cdk/crates/cashu/src/nuts/nut00/token.rs

//! Cashu Token
//!
//! <https://github.com/cashubtc/nuts/blob/main/00.md>

use std::collections::HashMap;
use std::fmt;
use std::str::FromStr;

use bitcoin::base64::engine::{general_purpose, GeneralPurpose};
use bitcoin::base64::{alphabet, Engine as _};
use serde::{Deserialize, Serialize};

use super::{Error, Proof, ProofV3, ProofV4, Proofs};
use crate::mint_url::MintUrl;
use crate::nut02::ShortKeysetId;
use crate::nuts::{CurrencyUnit, Id};
use crate::{ensure_cdk, Amount, KeySetInfo};

/// Token Enum
#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
#[serde(untagged)]
pub enum Token {
    /// Token V3
    TokenV3(TokenV3),
    /// Token V4
    TokenV4(TokenV4),
}

impl fmt::Display for Token {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        let token = match self {
            Self::TokenV3(token) => token.to_string(),
            Self::TokenV4(token) => token.to_string(),
        };

        write!(f, "{token}")
    }
}

impl Token {
    /// Create new [`Token`]
    pub fn new(
        mint_url: MintUrl,
        proofs: Proofs,
        memo: Option<String>,
        unit: CurrencyUnit,
    ) -> Self {
        let proofs = proofs
            .into_iter()
            .fold(HashMap::new(), |mut acc, val| {
                acc.entry(val.keyset_id)
                    .and_modify(|p: &mut Vec<Proof>| p.push(val.clone()))
                    .or_insert(vec![val.clone()]);
                acc
            })
            .into_iter()
            .map(|(id, proofs)| TokenV4Token::new(id, proofs))
            .collect();

        Token::TokenV4(TokenV4 {
            mint_url,
            unit,
            memo,
            token: proofs,
        })
    }

    /// Proofs in [`Token`]
    pub fn proofs(&self, mint_keysets: &[KeySetInfo]) -> Result<Proofs, Error> {
        match self {
            Self::TokenV3(token) => token.proofs(mint_keysets),
            Self::TokenV4(token) => token.proofs(mint_keysets),
        }
    }

    /// Total value of [`Token`]
    pub fn value(&self) -> Result<Amount, Error> {
        match self {
            Self::TokenV3(token) => token.value(),
            Self::TokenV4(token) => token.value(),
        }
    }

    /// [`Token`] memo
    pub fn memo(&self) -> &Option<String> {
        match self {
            Self::TokenV3(token) => token.memo(),
            Self::TokenV4(token) => token.memo(),
        }
    }

    /// Unit
    pub fn unit(&self) -> Option<CurrencyUnit> {
        match self {
            Self::TokenV3(token) => token.unit().clone(),
            Self::TokenV4(token) => Some(token.unit().clone()),
        }
    }

    /// Mint url
    pub fn mint_url(&self) -> Result<MintUrl, Error> {
        match self {
            Self::TokenV3(token) => {
                let mint_urls = token.mint_urls();

                ensure_cdk!(mint_urls.len() == 1, Error::UnsupportedToken);

                mint_urls.first().ok_or(Error::UnsupportedToken).cloned()
            }
            Self::TokenV4(token) => Ok(token.mint_url.clone()),
        }
    }

    /// To v3 string
    pub fn to_v3_string(&self) -> String {
        let v3_token = match self {
            Self::TokenV3(token) => token.clone(),
            Self::TokenV4(token) => token.clone().into(),
        };

        v3_token.to_string()
    }

    /// Serialize the token to raw binary
    pub fn to_raw_bytes(&self) -> Result<Vec<u8>, Error> {
        match self {
            Self::TokenV3(_) => Err(Error::UnsupportedToken),
            Self::TokenV4(token) => token.to_raw_bytes(),
        }
    }
}

impl FromStr for Token {
    type Err = Error;

    fn from_str(s: &str) -> Result<Self, Self::Err> {
        let (is_v3, s) = match (s.strip_prefix("cashuA"), s.strip_prefix("cashuB")) {
            (Some(s), None) => (true, s),
            (None, Some(s)) => (false, s),
            _ => return Err(Error::UnsupportedToken),
        };

