from fastapi import APIRouter, Depends
from sqlalchemy.orm import Session
from app.core.db import get_db
from app.core.deps import get_current_user
from app.models import Permission, RolePermission, UserRole, User
from app.models.enums import StatusEnum, PermissionTypeEnum

router = APIRouter(prefix="/menus", tags=["menus"])


def build_tree(items):
    by_parent = {}
    for item in items:
        by_parent.setdefault(item.parent_id, []).append(item)

    def make_node(item):
        return {
            "id": item.perm_id,
            "name": item.name,
            "code": item.code,
            "type": item.perm_type,
            "level": item.level,
            "path": item.path,
            "icon": item.icon,
            "children": [make_node(child) for child in by_parent.get(item.perm_id, [])],
        }

    roots = by_parent.get(None, []) + by_parent.get(0, [])
    return [make_node(node) for node in roots]


@router.get("/tree")
def menu_tree(
    db: Session = Depends(get_db),
    current_user: User = Depends(get_current_user),
):
    items = (
        db.query(Permission)
        .join(RolePermission, RolePermission.perm_id == Permission.perm_id)
        .join(UserRole, UserRole.role_id == RolePermission.role_id)
        .filter(UserRole.user_id == current_user.user_id)
        .filter(Permission.status == int(StatusEnum.ENABLED))
        .filter(Permission.perm_type.in_([PermissionTypeEnum.MENU, PermissionTypeEnum.BUTTON]))
        .order_by(Permission.level, Permission.sort_order)
        .all()
    )
    return build_tree(items)