import java.security.MessageDigest

def getMD5Hash(input) {
    if (!(input instanceof File)) {
        logger.warn("getMD5Hash(): Input is no File. Maybe you forgot file()?")
    }

    MessageDigest digest = MessageDigest.getInstance("MD5")
    digest.update(input.getBytes())
    return new BigInteger(1, digest.digest()).toString(16).padLeft(32, "0");
}

def getSHA1Hash(input) {
    if (!(input instanceof File)) {
        logger.warn("getSHA1Hash(): Input is no File. Maybe you forgot file()?")
    }

    MessageDigest digest = MessageDigest.getInstance("SHA-1")
    digest.update(input.getBytes())
    return new BigInteger(1, digest.digest()).toString(16).padLeft(40, "0");
}

def getSHA256Hash(input) {
    if (!(input instanceof File)) {
        logger.warn("getSHA256Hash(): Input is no File. Maybe you forgot file()?")
    }

    MessageDigest digest = MessageDigest.getInstance("SHA-256")
    digest.update(input.getBytes())
    return new BigInteger(1, digest.digest()).toString(16).padLeft(64, "0");
}

ext { /* hax to export the methods */
    getMD5Hash = this.&getMD5Hash
    getSHA1Hash = this.&getSHA1Hash
    getSHA256Hash = this.&getSHA256Hash
}