cw20base.cws

contract CW20Base {    

    error InvalidZeroAmount(Hello, There)
    error Unauthorized()

    event Transfer(sender: Addr, recipient: Addr, amount: Uint128)
    event Burn(sender: Addr, amount: Uint128)
    event Mint(minter: Addr, recipient: Addr, amount: Uint128)
    event Send(sender: Addr, contract: Addr, amount: Uint128)

    struct TokenInfo {
        name: String,
        symbol: String,
        decimals: u8,
        total_supply: Uint128,
    }

    state {
        token_info: TokenInfo
        balances[Addr]: Uint128
    }
    
    instantiate(
        name: String,
        symbol: String,
        decimals: u8,
        initial_balances: struct Cw20Coin { address: Addr, amount: Uint128 }[],
        mint?: String
    ) {
        let total_supply: Uint128 = Uint128(0)
        for { address, amount } in initial_balances {
            state.balances[address] += amount
            total_supply += amount
        }

        state.token_info = TokenInfo {
            name: name,
            symbol: symbol,
            decimals: decimals,
            total_supply: total_supply,
        }
    }

    exec transfer(recipient: Addr, amount: Uint128) {
        state.balances[msg.sender] -= amount
        state.balances[recipient] += amount
        emit Transfer(msg.sender, recipient, amount)
    }

    exec burn(amount: Uint128) {
        state.balances[msg.sender] -= amount
        state.token_info.total_supply -= amount
        emit Burn(msg.sender, amount)
    }


    exec send(contract_addr: Addr, amount: Uint128, msg: Binary) {
        state.balances[msg.sender] -= amount
        state.balances[contract_addr] += amount
        emit Send(msg.sender, contract_addr, amount) 
    }

    query balance(address: Addr) -> struct BalanceResponse { balance: Uint128 } {
        return _ {
            balance: state.balances[address] or 0
        }
    }

    query token_info() -> struct TokenInfoResponse { token_info: TokenInfo } {
        return _ {
            token_info: state.token_info
        }
    }

}