@use crate::data::RPC;
@use crate::generators::cpp_s::*;
@use super::cpp_server_json_cxx;

@(header_name: &str, rpc: &RPC)
#include "@header_name"
#include <corvusoft/restbed/session.hpp>
#include <corvusoft/restbed/resource.hpp>
#include <corvusoft/restbed/request.hpp>

using namespace mrpc;

@:cpp_server_json_cxx(rpc)

template<typename T>
void send_msg(const std::shared_ptr<restbed::Session> &c, const T &v) @{
    if (c->is_closed())
        return;
    rapidjson::StringBuffer s;
    mrpc::MRPCJWriter writer@{s@};
    v >> writer;
    const auto body_ptr = s.GetString();
    const auto body = restbed::Bytes@{body_ptr, body_ptr+s.GetLength()@};
    c->yield(
        200,
        body,
        std::multimap<std::string, std::string>@{
            @{"Content-Type", "application/json"@},
            @{"Content-Length", std::to_string(body.size())@}
        @}
    );
@}

template<typename T>
void send_sse_msg(const std::shared_ptr<restbed::Session> &c, const T &v) @{
    if (c->is_closed())
        return;
    rapidjson::StringBuffer s;
    std::memcpy(s.Push(5), "data:", 5);
    mrpc::MRPCJWriter writer@{s@};
    v >> writer;
    std::memcpy(s.Push(2), "\n\n", 2);
    const auto body_ptr = s.GetString();
    const auto body = restbed::Bytes@{body_ptr, body_ptr+s.GetLength()@};
    c->yield(body);
@}

mrpc::MRPCStreamImpl::MRPCStreamImpl(const std::shared_ptr<restbed::Session> &conn) : conn(conn) @{
    conn->yield(
        200,
        std::multimap<std::string, std::string>@{
		    @{"Cache-Control", "no-cache"@},
		    @{"Content-Type", "text/event-stream"@}
        @}
    );
@}

void mrpc::MRPCStreamImpl::close() const noexcept @{ conn->close("data:null\n\n"); @}
bool mrpc::MRPCStreamImpl::is_open() const noexcept @{ return conn->is_open(); @}
@for s in streams_required(rpc) {template<> void MRPCStream<@s>::send(const @s &v) const noexcept @{ send_sse_msg(conn, v); @}
}

mrpc::MRPCServer::MRPCServer(std::shared_ptr<restbed::Resource> &r) @{
    r->set_method_handler("POST", [this](const std::shared_ptr<restbed::Session>& s) @{
        const auto req = s->get_request();
        const auto body_len = req->get_header("Content-Length", 0);
        s->fetch(body_len, [this](const std::shared_ptr<restbed::Session> &s, auto &&body) @{
            try @{ msg_handler(s, body); @}
            catch (const std::exception &_) @{ s->close(400); @}
        @});
    @});
@}

void mrpc::MRPCServer::msg_handler(const std::shared_ptr<restbed::Session> __c, const restbed::Bytes &__msg) @{
    rapidjson::Document __j;
    __j.Parse((const char*)__msg.data(), __msg.size());
    if (__j.HasParseError())
        throw std::exception@{@};
    std::string __service, __method;
    __service << json_get(__j, "service");
    __method << json_get(__j, "method");
    auto __data_member = __j.FindMember("data");
    if (__data_member == __j.MemberEnd() || !__data_member->value.IsObject())
        throw std::exception@{@};
    auto &__data = __data_member->value;
@for (si, s) in rpc.services.iter().enumerate() {@if si > 0 { else }else{    }if (__service == "@s.name") @{
@for (mi, m) in s.methods.iter().enumerate() {@if mi > 0 { else }else{        }if (__method == "@m.name") @{
            @if m.ret_stream {auto __stream = MRPCStream<@ty_to_str(m.ret.as_ref().unwrap())>@{__c@};
            }
@for (name, ty) in m.args.iter().map(|a| (&a.name, ty_to_str(&a.ty))) {            @ty @name; @name << json_get(__data, "@name");
            }
            @if m.ret_stream || m.ret.is_none() {@(s.name)_@(m.name)(@call_args(m));}
            else {send_msg(__c, @(s.name)_@(m.name)(@call_args(m)));}
        @}}
        else @{ throw std::exception@{@}; @}
    @}}
    else @{ throw std::exception@{@}; @}
@}
@}