// Copyright (c) 2024 PaddlePaddle Authors. 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.

#include <stdio.h>
#include <string.h>
#include <sys/ipc.h>
#include <sys/msg.h>
#include <sys/types.h>
#include "paddle/extension.h"

#ifndef PD_BUILD_STATIC_OP
#define PD_BUILD_STATIC_OP(name) PD_BUILD_OP(static_op_##name)
#endif

#define MAX_BSZ 256
#define MAX_DRAFT_TOKENS 6

struct msgdata {
    long mtype;
    int mtext[MAX_BSZ * MAX_DRAFT_TOKENS + MAX_BSZ +
              2];  // stop_flag, bsz, tokens
};

void SpeculateSaveWithOutputMsg(const paddle::Tensor& accept_tokens,
                                const paddle::Tensor& accept_num,
                                const paddle::Tensor& not_need_stop,
                                int64_t rank_id,
                                int msg_queue_id,
                                int save_each_rank) {
    // printf("enter save output");
    if (!save_each_rank && rank_id > 0) {
        return;
    }

    int max_draft_tokens = accept_tokens.shape()[1];

    auto accept_tokens_cpu = accept_tokens.copy_to(paddle::CPUPlace(), true);
    auto accept_num_cpu = accept_num.copy_to(paddle::CPUPlace(), true);
    int64_t* accept_tokens_data = accept_tokens_cpu.data<int64_t>();
    int* accept_num_data = accept_num_cpu.data<int>();

    if (const char* inference_msg_queue_id_env_p =
            std::getenv("INFERENCE_MSG_QUEUE_ID")) {
        std::string inference_msg_queue_id_env_str(
            inference_msg_queue_id_env_p);
        int inference_msg_queue_id_from_env =
            std::stoi(inference_msg_queue_id_env_str);
#ifdef GET_OUTPUT_DEBUG
        std::cout << "Your INFERENCE_MSG_QUEUE_ID is: "
                  << inference_msg_queue_id_from_env << std::endl;
#endif
        msg_queue_id = inference_msg_queue_id_from_env;
    }
    static struct msgdata msg_sed;
    static key_t key = ftok("./", msg_queue_id);
    static int msgid = msgget(key, IPC_CREAT | 0666);

    msg_sed.mtype = 1;
    bool not_need_stop_data = not_need_stop.data<bool>()[0];

    int inference_msg_id_from_env = 1;
    if (const char* inference_msg_id_env_p = std::getenv("INFERENCE_MSG_ID")) {
        std::string inference_msg_id_env_str(inference_msg_id_env_p);
        inference_msg_id_from_env = std::stoi(inference_msg_id_env_str);
        if (inference_msg_id_from_env == 2) {
            // 2 and -2 is preserve for no-output indication.
            throw std::runtime_error(
                " INFERENCE_MSG_ID cannot be 2, please use other number.");
        }
        if (inference_msg_id_from_env < 0) {
            throw std::runtime_error(
                " INFERENCE_MSG_ID cannot be negative, please use other "
                "number.");
        }

#ifdef SAVE_WITH_OUTPUT_DEBUG
        std::cout << "Your INFERENCE_MSG_ID is: " << inference_msg_id_from_env
                  << std::endl;
#endif
    } else {
#ifdef SAVE_WITH_OUTPUT_DEBUG
        std::cout
            << "Failed to got INFERENCE_MSG_ID at env, use (int)1 as default."
            << std::endl;
#endif
    }

    msg_sed.mtext[0] = not_need_stop_data ? inference_msg_id_from_env
                                          : -inference_msg_id_from_env;
    int bsz = accept_tokens.shape()[0];
    msg_sed.mtext[1] = bsz;

    for (int i = 2; i < MAX_BSZ + 2; i++) {
        if (i - 2 >= bsz) {
            msg_sed.mtext[i] = 0;
        } else {
            msg_sed.mtext[i] = (int)accept_num_data[i - 2];
        }
    }
    for (int i = MAX_BSZ + 2; i < MAX_BSZ * MAX_DRAFT_TOKENS + MAX_BSZ + 2;
         i++) {
        int token_id = i - MAX_BSZ - 2;
        int bid = token_id / MAX_DRAFT_TOKENS;
        int local_token_id = token_id % MAX_DRAFT_TOKENS;
        if (token_id / MAX_DRAFT_TOKENS >= bsz) {
            msg_sed.mtext[i] = 0;
        } else {
            msg_sed.mtext[i] =
                accept_tokens_data[bid * max_draft_tokens + local_token_id];
        }
    }
    if ((msgsnd(msgid,
                &msg_sed,
                (MAX_BSZ * MAX_DRAFT_TOKENS + MAX_BSZ + 2) * 4,
                0)) == -1) {
        printf("full msg buffer\n");
    }
    return;
}

void SpeculateSaveWithOutputMsgStatic(const paddle::Tensor& accept_tokens,
                                      const paddle::Tensor& accept_num,
                                      const paddle::Tensor& not_need_stop,
                                      int64_t rank_id,
                                      bool save_each_rank) {
    SpeculateSaveWithOutputMsg(
        accept_tokens, accept_num, not_need_stop, rank_id, 1, save_each_rank);
}

void SpeculateSaveWithOutputMsgDynamic(const paddle::Tensor& accept_tokens,
                                       const paddle::Tensor& accept_num,
                                       const paddle::Tensor& not_need_stop,
                                       int64_t rank_id,
                                       int msg_queue_id,
                                       bool save_each_rank) {
    SpeculateSaveWithOutputMsg(
        accept_tokens, accept_num, not_need_stop, rank_id, msg_queue_id, save_each_rank);
}

PD_BUILD_STATIC_OP(speculate_save_output)
    .Inputs({"accept_tokens", "accept_num", "not_need_stop"})
    .Attrs({"rank_id: int64_t", "save_each_rank: bool"})
    .Outputs({"x_out"})
    .SetInplaceMap({{"accept_tokens", "x_out"}})
    .SetKernelFn(PD_KERNEL(SpeculateSaveWithOutputMsgStatic));

PD_BUILD_STATIC_OP(speculate_save_output_dynamic)
    .Inputs({"accept_tokens", "accept_num", "not_need_stop"})
    .Attrs({"rank_id: int64_t", "msg_queue_id: int", "save_each_rank: bool"})
    .Outputs({"x_out"})
    .SetInplaceMap({{"accept_tokens", "x_out"}})
    .SetKernelFn(PD_KERNEL(SpeculateSaveWithOutputMsgDynamic));