        let decode_config = general_purpose::GeneralPurposeConfig::new()
            .with_decode_padding_mode(bitcoin::base64::engine::DecodePaddingMode::Indifferent);
        let decoded = GeneralPurpose::new(&alphabet::URL_SAFE, decode_config).decode(s)?;

        match is_v3 {
            true => {
                let decoded_str = String::from_utf8(decoded)?;
                let token: TokenV3 = serde_json::from_str(&decoded_str)?;
                Ok(Token::TokenV3(token))
            }
            false => {
                let token: TokenV4 = ciborium::from_reader(&decoded[..])?;
                Ok(Token::TokenV4(token))
            }
        }
    }
}

impl TryFrom<&Vec<u8>> for Token {
    type Error = Error;

    fn try_from(bytes: &Vec<u8>) -> Result<Self, Self::Error> {
        ensure_cdk!(bytes.len() >= 5, Error::UnsupportedToken);

        let prefix = String::from_utf8(bytes[..5].to_vec())?;

        match prefix.as_str() {
            "crawB" => {
                let token: TokenV4 = ciborium::from_reader(&bytes[5..])?;
                Ok(Token::TokenV4(token))
            }
            _ => Err(Error::UnsupportedToken),
        }
    }
}

/// Token V3 Token
#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
pub struct TokenV3Token {
    /// Url of mint
    pub mint: MintUrl,
    /// [`Vec<ProofV3>`]
    pub proofs: Vec<ProofV3>,
}

impl TokenV3Token {
    /// Create new [`TokenV3Token`]
    pub fn new(mint_url: MintUrl, proofs: Proofs) -> Self {
        Self {
            mint: mint_url,
            proofs: proofs.into_iter().map(ProofV3::from).collect(),
        }
    }
}

/// Token
#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
pub struct TokenV3 {
    /// Proofs in [`Token`] by mint
    pub token: Vec<TokenV3Token>,
    /// Memo for token
    #[serde(skip_serializing_if = "Option::is_none")]
    pub memo: Option<String>,
    /// Token Unit
    #[serde(skip_serializing_if = "Option::is_none")]
    pub unit: Option<CurrencyUnit>,
}

impl TokenV3 {
    /// Create new [`Token`]
    pub fn new(
        mint_url: MintUrl,
        proofs: Proofs,
        memo: Option<String>,
        unit: Option<CurrencyUnit>,
    ) -> Result<Self, Error> {
        ensure_cdk!(!proofs.is_empty(), Error::ProofsRequired);

        Ok(Self {
            token: vec![TokenV3Token::new(mint_url, proofs)],
            memo,
            unit,
        })
    }

    /// Proofs
    pub fn proofs(&self, mint_keysets: &[KeySetInfo]) -> Result<Proofs, Error> {
        let mut proofs: Proofs = vec![];
        for t in self.token.iter() {
            for p in t.proofs.iter() {
                let long_id = Id::from_short_keyset_id(&p.keyset_id, mint_keysets)?;
                proofs.push(p.into_proof(&long_id));
            }
        }
        Ok(proofs)
    }

    /// Value - errors if duplicate proofs are found
    #[inline]
    pub fn value(&self) -> Result<Amount, Error> {
        let proofs: Vec<ProofV3> = self.token.iter().flat_map(|t| t.proofs.clone()).collect();
        let unique_count = proofs
            .iter()
            .collect::<std::collections::HashSet<_>>()
            .len();

        // Check if there are any duplicate proofs
        if unique_count != proofs.len() {
            return Err(Error::DuplicateProofs);
        }

        Ok(Amount::try_sum(
            self.token
                .iter()
                .map(|t| Amount::try_sum(t.proofs.iter().map(|p| p.amount)))
                .collect::<Result<Vec<Amount>, _>>()?,
        )?)
    }

    /// Memo
    #[inline]
    pub fn memo(&self) -> &Option<String> {
        &self.memo
    }

    /// Unit
    #[inline]
    pub fn unit(&self) -> &Option<CurrencyUnit> {
        &self.unit
    }

