/*
 * Copyright (C) 2015 Cloudius Systems, Ltd.
 */

#include "byte_ordered_partitioner.hh"
#include "utils/class_registrator.hh"

namespace dht {

token byte_ordered_partitioner::get_random_token()
{
    bytes b(bytes::initialized_later(), 16);
    *unaligned_cast<uint64_t>(b.begin()) = dht::get_random_number<uint64_t>();
    *unaligned_cast<uint64_t>(b.begin() + 8) = dht::get_random_number<uint64_t>();
    return token(token::kind::key, std::move(b));
}

std::map<token, float> byte_ordered_partitioner::describe_ownership(const std::vector<token>& sorted_tokens)
{
    throw std::runtime_error("not implemented");
}

token byte_ordered_partitioner::midpoint(const token& t1, const token& t2) const
{
    throw std::runtime_error("not implemented");
}

unsigned
byte_ordered_partitioner::shard_of(const token& t) const {
    if (t._data.empty()) {
        return 0;
    }
    // treat first byte as a fraction in the range [0, 1) and divide it evenly:
    return (uint8_t(t._data[0]) * smp::count) >> 8;
}

using registry = class_registrator<i_partitioner, byte_ordered_partitioner>;
static registry registrator("org.apache.cassandra.dht.ByteOrderedPartitioner");
static registry registrator_short_name("ByteOrderedPartitioner");

}