/* -*- Mode: C++; tab-width: 4; c-basic-offset: 4; indent-tabs-mode: nil -*- */
/*
 *     Copyright 2020 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.
 */

#pragma once

#include <set>

#include <gsl/gsl_util>

#include <tao/json.hpp>
#include <spdlog/spdlog.h>
#include <utils/crc32.hxx>
#include <platform/uuid.h>

#include <service_type.hxx>
#include <capabilities.hxx>

namespace couchbase
{
struct configuration {
    enum class node_locator_type {
        unknown,
        vbucket,
        ketama,
    };

    struct port_map {
        std::optional<std::uint16_t> key_value{};
        std::optional<std::uint16_t> management{};
        std::optional<std::uint16_t> analytics{};
        std::optional<std::uint16_t> search{};
        std::optional<std::uint16_t> views{};
        std::optional<std::uint16_t> query{};
    };
    struct alternate_address {
        std::string name{};
        std::string hostname{};
        port_map services_plain{};
        port_map services_tls{};
    };
    struct node {
        bool this_node{ false };
        size_t index{};
        std::string hostname{};
        port_map services_plain{};
        port_map services_tls{};
        std::map<std::string, alternate_address> alt{};

        [[nodiscard]] std::uint16_t port_or(service_type type, bool is_tls, std::uint16_t default_value) const
        {
            if (is_tls) {
                switch (type) {
                    case service_type::query:
                        return services_tls.query.value_or(default_value);

                    case service_type::analytics:
                        return services_tls.analytics.value_or(default_value);

                    case service_type::search:
                        return services_tls.search.value_or(default_value);

                    case service_type::views:
                        return services_tls.views.value_or(default_value);

                    case service_type::management:
                        return services_tls.management.value_or(default_value);

                    case service_type::kv:
                        return services_tls.key_value.value_or(default_value);
                }
            }
            switch (type) {
                case service_type::query:
                    return services_plain.query.value_or(default_value);

                case service_type::analytics:
                    return services_plain.analytics.value_or(default_value);

                case service_type::search:
                    return services_plain.search.value_or(default_value);

                case service_type::views:
                    return services_plain.views.value_or(default_value);

                case service_type::management:
                    return services_plain.management.value_or(default_value);

                case service_type::kv:
                    return services_plain.key_value.value_or(default_value);
            }
            return default_value;
        }

        [[nodiscard]] const std::string& hostname_for(const std::string& network) const
        {
            if (network == "default") {
                return hostname;
            }
            const auto& address = alt.find(network);
            if (address == alt.end()) {
                spdlog::warn(R"(requested network "{}" is not found, fallback to "default" host)", network);
                return hostname;
            }
            return address->second.hostname;
        }

        [[nodiscard]] std::uint16_t port_or(const std::string& network, service_type type, bool is_tls, std::uint16_t default_value) const
        {
            if (network == "default") {
                return port_or(type, is_tls, default_value);
            }
            const auto& address = alt.find(network);
            if (address == alt.end()) {
                spdlog::warn(R"(requested network "{}" is not found, fallback to "default" port of {} service)", network, type);
                return port_or(type, is_tls, default_value);
            }
            if (is_tls) {
                switch (type) {
                    case service_type::query:
                        return address->second.services_tls.query.value_or(default_value);

                    case service_type::analytics:
                        return address->second.services_tls.analytics.value_or(default_value);

                    case service_type::search:
                        return address->second.services_tls.search.value_or(default_value);

                    case service_type::views:
                        return address->second.services_tls.views.value_or(default_value);

                    case service_type::management:
                        return address->second.services_tls.management.value_or(default_value);

                    case service_type::kv:
                        return address->second.services_tls.key_value.value_or(default_value);
                }
            }
            switch (type) {
                case service_type::query:
                    return address->second.services_plain.query.value_or(default_value);

                case service_type::analytics:
                    return address->second.services_plain.analytics.value_or(default_value);

                case service_type::search:
                    return address->second.services_plain.search.value_or(default_value);

                case service_type::views:
                    return address->second.services_plain.views.value_or(default_value);

                case service_type::management:
                    return address->second.services_plain.management.value_or(default_value);

                case service_type::kv:
                    return address->second.services_plain.key_value.value_or(default_value);
            }
            return default_value;
        }
    };

