use std::env;
use std::path::Path;

use casual::{repl, sexpr_parse_file};

fn usage() {
    println!("usage:\tcasual [-h] [-v] [--no-repl] [<files>]");
    println!("");
    println!("Files will be loaded in order, then drop to REPL (unless \"--no-repl\" is passed).");
    println!(
        "Verbose flag (\"-v\") will result in lexed tokens and parsed AST \
        being dumped to stdout (when on REPL)."
    );
}

fn main() {
    let mut verbose: bool = false;
    let mut no_repl: bool = false;

    let mut file_list = Vec::<String>::new();

    for arg in env::args().skip(1) {
        match &*arg {
            "-v" | "--verbose" => {
                verbose = true;
            }
            "--no-repl" => {
                no_repl = true;
            }
            "-h" | "--help" => {
                usage();
                return;
            }
            _ if arg.starts_with("-") => {
                println!("Unknown option: {}", arg);
                println!("");
                usage();
                return;
            }
            _ => {
                file_list.push(arg.clone());
            }
        }
    }

    for fname in file_list {
        let fpath = Path::new(&fname);
        if !fpath.is_file() {
            println!("File not found (or not file): {}", fname);
            return;
        }
        println!("Loading {}...", fname);
        match sexpr_parse_file(&fpath) {
            Err(e) => {
                println!("Error loading file: {}\n    {}", fname, e);
                return;
            }
            Ok(_) => (),
        }
    }

    if !no_repl {
        repl(verbose);
    }
}