#include "head.h"

#define int8_t         char
#define uint8_t        unsigned char
#define int32_t        int
#define uint32_t       unsigned int
#define int16_t        short
#define uint16_t       unsigned short


void hb_hex2ascii(uint8_t *hex, char *str, uint32_t len)
{
    uint8_t value = 0;
    uint32_t i;
    int lower = 1;
 
    if (str != NULL) {
 
        for (i = 0; i < len; i++) {
            if (lower == 1) {
                value = 0;
                value |= (*hex & 0xF0) >> 4;
                value |= (*hex & 0x0F) << 4;
                hex++;
                lower = 0;
            } else {
                value = (value >> 4) & 0x0F;
                lower = 1;
            }
 
            if ((value & 0x0F) <= 9) {
                *str++ = '0' + (value & 0x0F);
            } else {
                *str++ = 'a' + (value & 0x0F) - 10;
            }
        }
    }
}




// 小文件的接收
void recvMinFile(int sockfd, int fd, train_t train){
    printf("小文件接收\n");
    while(1){
        bzero(&train, sizeof(train));
        // 接收数据的长度
        recvn(sockfd, &train.length, sizeof(train.length));
        if(train.length == 0){
            break;
        }
        // 接收内容
        recvn(sockfd, train.data, train.length);
        write(fd, train.data, train.length);
    }
}


// 大文件的接收, mmap方式
void recvMaxFile(int sockfd, int fd, off_t filesize){
    printf("大文件接收\n");
    ftruncate(fd, filesize);
    char *p = (char *)mmap(NULL, filesize, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
    ERROR_CHECK(p, MAP_FAILED, "mmap");
    recvn(sockfd, p, filesize);
    munmap(p, filesize);
}


// 续传的接收
void recvAgain(int sockfd, int fd, off_t filesize, off_t offset){
    printf("续传接收\n");
    ftruncate(fd, filesize);
    char *p = (char *)mmap(NULL, filesize, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
    ERROR_CHECK(p, MAP_FAILED, "mmap");
    recvn(sockfd, p+offset, filesize-offset);
    munmap(p, filesize);
}



int recvFile(int sockfd, unsigned char *MD5, MYSQL* mysql, userProcess_t* usr){
    train_t train1, train2, train3, train4;

    // step1：接收文件名长度和文件名
    bzero(&train1,sizeof(train1));
    recvn(sockfd, &train1.length, sizeof(train1.length));
    recvn(sockfd, train1.data, train1.length);
    if(train1.length == 0){
        recvn(sockfd, &train1.length, sizeof(train1.length));
        recvn(sockfd, train1.data, train1.length);
    }
    // 打开文件，若不存在则新建文件
    char newPath[33] = {0};
    //memcpy(newPath,MD5,16);
    for(int i=0; i<16; i++){
        printf("%02x",MD5[i]);
    }
    printf("\n");
    
    hb_hex2ascii(MD5, newPath, 32);
    newPath[32]='\0';
    
    printf("newPath = %s\n", newPath);
    int fd = open(newPath, O_RDWR|O_CREAT, 0666);
    ERROR_CHECK(fd, -1, "open");

    // step2：接收文件总大小
    bzero(&train2,sizeof(train2));
    off_t fileSize;
    recvn(sockfd, &train2.length, sizeof(train2.length));
    recvn(sockfd, train2.data, train2.length);
    memcpy(&fileSize, train2.data, sizeof(off_t));

    // step3：发送initSize，对于文件的发送方相当于偏移量
    bzero(&train3, sizeof(train3));
    struct stat statbuf;
    fstat(fd, &statbuf);
    off_t initSize = statbuf.st_size;
    printf("offset = %ld\n", initSize);
    train3.length = sizeof(statbuf.st_size);
    memcpy(train3.data, &statbuf.st_size, train3.length);
    send(sockfd, &train3, sizeof(train3.length)+train3.length, MSG_NOSIGNAL);


    if(initSize > 0){
        // 续传的接收
        recvAgain(sockfd, fd, fileSize, initSize);
    }
    else if(initSize == 0 && fileSize >= 100*1024*1024){
        // 大文件接收
        recvMaxFile(sockfd, fd, fileSize);
    }
    else if(initSize == 0 && fileSize < 100*1024*1024){
        // 小文件接收
        recvMinFile(sockfd, fd, train4);
    }
    printf("recv file done!\n");


    // 接收完文件内容后lseek到开头
    lseek(fd, 0, SEEK_SET);


    // 非秒传模式，接收完文件后再计算接收方自己的md5码
    MD5_CTX ctx;
    MD5_Init(&ctx);
    char buf[4096];
    while(1){
        bzero(buf, sizeof(buf));
        ssize_t  sret = read(fd, buf, sizeof(buf));
        if(sret == 0){
            break;
        }
        MD5_Update(&ctx, buf, sret);
    }
    unsigned char mdFromRecver[16];   // 将要保存md5码16个字节的二进
    MD5_Final(mdFromRecver, &ctx);

    
    // 写入文件表
    int insRet = insertSql(train1.data, mysql, usr, newPath);
    if(insRet == 0){
        LOGRECORD(INFO,"insertSql success ");
    }else{
        LOGRECORD(INFO,"insertSql faild ! ");
    }
    LOGRECORD(INFO,"recvFile finish");

    printf("此接收文件无错误\n");
    return 0;
}