/* -*- Mode: C++; tab-width: 4; c-basic-offset: 4; indent-tabs-mode: nil -*- */
/*
 *   Copyright 2020-2021 Couchbase, Inc.
 *
 *   Licensed under the Apache License, Version 2.0 (the "License");
 *   you may not use this file except in compliance with the License.
 *   You may obtain a copy of the License at
 *
 *       http://www.apache.org/licenses/LICENSE-2.0
 *
 *   Unless required by applicable law or agreed to in writing, software
 *   distributed under the License is distributed on an "AS IS" BASIS,
 *   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *   See the License for the specific language governing permissions and
 *   limitations under the License.
 */

#include "client_response.hxx"

#include "core/utils/json.hxx"

#include <cstring>
#include <gsl/assert>

namespace couchbase::core::protocol
{
double
parse_server_duration_us(const io::mcbp_message& msg)
{
    if (msg.header.magic != static_cast<std::uint8_t>(magic::alt_client_response)) {
        return 0;
    }
    auto framing_extras_size = static_cast<std::uint8_t>(msg.header.keylen & 0xfU);
    if (framing_extras_size == 0) {
        return 0;
    }
    std::size_t offset = 0;
    while (offset < framing_extras_size) {
        auto frame_size = std::to_integer<std::uint8_t>(msg.body[offset] & std::byte{ 0b1111 });
        auto frame_id = std::to_integer<std::uint8_t>((msg.body[offset] >> 4U) & std::byte{ 0b1111 });
        ++offset;
        if (frame_id == static_cast<std::uint8_t>(response_frame_info_id::server_duration)) {
            if (frame_size == 2 && framing_extras_size - offset >= frame_size) {
                std::uint16_t encoded_duration{};
                std::memcpy(&encoded_duration, msg.body.data() + offset, sizeof(encoded_duration));
                encoded_duration = utils::byte_swap(encoded_duration);
                return std::pow(encoded_duration, 1.74) / 2;
            }
        }
        offset += frame_size;
    }
    return 0;
}

bool
parse_enhanced_error(std::string_view str, key_value_extended_error_info& info)
{
    if (auto error = utils::json::parse(str); error.is_object()) {
        if (const auto* err_obj = error.find("error"); err_obj != nullptr && err_obj->is_object()) {
            std::string reference;
            if (const auto* ref = err_obj->find("ref"); ref != nullptr && ref->is_string()) {
                reference = ref->get_string();
            }
            std::string context;
            if (const auto* ctx = err_obj->find("context"); ctx != nullptr && ctx->is_string()) {
                context = ctx->get_string();
            }

            info = key_value_extended_error_info{ reference, context };
            return true;
        }
    }
    return false;
}
} // namespace couchbase::core::protocol