import cryptoUtils from '../crypto/utils.js'
import {Address} from '../types.js'
import {getAddress} from '../helpers.js'

const ALGORAND_CHECKSUM_BYTE_LENGTH = 4;
const ALGORAND_ADDRESS_LENGTH = 58;

function verifyChecksum(address: string) {
    if (address.length !== ALGORAND_ADDRESS_LENGTH) {
        return false
    } else {
        // Decode base32 Address
        const decoded = cryptoUtils.base32.b32decode(address);
        const addr = decoded.slice(0, decoded.length - ALGORAND_CHECKSUM_BYTE_LENGTH)
        const checksum = cryptoUtils.byteArray2hexStr(decoded.slice(-4) as any)

        // Hash Address - Checksum
        const code = cryptoUtils.sha512_256(cryptoUtils.byteArray2hexStr(addr as any)).substr(-ALGORAND_CHECKSUM_BYTE_LENGTH * 2);

        return code.toUpperCase() === checksum
    }
}

export default {
    isValidAddress: function (address: Address) {
        return verifyChecksum(getAddress(address))
    }
}