЕНИЯ — API
# ══════════════════════════════════════════════════════════════════════

@app.route("/api/notifications")
@login_required
def api_notifications_list():
    uid = session.get("user_id")
    with Session(engine) as s:
        items = s.exec(
            select(Notification).where(Notification.user_id == uid)
            .order_by(Notification.created_at.desc()).limit(20)
        ).all()
        unread = s.exec(
            select(Notification).where(Notification.user_id == uid).where(Notification.is_read == False)
        ).all()
        return jsonify({
            "items": [{
                "id": n.id, "title": n.title, "body": n.body, "link_url": n.link_url,
                "kind": n.kind, "is_read": n.is_read,
                "created_at": n.created_at.isoformat() + "Z",
            } for n in items],
            "unread": len(unread),
        })


@app.route("/api/notifications/count")
@login_required
def api_notifications_count():
    uid = session.get("user_id")
    with Session(engine) as s:
        unread = s.exec(
            select(Notification).where(Notification.user_id == uid).where(Notification.is_read == False)
        ).all()
    return jsonify({"unread": len(unread)})


@app.route("/api/notifications/<int:nid>/read", methods=["POST"])
@login_required
def api_notifications_read(nid):
    uid = session.get("user_id")
    with Session(engine) as s:
        n = s.get(Notification, nid)
        if not n or n.user_id != uid:
            return jsonify({"ok": False}), 403
        n.is_read = True
        s.add(n)
        s.commit()
    return jsonify({"ok": True})


@app.route("/api/notifications/read-all", methods=["POST"])
@login_required
def api_notifications_read_all():
    uid = session.get("user_id")
    with Session(engine) as s:
        for n in s.exec(select(Notification).where(Notification.user_id == uid).where(Notification.is_read == False)).all():
            n.is_read = True
            s.add(n)
        s.commit()
    return jsonify({"ok": True})


@app.route("/notifications")
@login_required
def notifications_page():
    uid = session.get("user_id")
    with Session(engine) as s:
        items = s.exec(
            select(Notification).where(Notification.user_id == uid)
            .order_by(Notification.created_at.desc()).limit(100)
        ).all()
    return render_template("notifications_page.html", notifications=items)


# ══════════════════════════════════════════════════════════════════════
# АУТЕНТИФИКАЦИЯ
# ══════════════════════════════════════════════════════════════════════

@app.route("/register", methods=["GET", "POST"])
def register():
    if request.method == "POST":
        username = request.form.get("username")
        email = request.form.get("email")
        password = request.form.get("password")
        full_name = request.form.get("full_name")
        organization = request.form.get("organization")
        with Session(engine) as db_session:
            if db_session.exec(select(User).where(User.username == username)).first():
                return render_template("register.html", error="Логин уже занят")
            if db_session.exec(select(User).where(User.email == email)).first():
                return render_template("register.html", error="Email уже используется")
            new_user = User(
                username=username, email=email,
                password_hash=generate_password_hash(password),
                full_name=full_name, organization=organization,
                role="student", is_verified=True,
            )
            db_session.add(new_user)
            db_session.commit()
        return render_template("login.html", msg="Регистрация успешна. Можете войти.")
    return render_template("register.html")


@app.route("/verify_email/<token>")
def verify_email(token):
    try: email = serializer.loads(token, salt='email-confirm', max_age=86400)
    except Exception: return "Ссылка недействительна или устарела.", 400
    with Session(engine) as db_session:
        user = db_session.exec(select(User).where(User.email == email)).first()
        if user:
            user.is_verified = True
            db_session.add(user)
            db_session.commit()
            return redirect(url_for("login", msg="Почта подтверждена! Теперь можно войти."))
    return "Пользователь не найден.", 404


@app.route("/login", methods=["GET", "POST"])
def login():
    if request.method == "POST":
        username = request.form.get("username")
        password = request.form.get("password")
        with Session(engine) as db_session:
            user = db_session.exec(select(User).where(User.username == username)).first()
            if not user or not user.password_hash or not check_password_hash(user.password_hash, password):
                return render_template("login.html", error="Неверный логин или пароль")
            if not user.is_verified:
                return render_template("login.html", error="Подтвердите почту перед входом")
            session_token = str(uuid.uuid4())
            db_session.add(UserSession(
                session_token=session_token, user_id=user.id,
                ip_address=request.remote_addr, user_agent=request.user_agent.string,
            ))
            db_session.commit()
            session["user_id"] = user.id
            session["username"] = user.username
            session["role"] = user.role
            session["session_id"] = session_token
            return redirect(url_for("index"))
    return render_template("login.html", msg=request.args.get("msg"))


@app.route("/login/gitea")
def login_gitea():
    gitea_auth_url = (
        f"{config.GITEA_PUBLIC_URL}/login/oauth/authorize"
        f"?client_id={config.GITEA_CLIENT_ID}&response_type=code"
        f"&redirect_uri={config.GITEA_REDIRECT_URI}"
        f"&scope=read:user"
    )
    return redirect(gitea_auth_url)


@app.route("/auth/callback")
def auth_callback():
    code = request.args.get("code")
    if not code: return "Ошибка авторизации Gitea", 400
    token = auth.get_gitea_token(code)
    if not token: return "Ошибка токена Gitea", 400
    gitea_user = auth.get_gitea_user(token)
    if not gitea_user: return "Ошибка профиля Gitea", 400
    with Session(engine) as db_session:
        user = db_session.exec(select(User).where(User.gitea_id == gitea_user["id"])).first()
        if not user:
            user = db_session.exec(select(User).where(User.email == gitea_user.get("email"))).first()
            if user:
                user.gitea_id = gitea_user["id"]
            else:
                existing_admin = db_session.exec(select(User).where(User.role == "admin")).first()
                bootstrap_role = "admin" if not existing_admin else "student"
                user = User(
                    gitea_id=gitea_user["id"], username=gitea_user["login"],
                    full_name=gitea_user.get("full_name"), email=gitea_user.get("email"),
                    role=bootstrap_role, is_verified=True,
                )
                db_session.add(user)
            db_session.commit()
        session_token = str(uuid.uuid4())
        db_session.add(UserSession(
            session_token=session_token, user_id=user.id,
            ip_address=request.remote_addr, user_agent=request.user_agent.string,
        ))
        db_session.commit()
        session["user_id"] = user.id
        session["username"] = user.username
        session["role"] = user.role
        session["session_id"] = session_token
    return redirect(url_for("index"))


@app.route("/logout")
def logout():
    if "session_id" in session:
        with Session(engine) as db_session:
            db_sess = db_session.exec(select(UserSession).where(UserSession.session_token == session["session_id"])).first()
            if db_sess:
                db_session.delete(db_sess)
                db_session.commit()
    session.clear()
    return redirect(url_for("index"))


@app.route("/forgot_password", methods=["GET", "POST"])
def forgot_password():
    if request.method == "POST":
        email = request.form.get("email")
        with Session(engine) as db_session:
            user = db_session.exec(select(User).where(User.email == email)).first()
            if user:
                token = serializer.dumps(email, salt='password-reset')
                reset_url = url_for('reset_password', token=token, _external=True).replace("127.0.0.1:8000", "portal.morozovka.space").replace("http://", "https://")
                send_email(email, "Сброс пароля", f"Для сброса пароля перейди по ссылке:\n{reset_url}\n")
        return render_template("login.html", msg="Если такой email есть, инструкция отправлена.")
    return render_template("forgot_password.html")


@app.route("/reset_password/<token>", methods=["GET", "POST"])
def reset_password(token):
    try: email = serializer.loads(token, salt='password-reset', max_age=3600)
    except Exception: return "Ссылка недействительна или устарела.", 400
    if request.method == "POST":
        with Session(engine) as db_session:
            user = db_session.exec(select(User).where(User.email == email)).first()
            if user:
                user.password_hash = generate_password_hash(request.form.get("password"))
                db_session.add(user)
                db_session.commit()
                return redirect(url_for("login", msg="Пароль успешно изменен!"))
    return render_template("reset_password.html", token=token)


@app.route("/sessions")
@login_required
def sessions_list():
    with Session(engine) as db_session:
        sessions = db_session.exec(
            select(UserSession).where(UserSession.user_id == session.get("user_id"))
            .order_by(UserSession.created_at.desc())
        ).all()
    return render_template("sessions.html", sessions=sessions, current_token=session.get("session_id"))


@app.route("/sessions/logout_all", methods=["POST"])
@login_required
def logout_all():
    with Session(engine) as db_session:
        for s in db_session.exec(select(UserSession).where(UserSession.user_id == session.get("user_id"))).all():
            db_session.delete(s)
        db_session.commit()
    session.clear()
    return redirect(url_for("login", msg="Вы вышли со всех устройств."))


