/*  Mycelium Scheme
 *  Copyright (C) 2025 Ava Affine
 *
 *  This program is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation, either version 3 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */

#![feature(iter_collect_into)]

use mycelium::{lexer as l, parser as p};

use std::rc::Rc;
use std::path::PathBuf;
use std::fs;
use std::error::Error;
use std::time::Instant;

use clap::Parser;

#[derive(Parser, Debug)]
#[command(version, about, long_about = None)]
struct Args {
    /// display time to parse scripts
    #[arg(short, long)]
    time: bool,

    /// output script AST once parsed
    #[arg(short, long)]
    debug: bool,

    scripts: Vec<PathBuf>,
}

fn main() -> Result<(), Box<dyn Error>> {
    let args = Args::parse();
    for script in args.scripts {
        println!("+ processing {:#?}", script);
        let message = fs::read_to_string(script)?;

        let start: Option<Instant>;
        if args.time {
            start = Some(Instant::now());
        } else {
            start = None;
        }

        let mut p = p::Parser::from(l::Lexer::from(Rc::from(message.as_str())));
        let mut i = p.next();
        while let Some(ref r) = i {
            if args.debug {
                println!("  > res: {}", r);
            }

            i = p.next();
        }

        if let Some(i) = start {
            println!("  > time: {:#?}", i.elapsed());
        }

        if p.has_error_state.is_some() {
            let e = p.has_error_state.unwrap();
            if e.0 != l::E_END_OF_DOCUMENT {
                println!("  > error!\n{}", e);
            }
        }
    }


    Ok(())
}