/*
 * Copyright (C) 2020-present ScyllaDB
 */

/*
 * SPDX-License-Identifier: LicenseRef-ScyllaDB-Source-Available-1.0
 */

#include "api/api-doc/error_injection.json.hh"
#include "api/api_init.hh"
#include <seastar/http/exception.hh>
#include "utils/error_injection.hh"
#include "utils/rjson.hh"
#include <seastar/core/future-util.hh>
#include <seastar/util/short_streams.hh>

namespace api {
using namespace seastar::httpd;

namespace hf = httpd::error_injection_json;

void set_error_injection(http_context& ctx, routes& r) {

    hf::enable_injection.set(r, [](std::unique_ptr<request> req) -> future<json::json_return_type> {
        sstring injection = req->get_path_param("injection");
        bool one_shot = req->get_query_param("one_shot") == "True";
        auto params = co_await util::read_entire_stream_contiguous(*req->content_stream);

        const size_t max_params_size = 1024 * 1024;
        if (params.size() > max_params_size) {
            // This is a hard limit, because we don't want to allocate
            // too much memory or block the thread for too long.
            throw httpd::bad_param_exception(format("Injection parameters are too long, max length is {}", max_params_size));
        }

        try {
            auto parameters = params.empty()
                ? utils::error_injection_parameters{}
                : rjson::parse_to_map<utils::error_injection_parameters>(params);

            auto& errinj = utils::get_local_injector();
            co_await errinj.enable_on_all(injection, one_shot, std::move(parameters));
        } catch (const rjson::error& e) {
            throw httpd::bad_param_exception(format("Failed to parse injections parameters: {}", e.what()));
        }
        co_return json::json_void();
    });

    hf::get_enabled_injections_on_all.set(r, [](std::unique_ptr<request> req) {
        auto& errinj = utils::get_local_injector();
        auto ret = errinj.enabled_injections_on_all();
        return make_ready_future<json::json_return_type>(ret);
    });

    hf::disable_injection.set(r, [](std::unique_ptr<request> req) {
        sstring injection = req->get_path_param("injection");

        auto& errinj = utils::get_local_injector();
        return errinj.disable_on_all(injection).then([] {
            return make_ready_future<json::json_return_type>(json::json_void());
        });
    });

    hf::read_injection.set(r, [](std::unique_ptr<request> req) -> future<json::json_return_type> {
        const sstring injection = req->get_path_param("injection");

        std::vector<error_injection_json::error_injection_info> error_injection_infos(smp::count, error_injection_json::error_injection_info{});

        co_await smp::invoke_on_all([&] {
            auto& info = error_injection_infos[this_shard_id()];
            auto& errinj = utils::get_local_injector();
            const auto enabled = errinj.is_enabled(injection);
            info.enabled = enabled;
            if (!enabled) {
                return;
            }
            std::vector<error_injection_json::mapper> parameters;
            for (const auto& p : errinj.get_injection_parameters(injection)) {
                error_injection_json::mapper param;
                param.key = p.first;
                param.value = p.second;
                parameters.push_back(std::move(param));
            }
            info.parameters = std::move(parameters);
        });

        co_return json::json_return_type(error_injection_infos);
    });

    hf::disable_on_all.set(r, [](std::unique_ptr<request> req) {
        auto& errinj = utils::get_local_injector();
        return errinj.disable_on_all().then([] {
            return make_ready_future<json::json_return_type>(json::json_void());
        });
    });

    hf::message_injection.set(r, [](std::unique_ptr<request> req) {
        sstring injection = req->get_path_param("injection");
        auto& errinj = utils::get_local_injector();
        return errinj.receive_message_on_all(injection).then([] {
            return make_ready_future<json::json_return_type>(json::json_void());
        });
    });
}

} // namespace api