@app.route("/profile")
@login_required
def profile():
    with Session(engine) as db_session:
        user = db_session.get(User, session.get("user_id"))
        subscription = get_user_subscription(db_session, user)
    return render_template("profile.html", user=user, subscription=subscription)


# ══════════════════════════════════════════════════════════════════════
# ПОДПИСКИ
# ══════════════════════════════════════════════════════════════════════

@app.route("/subscribe/toggle", methods=["POST"])
@login_required
def subscribe_toggle():
    action = request.form.get("action")
    notify_status = request.form.get("notify_status") == "on"
    notify_events = request.form.get("notify_events") == "on"
    next_url = request.form.get("next") or url_for("profile")
    if not next_url.startswith("/"): next_url = url_for("profile")
    with Session(engine) as db_session:
        user = db_session.get(User, session.get("user_id"))
        if not user or not user.email:
            return redirect(next_url)
        existing = get_user_subscription(db_session, user)
        if action == "unsubscribe":
            if existing:
                db_session.delete(existing)
                db_session.commit()
            return redirect(next_url)
        if existing:
            existing.email = user.email
            existing.user_id = user.id
            existing.notify_status = notify_status
            existing.notify_events = notify_events
            existing.is_confirmed = True
            existing.confirm_token = None
            db_session.add(existing)
        else:
            db_session.add(EventSubscriber(
                email=user.email, user_id=user.id,
                unsubscribe_token=str(uuid.uuid4()),
                is_confirmed=True, confirm_token=None,
                notify_status=notify_status, notify_events=notify_events,
            ))
        db_session.commit()
    return redirect(next_url)


@app.route("/subscribe/confirm/<token>")
def subscribe_confirm(token):
    with Session(engine) as db_session:
        sub = db_session.exec(select(EventSubscriber).where(EventSubscriber.confirm_token == token)).first()
        if not sub:
            return render_template("subscribe_status.html", title="Ссылка недействительна",
                                   message="Возможно, ссылка уже использована или устарела.", ok=False)
        sub.is_confirmed = True
        sub.confirm_token = None
        db_session.add(sub)
        db_session.commit()
        return render_template("subscribe_status.html", title="Подписка подтверждена!",
                               message=f"Вы будете получать уведомления на {sub.email}.",
                               ok=True, unsubscribe_token=sub.unsubscribe_token)


@app.route("/unsubscribe/<token>", methods=["GET", "POST"])
def unsubscribe(token):
    with Session(engine) as db_session:
        sub = db_session.exec(select(EventSubscriber).where(EventSubscriber.unsubscribe_token == token)).first()
        if not sub:
            return render_template("subscribe_status.html", title="Ссылка недействительна",
                                   message="Такой подписки нет.", ok=False)
        if request.method == "POST":
            db_session.delete(sub)
            db_session.commit()
            return render_template("subscribe_status.html", title="Вы отписаны",
                                   message="Больше не будет присылать уведомления.", ok=True)
        return render_template("subscribe_status.html", title="Отписаться от уведомлений?",
                               message=f"Вы перестанете получать письма на {sub.email}.",
                               ok=True, show_confirm_form=True,
                               confirm_action=url_for("unsubscribe", token=token))


# ══════════════════════════════════════════════════════════════════════
# РАСПИСАНИЕ
# ══════════════════════════════════════════════════════════════════════

@app.route("/schedule")
def public_schedule():
    with Session(engine) as db_session:
        current_status = db_session.exec(select(GlobalStatus)).first()
        now = datetime.now(timezone.utc)
        events = db_session.exec(
            select(Event).where(Event.is_public == True)
            .where(Event.start_time >= now - timedelta(days=180))
            .where(Event.start_time <= now + timedelta(days=365))
            .order_by(Event.start_time)
        ).all()
        my_subscription = None
        current_user = None
        if session.get("user_id"):
            current_user = db_session.get(User, session["user_id"])
            if current_user:
                my_subscription = get_user_subscription(db_session, current_user)
    events_json = [
        {"id": e.id, "title": e.title, "type": e.event_type,
         "start": to_msk(e.start_time).isoformat(), "end": to_msk(e.end_time).isoformat(),
         "location": e.location, "description": e.description}
        for e in events
    ]
    return render_template("schedule.html", status=current_status, events_json=events_json,
                           my_subscription=my_subscription, current_user=current_user,
                           msg=request.args.get("msg"), error=request.args.get("error"))


@app.route("/schedule/export.ics")
def export_ics():
    with Session(engine) as db_session:
        events = db_session.exec(select(Event).where(Event.is_public == True)).all()
    cal = Calendar()
    cal.add('prodid', '-//Morozovka Portal//mxm.dk//')
    cal.add('version', '2.0')
    for ev in events:
        ievent = ICalEvent()
        ievent.add('summary', ev.title)
        ievent.add('dtstart', ev.start_time.astimezone(pytz.utc))
        ievent.add('dtend', ev.end_time.astimezone(pytz.utc))
        if ev.location: ievent.add('location', ev.location)
        if ev.description: ievent.add('description', ev.description)
        cal.add_component(ievent)
    response = make_response(cal.to_ical())
    response.headers["Content-Disposition"] = "attachment; filename=morozovka_schedule.ics"
    response.headers["Content-Type"] = "text/calendar; charset=utf-8"
    return response


@app.route("/api/assistant", methods=["POST"])
def api_assistant():
    data = request.get_json() or {}
    message = (data.get("message") or "").strip()
    if not message:
        return jsonify({"error": "Нет сообщения"}), 400
    history = data.get("history") or []

    if llm_assistant.is_enabled():
        try:
            reply = llm_assistant.chat(message, history)
            if reply:
                return jsonify({"reply": reply, "source": "llm"})
        except Exception as e:
            print(f"[llm] fallback to regex: {e}", flush=True)

    return jsonify({"reply": assistant.get_response(message), "source": "regex"})


@app.route("/admin/schedule")
@require_role(["admin", "professor"])
def admin_schedule():
    with Session(engine) as db_session:
        current_status = db_session.exec(select(GlobalStatus)).first()
        events = db_session.exec(select(Event).order_by(Event.start_time.desc()).limit(50)).all()
    return render_template("admin_schedule.html", status=current_status, events=events)


@app.route("/admin/schedule/status", methods=["POST"])
@require_role(["admin", "professor"])
def update_status():
    status_val = request.form.get("status")
    delay = int(request.form.get("delay_minutes") or 0)
    message = request.form.get("message")
    with Session(engine) as db_session:
        current_status = db_session.exec(select(GlobalStatus)).first()
        if current_status:
            old_label = status_label(current_status.status, current_status.delay_minutes)
            current_status.status = status_val
            current_status.delay_minutes = delay
            current_status.message = message
            current_status.updated_at = datetime.now(timezone.utc)
            db_session.add(current_status)
            db_session.commit()
            new_label = status_label(status_val, delay)
            subject = f"[Расписание] Статус: {new_label}"
            body = f"Новый статус: {new_label}\nБыло: {old_label}\n"
            if message: body += f"Сообщение: {message}\n"
            body += f"Обновлено: {datetime.now(MSK).strftime('%d.%m.%Y %H:%M')}\n"
            notify_subscribers(subject, body, kind="status")
    return redirect(url_for("admin_schedule"))


