#include "test_utils.h"

static int test_single_file_random_perf(const char *path)
{
    size_t io_size = 128 * 1024;
    size_t max_size = 2ULL * 1024 * 1024 * 1024;
    size_t max_count = max_size / io_size;
    int test_sec = 10;
    int direct = 0;

    printf("\n=== test_single_file_random_perf ===\n");
    printf("Path    : %s\n", path);
    printf("IO size : %zu KB\n", io_size / 1024);
    printf("Range   : %zu MB\n", max_size / 1024 / 1024);
    printf("Duration: %d sec\n", test_sec);

    srand(0x1234);

    char *buf = aligned_alloc(4096, io_size);
    if (!buf) { perror("aligned_alloc"); return 1; }
    memset(buf, 'A', io_size);

    struct timespec t1, t2, now;

    unlink(path);

    int fd = open(path, O_CREAT | O_RDWR | direct, 0644);
    if (fd < 0) { perror("open rand write"); free(buf); return 2; }

    clock_gettime(CLOCK_MONOTONIC, &t1);

    size_t wcount = 0;
    do {
        size_t blk = rand() % max_count;
        off_t offset = (off_t)blk * io_size;

        if (lseek(fd, offset, SEEK_SET) < 0) {
            perror("lseek rand write");
            close(fd);
            free(buf);
            return 3;
        }

        if (write(fd, buf, io_size) != (ssize_t)io_size) {
            perror("rand write");
            close(fd);
            free(buf);
            return 4;
        }

        wcount++;
        clock_gettime(CLOCK_MONOTONIC, &now);
    } while (time_diff_sec(t1, now) < test_sec);

    clock_gettime(CLOCK_MONOTONIC, &t2);
    close(fd);

    double wsec = time_diff_sec(t1, t2);
    double wmb = (double)wcount * io_size / 1024 / 1024;

    printf("\nRANDOM WRITE:\n");
    printf("  total : %.1f MB\n", wmb);
    printf("  time  : %.3f sec\n", wsec);
    printf("  IOPS  : %.0f ops/sec\n", wcount / wsec);
    printf("  BW    : %.2f MB/s\n", wmb / wsec);

    fd = open(path, O_RDONLY | direct);
    if (fd < 0) { perror("open rand read"); free(buf); return 5; }

    clock_gettime(CLOCK_MONOTONIC, &t1);

    size_t rcount = 0;
    do {
        size_t blk = rand() % max_count;
        off_t offset = (off_t)blk * io_size;

        if (lseek(fd, offset, SEEK_SET) < 0) {
            perror("lseek rand read");
            close(fd);
            free(buf);
            return 6;
        }

        ssize_t r = read(fd, buf, io_size);
        if (r < 0) {
            perror("rand read");
            close(fd);
            free(buf);
            return 7;
        }

        rcount++;
        clock_gettime(CLOCK_MONOTONIC, &now);
    } while (time_diff_sec(t1, now) < test_sec);

    clock_gettime(CLOCK_MONOTONIC, &t2);
    close(fd);

    double rsec = time_diff_sec(t1, t2);
    double rmb = (double)rcount * io_size / 1024 / 1024;

    printf("\nRANDOM READ:\n");
    printf("  total : %.1f MB\n", rmb);
    printf("  time  : %.3f sec\n", rsec);
    printf("  IOPS  : %.0f ops/sec\n", rcount / rsec);
    printf("  BW    : %.2f MB/s\n", rmb / rsec);

    unlink(path);
    free(buf);
    return 0;
}

int main(int argc, char **argv)
{
    char path[PATH_MAX];
    make_path(path, sizeof(path), argc >= 2 ? argv[1] : NULL, "file.dat");
    int rc = test_single_file_random_perf(path);
    return report_result("test_single_file_random_perf", rc);
}