//! ERC-20 Token辅助模块

use serde::{Deserialize, Serialize};

/// ERC-20 Token信息
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct ERC20Token {
    /// 合约地址
    pub address: String,
    /// Token符号
    pub symbol: String,
    /// Token名称
    pub name: String,
    /// 小数位数
    pub decimals: u8,
    /// 总供应量
    pub total_supply: Option<u128>,
}

impl ERC20Token {
    /// 创建新的ERC-20 Token
    pub fn new(
        address: String,
        symbol: String,
        name: String,
        decimals: u8,
    ) -> Self {
        Self {
            address,
            symbol,
            name,
            decimals,
            total_supply: None,
        }
    }
    
    /// 常见的ERC-20 Token列表
    pub fn common_tokens() -> Vec<ERC20Token> {
        vec![
            ERC20Token::new(
                "0xdac17f958d2ee523a2206206994597c13d831ec7".to_string(),
                "USDT".to_string(),
                "Tether USD".to_string(),
                6,
            ),
            ERC20Token::new(
                "0xa0b86991c6218b36c1d19d4a2e9eb0ce3606eb48".to_string(),
                "USDC".to_string(),
                "USD Coin".to_string(),
                6,
            ),
            ERC20Token::new(
                "0x6b175474e89094c44da98b954eedeac495271d0f".to_string(),
                "DAI".to_string(),
                "Dai Stablecoin".to_string(),
                18,
            ),
            ERC20Token::new(
                "0x2260fac5e5542a773aa44fbcfedf7c193bc2c599".to_string(),
                "WBTC".to_string(),
                "Wrapped BTC".to_string(),
                8,
            ),
        ]
    }
}

#[cfg(test)]
mod tests {
    use super::*;
    
    #[test]
    fn test_erc20_token_creation() {
        let token = ERC20Token::new(
            "0x1234...".to_string(),
            "TEST".to_string(),
            "Test Token".to_string(),
            18,
        );
        
        assert_eq!(token.symbol, "TEST");
        assert_eq!(token.decimals, 18);
    }
    
    #[test]
    fn test_common_tokens() {
        let tokens = ERC20Token::common_tokens();
        assert!(tokens.len() >= 4);
        
        let usdt = tokens.iter().find(|t| t.symbol == "USDT");
        assert!(usdt.is_some());
        assert_eq!(usdt.unwrap().decimals, 6);
    }
}