/**
 * @file mount.c
 * @brief Mount a block device as FAT32.
 *
 * Writes to /sys/vfs/mount to trigger a kernel-level FAT32 mount.
 *
 * Usage: mount <device> <path>
 *   e.g.: mount hdd1mbr1 /mnt
 */

#include "syscalls.h"

int main(void) {
    char device[64];
    char path[128];

    if (getenv("ARG1", device, sizeof(device)) < 0 || device[0] == '\0') {
        puts("Usage: mount <device> <mountpoint>\n");
        puts("  e.g.: mount hdd1mbr1 /mnt\n");
        return 1;
    }

    /* ARG1 contains "device path" — we need to split it.
     * Actually, the shell currently only passes the first word as ARG1.
     * Let's accept: mount <device> <path> where ARG1 = "device path" */

    /* Find the space separating device and path */
    int i = 0;
    while (device[i] && device[i] != ' ') i++;

    if (device[i] == ' ') {
        /* ARG1 contains both: "hdd1mbr1 /mnt" */
        device[i] = '\0';
        /* Copy path part */
        int j = i + 1;
        while (device[j] == ' ') j++;
        int pi = 0;
        while (device[j] && pi < 127) {
            path[pi++] = device[j++];
        }
        path[pi] = '\0';
    } else {
        /* Only device, no path — default to /mnt */
        path[0] = '/'; path[1] = 'm'; path[2] = 'n'; path[3] = 't';
        path[4] = '\0';
    }

    if (path[0] == '\0') {
        puts("mount: missing mountpoint, using /mnt\n");
        path[0] = '/'; path[1] = 'm'; path[2] = 'n'; path[3] = 't';
        path[4] = '\0';
    }

    /* Build the mount command: "device path" */
    char cmd[192];
    int pos = 0;
    for (int k = 0; device[k] && pos < 190; k++) cmd[pos++] = device[k];
    cmd[pos++] = ' ';
    for (int k = 0; path[k] && pos < 190; k++) cmd[pos++] = path[k];
    cmd[pos] = '\0';

    /* Open /sys/vfs/mount and write the command */
    int32_t fd = open("/sys/vfs/mount", 0);
    if (fd < 0) {
        puts("mount: cannot open /sys/vfs/mount\n");
        return 1;
    }

    int32_t n = write(fd, cmd, (uint32_t)pos);
    close(fd);

    if (n < 0) {
        /* Read the status to show the error */
        fd = open("/sys/vfs/mounts", 0);
        if (fd >= 0) {
            char status[256];
            int32_t sn = read(fd, status, sizeof(status) - 1);
            close(fd);
            if (sn > 0) {
                status[sn] = '\0';
                puts(status);
            }
        } else {
            puts("mount: failed\n");
        }
        return 1;
    }

    puts("mount: ");
    puts(device);
    puts(" mounted at ");
    puts(path);
    puts("\n");
    return 0;
}