// Licensed to the Apache Software Foundation (ASF) under one
// or more contributor license agreements.  See the NOTICE file
// distributed with this work for additional information
// regarding copyright ownership.  The ASF licenses this file
// to you 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 "ExecutionEngine.h"
#include "src/wrapper/VecIndex.h"

#include <memory>
#include <string>

namespace zilliz {
namespace milvus {
namespace engine {

class ExecutionEngineImpl : public ExecutionEngine {
 public:
    ExecutionEngineImpl(uint16_t dimension,
                        const std::string &location,
                        EngineType index_type,
                        MetricType metric_type,
                        int32_t nlist);

    ExecutionEngineImpl(VecIndexPtr index,
                        const std::string &location,
                        EngineType index_type,
                        MetricType metric_type,
                        int32_t nlist);

    Status AddWithIds(int64_t n, const float *xdata, const int64_t *xids) override;

    size_t Count() const override;

    size_t Size() const override;

    size_t Dimension() const override;

    size_t PhysicalSize() const override;

    Status Serialize() override;

    Status Load(bool to_cache) override;

    Status CopyToGpu(uint64_t device_id) override;

    Status CopyToCpu() override;

    ExecutionEnginePtr Clone() override;

    Status Merge(const std::string &location) override;

    Status Search(int64_t n,
                  const float *data,
                  int64_t k,
                  int64_t nprobe,
                  float *distances,
                  int64_t *labels) const override;

    ExecutionEnginePtr BuildIndex(const std::string &location, EngineType engine_type) override;

    Status Cache() override;

    Status GpuCache(uint64_t gpu_id) override;

    Status Init() override;

    EngineType IndexEngineType() const override {
        return index_type_;
    }

    MetricType IndexMetricType() const override {
        return metric_type_;
    }

    std::string GetLocation() const override {
        return location_;
    }

 private:
    VecIndexPtr CreatetVecIndex(EngineType type);

    VecIndexPtr Load(const std::string &location);

 protected:
    VecIndexPtr index_ = nullptr;
    EngineType index_type_;
    MetricType metric_type_;

    int64_t dim_;
    std::string location_;

    int32_t nlist_ = 0;
    int32_t gpu_num_ = 0;
};

} // namespace engine
} // namespace milvus
} // namespace zilliz