from sqlalchemy import or_
from sqlalchemy.orm import Query, Session

from app.models.document import FilledDocument
from app.models.template import DocumentTemplate
from app.models.user import User, UserRole


def is_admin(user: User) -> bool:
    return user.role == UserRole.admin


def can_access_template(user: User, template: DocumentTemplate) -> bool:
    return (
        is_admin(user)
        or template.owner_id == user.id
        or template.is_public
    )


def can_manage_template(user: User, template: DocumentTemplate) -> bool:
    return is_admin(user) or template.owner_id == user.id


def can_access_document(user: User, document: FilledDocument) -> bool:
    return is_admin(user) or document.owner_id == user.id


def accessible_templates_query(db: Session, user: User) -> Query:
    return db.query(DocumentTemplate).filter(
        or_(
            DocumentTemplate.owner_id == user.id,
            DocumentTemplate.is_public == True,
        )
    )


def accessible_template(
    db: Session, user: User, template_id: int
) -> DocumentTemplate | None:
    template = db.query(DocumentTemplate).filter(
        DocumentTemplate.id == template_id
    ).first()
    if template and can_access_template(user, template):
        return template
    return None


def manageable_template(
    db: Session, user: User, template_id: int
) -> DocumentTemplate | None:
    template = db.query(DocumentTemplate).filter(
        DocumentTemplate.id == template_id
    ).first()
    if template and can_manage_template(user, template):
        return template
    return None


def accessible_document(
    db: Session, user: User, document_id: int
) -> FilledDocument | None:
    doc = db.query(FilledDocument).filter(FilledDocument.id == document_id).first()
    if doc and can_access_document(user, doc):
        return doc
    return None