@app.route("/admin/schedule/event/add", methods=["POST"])
@require_role(["admin", "professor"])
def add_event():
    title = request.form.get("title")
    event_type = request.form.get("event_type")
    start_time = parse_datetime(request.form.get("start_time"))
    end_time = parse_datetime(request.form.get("end_time"))
    with Session(engine) as db_session:
        ev = Event(title=title, event_type=event_type, start_time=start_time, end_time=end_time,
                   location=request.form.get("location"), description=request.form.get("description"),
                   is_public=request.form.get("is_public") == "on")
        db_session.add(ev)
        db_session.commit()
        db_session.refresh(ev)
        if ev.is_public:
            notify_subscribers(f"[Расписание] Новое событие: {ev.title}",
                               "Добавлено новое событие в расписание.\n\n" + event_summary_text(ev),
                               kind="event")
    return redirect(url_for("admin_schedule"))


@app.route("/admin/schedule/event/<int:event_id>/edit", methods=["GET", "POST"])
@require_role(["admin", "professor"])
def edit_event(event_id):
    with Session(engine) as db_session:
        event = db_session.get(Event, event_id)
        if not event: return "Событие не найдено", 404
        if request.method == "POST":
            event.title = request.form.get("title")
            event.event_type = request.form.get("event_type")
            event.start_time = parse_datetime(request.form.get("start_time"))
            event.end_time = parse_datetime(request.form.get("end_time"))
            event.location = request.form.get("location")
            event.description = request.form.get("description")
            event.is_public = request.form.get("is_public") == "on"
            event.manually_edited = True
            db_session.add(event)
            db_session.commit()
            if event.is_public:
                notify_subscribers(f"[Расписание] Изменено: {event.title}",
                                   "Событие в расписании изменено.\n\n" + event_summary_text(event),
                                   kind="event")
            return redirect(url_for("admin_schedule"))
    return render_template("admin_event_edit.html", event=event)


@app.route("/admin/schedule/event/<int:event_id>/delete", methods=["POST"])
@require_role(["admin", "professor"])
def delete_event(event_id):
    with Session(engine) as db_session:
        event = db_session.get(Event, event_id)
        if event:
            title_snapshot = event.title
            start_snapshot = event.start_time
            was_public = event.is_public
            db_session.delete(event)
            db_session.commit()
            if was_public:
                body = (
                    f"Событие отменено/удалено из расписания.\n\n"
                    f"Название: {title_snapshot}\n"
                    f"Было запланировано: {to_msk(start_snapshot).strftime('%d.%m.%Y %H:%M')}\n"
                )
                notify_subscribers(f"[Расписание] Удалено: {title_snapshot}", body, kind="event")
    return redirect(url_for("admin_schedule"))


@app.route("/admin/schedule/import", methods=["GET", "POST"])
@require_role(["admin", "professor"])
def import_ics():
    if request.method == "POST":
        if 'file' not in request.files: return "Файл не загружен", 400
        file = request.files['file']
        if file.filename == '': return "Файл не выбран", 400
        if file and file.filename.endswith('.ics'):
            try:
                cal = Calendar.from_ical(file.read())
                count = 0
                with Session(engine) as db_session:
                    for component in cal.walk():
                        if component.name == "VEVENT":
                            summary = str(component.get('summary', 'Без названия'))
                            dtstart_prop = component.get('dtstart')
                            dtend_prop = component.get('dtend')
                            if not dtstart_prop or not dtend_prop: continue
                            dtstart = dtstart_prop.dt
                            dtend = dtend_prop.dt
                            if not isinstance(dtstart, datetime):
                                dtstart = datetime.combine(dtstart, datetime.min.time())
                            if not isinstance(dtend, datetime):
                                dtend = datetime.combine(dtend, datetime.min.time())
                            if dtstart.tzinfo is None: dtstart = dtstart.replace(tzinfo=timezone.utc)
                            if dtend.tzinfo is None: dtend = dtend.replace(tzinfo=timezone.utc)
                            new_event = Event(
                                title=summary, event_type='lecture',
                                start_time=dtstart.astimezone(timezone.utc),
                                end_time=dtend.astimezone(timezone.utc),
                                location=str(component.get('location', '')),
                                description=str(component.get('description', '')),
                                is_public=True
                            )
                            db_session.add(new_event)
                            count += 1
                    db_session.commit()
                if count > 0:
                    notify_subscribers(f"[Расписание] Импортировано событий: {count}",
                                       f"В расписание добавлено событий: {count}.\n", kind="event")
                return redirect(url_for("admin_schedule"))
            except Exception as e:
                return f"Ошибка при чтении файла .ics: {e}", 400
    return render_template("admin_schedule_import.html")


# ══════════════════════════════════════════════════════════════════════
# ПРОЕКТЫ
# ══════════════════════════════════════════════════════════════════════

@app.route("/projects")
def projects_list():
    user_role = session.get("role")
    user_id = session.get("user_id")
    current_tag = (request.args.get("tag") or "").strip().lower()
    current_status = (request.args.get("status") or "").strip()
    with Session(engine) as db_session:
        all_projects = db_session.exec(select(Project).order_by(Project.created_at.desc())).all()
        member_map = {}
        if user_id:
            for m in db_session.exec(select(ProjectMember).where(ProjectMember.user_id == user_id)).all():
                member_map[m.project_id] = m.role
        all_tags = get_all_tags(db_session)
    filtered = []
    for p in all_projects:
        if p.visibility == "public":
            filtered.append(p)
        elif p.visibility == "internal" and user_id:
            filtered.append(p)
        elif p.visibility == "private" and user_id and (p.owner_id == user_id or p.id in member_map or user_role == "admin"):
            filtered.append(p)
    if current_status:
        filtered = [p for p in filtered if p.status == current_status]
    if current_tag:
        def has_tag(p):
            if not p.tags: return False
            return current_tag in [t.strip().lower() for t in p.tags.split(",")]
        filtered = [p for p in filtered if has_tag(p)]
    return render_template("projects.html", projects=filtered, role=user_role, user_id=user_id,
                           member_map=member_map, all_tags=all_tags,
                           current_tag=current_tag, current_status=current_status)


@app.route("/projects/new", methods=["GET", "POST"])
@require_role(["admin", "professor", "lead"])
def project_new():
    if request.method == "POST":
        with Session(engine) as db_session:
            new_proj = Project(
                title=request.form.get("title"),
                description=request.form.get("description"),
                status=request.form.get("status"),
                visibility=request.form.get("visibility"),
                gitea_url=(request.form.get("gitea_url") or "").strip() or None,
                gitea_repo=resolve_gitea_repo(request.form),
                tags=normalize_tags(request.form.get("tags")),
                start_date=(request.form.get("start_date") or "").strip() or None,
                end_date=(request.form.get("end_date") or "").strip() or None,
                contact_person=(request.form.get("contact_person") or "").strip() or None,
                owner_id=session.get("user_id"),
            )
            db_session.add(new_proj)
            db_session.flush()
            proj_id = new_proj.id
            db_session.add(ProjectMember(project_id=proj_id, user_id=session.get("user_id"), role="manager"))
            db_session.commit()
        return redirect(url_for("project_detail", project_id=proj_id))
    return render_template("project_form.html", project=None, is_edit=False)


@app.route("/projects/<int:project_id>")
def project_detail(project_id):
    user_id = session.get("user_id")
    user_role = session.get("role")
    with Session(engine) as db_session:
        proj = db_session.get(Project, project_id)
        if not proj: return "Проект не найден", 404
        membership = None
        if user_id:
            membership = db_session.exec(
                select(ProjectMember).where(ProjectMember.project_id == project_id).where(ProjectMember.user_id == user_id)
            ).first()
        perms = project_permissions(proj, user_id, user_role, membership)
        if proj.visibility == "private" and not perms["is_admin"] and not perms["is_owner"] and not membership:
            return "403: Это приватный проект", 403
        if proj.visibility == "internal" and not user_id:
            return redirect(url_for("login"))
        members = db_session.exec(
            select(ProjectMember, User).join(User, ProjectMember.user_id == User.id)
            .where(ProjectMember.project_id == project_id).order_by(User.username)
        ).all()
        files = db_session.exec(
            select(PortalFile, User.username).join(User, PortalFile.uploaded_by == User.id)
            .where(PortalFile.project_id == project_id).order_by(PortalFile.uploaded_at.desc())
        ).all()
        task_counts = {s: 0 for s in TASK_STATUSES}
        for t in db_session.exec(select(ProjectTask).where(ProjectTask.project_id == project_id)).all():
            if t.status in task_counts: task_counts[t.status] += 1
    return render_template("project_detail.html", project=proj, members=members, files=files,
                           perms=perms, user_id=user_id, role=user_role,
                           active_tab="overview", task_counts=task_counts)