    [[nodiscard]] std::string select_network(const std::string& bootstrap_hostname) const
    {
        for (const auto& n : nodes) {
            if (n.this_node) {
                if (n.hostname == bootstrap_hostname) {
                    return "default";
                }
                for (const auto& entry : n.alt) {
                    if (entry.second.hostname == bootstrap_hostname) {
                        return entry.first;
                    }
                }
            }
        }
        return "default";
    }

    using vbucket_map = typename std::vector<std::vector<std::int16_t>>;

    std::optional<std::uint64_t> rev{};
    couchbase::uuid::uuid_t id{};
    std::optional<std::uint32_t> num_replicas{};
    std::vector<node> nodes{};
    std::optional<std::string> uuid{};
    std::optional<std::string> bucket{};
    std::optional<vbucket_map> vbmap{};
    std::optional<std::uint64_t> collections_manifest_uid{};
    std::set<bucket_capability> bucket_capabilities{};
    std::set<cluster_capability> cluster_capabilities{};
    node_locator_type node_locator{ node_locator_type::unknown };

    [[nodiscard]] std::string rev_str() const
    {
        return rev ? fmt::format("{}", *rev) : "(none)";
    }

    [[nodiscard]] bool supports_enhanced_prepared_statements() const
    {
        return cluster_capabilities.find(cluster_capability::n1ql_enhanced_prepared_statements) != cluster_capabilities.end();
    }

    size_t index_for_endpoint(const asio::ip::tcp::endpoint& endpoint)
    {
        auto hostname = endpoint.address().to_string();
        for (const auto& n : nodes) {
            if (n.hostname == hostname) {
                return n.index;
            }
        }
        throw std::runtime_error("unable to locate node for the index");
    }

    [[nodiscard]] std::size_t index_for_this_node() const
    {
        for (const auto& n : nodes) {
            if (n.this_node) {
                return n.index;
            }
        }
        throw std::runtime_error("no nodes marked as this_node");
    }

    std::pair<std::uint16_t, std::int16_t> map_key(const std::string& key)
    {
        if (!vbmap.has_value()) {
            throw std::runtime_error("cannot map key: partition map is not available");
        }
        uint32_t crc = utils::hash_crc32(key.data(), key.size());
        uint16_t vbucket = uint16_t(crc % vbmap->size());
        return std::make_pair(vbucket, vbmap->at(vbucket)[0]);
    }
};

configuration
make_blank_configuration(const std::string& hostname, std::uint16_t plain_port, std::uint16_t tls_port)
{
    configuration result;
    result.id = couchbase::uuid::random();
    result.rev = 0;
    result.nodes.resize(1);
    result.nodes[0].hostname = hostname;
    result.nodes[0].this_node = true;
    result.nodes[0].services_plain.key_value = plain_port;
    result.nodes[0].services_tls.key_value = tls_port;
    return result;
}
} // namespace couchbase

