You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: nx.rs
    path of file: ./repos/nixpacks/src/providers/node
    
    the code of the file until where you have to start completion: // Code relating to NX Monorepos

use std::path::PathBuf;

use anyhow::Result;
use serde::{Deserialize, Serialize};
use serde_json::Value;

use crate::nixpacks::{app::A
    
    pub fn get_nx_start_cmd(app: &App, env: &Environment) -> Result<Option<String>> {
        if !Nx::is_nx_monorepo(app, env) {
            return Ok(None);
        }

        if let Some(nx_app_name) = Nx::get_nx_app_name(app, env) {
            let output_path = Nx::get_nx_output_path(app, &nx_app_name)?;
            let project_json = Nx::get_nx_project_json_for_app(app, &nx_app_name)?;

            if let Some(start_target) = project_json.targets.start {
                if let Some(configurations) = start_target.configurations {
                    if configurations.production.is_some() {
                        return Ok(Some(format!(
                            "{} nx run {nx_app_name}:start:production",
                            NodeProvider::get_package_manager_dlx_command(app)
                        )));
                    }
                }
                return Ok(Some(format!(
                    "{} nx run {nx_app_name}:start",
                    NodeProvider::get_package_manager_dlx_command(app)
                )));
            }

            if project_json.targets.build.executor == "@nx/next:build"
                || project_json.targets.build.executor == "@nrwl/next:build"
            {
                return Ok(Some(format!("cd {output_path} && npm run start")));
            }

            if let Some(options) = project_json.targets.build.options {
                if let Some(main_path) = options.main {
                    let current_path = PathBuf::from(main_path);
                    let file_name = current_path.file_stem().unwrap().to_str().unwrap();

                    return Ok(Some(format!("node {output_path}/{file_name}.js")));
                }
            }
            return Ok(Some(format!("node {output_path}/index.js")));
        }

        Ok(None)
    }