/*
Description: 标记bam文件中的冗余信息

Copyright : All right reserved by ICT

Author : Zhang Zhonghai
Date : 2023/10/23
*/
#include "markdups_arg.h"

#include <common/utils/global_arg.h>
#include <common/utils/thpool.h>
#include <common/utils/timer.h>
#include <common/utils/util.h>
#include <common/hts/bam_buf.h>
#include <common/hts/read_ends.h>
#include <common/utils/yarn.h>

#include <htslib/sam.h>
#include "htslib/thread_pool.h"

#include <iostream>
#include <vector>
#include <set>
#include <queue>

using namespace std;

#define BAM_BLOCK_SIZE 2 * 1024 * 1024

/* 前向声明 */
class ThMarkDupArg;
/* 全局本地变量 */
static queue<ThMarkDupArg *> qpThMarkDupArg; // 存放线程变量的队列
static lock *queueFirstLock = new_lock(-1); // 队列的第一个任务是否完成

/* 多线程处理冗余参数结构体 */
struct ThMarkDupArg
{
    vector<BamWrap *> *pvBam;
    int startIdx; // 闭区间
    int endIdx; // 开区间
    long seq; // 当前任务在所有任务的排序
    bool more; // 后面还有任务
    volatile bool finish; // 当前任务有没有处理完
    set<int> sDupIdx; // 冗余read的索引
};
/*
 * 多线程查找和标记冗余函数
 */
void thread_markdups(void *arg)
{
    auto &p = *(ThMarkDupArg *)arg;

    p.sDupIdx.insert(1);
    /* 处理数据 */

    /* 本段数据处理完成，告诉输出线程 */
    possess(queueFirstLock);
    p.finish = true;
    cout << "process: " << p.seq << endl;
    auto front = qpThMarkDupArg.front();
    if (front->finish)
    {
        twist(queueFirstLock, TO, front->seq);
    } else {
        release(queueFirstLock);
    }
}

/*
 * 多线程将结果写入文件，写之前需要合并相邻线程的未处理的结果
 */
void thread_write(void *)
{
    bool more = false;
    long seq = 0;
    possess(queueFirstLock);
    wait_for(queueFirstLock, TO_BE, seq++); // 等待首个任务完成
    auto lastP = qpThMarkDupArg.front(); // 取队首的数据
    qpThMarkDupArg.pop(); // 删除队首
    twist(queueFirstLock, TO, seq);
    more = lastP->more;
    while (more) // 循环处理，将结果写入文件
    {
        possess(queueFirstLock);
        if (qpThMarkDupArg.empty()) // 有可能新任务没来得及添加进队列
        {
            release(queueFirstLock);
            continue;
        }
        wait_for(queueFirstLock, TO_BE, seq); // 等待任务完成
        auto p = qpThMarkDupArg.front();
        if (!p->finish) // 有可能这个任务没有完成，是下边那个twist导致进到这里，因为这一段代码可能运行比较快
        {
            twist(queueFirstLock, TO, -1); // 此时队首任务没完成，-1可以让锁无法进入到这里，避免无效获得锁
            continue;
        }
        qpThMarkDupArg.pop();
        twist(queueFirstLock, TO, seq + 1);

        /* 处理结果数据 */
        cout << "finish: " <<  seq - 1 << endl;

        /* 准备下一轮循环 */
        delete lastP;
        more = p->more;
        lastP = p;
        seq++;
    }

    // 处理最后一个数据
    cout << "finish: " << seq - 1 << endl;
    pthread_exit(0);
}

/*
 * Builds a read ends object that represents a single read.
 */
static void buildReadEnds(BamWrap &bw, int64_t index, ReadEnds *pKey)
{
    auto &k = *pKey;
    auto &bc = bw.b->core;
    k.read1ReferenceIndex = bc.tid;
    k.read1Coordinate = (bc.flag & BAM_FREVERSE) ? bw.GetUnclippedEnd() : bw.GetUnclippedStart();
    k.orientation = (bc.flag & BAM_FREVERSE) ? ReadEnds::R : ReadEnds::F;
    k.read1IndexInFile = index;
}

/*
 * mark duplicate 入口，假定bam是按照比对后的坐标排序的，同一个样本的话不需要考虑barcode的问题
 */
int MarkDuplicates(int argc, char *argv[])
{
    Timer::log_time("程序开始");
    Timer time_all;
    /* 初始化参数 */
    GlobalArg &gArg = GlobalArg::Instance();
    MarkDupsArg mdArg;
    vector<AuxVar> vAuxVar;
    mdArg.parseArgument(argc, argv, &gArg); // 解析命令行参数