    /// Mint Url
    pub fn mint_urls(&self) -> Vec<MintUrl> {
        let mut mint_urls = Vec::new();

        for token in self.token.iter() {
            mint_urls.push(token.mint.clone());
        }

        mint_urls
    }

    /// Checks if a token has multiple mints
    ///
    /// These tokens are not supported by this crate
    pub fn is_multi_mint(&self) -> bool {
        self.token.len() > 1
    }
}

impl FromStr for TokenV3 {
    type Err = Error;

    fn from_str(s: &str) -> Result<Self, Self::Err> {
        let s = s.strip_prefix("cashuA").ok_or(Error::UnsupportedToken)?;

        let decode_config = general_purpose::GeneralPurposeConfig::new()
            .with_decode_padding_mode(bitcoin::base64::engine::DecodePaddingMode::Indifferent);
        let decoded = GeneralPurpose::new(&alphabet::URL_SAFE, decode_config).decode(s)?;
        let decoded_str = String::from_utf8(decoded)?;
        let token: TokenV3 = serde_json::from_str(&decoded_str)?;
        Ok(token)
    }
}

impl fmt::Display for TokenV3 {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        let json_string = serde_json::to_string(self).map_err(|_| fmt::Error)?;
        let encoded = general_purpose::URL_SAFE.encode(json_string);
        write!(f, "cashuA{encoded}")
    }
}

impl From<TokenV4> for TokenV3 {
    fn from(token: TokenV4) -> Self {
        let proofs: Vec<ProofV3> = token
            .token
            .into_iter()
            .flat_map(|token| {
                token.proofs.into_iter().map(move |p| ProofV3 {
                    amount: p.amount,
                    keyset_id: token.keyset_id.clone(),
                    secret: p.secret,
                    c: p.c,
                    witness: p.witness,
                    dleq: p.dleq,
                })
            })
            .collect();

        let token_v3_token = TokenV3Token {
            mint: token.mint_url,
            proofs,
        };
        TokenV3 {
            token: vec![token_v3_token],
            memo: token.memo,
            unit: Some(token.unit),
        }
    }
}

/// Token V4
#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
pub struct TokenV4 {
    /// Mint Url
    #[serde(rename = "m")]
    pub mint_url: MintUrl,
    /// Token Unit
    #[serde(rename = "u")]
    pub unit: CurrencyUnit,
    /// Memo for token
    #[serde(rename = "d", skip_serializing_if = "Option::is_none")]
    pub memo: Option<String>,
    /// Proofs grouped by keyset_id
    #[serde(rename = "t")]
    pub token: Vec<TokenV4Token>,
}

impl TokenV4 {
    /// Proofs from token
    pub fn proofs(&self, mint_keysets: &[KeySetInfo]) -> Result<Proofs, Error> {
        let mut proofs: Proofs = vec![];
        for t in self.token.iter() {
            let long_id = Id::from_short_keyset_id(&t.keyset_id, mint_keysets)?;
            proofs.extend(t.proofs.iter().map(|p| p.into_proof(&long_id)));
        }
        Ok(proofs)
    }

    /// Value - errors if duplicate proofs are found
    #[inline]
    pub fn value(&self) -> Result<Amount, Error> {
        let proofs: Vec<ProofV4> = self.token.iter().flat_map(|t| t.proofs.clone()).collect();
        let unique_count = proofs
            .iter()
            .collect::<std::collections::HashSet<_>>()
            .len();

        // Check if there are any duplicate proofs
        if unique_count != proofs.len() {
            return Err(Error::DuplicateProofs);
        }

        Ok(Amount::try_sum(
            self.token
                .iter()
                .map(|t| Amount::try_sum(t.proofs.iter().map(|p| p.amount)))
                .collect::<Result<Vec<Amount>, _>>()?,
        )?)
    }

    /// Memo
    #[inline]
    pub fn memo(&self) -> &Option<String> {
        &self.memo
    }

    /// Unit
    #[inline]
    pub fn unit(&self) -> &CurrencyUnit {
        &self.unit
    }