@app.route("/projects/<int:project_id>/gitea-stats")
def project_gitea_stats(project_id):
    with Session(engine) as db_session:
        proj = db_session.get(Project, project_id)
        if not proj:
            return jsonify({"ok": False, "error": "not_found", "message": "Проект не найден"}), 404
        user_id = session.get("user_id")
        user_role = session.get("role")
        membership = None
        if user_id:
            membership = db_session.exec(
                select(ProjectMember).where(ProjectMember.project_id == project_id).where(ProjectMember.user_id == user_id)
            ).first()
        perms = project_permissions(proj, user_id, user_role, membership)
        if proj.visibility == "private" and not perms["is_admin"] and not perms["is_owner"] and not membership:
            return jsonify({"ok": False, "error": "forbidden"}), 403
        repo = proj.gitea_repo
        if not repo and proj.gitea_url:
            repo = gitea_api.extract_repo_from_url(proj.gitea_url)
    if not repo:
        return jsonify({"ok": False, "error": "no_repo", "message": "У проекта не указан репозиторий."})
    return jsonify(gitea_api.get_project_stats(repo))


@app.route("/projects/<int:project_id>/edit", methods=["GET", "POST"])
@login_required
def project_edit(project_id):
    with Session(engine) as db_session:
        proj = db_session.get(Project, project_id)
        if not proj: return "Проект не найден", 404
        membership = db_session.exec(
            select(ProjectMember).where(ProjectMember.project_id == project_id).where(ProjectMember.user_id == session.get("user_id"))
        ).first()
        perms = project_permissions(proj, session.get("user_id"), session.get("role"), membership)
        if not perms["can_manage"]:
            return "403: У вас нет прав на редактирование проекта", 403
        if request.method == "POST":
            proj.title = request.form.get("title")
            proj.description = request.form.get("description")
            proj.status = request.form.get("status")
            proj.visibility = request.form.get("visibility")
            proj.gitea_url = (request.form.get("gitea_url") or "").strip() or None
            proj.gitea_repo = resolve_gitea_repo(request.form, proj.gitea_url, proj.gitea_repo)
            proj.tags = normalize_tags(request.form.get("tags"))
            proj.start_date = (request.form.get("start_date") or "").strip() or None
            proj.end_date = (request.form.get("end_date") or "").strip() or None
            proj.contact_person = (request.form.get("contact_person") or "").strip() or None
            db_session.add(proj)
            db_session.commit()
            return redirect(url_for("project_detail", project_id=proj.id))
    return render_template("project_form.html", project=proj, is_edit=True)


@app.route("/projects/<int:project_id>/members/add", methods=["POST"])
@login_required
def project_add_member(project_id):
    username = (request.form.get("username") or "").strip()
    role = request.form.get("role") or "viewer"
    if role not in PROJECT_ROLE_RANK: role = "viewer"
    with Session(engine) as db_session:
        proj = db_session.get(Project, project_id)
        if not proj: return "Проект не найден", 404
        membership = db_session.exec(
            select(ProjectMember).where(ProjectMember.project_id == project_id).where(ProjectMember.user_id == session.get("user_id"))
        ).first()
        perms = project_permissions(proj, session.get("user_id"), session.get("role"), membership)
        if not perms["can_manage"]: return "403: Нет прав", 403
        user_to_add = db_session.exec(select(User).where(User.username == username)).first()
        if not user_to_add: return redirect(url_for("project_detail", project_id=project_id))
        existing = db_session.exec(
            select(ProjectMember).where(ProjectMember.project_id == project_id).where(ProjectMember.user_id == user_to_add.id)
        ).first()
        if not existing:
            db_session.add(ProjectMember(project_id=project_id, user_id=user_to_add.id, role=role))
            db_session.commit()
            notify_user(user_to_add.id,
                        f"Вас добавили в проект «{proj.title}»",
                        f"Роль: {role}",
                        link_url=url_for("project_detail", project_id=project_id),
                        kind="info")
    return redirect(url_for("project_detail", project_id=project_id))


@app.route("/projects/<int:project_id>/members/<int:user_id>/role", methods=["POST"])
@login_required
def project_change_member_role(project_id, user_id):
    new_role = request.form.get("role") or "viewer"
    if new_role not in PROJECT_ROLE_RANK: return "Ошибка: неверная роль", 400
    with Session(engine) as db_session:
        proj = db_session.get(Project, project_id)
        if not proj: return "Проект не найден", 404
        my_membership = db_session.exec(
            select(ProjectMember).where(ProjectMember.project_id == project_id).where(ProjectMember.user_id == session.get("user_id"))
        ).first()
        perms = project_permissions(proj, session.get("user_id"), session.get("role"), my_membership)
        if not perms["can_manage"]: return "403: Нет прав", 403
        if user_id == proj.owner_id: return "Нельзя менять роль владельца", 400
        target = db_session.exec(
            select(ProjectMember).where(ProjectMember.project_id == project_id).where(ProjectMember.user_id == user_id)
        ).first()
        if target:
            target.role = new_role
            db_session.add(target)
            db_session.commit()
    return redirect(url_for("project_detail", project_id=project_id))


@app.route("/projects/<int:project_id>/members/<int:user_id>/remove", methods=["POST"])
@login_required
def project_remove_member(project_id, user_id):
    with Session(engine) as db_session:
        proj = db_session.get(Project, project_id)
        if not proj: return "Проект не найден", 404
        my_membership = db_session.exec(
            select(ProjectMember).where(ProjectMember.project_id == project_id).where(ProjectMember.user_id == session.get("user_id"))
        ).first()
        perms = project_permissions(proj, session.get("user_id"), session.get("role"), my_membership)
        if not perms["can_manage"]: return "403: Нет прав", 403
        if user_id == proj.owner_id: return "Нельзя удалить владельца", 400
        to_remove = db_session.exec(
            select(ProjectMember).where(ProjectMember.project_id == project_id).where(ProjectMember.user_id == user_id)
        ).first()
        if to_remove:
            db_session.delete(to_remove)
            db_session.commit()
    return redirect(url_for("project_detail", project_id=project_id))


@app.route("/projects/<int:project_id>/delete", methods=["POST"])
@login_required
def project_delete(project_id):
    with Session(engine) as db_session:
        proj = db_session.get(Project, project_id)
        if not proj:
            print(f"[project_delete] Проект {project_id} не найден", flush=True)
            return redirect(url_for("projects_list"))
        user_id = session.get("user_id")
        user_role = session.get("role")
        membership = db_session.exec(
            select(ProjectMember).where(ProjectMember.project_id == project_id).where(ProjectMember.user_id == user_id)
        ).first()
        perms = project_permissions(proj, user_id, user_role, membership)
        if not perms["can_delete"]:
            return f"403: Удалять проект может только владелец (id={proj.owner_id}) или админ. Вы — id={user_id}, роль={user_role}.", 403
        try:
            files = db_session.exec(select(PortalFile).where(PortalFile.project_id == project_id)).all()
            for f in files:
                f.project_id = None
                db_session.add(f)
            db_session.flush()
            tasks = db_session.exec(select(ProjectTask).where(ProjectTask.project_id == project_id)).all()
            for t in tasks:
                db_session.delete(t)
            db_session.flush()
            members = db_session.exec(select(ProjectMember).where(ProjectMember.project_id == project_id)).all()
            for m in members:
                db_session.delete(m)
            db_session.flush()
            db_session.delete(proj)
            db_session.commit()
        except Exception as e:
            db_session.rollback()
            print(f"[project_delete] ОШИБКА при удалении {project_id}: {e}", flush=True)
            import traceback
            traceback.print_exc()
            return f"Ошибка удаления: {e}", 500
    return redirect(url_for("projects_list"))