    // if (gArg.num_threads > 1) // 多线程处理
    if (false)
    {
        threadpool thpool = thpool_init(gArg.num_threads); // 创建mark dup所需的线程池
        thread *writeth = launch(thread_write, nullptr);   // 启动处理结果的的线程
        for (int i = 0; i < 40; ++i)
        {
            ThMarkDupArg *thArg = new ThMarkDupArg({nullptr, i, i * 10, i, true, false});
            if (i == 39)
                thArg->more = false;
            possess(queueFirstLock);                                 // 加锁
            qpThMarkDupArg.push(thArg);                              // 将新任务需要的参数添加到队列
            release(queueFirstLock);                                 // 解锁
            thpool_add_work(thpool, thread_markdups, (void *)thArg); // 添加新任务
        }

        /* 同步所有线程 */
        thpool_wait(thpool);
        thpool_destroy(thpool);
        join(writeth);
    } else { // 单线程串行处理
        /* 打开输入bam文件 */
        sam_hdr_t *inBamHeader;
        samFile *inBamFp;
        inBamFp = sam_open_format(gArg.in_fn.c_str(), "r", nullptr);
        if (! inBamFp) {
            Error("[%s] load sam/bam file failed.\n", __func__);
            return -1;
        }
        hts_set_opt(inBamFp, HTS_OPT_BLOCK_SIZE, BAM_BLOCK_SIZE);
        inBamHeader = sam_hdr_read(inBamFp);
        htsThreadPool htsPoolRead = {NULL, 0}; // 多线程读取，创建线程池
        htsThreadPool htsPoolWrite = {NULL, 0};
        htsPoolRead.pool = hts_tpool_init(gArg.num_threads);
        htsPoolWrite.pool = hts_tpool_init(gArg.num_threads);
        if (!htsPoolRead.pool || !htsPoolWrite.pool)
        {
            Error("[%d] failed to set up thread pool", __LINE__);
            return -1;
        }
        hts_set_opt(inBamFp, HTS_OPT_THREAD_POOL, &htsPoolRead);

        /* 创建输出文件 */
        samFile *outBamFp;
        htsFormat outFormat = {};
        hts_parse_format(&outFormat, "bam");
        outBamFp = sam_open_format(gArg.out_fn.c_str(), "wb", &outFormat);
        hts_set_opt(outBamFp, HTS_OPT_BLOCK_SIZE, BAM_BLOCK_SIZE);
        hts_set_opt(outBamFp, HTS_OPT_THREAD_POOL, &htsPoolWrite); // 用同样的线程池处理输出文件

        // /* 读取缓存初始化 */
        BamBufType inBamBuf(gArg.use_asyncio);
        inBamBuf.Init(inBamFp, inBamHeader, gArg.max_mem);

        /* 循环读入信息，并处理 */
        while (inBamBuf.ReadStat() >= 0)
        {
            int readNum = inBamBuf.ReadBam();
            cout << readNum << endl;
            // inBamBuf.ClearAll();
            // cout << inBamBuf.Size() << endl;
            inBamBuf.ClearBeforeIdx(inBamBuf.Size());
            // break;
            for (int i = 0; i < inBamBuf.Size(); ++i) {
                if (sam_write1(outBamFp, inBamHeader, inBamBuf[i]->b) < 0)
                {
                    Error("failed writing to \"%s\"", gArg.out_fn.c_str());
                    sam_close(outBamFp);
                    return -1;
                }
            }
            if (readNum == 0)
                break;
        }
        
        // int res = -1;
        // bam1_t *b = bam_init1();
        // size_t num = 0;
        // while ((res = sam_read1(inBamFp, inBamHeader, b)) >= 0)
        // {
        //     ++num;
        // }
        // cout << num << endl;

        /* 为每个read创建ReadEnd信息 */

        /* 标记冗余, 将处理后的结果写入文件 */

        /* 关闭文件，收尾清理 */
        sam_close(outBamFp);
        sam_close(inBamFp);
    }

    // cout << "read ends size: " << sizeof(ReadEnds) << endl;

    cout << "总时间: " << time_all.seconds_elapsed() << endl;
    Timer::log_time("程序结束");
    return 0;
}