    /// Serialize the token to raw binary
    pub fn to_raw_bytes(&self) -> Result<Vec<u8>, Error> {
        let mut prefix = b"crawB".to_vec();
        let mut data = Vec::new();
        ciborium::into_writer(self, &mut data).map_err(Error::CiboriumSerError)?;
        prefix.extend(data);
        Ok(prefix)
    }
}

impl fmt::Display for TokenV4 {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        use serde::ser::Error;
        let mut data = Vec::new();
        ciborium::into_writer(self, &mut data).map_err(|e| fmt::Error::custom(e.to_string()))?;
        let encoded = general_purpose::URL_SAFE.encode(data);
        write!(f, "cashuB{encoded}")
    }
}

impl FromStr for TokenV4 {
    type Err = Error;

    fn from_str(s: &str) -> Result<Self, Self::Err> {
        let s = s.strip_prefix("cashuB").ok_or(Error::UnsupportedToken)?;

        let decode_config = general_purpose::GeneralPurposeConfig::new()
            .with_decode_padding_mode(bitcoin::base64::engine::DecodePaddingMode::Indifferent);
        let decoded = GeneralPurpose::new(&alphabet::URL_SAFE, decode_config).decode(s)?;
        let token: TokenV4 = ciborium::from_reader(&decoded[..])?;
        Ok(token)
    }
}

impl TryFrom<&Vec<u8>> for TokenV4 {
    type Error = Error;

    fn try_from(bytes: &Vec<u8>) -> Result<Self, Self::Error> {
        ensure_cdk!(bytes.len() >= 5, Error::UnsupportedToken);

        let prefix = String::from_utf8(bytes[..5].to_vec())?;
        ensure_cdk!(prefix.as_str() == "crawB", Error::UnsupportedToken);

        Ok(ciborium::from_reader(&bytes[5..])?)
    }
}

impl TryFrom<TokenV3> for TokenV4 {
    type Error = Error;
    fn try_from(token: TokenV3) -> Result<Self, Self::Error> {
        let mint_urls = token.mint_urls();
        let proofs: Vec<ProofV3> = token.token.into_iter().flat_map(|t| t.proofs).collect();

        ensure_cdk!(mint_urls.len() == 1, Error::UnsupportedToken);

        let mint_url = mint_urls.first().ok_or(Error::UnsupportedToken)?;

        let proofs = proofs
            .into_iter()
            .fold(
                HashMap::<ShortKeysetId, Vec<ProofV4>>::new(),
                |mut acc, val| {
                    acc.entry(val.keyset_id.clone())
                        .and_modify(|p: &mut Vec<ProofV4>| p.push(val.clone().into()))
                        .or_insert(vec![val.clone().into()]);
                    acc
                },
            )
            .into_iter()
            .map(|(id, proofs)| TokenV4Token {
                keyset_id: id,
                proofs,
            })
            .collect();

        Ok(TokenV4 {
            mint_url: mint_url.clone(),
            token: proofs,
            memo: token.memo,
            unit: token.unit.ok_or(Error::UnsupportedUnit)?,
        })
    }
}

/// Token V4 Token
#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
pub struct TokenV4Token {
    /// `Keyset id`
    #[serde(
        rename = "i",
        serialize_with = "serialize_v4_keyset_id",
        deserialize_with = "deserialize_v4_keyset_id"
    )]
    pub keyset_id: ShortKeysetId,
    /// Proofs
    #[serde(rename = "p")]
    pub proofs: Vec<ProofV4>,
}

fn serialize_v4_keyset_id<S>(keyset_id: &ShortKeysetId, serializer: S) -> Result<S::Ok, S::Error>
where
    S: serde::Serializer,
{
    serializer.serialize_bytes(&keyset_id.to_bytes())
}

fn deserialize_v4_keyset_id<'de, D>(deserializer: D) -> Result<ShortKeysetId, D::Error>
where
    D: serde::Deserializer<'de>,
{
    let bytes = Vec::<u8>::deserialize(deserializer)?;
    ShortKeysetId::from_bytes(&bytes).map_err(serde::de::Error::custom)
}

impl TokenV4Token {
    /// Create new [`TokenV4Token`]
    pub fn new(keyset_id: Id, proofs: Proofs) -> Self {
        // Create a short keyset id from id
        let short_id = ShortKeysetId::from(keyset_id);
        Self {
            keyset_id: short_id,
            proofs: proofs.into_iter().map(|p| p.into()).collect(),
        }
    }
}

#[cfg(test)]
mod tests {
    use std::str::FromStr;

    use bip39::rand::{self, RngCore};

    use super::*;
    use crate::dhke::hash_to_curve;
    use crate::mint_url::MintUrl;
    use crate::secret::Secret;
    use crate::util::hex;

