#include <stdio.h>

#include <stdlib.h>

#include <uv.h>

uv_loop_t *loop;

const char *command;

void run_command(uv_fs_event_t *handle, const char *filename, int events, int status) {

    char path[1024];

    size_t size = 1023;

    // Does not handle error if path is longer than 1023.

    uv_fs_event_getpath(handle, path, &size);

    path[size] = '\0';

    fprintf(stderr, "Change detected in %s: ", path);

    if (events & UV_RENAME)

        fprintf(stderr, "renamed");

    if (events & UV_CHANGE)

        fprintf(stderr, "changed");

    fprintf(stderr, " %s\n", filename ? filename : "");

    system(command);

}

int main(int argc, char **argv) {

    if (argc <= 2) {

        fprintf(stderr, "Usage: %s <command> <file1> [file2 ...]\n", argv[0]);

        return 1;

    }

    loop = uv_default_loop();

    command = argv[1];

    while (argc-- > 2) {

        fprintf(stderr, "Adding watch on %s\n", argv[argc]);

        uv_fs_event_t *fs_event_req = malloc(sizeof(uv_fs_event_t));

        uv_fs_event_init(loop, fs_event_req);

        // The recursive flag watches subdirectories too.

        uv_fs_event_start(fs_event_req, run_command, argv[argc], UV_FS_EVENT_RECURSIVE);

    }

    return uv_run(loop, UV_RUN_DEFAULT);

}