from datetime import datetime, timezone

from fastapi import HTTPException, status
from sqlalchemy.orm import Session

from ..accounts.models import Account
from .dto import ContactCreate, ContactUpdate
from .models import Contact


def _validate_account(db: Session, account_id: int | None, tenant_id: int, company_id: int) -> None:
    """Verifica que la cuenta referenciada exista dentro del tenant/company."""
    if account_id is None:
        return
    exists = (
        db.query(Account.id)
        .filter(
            Account.id == account_id,
            Account.tenant_id == tenant_id,
            Account.company_id == company_id,
            Account.deleted_at.is_(None),
        )
        .first()
    )
    if not exists:
        raise HTTPException(
            status_code=status.HTTP_422_UNPROCESSABLE_ENTITY,
            detail="La cuenta asociada no existe",
        )


def get_contacts(
    db: Session,
    tenant_id: int,
    company_id: int,
    search: str | None = None,
    account_id: int | None = None,
) -> list[Contact]:
    query = db.query(Contact).filter(
        Contact.tenant_id == tenant_id,
        Contact.company_id == company_id,
        Contact.deleted_at.is_(None),
    )
    if account_id is not None:
        query = query.filter(Contact.account_id == account_id)
    if search:
        pattern = f"%{search}%"
        query = query.filter(
            Contact.first_name.ilike(pattern)
            | Contact.last_name.ilike(pattern)
            | Contact.email.ilike(pattern)
        )
    return query.order_by(Contact.first_name.asc()).all()


def get_contact(db: Session, contact_id: int, tenant_id: int, company_id: int) -> Contact:
    contact = (
        db.query(Contact)
        .filter(
            Contact.id == contact_id,
            Contact.tenant_id == tenant_id,
            Contact.company_id == company_id,
            Contact.deleted_at.is_(None),
        )
        .first()
    )
    if not contact:
        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail="Contacto no encontrado")
    return contact


def create_contact(db: Session, payload: ContactCreate, tenant_id: int, company_id: int) -> Contact:
    _validate_account(db, payload.account_id, tenant_id, company_id)
    contact = Contact(**payload.model_dump(), tenant_id=tenant_id, company_id=company_id)
    db.add(contact)
    db.commit()
    db.refresh(contact)
    return contact


def update_contact(
    db: Session, contact_id: int, payload: ContactUpdate, tenant_id: int, company_id: int
) -> Contact:
    contact = get_contact(db, contact_id, tenant_id, company_id)
    data = payload.model_dump(exclude_unset=True)
    if "account_id" in data:
        _validate_account(db, data["account_id"], tenant_id, company_id)
    for field, value in data.items():
        setattr(contact, field, value)
    db.commit()
    db.refresh(contact)
    return contact


def delete_contact(db: Session, contact_id: int, tenant_id: int, company_id: int) -> None:
    contact = get_contact(db, contact_id, tenant_id, company_id)
    contact.deleted_at = datetime.now(timezone.utc)
    db.commit()