#include <stdio.h>
#include <string.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <errno.h>

#include "common.h"

int server(int fd_read, int fd_write);

int main()
{
    FAIL_ON(mknod(FIFO_SERVER_PATH, S_IFIFO | 0666, 0) < 0);
    printf("created %s\n", FIFO_SERVER_PATH);
    FAIL_ON(mknod(FIFO_CLIENT_PATH, S_IFIFO | 0666, 0) < 0);
    printf("created %s\n", FIFO_CLIENT_PATH);

    int read_fd, write_fd;
    FAIL_ON((read_fd=open(FIFO_SERVER_PATH, O_RDONLY)) < 0);
    FAIL_ON((write_fd=open(FIFO_CLIENT_PATH, O_WRONLY)) < 0);

    return server(read_fd, write_fd);
}

#define BUF_SIZE 256

/**
 * Performs server actions
 *
 * @fd_read - pipe to read from
 * @fd_write - pipe to write to
 *
 * returns 0 on success or -errno on fail
 */
int server(int fd_read, int fd_write)
{
    char buf[BUF_SIZE] = {0};
    size_t n = read(fd_read, buf, BUF_SIZE);
    if (n == 0) return -EFAULT;
    FILE *f = fopen(buf, "r");
    // не 100% правильно, но наиболее вероятно
    if (f == NULL) {
        const char error_msg[] = "Can't open requested file\n";
        struct custom_ds payload = {
            .hdr.len = sizeof(error_msg),
            .hdr.type = DS_FAIL,
        };
        strncpy(payload.msg, error_msg, sizeof(error_msg));
        send_msg(fd_write, &payload);
        goto epilog;
    }

    while ((n = fread(buf, sizeof(buf[0]), BUF_SIZE, f)) > 0) {
        struct custom_ds payload = {
            .hdr.len = n,
            .hdr.type = DS_MESSAGE,
        };
        strncpy(payload.msg, buf, n);
        send_msg(fd_write, &payload);
        memset(buf, 0, sizeof(buf));
    }

epilog:
    fclose(f);
    return 0;
}