@app.route("/projects/<int:project_id>/files/upload", methods=["POST"])
@login_required
def project_file_upload(project_id):
    with Session(engine) as db_session:
        proj = db_session.get(Project, project_id)
        if not proj: return "Проект не найден", 404
        membership = db_session.exec(
            select(ProjectMember).where(ProjectMember.project_id == project_id).where(ProjectMember.user_id == session.get("user_id"))
        ).first()
        perms = project_permissions(proj, session.get("user_id"), session.get("role"), membership)
        if not perms["can_upload"]:
            return "403: Нет прав на загрузку файлов", 403
    try:
        file = request.files.get('file')
    except Exception as e:
        print(f"[project_file_upload] Ошибка парсинга: {e}", flush=True)
        return "Ошибка разбора запроса", 400
    if not file or file.filename == '':
        return redirect(url_for("project_detail", project_id=project_id))
    original_name = file.filename
    ext = os.path.splitext(original_name)[1]
    stored_name = f"{uuid.uuid4().hex}{ext}"
    filepath = os.path.join(app.config['UPLOAD_FOLDER'], stored_name)
    try:
        file.save(filepath)
        size_bytes = os.path.getsize(filepath)
    except Exception as e:
        print(f"[project_file_upload] Ошибка сохранения: {e}", flush=True)
        return "Ошибка сохранения файла", 500
    try:
        with Session(engine) as db_session:
            db_session.add(PortalFile(
                original_name=original_name, stored_name=stored_name,
                size_bytes=size_bytes, uploaded_by=session.get("user_id"),
                project_id=project_id,
            ))
            db_session.commit()
    except Exception as e:
        print(f"[project_file_upload] Ошибка БД: {e}", flush=True)
        try: os.remove(filepath)
        except Exception: pass
        return "Ошибка записи в БД", 500
    return redirect(url_for("project_detail", project_id=project_id))


# ══════════════════════════════════════════════════════════════════════
# КАНБАН
# ══════════════════════════════════════════════════════════════════════

@app.route("/projects/<int:project_id>/board")
def project_board(project_id):
    user_id = session.get("user_id")
    user_role = session.get("role")
    with Session(engine) as db_session:
        proj = db_session.get(Project, project_id)
        if not proj: return "Проект не найден", 404
        membership = None
        if user_id:
            membership = db_session.exec(
                select(ProjectMember).where(ProjectMember.project_id == project_id).where(ProjectMember.user_id == user_id)
            ).first()
        perms = project_permissions(proj, user_id, user_role, membership)
        if proj.visibility == "private" and not perms["is_admin"] and not perms["is_owner"] and not membership:
            return "403: Это приватный проект", 403
        if proj.visibility == "internal" and not user_id:
            return redirect(url_for("login"))
        members = db_session.exec(
            select(ProjectMember, User).join(User, ProjectMember.user_id == User.id)
            .where(ProjectMember.project_id == project_id).order_by(User.username)
        ).all()
        tasks = db_session.exec(
            select(ProjectTask).where(ProjectTask.project_id == project_id)
            .order_by(ProjectTask.position, ProjectTask.id)
        ).all()
        user_ids = set()
        for t in tasks:
            if t.assignee_id: user_ids.add(t.assignee_id)
            if t.created_by: user_ids.add(t.created_by)
        users_map = {}
        if user_ids:
            for u in db_session.exec(select(User).where(User.id.in_(user_ids))).all():
                users_map[u.id] = u
        columns = {s: [] for s in TASK_STATUSES}
        for t in tasks:
            if t.status in columns:
                columns[t.status].append({
                    "task": t,
                    "assignee": users_map.get(t.assignee_id) if t.assignee_id else None,
                    "author": users_map.get(t.created_by),
                })
        task_counts = {s: len(columns[s]) for s in TASK_STATUSES}
    return render_template("project_board.html",
                           project=proj, members=members, columns=columns,
                           perms=perms, user_id=user_id, role=user_role,
                           active_tab="board", task_counts=task_counts,
                           TASK_STATUSES=TASK_STATUSES, TASK_STATUS_LABELS=TASK_STATUS_LABELS,
                           TASK_PRIORITIES=TASK_PRIORITIES)


@app.route("/projects/<int:project_id>/tasks/new", methods=["POST"])
@login_required
def task_new(project_id):
    with Session(engine) as db_session:
        proj = db_session.get(Project, project_id)
        if not proj: return "Проект не найден", 404
        membership = db_session.exec(
            select(ProjectMember).where(ProjectMember.project_id == project_id).where(ProjectMember.user_id == session.get("user_id"))
        ).first()
        perms = project_permissions(proj, session.get("user_id"), session.get("role"), membership)
        if not perms["can_edit"]:
            return "403: Нет прав", 403
        title = (request.form.get("title") or "").strip()
        if not title:
            return redirect(url_for("project_board", project_id=project_id))
        status = request.form.get("status") or "backlog"
        if status not in TASK_STATUSES: status = "backlog"
        priority = request.form.get("priority") or "medium"
        if priority not in TASK_PRIORITIES: priority = "medium"
        assignee_id = request.form.get("assignee_id")
        assignee_id = int(assignee_id) if assignee_id and assignee_id.isdigit() else None
        max_pos = db_session.exec(
            select(ProjectTask).where(ProjectTask.project_id == project_id).where(ProjectTask.status == status)
        ).all()
        position = max([t.position for t in max_pos], default=-1) + 1
        task = ProjectTask(
            project_id=project_id, title=title,
            description=(request.form.get("description") or "").strip() or None,
            status=status, priority=priority, assignee_id=assignee_id,
            created_by=session.get("user_id"),
            due_date=(request.form.get("due_date") or "").strip() or None,
            position=position,
        )
        db_session.add(task)
        db_session.commit()
        if assignee_id and assignee_id != session.get("user_id"):
            notify_user(assignee_id,
                        f"Вам назначена задача: {title}",
                        f"Проект: {proj.title}",
                        link_url=url_for("project_board", project_id=project_id),
                        kind="info")
    return redirect(url_for("project_board", project_id=project_id))


@app.route("/projects/<int:project_id>/tasks/<int:task_id>/edit", methods=["GET", "POST"])
@login_required
def task_edit(project_id, task_id):
    with Session(engine) as db_session:
        proj = db_session.get(Project, project_id)
        if not proj: return "Проект не найден", 404
        membership = db_session.exec(
            select(ProjectMember).where(ProjectMember.project_id == project_id).where(ProjectMember.user_id == session.get("user_id"))
        ).first()
        perms = project_permissions(proj, session.get("user_id"), session.get("role"), membership)
        if not perms["can_edit"]:
            return "403: Нет прав", 403
        task = db_session.get(ProjectTask, task_id)
        if not task or task.project_id != project_id:
            return "Задача не найдена", 404
        if request.method == "POST":
            old_assignee = task.assignee_id
            task.title = (request.form.get("title") or task.title).strip()
            task.description = (request.form.get("description") or "").strip() or None
            new_status = request.form.get("status") or task.status
            if new_status in TASK_STATUSES: task.status = new_status
            new_priority = request.form.get("priority") or task.priority
            if new_priority in TASK_PRIORITIES: task.priority = new_priority
            assignee = request.form.get("assignee_id")
            new_assignee = int(assignee) if assignee and assignee.isdigit() else None
            task.assignee_id = new_assignee
            task.due_date = (request.form.get("due_date") or "").strip() or None
            task.updated_at = datetime.now(timezone.utc)
            db_session.add(task)
            db_session.commit()
            if new_assignee and new_assignee != old_assignee and new_assignee != session.get("user_id"):
                notify_user(new_assignee,
                            f"Вам назначена задача: {task.title}",
                            f"Проект: {proj.title}",
                            link_url=url_for("project_board", project_id=project_id),
                            kind="info")
            return redirect(url_for("project_board", project_id=project_id))
        members = db_session.exec(
            select(ProjectMember, User).join(User, ProjectMember.user_id == User.id)
            .where(ProjectMember.project_id == project_id).order_by(User.username)
        ).all()
    return render_template("task_edit.html", project=proj, task=task, members=members,
                           TASK_STATUSES=TASK_STATUSES, TASK_STATUS_LABELS=TASK_STATUS_LABELS,
                           TASK_PRIORITIES=TASK_PRIORITIES)


