use std::{io::ErrorKind, time::Instant};

use serde::{Deserialize, Serialize};
use tokio::{fs::File, io::AsyncWriteExt};

use crate::Error;

#[derive(Deserialize, Serialize, Debug)]
pub struct Metadata {
    pub subject: String,
    pub nonce: String,
    pub etag: Option<String>,
    pub size: Option<u64>,
    pub content_type: Option<String>,
    pub expires_at: u64, // seconds since UNIX_EPOCH
}

impl Metadata {
    pub async fn from_file(path: &str) -> Result<Self, Error> {
        let metadata = match tokio::fs::read_to_string(path).await {
            Ok(x) => Ok(x),
            Err(err) if err.kind() == ErrorKind::NotFound => Err(Error::BinNotFound),
            Err(x) => Err(x.into()),
        }?;
        Ok(toml::from_str::<Self>(&metadata)?)
    }
    pub async fn to_file(&self, path: &str) -> Result<(), Error> {
        let data = toml::to_string(&self)?;
        let mut file = File::create(path).await?;
        file.write_all(data.as_ref()).await?;
        Ok(())
    }
}