use std::fs;use std::io::{self, Read, Write}; use clap::Parser; #[derive(Parser, Debug)]#[command(name = "openapi-extractor-rs")]struct Cli {    #[arg(long)]    source_name: String,    #[arg(long)]    input: String,    #[arg(long)]    output: Option<String>,    #[arg(long, default_value_t = false)]    pretty: bool,} fn main() {    if let Err(error) = run() {        eprintln!("{error}");        std::process::exit(1);    }} fn run() -> Result<(), String> {    let args = Cli::parse();    let source_text = read_input_text(&args.input)?;     let output_json =        openapi_extractor_rs::extract_manifest_json(&args.source_name, &source_text, args.pretty)?;     if let Some(path) = args.output {        fs::write(path, output_json).map_err(|error| format!("write output file: {error}"))?;    } else {        let mut stdout = io::stdout().lock();        stdout            .write_all(output_json.as_bytes())            .map_err(|error| format!("write stdout: {error}"))?;        stdout            .write_all(b"\n")            .map_err(|error| format!("write stdout newline: {error}"))?;    }     Ok(())} fn read_input_text(input: &str) -> Result<String, String> {    if input == "-" {        let mut buffer = String::new();        io::stdin()            .read_to_string(&mut buffer)            .map_err(|error| format!("read stdin: {error}"))?;        return Ok(buffer);    }     fs::read_to_string(input).map_err(|error| format!("read input file '{input}': {error}"))}