/*
 * Copyright (c) 2019-2023, NVIDIA CORPORATION.  All rights reserved.
 *
 * 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 <vector>

#include "src/fastertransformer/kernels/add_residual_kernels.h"
#include "src/fastertransformer/kernels/layernorm_kernels.h"
#include "src/fastertransformer/layers/BaseLayer.h"
#include "src/fastertransformer/layers/FfnLayer.h"
#include "src/fastertransformer/layers/attention_layers/BaseAttentionLayer.h"
#include "src/fastertransformer/models/llama/LlamaDecoderLayerWeight.h"
#include "src/fastertransformer/utils/Tensor.h"
#include "src/fastertransformer/utils/allocator.h"
#include "src/fastertransformer/utils/cublasMMWrapper.h"
#include "src/fastertransformer/utils/custom_ar_comm.h"
#include "src/fastertransformer/utils/nccl_utils.h"

namespace fastertransformer {

template<typename T>
class LlamaDecoder: public BaseLayer {
private:
protected:
    void         allocateBuffer() override;
    void         allocateBuffer(size_t batch_size);
    void         freeBuffer() override;
    bool         isValidLayerParallelId(uint l);
    bool         isFirstLayerParallelId(uint l);
    bool         isLastLayerParallelId(uint l);
    int          getFirstLayerParallelId();
    virtual void initialize();

    // meta data
    size_t head_num_;
    size_t size_per_head_;
    size_t inter_size_;
    size_t num_layer_;
    size_t rotary_embedding_dim_;
    bool   neox_rotary_style_;
    bool   use_gptj_residual_;
    size_t hidden_units_;
    float  layernorm_eps_;

    NcclParam tensor_para_;
    NcclParam pipeline_para_;

    std::shared_ptr<AbstractCustomComm> custom_all_reduce_comm_;
    int                                 enable_custom_all_reduce_;

    T* decoder_normed_input_ = nullptr;
    T* self_attn_output_     = nullptr;
    T* ffn_output_           = nullptr;
    T* decoder_layer_output_ = nullptr;

    BaseAttentionLayer<T>* self_attention_layer_;
    FfnLayer<T>*           ffn_layer_;

    int int8_mode_ = 0;

public:
    LlamaDecoder(size_t                              head_num,
                 size_t                              size_per_head,
                 size_t                              inter_size,
                 size_t                              num_layer,
                 size_t                              rotary_embedding_dim,
                 bool                                neox_rotary_style,
                 bool                                use_gptj_residual,
                 float                               layernorm_eps,
                 NcclParam                           tensor_para,
                 NcclParam                           pipeline_para,
                 cudaStream_t                        stream,
                 cublasMMWrapper*                    cublas_wrapper,
                 IAllocator*                         allocator,
                 bool                                is_free_buffer_after_forward,
                 int                                 int8_mode                 = 0,
                 std::shared_ptr<AbstractCustomComm> custom_all_reduce_comm    = nullptr,
                 int                                 enable_custom_all_reduce_ = 0);

    LlamaDecoder(LlamaDecoder<T> const& decoder);

    virtual ~LlamaDecoder();

    virtual void forward(std::unordered_map<std::string, Tensor>*          output_tensors,
                         const std::unordered_map<std::string, Tensor>*    input_tensors,
                         const std::vector<LlamaDecoderLayerWeight<T>*>* decoder_layer_weights);

    virtual void forward(std::vector<Tensor>*                              output_tensors,
                         const std::vector<Tensor>*                        input_tensors,
                         const std::vector<LlamaDecoderLayerWeight<T>*>* decoder_layer_weights);
};

}  // namespace fastertransformer