template<>
struct fmt::formatter<couchbase::configuration::node> : formatter<std::string> {
    template<typename FormatContext>
    auto format(const couchbase::configuration::node& node, FormatContext& ctx)
    {
        std::vector<std::string> plain;
        if (node.services_plain.key_value) {
            plain.push_back(fmt::format("kv={}", *node.services_plain.key_value));
        }
        if (node.services_plain.management) {
            plain.push_back(fmt::format("mgmt={}", *node.services_plain.management));
        }
        if (node.services_plain.analytics) {
            plain.push_back(fmt::format("cbas={}", *node.services_plain.analytics));
        }
        if (node.services_plain.search) {
            plain.push_back(fmt::format("fts={}", *node.services_plain.search));
        }
        if (node.services_plain.query) {
            plain.push_back(fmt::format("n1ql={}", *node.services_plain.query));
        }
        if (node.services_plain.views) {
            plain.push_back(fmt::format("capi={}", *node.services_plain.views));
        }
        std::vector<std::string> tls;
        if (node.services_tls.key_value) {
            tls.push_back(fmt::format("kv={}", *node.services_tls.key_value));
        }
        if (node.services_tls.management) {
            tls.push_back(fmt::format("mgmt={}", *node.services_tls.management));
        }
        if (node.services_tls.analytics) {
            tls.push_back(fmt::format("cbas={}", *node.services_tls.analytics));
        }
        if (node.services_tls.search) {
            tls.push_back(fmt::format("fts={}", *node.services_tls.search));
        }
        if (node.services_tls.query) {
            tls.push_back(fmt::format("n1ql={}", *node.services_tls.query));
        }
        if (node.services_tls.views) {
            tls.push_back(fmt::format("capi={}", *node.services_tls.views));
        }
        std::vector<std::string> alternate_addresses{};
        if (!node.alt.empty()) {
            alternate_addresses.reserve(node.alt.size());
            for (const auto& entry : node.alt) {
                std::string network = fmt::format(R"(name="{}", host="{}")", entry.second.name, entry.second.hostname);
                {
                    std::vector<std::string> ports;
                    if (entry.second.services_plain.key_value) {
                        ports.push_back(fmt::format("kv={}", *entry.second.services_plain.key_value));
                    }
                    if (entry.second.services_plain.management) {
                        ports.push_back(fmt::format("mgmt={}", *entry.second.services_plain.management));
                    }
                    if (entry.second.services_plain.analytics) {
                        ports.push_back(fmt::format("cbas={}", *entry.second.services_plain.analytics));
                    }
                    if (entry.second.services_plain.search) {
                        ports.push_back(fmt::format("fts={}", *entry.second.services_plain.search));
                    }
                    if (entry.second.services_plain.query) {
                        ports.push_back(fmt::format("n1ql={}", *entry.second.services_plain.query));
                    }
                    if (entry.second.services_plain.views) {
                        ports.push_back(fmt::format("capi={}", *entry.second.services_plain.views));
                    }
                    if (!ports.empty()) {
                        network += fmt::format(", plain=({})", fmt::join(ports, ","));
                    }
                }
                {
                    std::vector<std::string> ports;
                    if (entry.second.services_tls.key_value) {
                        ports.push_back(fmt::format("kv={}", *entry.second.services_tls.key_value));
                    }
                    if (entry.second.services_tls.management) {
                        ports.push_back(fmt::format("mgmt={}", *entry.second.services_tls.management));
                    }
                    if (entry.second.services_tls.analytics) {
                        ports.push_back(fmt::format("cbas={}", *entry.second.services_tls.analytics));
                    }
                    if (entry.second.services_tls.search) {
                        ports.push_back(fmt::format("fts={}", *entry.second.services_tls.search));
                    }
                    if (entry.second.services_tls.query) {
                        ports.push_back(fmt::format("n1ql={}", *entry.second.services_tls.query));
                    }
                    if (entry.second.services_tls.views) {
                        ports.push_back(fmt::format("capi={}", *entry.second.services_tls.views));
                    }
                    if (!ports.empty()) {
                        network += fmt::format(", tls=({})", fmt::join(ports, ","));
                    }
                }
                alternate_addresses.emplace_back(network);
            }
        }
        format_to(ctx.out(),
                  R"(#<node:{} hostname="{}", plain=({}), tls=({}), alt=[{}]>)",
                  node.index,
                  node.hostname,
                  fmt::join(plain, ", "),
                  fmt::join(tls, ", "),
                  fmt::join(alternate_addresses, ", "));
        return formatter<std::string>::format("", ctx);
    }
};

template<>
struct fmt::formatter<couchbase::configuration> : formatter<std::string> {
    template<typename FormatContext>
    auto format(const couchbase::configuration& config, FormatContext& ctx)
    {
        format_to(ctx.out(),
                  R"(#<config:{} rev={}{}{}{}{}, nodes({})=[{}], bucket_caps=[{}], cluster_caps=[{}]>)",
                  couchbase::uuid::to_string(config.id),
                  config.rev_str(),
                  config.uuid ? fmt::format(", uuid={}", *config.uuid) : "",
                  config.bucket ? fmt::format(", bucket={}", *config.bucket) : "",
                  config.num_replicas ? fmt::format(", replicas={}", *config.num_replicas) : "",
                  config.vbmap.has_value() ? fmt::format(", partitions={}", config.vbmap->size()) : "",
                  config.nodes.size(),
                  fmt::join(config.nodes, ", "),
                  fmt::join(config.bucket_capabilities, ", "),
                  fmt::join(config.cluster_capabilities, ", "));
        return formatter<std::string>::format("", ctx);
    }
};

