#ifndef BAIDU_PADDLE_SERVING_SDK_CPP_PREDICTOR_HPP
#define BAIDU_PADDLE_SERVING_SDK_CPP_PREDICTOR_HPP

namespace baidu {
namespace paddle_serving {
namespace sdk_cpp {

class MetricScope;
class Stub;
template<typename T, typename C, typename R, typename I, typename O>
class StubImpl;

template<typename Arg1, typename Arg2>
inline ::google::protobuf::Closure* NewClosure(
        void (*function)(Arg1*, Arg2*),
        Arg1* arg1 = NULL, Arg2* arg2 = NULL) {

    FunctionClosure<Arg1, Arg2>* closure = butil::get_object<
        FunctionClosure<Arg1, Arg2> >();

    if (closure) {
        if (closure->init(function, true, false, true, 
                    arg1, arg2) != 0) {
            LOG(FATAL) << "Failed create closure objects";
            return NULL;
        }
    }

    return closure;
}

template<typename Arg1, typename Arg2>
int FunctionClosure<Arg1, Arg2>::init(
        FunctionType function, bool self_deleting,
        bool arg1_deleting, bool arg2_deleting,
        Arg1* arg1, Arg2* arg2) {
    _function = function;
    _self_deleting = self_deleting;
    _arg1_deleting = arg1_deleting;
    _arg2_deleting = arg2_deleting;

    if (arg2 == NULL) {
        GET_OBJECT_FROM_POOL(_arg2, Arg2, -1);
        _arg2_deleting = true;
    }

    return 0;
}

template<typename Arg1, typename Arg2>
void FunctionClosure<Arg1, Arg2>::Run() {
    bool self_delete = _self_deleting;
    bool arg1_delete = _arg1_deleting;
    bool arg2_delete = _arg2_deleting;

    _function(_arg1, _arg2);

    if (self_delete) {
        butil::return_object(this);
    }

    if (arg2_delete) {
        butil::return_object(_arg2);
    }
}

template<typename T> int PredictorImpl<T>::init(
        google::protobuf::RpcChannel* chnl,
        T* service,
        const MethodDescriptor* infer,
        const MethodDescriptor* debug,
        const RpcParameters& options,
        Stub* stub,
        const std::string& tag) {
    MetricScope metric(stub, "rpc_init");
    butil::Timer tt(butil::Timer::STARTED);
    _service = service;
    _channel = chnl;
    _infer = infer;
    _debug = debug;
    _options = options;
    _stub = stub;
    _tag = tag;
    reset(_options, _cntl);
    _inited = true;
    return 0;
}

template<typename T> int PredictorImpl<T>::reset(
        const RpcParameters& options, 
        brpc::Controller& cntl) {
    cntl.Reset();
    if (options.compress_type.init) {
        cntl.set_request_compress_type(
                compress_types[options.compress_type.value]);
    }
    return 0;
}

template<typename T> int PredictorImpl<T>::deinit() {
    // do nothing
    _inited = false;
    return 0;
}

template<typename T> int PredictorImpl<T>::inference(
        google::protobuf::Message* req,
        google::protobuf::Message* res) {
    MetricScope metric(_stub, "infer_sync");
    _service->CallMethod(_infer, &_cntl, req, res, NULL);
    if (_cntl.Failed()) {
        LOG(WARNING) 
            << "inference call failed, message: "
            << _cntl.ErrorText();
        _stub->update_average(1, "failure");
        return -1;
    }
    return 0; 
}

template<typename T> int PredictorImpl<T>::inference(
        google::protobuf::Message* req,
        google::protobuf::Message* res,
        DoneType done,
        brpc::CallId* cid) {
    MetricScope metric(_stub, "infer_async");
    // 异步接口不能使用当前predictor的controller成员，而应该
    // 在对象池临时申请一个独立的对象，且直到异步回调执行完
    // 成后才能释放，而该释放行为被NewClosure自动托管，用户
    // 无需关注。
    brpc::Controller* cntl 
        = butil::get_object<brpc::Controller>();
    if (!cntl || reset(_options, *cntl) != 0) {
        LOG(FATAL) << "Failed get controller from object pool,"
            << "cntl is null: " << (cntl == NULL);
        _stub->update_average(1, "failure");
        return -1;
    }

    if (cid != NULL) { // you can join this rpc with cid
        *cid = cntl->call_id();
    }

    _service->CallMethod(_infer, cntl, req, res, NewClosure(
                done, res, cntl));
    return 0;
}

template<typename T> int PredictorImpl<T>::debug(
        google::protobuf::Message* req,
        google::protobuf::Message* res,
        butil::IOBufBuilder* debug_os) {
    MetricScope metric(_stub, "debug");
    _service->CallMethod(_debug, &_cntl, req, res, NULL);
    if (_cntl.Failed()) {
        LOG(WARNING) 
            << "inference call failed, message: "
            << _cntl.ErrorText();
        _stub->update_average(1, "failure");
        return -1;
    }

    // copy debug info from response attachment
    (*debug_os) << _cntl.response_attachment();
    return 0;
}

template<typename T> int PredictorImpl<T>::send_inference(
        google::protobuf::Message* req,
        google::protobuf::Message* res) {
    MetricScope metric(_stub, "infer_send");
    _inferid = _cntl.call_id();
    _service->CallMethod(
            _infer, &_cntl, req, res, brpc::DoNothing());
    return 0;
}

template<typename T> int PredictorImpl<T>::recv_inference() {
    // waiting for callback done
    MetricScope metric(_stub, "infer_recv");
    brpc::Join(_inferid);
    if (_cntl.Failed()) {
        LOG(WARNING) << "Failed recv response from rpc"
            << ", err: " << _cntl.ErrorText();
        _stub->update_average(1, "failure");
        return -1;
    }
    return 0;
}

template<typename T> void PredictorImpl<T>::cancel_inference() {
    MetricScope metric(_stub, "infer_cancel");
    brpc::StartCancel(_inferid);
}

template<typename T> const char* PredictorImpl<T>::tag() {
    return _tag.c_str();
}

} // sdk_cpp
} // paddle_serving
} // baidu

#endif  //BAIDU_PADDLE_SERVING_SDK_CPP_PREDICTORR_HPP