    #[test]
    fn test_token_padding() {
        let token_str_with_padding = "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";

        let token = TokenV3::from_str(token_str_with_padding).unwrap();

        let token_str_without_padding = "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";

        let token_without = TokenV3::from_str(token_str_without_padding).unwrap();

        assert_eq!(token, token_without);
    }

    #[test]
    fn test_token_v4_str_round_trip() {
        let token_str = "cashuBpGF0gaJhaUgArSaMTR9YJmFwgaNhYQFhc3hAOWE2ZGJiODQ3YmQyMzJiYTc2ZGIwZGYxOTcyMTZiMjlkM2I4Y2MxNDU1M2NkMjc4MjdmYzFjYzk0MmZlZGI0ZWFjWCEDhhhUP_trhpXfStS6vN6So0qWvc2X3O4NfM-Y1HISZ5JhZGlUaGFuayB5b3VhbXVodHRwOi8vbG9jYWxob3N0OjMzMzhhdWNzYXQ=";
        let token = TokenV4::from_str(token_str).unwrap();

        assert_eq!(
            token.mint_url,
            MintUrl::from_str("http://localhost:3338").unwrap()
        );
        assert_eq!(
            token.token[0].keyset_id,
            ShortKeysetId::from_str("00ad268c4d1f5826").unwrap()
        );

        let encoded = &token.to_string();

        let token_data = TokenV4::from_str(encoded).unwrap();

        assert_eq!(token_data, token);
    }

    #[test]
    fn test_token_v4_multi_keyset() {
        let token_str_multi_keysets = "cashuBo2F0gqJhaUgA_9SLj17PgGFwgaNhYQFhc3hAYWNjMTI0MzVlN2I4NDg0YzNjZjE4NTAxNDkyMThhZjkwZjcxNmE1MmJmNGE1ZWQzNDdlNDhlY2MxM2Y3NzM4OGFjWCECRFODGd5IXVW-07KaZCvuWHk3WrnnpiDhHki6SCQh88-iYWlIAK0mjE0fWCZhcIKjYWECYXN4QDEzMjNkM2Q0NzA3YTU4YWQyZTIzYWRhNGU5ZjFmNDlmNWE1YjRhYzdiNzA4ZWIwZDYxZjczOGY0ODMwN2U4ZWVhY1ghAjRWqhENhLSsdHrr2Cw7AFrKUL9Ffr1XN6RBT6w659lNo2FhAWFzeEA1NmJjYmNiYjdjYzY0MDZiM2ZhNWQ1N2QyMTc0ZjRlZmY4YjQ0MDJiMTc2OTI2ZDNhNTdkM2MzZGNiYjU5ZDU3YWNYIQJzEpxXGeWZN5qXSmJjY8MzxWyvwObQGr5G1YCCgHicY2FtdWh0dHA6Ly9sb2NhbGhvc3Q6MzMzOGF1Y3NhdA==";

        let token = Token::from_str(token_str_multi_keysets).unwrap();
        let amount = token.value().expect("valid amount");

        assert_eq!(amount, Amount::from(4));

        let unit = token.unit().unwrap();
        assert_eq!(CurrencyUnit::Sat, unit);

        match token {
            Token::TokenV4(token) => {
                let tokens: Vec<ShortKeysetId> =
                    token.token.iter().map(|t| t.keyset_id.clone()).collect();

                assert_eq!(tokens.len(), 2);

                assert!(tokens.contains(&ShortKeysetId::from_str("00ffd48b8f5ecf80").unwrap()));
                assert!(tokens.contains(&ShortKeysetId::from_str("00ad268c4d1f5826").unwrap()));

                let mint_url = token.mint_url;

                assert_eq!("http://localhost:3338", &mint_url.to_string());
            }
            _ => {
                panic!("Token should be a v4 token")
            }
        }
    }

