"""Disclosure request service — create, review, check active grants."""

from datetime import datetime, timedelta, timezone
from typing import Optional

from sqlalchemy.orm import Session

from app.models.audit import DisclosureRequest, Notification
from app.models.case import Case
from app.models.user import User


def has_active_disclosure(db: Session, case_id: int, user_id: int) -> tuple[bool, Optional[datetime]]:
    """Check if user has an active (approved, non-expired) disclosure for a case.

    Returns (granted: bool, expires_at: datetime | None).
    """
    dr = (
        db.query(DisclosureRequest)
        .filter(
            DisclosureRequest.case_id == case_id,
            DisclosureRequest.requester_id == user_id,
            DisclosureRequest.status == "approved",
            DisclosureRequest.expires_at > datetime.now(timezone.utc),
        )
        .first()
    )
    if dr:
        return True, dr.expires_at
    return False, None


def has_pending_request(db: Session, case_id: int, user_id: int) -> bool:
    """Check if user already has a pending disclosure request for a case."""
    return (
        db.query(DisclosureRequest)
        .filter(
            DisclosureRequest.case_id == case_id,
            DisclosureRequest.requester_id == user_id,
            DisclosureRequest.status == "pending",
        )
        .first()
    ) is not None


def create_disclosure_request(
    db: Session, case_id: int, user_id: int, reason: str
) -> DisclosureRequest:
    """Create a new disclosure request and notify admins."""
    dr = DisclosureRequest(
        case_id=case_id,
        requester_id=user_id,
        reason=reason,
    )
    db.add(dr)
    db.flush()

    # Notify all active admins
    case = db.query(Case).filter(Case.id == case_id).first()
    fall_id = case.fall_id if case else str(case_id)
    requester = db.query(User).filter(User.id == user_id).first()
    requester_name = requester.username if requester else str(user_id)

    admins = db.query(User).filter(User.role == "admin", User.is_active == True).all()  # noqa: E712
    for admin in admins:
        db.add(Notification(
            recipient_id=admin.id,
            notification_type="disclosure_request",
            title=f"Freigabe-Anfrage für Fall {fall_id}",
            message=f"{requester_name} bittet um Einsicht in Personendaten. Begründung: {reason}",
            related_entity_type="disclosure_request",
            related_entity_id=dr.id,
        ))

    db.commit()
    db.refresh(dr)
    return dr


def review_disclosure_request(
    db: Session, request_id: int, admin_id: int, new_status: str
) -> DisclosureRequest:
    """Approve or reject a disclosure request."""
    dr = db.query(DisclosureRequest).filter(DisclosureRequest.id == request_id).first()
    if not dr:
        raise ValueError("Disclosure request not found")
    if dr.status != "pending":
        raise ValueError("Request already reviewed")

    dr.status = new_status
    dr.reviewed_by = admin_id
    dr.reviewed_at = datetime.now(timezone.utc)

    if new_status == "approved":
        dr.expires_at = datetime.now(timezone.utc) + timedelta(hours=24)

    # Notify requester
    case = db.query(Case).filter(Case.id == dr.case_id).first()
    fall_id = case.fall_id if case else str(dr.case_id)

    status_text = "genehmigt" if new_status == "approved" else "abgelehnt"
    db.add(Notification(
        recipient_id=dr.requester_id,
        notification_type="disclosure_resolved",
        title=f"Freigabe-Anfrage {status_text}",
        message=f"Ihre Anfrage für Fall {fall_id} wurde {status_text}.",
        related_entity_type="disclosure_request",
        related_entity_id=dr.id,
    ))

    db.commit()
    db.refresh(dr)
    return dr


def get_pending_requests(db: Session) -> list[DisclosureRequest]:
    """Return all pending disclosure requests."""
    return (
        db.query(DisclosureRequest)
        .filter(DisclosureRequest.status == "pending")
        .order_by(DisclosureRequest.created_at.desc())
        .all()
    )


def get_pending_count(db: Session) -> int:
    """Return count of pending disclosure requests."""
    return (
        db.query(DisclosureRequest)
        .filter(DisclosureRequest.status == "pending")
        .count()
    )