use defuse_ton_connect::{SignedTonConnectPayload, TonConnectPayload, TonConnectPayloadSchema};
use near_sdk::{
    serde::de::{DeserializeOwned, Error},
    serde_json,
};

use super::{DefusePayload, ExtractDefusePayload};

impl<T> ExtractDefusePayload<T> for SignedTonConnectPayload
where
    T: DeserializeOwned,
{
    type Error = serde_json::Error;

    #[inline]
    fn extract_defuse_payload(self) -> Result<DefusePayload<T>, Self::Error> {
        self.payload.extract_defuse_payload()
    }
}

impl<T> ExtractDefusePayload<T> for TonConnectPayload
where
    T: DeserializeOwned,
{
    type Error = serde_json::Error;

    fn extract_defuse_payload(self) -> Result<DefusePayload<T>, Self::Error> {
        #[allow(irrefutable_let_patterns)]
        let TonConnectPayloadSchema::Text(text) = self.payload else {
            return Err(Error::custom("only text payload supported"));
        };

        let p: DefusePayload<T> = serde_json::from_str(&text)?;

        // TON Connect [specification](https://docs.tonconsole.com/academy/sign-data#in-a-smart-contract-on-chain)
        // requires to check that "timestamp is recent". We don't have fixed TTL
        // for off-chain signatures but rather check if `deadline` is not expired.
        //
        // At first, we were asserting `(timestamp <= now())`, but that  was causing
        // `simulate_intents()` to fail, since sometimes signed intent is simulated
        // right after signing.
        //
        // So, we ended up to assert at least following:
        if p.deadline.into_timestamp() < self.timestamp {
            return Err(Error::custom("deadline < timestamp"));
        }

        Ok(p)
    }
}