"""
Audit Log Events
"""

from sqlalchemy import event, inspect
from sqlalchemy.orm import Session
from .services.service import AuditService
from .utils.serialization import serialize_for_json
from core.context import get_user_context


def register_audit_listeners(models_to_audit):
    """
    Register SQLAlchemy listeners for given models
    """
    for model in models_to_audit:
        event.listen(model, "after_insert", after_insert_listener)
        event.listen(model, "after_update", after_update_listener)
        event.listen(model, "after_delete", after_delete_listener)


def _get_current_username():
    try:
        context = get_user_context()
        if context:
            # Token usually has 'preferred_username' or 'name' or 'sub'
            return (
                context.get("preferred_username")
                or context.get("email")
                or context.get("sub")
                or "System"
            )
    except:
        pass
    return "System"


def after_insert_listener(mapper, connection, target):
    """
    Listener for INSERT operations
    """
    table_name = target.__tablename__
    record_data = {c.name: getattr(target, c.name) for c in mapper.columns}
    username = _get_current_username()
    company_id = getattr(target, "company_id", None) or getattr(target, "id", None)
    tenant_id = getattr(target, "tenant_id", None)

    # Create a session bound to the connection
    session = Session(bind=connection)
    try:
        AuditService.log_crud_operation(
            db=session,
            table_name=table_name,
            operation_type="CREATE",
            record_data=record_data,
            username=username,
            record_id=str(getattr(target, "id", "")),
            company_id=company_id,
            tenant_id=tenant_id,
        )
    except Exception as e:
        print(f"Error logging insert: {e}")
    finally:
        session.close()


def after_update_listener(mapper, connection, target):
    """
    Listener for UPDATE operations
    """
    table_name = target.__tablename__

    state = inspect(target)
    changes = {}
    old_values = {}
    new_values = {}

    for attr in state.attrs:
        hist = attr.history
        if hist.has_changes():
            changes[attr.key] = hist.added[0] if hist.added else None
            old_values[attr.key] = hist.deleted[0] if hist.deleted else None
            new_values[attr.key] = hist.added[0] if hist.added else None

    if not changes:
        return

    record_data = {c.name: getattr(target, c.name) for c in mapper.columns}
    username = _get_current_username()
    company_id = getattr(target, "company_id", None) or getattr(target, "id", None)
    tenant_id = getattr(target, "tenant_id", None)

    session = Session(bind=connection)
    try:
        AuditService.log_crud_operation(
            db=session,
            table_name=table_name,
            operation_type="UPDATE",
            record_data=record_data,
            username=username,
            record_id=str(getattr(target, "id", "")),
            old_values=serialize_for_json(old_values),
            new_values=serialize_for_json(new_values),
            company_id=company_id,
            tenant_id=tenant_id,
        )
    except Exception as e:
        print(f"Error logging update: {e}")
    finally:
        session.close()


def after_delete_listener(mapper, connection, target):
    """
    Listener for DELETE operations
    """
    table_name = target.__tablename__
    record_data = {c.name: getattr(target, c.name) for c in mapper.columns}
    username = _get_current_username()
    company_id = getattr(target, "company_id", None) or getattr(target, "id", None)
    tenant_id = getattr(target, "tenant_id", None)

    session = Session(bind=connection)
    try:
        AuditService.log_crud_operation(
            db=session,
            table_name=table_name,
            operation_type="DELETE",
            record_data=record_data,
            username=username,
            record_id=str(getattr(target, "id", "")),
            company_id=company_id,
            tenant_id=tenant_id,
        )
    except Exception as e:
        print(f"Error logging delete: {e}")
    finally:
        session.close()