@app.route("/projects/<int:project_id>/tasks/<int:task_id>/delete", methods=["POST"])
@login_required
def task_delete(project_id, task_id):
    with Session(engine) as db_session:
        proj = db_session.get(Project, project_id)
        if not proj: return "Проект не найден", 404
        membership = db_session.exec(
            select(ProjectMember).where(ProjectMember.project_id == project_id).where(ProjectMember.user_id == session.get("user_id"))
        ).first()
        perms = project_permissions(proj, session.get("user_id"), session.get("role"), membership)
        if not perms["can_manage"]:
            return "403: Удалять задачи может только менеджер проекта", 403
        task = db_session.get(ProjectTask, task_id)
        if task and task.project_id == project_id:
            db_session.delete(task)
            db_session.commit()
    return redirect(url_for("project_board", project_id=project_id))


@app.route("/projects/<int:project_id>/tasks/<int:task_id>/move", methods=["POST"])
@login_required
def task_move(project_id, task_id):
    data = request.get_json(silent=True) or {}
    new_status = data.get("status")
    new_position = data.get("position", 0)
    if new_status not in TASK_STATUSES:
        return jsonify({"error": "invalid status"}), 400
    with Session(engine) as db_session:
        proj = db_session.get(Project, project_id)
        if not proj: return jsonify({"error": "project not found"}), 404
        membership = db_session.exec(
            select(ProjectMember).where(ProjectMember.project_id == project_id).where(ProjectMember.user_id == session.get("user_id"))
        ).first()
        perms = project_permissions(proj, session.get("user_id"), session.get("role"), membership)
        if not perms["can_edit"]:
            return jsonify({"error": "no permission"}), 403
        task = db_session.get(ProjectTask, task_id)
        if not task or task.project_id != project_id:
            return jsonify({"error": "task not found"}), 404
        old_status = task.status
        siblings = db_session.exec(
            select(ProjectTask)
            .where(ProjectTask.project_id == project_id)
            .where(ProjectTask.status == new_status)
            .where(ProjectTask.id != task_id)
            .order_by(ProjectTask.position, ProjectTask.id)
        ).all()
        siblings.insert(max(0, min(int(new_position), len(siblings))), task)
        for i, t in enumerate(siblings):
            t.position = i
            if t.id == task_id:
                t.status = new_status
                t.updated_at = datetime.now(timezone.utc)
            db_session.add(t)
        db_session.flush()
        if old_status != new_status:
            olds = db_session.exec(
                select(ProjectTask)
                .where(ProjectTask.project_id == project_id)
                .where(ProjectTask.status == old_status)
                .order_by(ProjectTask.position, ProjectTask.id)
            ).all()
            for i, t in enumerate(olds):
                t.position = i
                db_session.add(t)
        db_session.commit()
    return jsonify({"ok": True})


# ══════════════════════════════════════════════════════════════════════
# МАСТЕР-КЛАССЫ
# ══════════════════════════════════════════════════════════════════════

@app.route("/workshops")
def workshops_list():
    user_id = session.get("user_id")
    user_role = session.get("role")
    current_cat = (request.args.get("category") or "").strip()
    current_status = (request.args.get("status") or "").strip()

    with Session(engine) as db_session:
        all_ws = db_session.exec(select(Workshop).order_by(Workshop.created_at.desc())).all()
        visible = []
        for w in all_ws:
            if w.status == "draft" and not (user_role in ("admin", "professor") or w.lead_id == user_id):
                continue
            if w.visibility == "internal" and not user_id:
                continue
            visible.append(w)

        reg_counts = {}
        for w in visible:
            reg_counts[w.id] = _ws_count_registered(db_session, w.id)

        next_sessions = {}
        now = datetime.now(timezone.utc)
        for w in visible:
            sessions = _ws_session_helpers(db_session, w.id)
            future = [s for s in sessions if s.start_time >= now]
            next_sessions[w.id] = future[0] if future else (sessions[-1] if sessions else None)

        lead_ids = {w.lead_id for w in visible}
        leads_map = {}
        if lead_ids:
            for u in db_session.exec(select(User).where(User.id.in_(lead_ids))).all():
                leads_map[u.id] = u

    filtered = visible
    if current_cat:
        filtered = [w for w in filtered if w.category == current_cat]
    if current_status:
        filtered = [w for w in filtered if w.status == current_status]

    can_create = user_role in ("admin", "professor", "lead")

    return render_template("workshops.html",
                           workshops=filtered,
                           reg_counts=reg_counts,
                           next_sessions=next_sessions,
                           leads_map=leads_map,
                           current_cat=current_cat,
                           current_status=current_status,
                           can_create=can_create,
                           WORKSHOP_CATEGORIES=WORKSHOP_CATEGORIES,
                           WORKSHOP_CATEGORY_LABELS=WORKSHOP_CATEGORY_LABELS,
                           WORKSHOP_DIFFICULTY_LABELS=WORKSHOP_DIFFICULTY_LABELS,
                           WORKSHOP_STATUS_LABELS=WORKSHOP_STATUS_LABELS,
                           WORKSHOP_VISIBILITY_LABELS=WORKSHOP_VISIBILITY_LABELS)


@app.route("/workshops/new", methods=["GET", "POST"])
@require_role(["admin", "professor", "lead"])
def workshop_new():
    if request.method == "POST":
        with Session(engine) as db_session:
            ws = Workshop(
                title=request.form.get("title"),
                description=request.form.get("description"),
                program=request.form.get("program"),
                lead_id=session.get("user_id"),
                category=request.form.get("category") or "other",
                difficulty=request.form.get("difficulty") or "beginner",
                partner=(request.form.get("partner") or "").strip() or None,
                status=request.form.get("status") or "draft",
                visibility=request.form.get("visibility") or "public",
                location=(request.form.get("location") or "").strip() or None,
                materials_required=request.form.get("materials_required"),
                outcome=request.form.get("outcome"),
                has_certificate=request.form.get("has_certificate") == "on",
                max_participants=int(request.form.get("max_participants")) if (request.form.get("max_participants") or "").strip().isdigit() else None,
                cover_url=(request.form.get("cover_url") or "").strip() or None,
                tags=normalize_tags(request.form.get("tags")),
            )
            db_session.add(ws)
            db_session.flush()
            ws_id = ws.id
            db_session.commit()
        return redirect(url_for("workshop_detail", workshop_id=ws_id))
    return render_template("workshop_form.html", workshop=None, is_edit=False,
                           WORKSHOP_CATEGORIES=WORKSHOP_CATEGORIES,
                           WORKSHOP_CATEGORY_LABELS=WORKSHOP_CATEGORY_LABELS,
                           WORKSHOP_DIFFICULTIES=WORKSHOP_DIFFICULTIES,
                           WORKSHOP_DIFFICULTY_LABELS=WORKSHOP_DIFFICULTY_LABELS,
                           WORKSHOP_STATUSES=WORKSHOP_STATUSES,
                           WORKSHOP_STATUS_LABELS=WORKSHOP_STATUS_LABELS,
                           WORKSHOP_VISIBILITIES=WORKSHOP_VISIBILITIES,
                           WORKSHOP_VISIBILITY_LABELS=WORKSHOP_VISIBILITY_LABELS)


