#[smart_beaver::extension]
pub mod ownable_extension {
    use crate::traits::Ownable;
    use crate::errors::OwnableError;

    #[smart_beaver::storage]
    pub struct Token {
        #[smart_beaver::init(Some(Self::env().caller()))]
        pub owner: Option<AccountId>,
    }

    impl Ownable for Token {
        #[ink(message)]
        fn owner(&self) -> Option<AccountId> {
            self.owner
        }

        #[ink(message)]
        fn renounce_ownership(&mut self) -> Result<(), OwnableError> {
            assert_eq!(Some(self.env().caller()), self.owner, "Only owner can renounce ownership");
            self.owner = None;
            Ok(())
        }

        #[ink(message)]
        fn transfer_ownership(&mut self, new_owner: Option<AccountId>) -> Result<(), OwnableError> {
            assert_eq!(Some(self.env().caller()), self.owner, "Only owner can transfer ownership");
            self.owner = new_owner;
            Ok(())
        }
    }
}