    #[test]
    fn test_tokenv4_from_tokenv3() {
        let token_v3_str = "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";
        let token_v3 =
            TokenV3::from_str(token_v3_str).expect("TokenV3 should be created from string");
        let token_v4 = TokenV4::try_from(token_v3).expect("TokenV3 should be converted to TokenV4");
        let token_v4_expected = "cashuBpGFtd2h0dHBzOi8vODMzMy5zcGFjZTozMzM4YXVjc2F0YWRqVGhhbmsgeW91LmF0gaJhaUgAmh8pMlPkHmFwgqRhYQJhc3hANDA3OTE1YmMyMTJiZTYxYTc3ZTNlNmQyYWViNGM3Mjc5ODBiZGE1MWNkMDZhNmFmYzI5ZTI4NjE3NjhhNzgzN2FjWCECvJCXmX2Br7LMc0a15DRak0a9KlBut5WFmKcvDPhRY-phZPakYWEIYXN4QGZlMTUxMDkzMTRlNjFkNzc1NmIwZjhlZTBmMjNhNjI0YWNhYTNmNGUwNDJmNjE0MzNjNzI4YzcwNTdiOTMxYmVhY1ghAp6OUFC4kKfWwJaNsWvB1dX6BA6h3ihPbsadYSmfZxBZYWT2";
        assert_eq!(token_v4.to_string(), token_v4_expected);
    }

    #[test]
    fn test_token_str_round_trip() {
        let token_str = "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";

        let token = TokenV3::from_str(token_str).unwrap();
        assert_eq!(
            token.token[0].mint,
            MintUrl::from_str("https://8333.space:3338").unwrap()
        );
        assert_eq!(
            token.token[0].proofs[0].clone().keyset_id,
            ShortKeysetId::from_str("009a1f293253e41e").unwrap()
        );
        assert_eq!(token.unit.clone().unwrap(), CurrencyUnit::Sat);

        let encoded = &token.to_string();

        let token_data = TokenV3::from_str(encoded).unwrap();

        assert_eq!(token_data, token);
    }

    #[test]
    fn incorrect_tokens() {
        let incorrect_prefix = "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";

        let incorrect_prefix_token = TokenV3::from_str(incorrect_prefix);

        assert!(incorrect_prefix_token.is_err());

        let no_prefix = "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";

        let no_prefix_token = TokenV3::from_str(no_prefix);

        assert!(no_prefix_token.is_err());

        let correct_token = "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";

        let correct_token = TokenV3::from_str(correct_token);

        assert!(correct_token.is_ok());
    }

    #[test]
    fn test_token_v4_raw_roundtrip() {
        let token_raw = hex::decode("6372617742a4617481a261694800ad268c4d1f5826617081a3616101617378403961366462623834376264323332626137366462306466313937323136623239643362386363313435353363643237383237666331636339343266656462346561635821038618543ffb6b8695df4ad4babcde92a34a96bdcd97dcee0d7ccf98d4721267926164695468616e6b20796f75616d75687474703a2f2f6c6f63616c686f73743a33333338617563736174").unwrap();
        let token = TokenV4::try_from(&token_raw).expect("Token deserialization error");
        let token_raw_ = token.to_raw_bytes().expect("Token serialization error");
        let token_ = TokenV4::try_from(&token_raw_).expect("Token deserialization error");
        assert!(token_ == token)
    }

    #[test]
    fn test_token_generic_raw_roundtrip() {
        let tokenv4_raw = hex::decode("6372617742a4617481a261694800ad268c4d1f5826617081a3616101617378403961366462623834376264323332626137366462306466313937323136623239643362386363313435353363643237383237666331636339343266656462346561635821038618543ffb6b8695df4ad4babcde92a34a96bdcd97dcee0d7ccf98d4721267926164695468616e6b20796f75616d75687474703a2f2f6c6f63616c686f73743a33333338617563736174").unwrap();
        let tokenv4 = Token::try_from(&tokenv4_raw).expect("Token deserialization error");
        let tokenv4_ = TokenV4::try_from(&tokenv4_raw).expect("Token deserialization error");
        let tokenv4_bytes = tokenv4.to_raw_bytes().expect("Serialization error");
        let tokenv4_bytes_ = tokenv4_.to_raw_bytes().expect("Serialization error");
        assert!(tokenv4_bytes_ == tokenv4_bytes);
    }

    #[test]
    fn test_token_with_duplicate_proofs() {
        // Create a token with duplicate proofs
        let mint_url = MintUrl::from_str("https://example.com").unwrap();
        let keyset_id = Id::from_str("009a1f293253e41e").unwrap();

        let secret = Secret::generate();
        // Create two identical proofs
        let proof1 = Proof {
            amount: Amount::from(10),
            keyset_id,
            secret: secret.clone(),
            c: "02bc9097997d81afb2cc7346b5e4345a9346bd2a506eb7958598a72f0cf85163ea"
                .parse()
                .unwrap(),
            witness: None,
            dleq: None,
        };

        let proof2 = proof1.clone(); // Duplicate proof

        // Create a token with the duplicate proofs
        let proofs = vec![proof1.clone(), proof2].into_iter().collect();
        let token = Token::new(mint_url.clone(), proofs, None, CurrencyUnit::Sat);

