use anyhow::{bail, Result};
use crossterm::style::Stylize;
use std::io::{self, Write};

use crate::app_state::{AppState, ExercisesProgress};

pub fn run(app_state: &mut AppState) -> Result<()> {
    let exercise = app_state.current_exercise();
    let output = exercise.run()?;

    let mut stdout = io::stdout().lock();
    stdout.write_all(&output.stdout)?;
    stdout.write_all(b"\n")?;
    stdout.write_all(&output.stderr)?;
    stdout.flush()?;

    if !output.status.success() {
        app_state.set_pending(app_state.current_exercise_ind())?;

        bail!("Ran {exercise} with errors");
    }

    stdout.write_fmt(format_args!(
        "{}{}\n",
        "✓ Successfully ran ".green(),
        exercise.path.to_string_lossy().green(),
    ))?;

    match app_state.done_current_exercise(&mut stdout)? {
        ExercisesProgress::AllDone => (),
        ExercisesProgress::Pending => println!("Next exercise: {}", app_state.current_exercise()),
    }

    Ok(())
}