use core::fmt::Display;
use std::{io::Write, path::PathBuf};

use thiserror::Error;
use werewolves_proto::game::Game;

pub trait Saver: Clone + Send + 'static {
    type Error: Display;

    fn save(&mut self, game: &Game) -> Result<String, Self::Error>;
}

#[derive(Debug, Error)]
pub enum FileSaverError {
    #[error("io error: {0}")]
    IoError(std::io::Error),
    #[error("serialization error: {0}")]
    SerializationError(#[from] ron::Error),
}

impl From<std::io::Error> for FileSaverError {
    fn from(value: std::io::Error) -> Self {
        Self::IoError(value)
    }
}

#[derive(Debug, Clone)]
pub struct FileSaver {
    path: PathBuf,
}

impl FileSaver {
    pub const fn new(path: PathBuf) -> Self {
        Self { path }
    }
}

impl Saver for FileSaver {
    type Error = FileSaverError;

    fn save(&mut self, game: &Game) -> Result<String, Self::Error> {
        let name = format!("werewolves_{}.ron", chrono::Utc::now().timestamp());
        let path = self.path.join(name.clone());
        let mut file = std::fs::File::create_new(path.clone())?;
        // serde_json::to_writer_pretty(&mut file, &game)?;
        ron::ser::to_writer_pretty(&mut file, &game.story(), ron::ser::PrettyConfig::new())?;
        file.flush()?;
        Ok(path.to_str().map(|s| s.to_string()).unwrap_or(name))
    }
}