        // Verify that value() returns an error
        let result = token.value();
        assert!(result.is_err());

        // Create a token with unique proofs
        let proof3 = Proof {
            amount: Amount::from(10),
            keyset_id,
            secret: Secret::generate(),
            c: "03bc9097997d81afb2cc7346b5e4345a9346bd2a506eb7958598a72f0cf85163ea"
                .parse()
                .unwrap(), // Different C value
            witness: None,
            dleq: None,
        };

        let proofs = vec![proof1, proof3].into_iter().collect();
        let token = Token::new(mint_url, proofs, None, CurrencyUnit::Sat);

        // Verify that value() succeeds with unique proofs
        let result = token.value();
        assert!(result.is_ok());
        assert_eq!(result.unwrap(), Amount::from(20));
    }

    #[test]
    fn test_token_from_proofs_with_idv2_round_trip() {
        let mint_url = MintUrl::from_str("https://example.com").unwrap();

        let keysets_info: Vec<KeySetInfo> = (0..10)
            .map(|_| {
                let mut bytes: [u8; 33] = [0u8; 33];
                bytes[0] = 1u8;
                rand::thread_rng().fill_bytes(&mut bytes[1..]);
                let id = Id::from_bytes(&bytes).unwrap();
                KeySetInfo {
                    id,
                    unit: CurrencyUnit::Sat,
                    active: true,
                    input_fee_ppk: 0,
                    final_expiry: None,
                }
            })
            .collect();

        let chosen_keyset_id = keysets_info[0].id;
        // Make up a bunch of fake proofs
        let proofs = (0..5)
            .map(|_| {
                let mut c_preimage: [u8; 33] = [0u8; 33];
                c_preimage[0] = 1u8;
                rand::thread_rng().fill_bytes(&mut c_preimage[1..]);
                Proof::new(
                    Amount::from(1),
                    chosen_keyset_id,
                    Secret::generate(),
                    hash_to_curve(&c_preimage).unwrap(),
                )
            })
            .collect();

        let token = Token::new(mint_url.clone(), proofs, None, CurrencyUnit::Sat);
        let token_str = token.to_string();

        let token1 = Token::from_str(&token_str);
        assert!(token1.is_ok());

        let proofs1 = token1.unwrap().proofs(&keysets_info);
        assert!(proofs1.is_ok());

        //println!("{:?}", proofs1);
    }

    #[test]
    fn test_token_proofs_with_unknown_short_keyset_id() {
        let mint_url = MintUrl::from_str("https://example.com").unwrap();

        let keysets_info: Vec<KeySetInfo> = (0..10)
            .map(|_| {
                let mut bytes: [u8; 33] = [0u8; 33];
                bytes[0] = 1u8;
                rand::thread_rng().fill_bytes(&mut bytes[1..]);
                let id = Id::from_bytes(&bytes).unwrap();
                KeySetInfo {
                    id,
                    unit: CurrencyUnit::Sat,
                    active: true,
                    input_fee_ppk: 0,
                    final_expiry: None,
                }
            })
            .collect();

        let chosen_keyset_id =
            Id::from_str("01c352c0b47d42edb764bddf8c53d77b85f057157d92084d9d05e876251ecd8422")
                .unwrap();

        // Make up a bunch of fake proofs
        let proofs = (0..5)
            .map(|_| {
                let mut c_preimage: [u8; 33] = [0u8; 33];
                c_preimage[0] = 1u8;
                rand::thread_rng().fill_bytes(&mut c_preimage[1..]);
                Proof::new(
                    Amount::from(1),
                    chosen_keyset_id,
                    Secret::generate(),
                    hash_to_curve(&c_preimage).unwrap(),
                )
            })
            .collect();

        let token = Token::new(mint_url.clone(), proofs, None, CurrencyUnit::Sat);
        let token_str = token.to_string();

        let token1 = Token::from_str(&token_str);
        assert!(token1.is_ok());

        let proofs1 = token1.unwrap().proofs(&keysets_info);
        assert!(proofs1.is_err());
    }
}