@app.route("/workshops/<int:workshop_id>")
def workshop_detail(workshop_id):
    user_id = session.get("user_id")
    user_role = session.get("role")
    with Session(engine) as db_session:
        ws = db_session.get(Workshop, workshop_id)
        if not ws: return "Мастер-класс не найден", 404
        perms = workshop_permissions(ws, user_id, user_role)
        if ws.status == "draft" and not perms["can_manage"]:
            return "403: Черновик доступен только ведущему", 403
        if ws.visibility == "internal" and not user_id:
            return redirect(url_for("login"))

        lead = db_session.get(User, ws.lead_id)
        sessions = _ws_session_helpers(db_session, workshop_id)

        registration = _ws_registration(db_session, workshop_id, user_id)
        is_registered = registration is not None and registration.status in ("registered", "attended")
        registered_count = _ws_count_registered(db_session, workshop_id)
        is_full = ws.max_participants is not None and registered_count >= ws.max_participants

        materials = db_session.exec(
            select(WorkshopMaterial).where(WorkshopMaterial.workshop_id == workshop_id)
            .order_by(WorkshopMaterial.created_at.desc())
        ).all()
        visible_materials = []
        for m in materials:
            if m.visible_to == "registered" and not (is_registered or perms["can_manage"]):
                continue
            visible_materials.append(m)

        participants = []
        if perms["can_manage"]:
            regs = db_session.exec(
                select(WorkshopRegistration, User)
                .join(User, WorkshopRegistration.user_id == User.id)
                .where(WorkshopRegistration.workshop_id == workshop_id)
                .order_by(WorkshopRegistration.registered_at)
            ).all()
            participants = regs

        material_files_map = {}
        file_ids = [m.file_id for m in visible_materials if m.file_id]
        if file_ids:
            for f in db_session.exec(select(PortalFile).where(PortalFile.id.in_(file_ids))).all():
                material_files_map[f.id] = f

    return render_template("workshop_detail.html",
                           workshop=ws, lead=lead, sessions=sessions,
                           perms=perms, user_id=user_id, role=user_role,
                           registration=registration, is_registered=is_registered,
                           registered_count=registered_count, is_full=is_full,
                           materials=visible_materials,
                           material_files_map=material_files_map,
                           participants=participants,
                           WORKSHOP_CATEGORY_LABELS=WORKSHOP_CATEGORY_LABELS,
                           WORKSHOP_DIFFICULTY_LABELS=WORKSHOP_DIFFICULTY_LABELS,
                           WORKSHOP_STATUS_LABELS=WORKSHOP_STATUS_LABELS,
                           WORKSHOP_VISIBILITY_LABELS=WORKSHOP_VISIBILITY_LABELS)


@app.route("/workshops/<int:workshop_id>/edit", methods=["GET", "POST"])
@login_required
def workshop_edit(workshop_id):
    with Session(engine) as db_session:
        ws = db_session.get(Workshop, workshop_id)
        if not ws: return "Мастер-класс не найден", 404
        perms = workshop_permissions(ws, session.get("user_id"), session.get("role"))
        if not perms["can_manage"]:
            return "403: Нет прав на редактирование", 403
        if request.method == "POST":
            ws.title = request.form.get("title")
            ws.description = request.form.get("description")
            ws.program = request.form.get("program")
            ws.category = request.form.get("category") or "other"
            ws.difficulty = request.form.get("difficulty") or "beginner"
            ws.partner = (request.form.get("partner") or "").strip() or None
            ws.status = request.form.get("status") or "draft"
            ws.visibility = request.form.get("visibility") or "public"
            ws.location = (request.form.get("location") or "").strip() or None
            ws.materials_required = request.form.get("materials_required")
            ws.outcome = request.form.get("outcome")
            ws.has_certificate = request.form.get("has_certificate") == "on"
            max_p = request.form.get("max_participants")
            ws.max_participants = int(max_p) if (max_p or "").strip().isdigit() else None
            ws.cover_url = (request.form.get("cover_url") or "").strip() or None
            ws.tags = normalize_tags(request.form.get("tags"))
            db_session.add(ws)
            db_session.commit()
            return redirect(url_for("workshop_detail", workshop_id=ws.id))
    return render_template("workshop_form.html", workshop=ws, is_edit=True,
                           WORKSHOP_CATEGORIES=WORKSHOP_CATEGORIES,
                           WORKSHOP_CATEGORY_LABELS=WORKSHOP_CATEGORY_LABELS,
                           WORKSHOP_DIFFICULTIES=WORKSHOP_DIFFICULTIES,
                           WORKSHOP_DIFFICULTY_LABELS=WORKSHOP_DIFFICULTY_LABELS,
                           WORKSHOP_STATUSES=WORKSHOP_STATUSES,
                           WORKSHOP_STATUS_LABELS=WORKSHOP_STATUS_LABELS,
                           WORKSHOP_VISIBILITIES=WORKSHOP_VISIBILITIES,
                           WORKSHOP_VISIBILITY_LABELS=WORKSHOP_VISIBILITY_LABELS)


@app.route("/workshops/<int:workshop_id>/delete", methods=["POST"])
@login_required
def workshop_delete(workshop_id):
    with Session(engine) as db_session:
        ws = db_session.get(Workshop, workshop_id)
        if not ws: return redirect(url_for("workshops_list"))
        perms = workshop_permissions(ws, session.get("user_id"), session.get("role"))
        if not perms["can_delete"]:
            return "403: Удалять мастер-класс может только ведущий или админ", 403
        db_session.delete(ws)
        db_session.commit()
    return redirect(url_for("workshops_list"))


@app.route("/workshops/<int:workshop_id>/sessions/add", methods=["POST"])
@login_required
def workshop_session_add(workshop_id):
    with Session(engine) as db_session:
        ws = db_session.get(Workshop, workshop_id)
        if not ws: return "Мастер-класс не найден", 404
        perms = workshop_permissions(ws, session.get("user_id"), session.get("role"))
        if not perms["can_manage"]: return "403: Нет прав", 403
        start = parse_datetime(request.form.get("start_time"))
        end = parse_datetime(request.form.get("end_time"))
        if start and end:
            db_session.add(WorkshopSession(
                workshop_id=workshop_id,
                start_time=start, end_time=end,
                location_override=(request.form.get("location_override") or "").strip() or None,
                note=(request.form.get("note") or "").strip() or None,
            ))
            db_session.commit()
    return redirect(url_for("workshop_detail", workshop_id=workshop_id))


@app.route("/workshops/<int:workshop_id>/sessions/<int:session_id>/delete", methods=["POST"])
@login_required
def workshop_session_delete(workshop_id, session_id):
    with Session(engine) as db_session:
        ws = db_session.get(Workshop, workshop_id)
        if not ws: return redirect(url_for("workshops_list"))
        perms = workshop_permissions(ws, session.get("user_id"), session.get("role"))
        if not perms["can_manage"]: return "403: Нет прав", 403
        s = db_session.get(WorkshopSession, session_id)
        if s and s.workshop_id == workshop_id:
            db_session.delete(s)
            db_session.commit()
    return redirect(url_for("workshop_detail", workshop_id=workshop_id))


@app.route("/workshops/<int:workshop_id>/materials/add", methods=["POST"])
@login_required
def workshop_material_add(workshop_id):
    with Session(engine) as db_session:
        ws = db_session.get(Workshop, workshop_id)
        if not ws: return "Мастер-класс не найден", 404
        perms = workshop_permissions(ws, session.get("user_id"), session.get("role"))
        if not perms["can_manage"]: return "403: Нет прав", 403
        title = (request.form.get("title") or "").strip()
        if title:
            db_session.add(WorkshopMaterial(
                workshop_id=workshop_id, title=title,
                description=(request.form.get("description") or "").strip() or None,
                external_url=(request.form.get("external_url") or "").strip() or None,
                visible_to=request.form.get("visible_to") or "registered",
            ))
            db_session.commit()
            regs = db_session.exec(
                select(WorkshopRegistration).where(WorkshopRegistration.workshop_id == workshop_id)
                .where(WorkshopRegistration.status.in_(("registered", "attended")))
            ).all()
            recipients = [r.user_id for r in regs if r.user_id != session.get("user_id")]
            if recipients:
                notify_users(recipients,
                             f"Новый материал в «{ws.title}»",
                             title,
                             link_url=url_for("workshop_detail", workshop_id=workshop_id),
                             kind="info")
    return redirect(url_for("workshop_detail", workshop_id=workshop_id))


@app.route("/workshops/<int:workshop_id>/materials/<int:material_id>/delete", methods=["POST"])
@login_required
def workshop_material_delete(workshop_id, material_id):
    with Session(engine) as db_session:
        ws = db_session.get(Workshop, workshop_id)
        if not ws: return redirect(url_for("workshops_list"))
        perms = workshop_permissions(ws, session.get("user_id"), session.get("role"))
        if not perms["can_manage"]: return "403: Нет прав", 403
        m = db_session.get(WorkshopMaterial, material_id)
        if m and m.workshop_id == workshop_id:
            db_session.delete(m)
            db_session.commit()
    return redirect(url_for("workshop_detail", workshop_id=workshop_id))