namespace tao::json
{
template<>
struct traits<couchbase::configuration> {
    template<template<typename...> class Traits>
    static couchbase::configuration as(const tao::json::basic_value<Traits>& v)
    {
        couchbase::configuration result;
        result.id = couchbase::uuid::random();
        result.rev = v.template optional<std::uint64_t>("rev");
        auto* node_locator = v.find("nodeLocator");
        if (node_locator != nullptr && node_locator->is_string()) {
            if (node_locator->get_string() == "ketama") {
                result.node_locator = couchbase::configuration::node_locator_type::ketama;
            } else {
                result.node_locator = couchbase::configuration::node_locator_type::vbucket;
            }
        }
        auto* nodes_ext = v.find("nodesExt");
        if (nodes_ext != nullptr) {
            size_t index = 0;
            for (const auto& j : nodes_ext->get_array()) {
                couchbase::configuration::node n;
                n.index = index++;
                const auto& o = j.get_object();
                const auto& this_node = o.find("thisNode");
                if (this_node != o.end() && this_node->second.get_boolean()) {
                    n.this_node = true;
                }
                const auto& hostname = o.find("hostname");
                if (hostname != o.end()) {
                    n.hostname = hostname->second.get_string();
                    n.hostname = n.hostname.substr(0, n.hostname.rfind(":"));
                }
                const auto& s = o.at("services");
                n.services_plain.key_value = s.template optional<std::uint16_t>("kv");
                n.services_plain.management = s.template optional<std::uint16_t>("mgmt");
                n.services_plain.search = s.template optional<std::uint16_t>("fts");
                n.services_plain.analytics = s.template optional<std::uint16_t>("cbas");
                n.services_plain.query = s.template optional<std::uint16_t>("n1ql");
                n.services_plain.views = s.template optional<std::uint16_t>("capi");
                n.services_tls.key_value = s.template optional<std::uint16_t>("kvSSL");
                n.services_tls.management = s.template optional<std::uint16_t>("mgmtSSL");
                n.services_tls.search = s.template optional<std::uint16_t>("ftsSSL");
                n.services_tls.analytics = s.template optional<std::uint16_t>("cbasSSL");
                n.services_tls.query = s.template optional<std::uint16_t>("n1qlSSL");
                n.services_tls.views = s.template optional<std::uint16_t>("capiSSL");
                {
                    const auto& alt = o.find("alternateAddresses");
                    if (alt != o.end()) {
                        for (const auto& entry : alt->second.get_object()) {
                            couchbase::configuration::alternate_address addr;
                            addr.name = entry.first;
                            addr.hostname = entry.second.at("hostname").get_string();
                            const auto& ports = entry.second.find("ports");
                            addr.services_plain.key_value = ports->template optional<std::uint16_t>("kv");
                            addr.services_plain.management = ports->template optional<std::uint16_t>("mgmt");
                            addr.services_plain.search = ports->template optional<std::uint16_t>("fts");
                            addr.services_plain.analytics = ports->template optional<std::uint16_t>("cbas");
                            addr.services_plain.query = ports->template optional<std::uint16_t>("n1ql");
                            addr.services_plain.views = ports->template optional<std::uint16_t>("capi");
                            addr.services_tls.key_value = ports->template optional<std::uint16_t>("kvSSL");
                            addr.services_tls.management = ports->template optional<std::uint16_t>("mgmtSSL");
                            addr.services_tls.search = ports->template optional<std::uint16_t>("ftsSSL");
                            addr.services_tls.analytics = ports->template optional<std::uint16_t>("cbasSSL");
                            addr.services_tls.query = ports->template optional<std::uint16_t>("n1qlSSL");
                            addr.services_tls.views = ports->template optional<std::uint16_t>("capiSSL");
                            n.alt.emplace(entry.first, addr);
                        }
                    }
                }
                result.nodes.emplace_back(n);
            }
        } else {
            if (result.node_locator == couchbase::configuration::node_locator_type::vbucket) {