@app.route("/workshops/<int:workshop_id>/register", methods=["POST"])
@login_required
def workshop_register(workshop_id):
    with Session(engine) as db_session:
        ws = db_session.get(Workshop, workshop_id)
        if not ws: return "Мастер-класс не найден", 404
        if ws.status != "published":
            return "Регистрация доступна только для опубликованных", 400
        existing = _ws_registration(db_session, workshop_id, session.get("user_id"))
        if existing and existing.status in ("registered", "attended"):
            return redirect(url_for("workshop_detail", workshop_id=workshop_id))
        if ws.max_participants is not None:
            count = _ws_count_registered(db_session, workshop_id)
            if count >= ws.max_participants:
                return redirect(url_for("workshop_detail", workshop_id=workshop_id))
        if existing:
            existing.status = "registered"
            existing.registered_at = datetime.now(timezone.utc)
            db_session.add(existing)
        else:
            db_session.add(WorkshopRegistration(
                workshop_id=workshop_id, user_id=session.get("user_id"),
                status="registered",
            ))
        db_session.commit()
        if ws.lead_id != session.get("user_id"):
            notify_user(ws.lead_id,
                        f"Новая запись на «{ws.title}»",
                        f"Пользователь записался на ваш мастер-класс.",
                        link_url=url_for("workshop_detail", workshop_id=workshop_id),
                        kind="success")
    return redirect(url_for("workshop_detail", workshop_id=workshop_id))


@app.route("/workshops/<int:workshop_id>/unregister", methods=["POST"])
@login_required
def workshop_unregister(workshop_id):
    with Session(engine) as db_session:
        ws = db_session.get(Workshop, workshop_id)
        existing = _ws_registration(db_session, workshop_id, session.get("user_id"))
        if existing:
            existing.status = "cancelled"
            db_session.add(existing)
            db_session.commit()
            if ws and ws.lead_id != session.get("user_id"):
                notify_user(ws.lead_id,
                            f"Отмена записи на «{ws.title}»",
                            "Пользователь отменил запись на ваш мастер-класс.",
                            link_url=url_for("workshop_detail", workshop_id=workshop_id),
                            kind="warning")
    return redirect(url_for("workshop_detail", workshop_id=workshop_id))


# ══════════════════════════════════════════════════════════════════════
# ФАЙЛЫ
# ══════════════════════════════════════════════════════════════════════

@app.route("/files")
@login_required
def files_list():
    with Session(engine) as db_session:
        files = db_session.exec(
            select(PortalFile, User.username).join(User, PortalFile.uploaded_by == User.id)
            .order_by(PortalFile.uploaded_at.desc())
        ).all()
        projects_map = {p.id: p.title for p in db_session.exec(select(Project)).all()}
    return render_template("files.html", files=files, projects_map=projects_map)


@app.route("/files/upload", methods=["POST"])
@login_required
def file_upload():
    try:
        file = request.files.get('file')
    except Exception as e:
        print(f"[file_upload] Ошибка парсинга: {e}", flush=True)
        return "Ошибка разбора запроса", 400
    if not file or file.filename == '':
        return redirect(url_for('files_list'))
    original_name = file.filename
    ext = os.path.splitext(original_name)[1]
    stored_name = f"{uuid.uuid4().hex}{ext}"
    filepath = os.path.join(app.config['UPLOAD_FOLDER'], stored_name)
    try:
        file.save(filepath)
        size_bytes = os.path.getsize(filepath)
    except Exception as e:
        print(f"[file_upload] Ошибка сохранения: {e}", flush=True)
        return "Ошибка сохранения файла", 500
    try:
        with Session(engine) as db_session:
            db_session.add(PortalFile(
                original_name=original_name, stored_name=stored_name,
                size_bytes=size_bytes, uploaded_by=session.get("user_id"),
            ))
            db_session.commit()
    except Exception as e:
        print(f"[file_upload] Ошибка БД: {e}", flush=True)
        try: os.remove(filepath)
        except Exception: pass
        return "Ошибка записи в БД", 500
    return redirect(url_for('files_list'))


@app.route("/files/download/<int:file_id>")
@login_required
def file_download(file_id):
    with Session(engine) as db_session:
        db_file = db_session.get(PortalFile, file_id)
        if db_file:
            return send_from_directory(app.config['UPLOAD_FOLDER'], db_file.stored_name, as_attachment=True, download_name=db_file.original_name)
    return "Файл не найден", 404


@app.route("/files/<int:file_id>/delete", methods=["POST"])
@login_required
def file_delete(file_id):
    next_url = request.form.get("next") or "/files"
    if not next_url.startswith("/"): next_url = "/files"
    with Session(engine) as db_session:
        db_file = db_session.get(PortalFile, file_id)
        if not db_file: return redirect(next_url)
        allowed = session.get("role") == "admin" or db_file.uploaded_by == session.get("user_id")
        if not allowed and db_file.project_id:
            proj = db_session.get(Project, db_file.project_id)
            if proj:
                membership = db_session.exec(
                    select(ProjectMember).where(ProjectMember.project_id == db_file.project_id).where(ProjectMember.user_id == session.get("user_id"))
                ).first()
                perms = project_permissions(proj, session.get("user_id"), session.get("role"), membership)
                if perms["can_manage"]: allowed = True
        if allowed:
            filepath = os.path.join(app.config['UPLOAD_FOLDER'], db_file.stored_name)
            if os.path.exists(filepath): os.remove(filepath)
            db_session.delete(db_file)
            db_session.commit()
    return redirect(next_url)


# ══════════════════════════════════════════════════════════════════════
# АДМИНКА: ПОЛЬЗОВАТЕЛИ
# ══════════════════════════════════════════════════════════════════════

@app.route("/admin/users")
@require_role("admin")
def admin_users():
    with Session(engine) as db_session:
        users = db_session.exec(select(User).order_by(User.username)).all()
    return render_template("admin_users.html", users=users)


@app.route("/admin/users/<int:user_id>/role", methods=["POST"])
@require_role("admin")
def change_user_role(user_id):
    new_role = request.form.get("role")
    valid_roles = ["admin", "professor", "lead", "member", "student", "guest"]
    if new_role not in valid_roles: return "Ошибка", 400
    with Session(engine) as db_session:
        user = db_session.get(User, user_id)
        if user:
            if user.id == session.get("user_id") and new_role != "admin":
                return "Нельзя снять с себя админа", 400
            user.role = new_role
            db_session.add(user)
            db_session.commit()
    return redirect(url_for("admin_users"))


@app.route("/admin/users/<int:user_id>/delete", methods=["POST"])
@require_role("admin")
def delete_user(user_id):
    if user_id == session.get("user_id"): return "Нельзя удалить себя", 400
    with Session(engine) as db_session:
        user = db_session.get(User, user_id)
        if not user:
            return redirect(url_for("admin_users"))
        owned_projects = db_session.exec(select(Project).where(Project.owner_id == user_id)).all()
        uploaded_files = db_session.exec(select(PortalFile).where(PortalFile.uploaded_by == user_id)).all()
        if owned_projects or uploaded_files:
            return (f"Нельзя удалить {user.username}: у него {len(owned_projects)} проект(ов) "
                    f"и {len(uploaded_files)} файл(ов)."), 400
        owned_workshops = db_session.exec(select(Workshop).where(Workshop.lead_id == user_id)).all()
        if owned_workshops:
            return (f"Нельзя удалить {user.username}: он ведёт {len(owned_workshops)} мастер-класс(ов)."), 400
        for pm in db_session.exec(select(ProjectMember).where(ProjectMember.user_id == user_id)).all():
            db_session.delete(pm)
        for s in db_session.exec(select(UserSession).where(UserSession.user_id == user_id)).all():
            db_session.delete(s)
        for sub in db_session.exec(select(EventSubscriber).where(EventSubscriber.user_id == user_id)).all():
            sub.user_id = None
            db_session.add(sub)
        for t in db_session.exec(select(ProjectTask).where(ProjectTask.assignee_id == user_id)).all():
            t.assignee_id = None
            db_session.add(t)
        for n in db_session.exec(select(Notification).where(Notification.user_id == user_id)).all():
            db_session.delete(n)
        db_session.delete(user)
        db_session.commit()
    return redirect(url_for("admin_users"))