                const auto* m = v.find("vBucketServerMap");
                const auto& nodes = v.at("nodes").get_array();
                if (m != nullptr) {
                    const auto* s = m->find("serverList");
                    size_t index = 0;
                    if (s != nullptr && s->is_array()) {
                        for (const auto& j : s->get_array()) {
                            couchbase::configuration::node n;
                            n.index = index++;
                            const auto& address = j.get_string();
                            n.hostname = address.substr(0, address.rfind(':'));
                            n.services_plain.key_value = std::stoul(address.substr(address.rfind(':') + 1));
                            if (n.index >= nodes.size()) {
                                continue;
                            }
                            const auto& np = nodes[n.index];
                            if (np.is_object()) {
                                const auto& o = np.get_object();
                                const auto& this_node = o.find("thisNode");
                                if (this_node != o.end() && this_node->second.get_boolean()) {
                                    n.this_node = true;
                                }
                                const auto& p = o.at("ports");
                                std::optional<std::int64_t> https_views = p.template optional<std::int64_t>("httpsCAPI");
                                if (https_views && https_views.value() > 0 &&
                                    https_views.value() < std::numeric_limits<std::uint16_t>::max()) {
                                    n.services_tls.views = static_cast<std::uint16_t>(https_views.value());
                                }
                                auto https_mgmt = p.template optional<std::int64_t>("httpsMgmt");
                                if (https_mgmt && https_mgmt.value() > 0 &&
                                    https_mgmt.value() < std::numeric_limits<std::uint16_t>::max()) {
                                    n.services_tls.management = static_cast<std::uint16_t>(https_mgmt.value());
                                }
                                const auto& h = o.at("hostname").get_string();
                                n.services_plain.management = std::stoul(h.substr(h.rfind(':') + 1));
                                std::string capi = o.at("couchApiBase").get_string();
                                auto slash = capi.rfind('/');
                                auto colon = capi.rfind(':', slash);
                                n.services_plain.views = std::stoul(capi.substr(colon + 1, slash));
                            }
                            result.nodes.emplace_back(n);
                        }
                    }
                }
            } else {
                size_t index = 0;
                for (const auto& node : v.at("nodes").get_array()) {
                    couchbase::configuration::node n;
                    n.index = index++;
                    const auto& o = node.get_object();
                    const auto& this_node = o.find("thisNode");
                    if (this_node != o.end() && this_node->second.get_boolean()) {
                        n.this_node = true;
                    }
                    const auto& p = o.at("ports");
                    std::optional<std::int64_t> direct = p.template optional<std::int64_t>("direct");
                    if (direct && direct.value() > 0 && direct.value() < std::numeric_limits<std::uint16_t>::max()) {
                        n.services_plain.key_value = static_cast<std::uint16_t>(direct.value());
                    }
                    std::optional<std::int64_t> https_views = p.template optional<std::int64_t>("httpsCAPI");
                    if (https_views && https_views.value() > 0 && https_views.value() < std::numeric_limits<std::uint16_t>::max()) {
                        n.services_tls.views = static_cast<std::uint16_t>(https_views.value());
                    }
                    auto https_mgmt = p.template optional<std::int64_t>("httpsMgmt");
                    if (https_mgmt && https_mgmt.value() > 0 && https_mgmt.value() < std::numeric_limits<std::uint16_t>::max()) {
                        n.services_tls.management = static_cast<std::uint16_t>(https_mgmt.value());
                    }
                    const auto& h = o.at("hostname").get_string();
                    auto colon = h.rfind(':');
                    n.hostname = h.substr(0, colon);
                    n.services_plain.management = std::stoul(h.substr(colon + 1));

                    std::string capi = o.at("couchApiBase").get_string();
                    auto slash = capi.rfind('/');
                    colon = capi.rfind(':', slash);
                    n.services_plain.views = std::stoul(capi.substr(colon + 1, slash));

                    result.nodes.emplace_back(n);
                }
            }
        }
        {
            const auto m = v.find("uuid");
            if (m != nullptr) {
                result.uuid = m->get_string();
            }
        }
        {
            const auto m = v.find("collectionsManifestUid");
            if (m != nullptr) {
                result.collections_manifest_uid = std::stoull(m->get_string(), 0, 16);
            }
        }
        {
            const auto m = v.find("name");
            if (m != nullptr) {
                result.bucket = m->get_string();
            }
        }
        {
            const auto m = v.find("vBucketServerMap");
            if (m != nullptr) {
                const auto& o = m->get_object();
                {
                    const auto f = o.find("numReplicas");
                    if (f != o.end()) {
                        result.num_replicas = f->second.template as<std::uint32_t>();
                    }
                }
                {
                    const auto f = o.find("vBucketMap");
                    if (f != o.end()) {
                        const auto& vb = f->second.get_array();
                        couchbase::configuration::vbucket_map vbmap;
                        vbmap.resize(vb.size());
                        for (size_t i = 0; i < vb.size(); i++) {
                            const auto& p = vb[i].get_array();
                            vbmap[i].resize(p.size());
                            for (size_t n = 0; n < p.size(); n++) {
                                vbmap[i][n] = p[n].template as<std::int16_t>();
                            }
                        }
                        result.vbmap = vbmap;
                    }
                }
            }
        }
        {
            const auto m = v.find("bucketCapabilities");
            if (m != nullptr && m->is_array()) {
                for (const auto& entry : m->get_array()) {
                    const auto& name = entry.get_string();
                    if (name == "couchapi") {
                        result.bucket_capabilities.insert(couchbase::bucket_capability::couchapi);
                    } else if (name == "collections") {
                        result.bucket_capabilities.insert(couchbase::bucket_capability::collections);
                    } else if (name == "durableWrite") {
                        result.bucket_capabilities.insert(couchbase::bucket_capability::durable_write);
                    } else if (name == "tombstonedUserXAttrs") {
                        result.bucket_capabilities.insert(couchbase::bucket_capability::tombstoned_user_xattrs);
                    } else if (name == "dcp") {
                        result.bucket_capabilities.insert(couchbase::bucket_capability::dcp);
                    } else if (name == "cbhello") {
                        result.bucket_capabilities.insert(couchbase::bucket_capability::cbhello);
                    } else if (name == "touch") {
                        result.bucket_capabilities.insert(couchbase::bucket_capability::touch);
                    } else if (name == "cccp") {
                        result.bucket_capabilities.insert(couchbase::bucket_capability::cccp);
                    } else if (name == "xdcrCheckpointing") {
                        result.bucket_capabilities.insert(couchbase::bucket_capability::xdcr_checkpointing);
                    } else if (name == "nodesExt") {
                        result.bucket_capabilities.insert(couchbase::bucket_capability::nodes_ext);
                    } else if (name == "xattr") {
                        result.bucket_capabilities.insert(couchbase::bucket_capability::xattr);
                    }
                }
            }
        }
        {
            const auto m = v.find("clusterCapabilities");
            if (m != nullptr && m->is_object()) {
                const auto nc = m->find("n1ql");
                if (nc != nullptr && nc->is_array()) {
                    for (const auto& entry : nc->get_array()) {
                        const auto& name = entry.get_string();
                        if (name == "costBasedOptimizer") {
                            result.cluster_capabilities.insert(couchbase::cluster_capability::n1ql_cost_based_optimizer);
                        } else if (name == "indexAdvisor") {
                            result.cluster_capabilities.insert(couchbase::cluster_capability::n1ql_index_advisor);
                        } else if (name == "javaScriptFunctions") {
                            result.cluster_capabilities.insert(couchbase::cluster_capability::n1ql_javascript_functions);
                        } else if (name == "inlineFunctions") {
                            result.cluster_capabilities.insert(couchbase::cluster_capability::n1ql_inline_functions);
                        } else if (name == "enhancedPreparedStatements") {
                            result.cluster_capabilities.insert(couchbase::cluster_capability::n1ql_enhanced_prepared_statements);
                        }
                    }
                }
            }
        }
        return result;
    }
};
} // namespace tao::json