//! Videl configuration
use std::{
    path::{
	PathBuf,
    },
    error,
    fmt,
    io
};
use tokio::fs;

#[derive(Debug, Clone, PartialEq, Eq, Hash)]
pub struct Config
{
    pub base_dir: PathBuf,
}

impl Default for Config
{
    #[inline]
    fn default() -> Self
    {
	Self {
	    base_dir: PathBuf::from("/tmp/videl"),
	}
    }
}

impl Config
{
    /// Validate this config
    pub async fn validate(&self) -> Result<(), Error>
    {
	let exists = self.base_dir.exists();
	if exists && !self.base_dir.is_dir() {
	    return Err(Error::InvalidDestination);
	} else if !exists {
	    fs::create_dir_all(&self.base_dir).await?;
	}
	Ok(())
    }
}

#[derive(Debug)]
pub enum Error {
    IO(io::Error),
    InvalidDestination,
}
impl error::Error for Error
{
    fn source(&self) -> Option<&(dyn error::Error + 'static)> {
	match &self {
	    Self::IO(io) => Some(io),
	    _ => None,
	}
    }
}
impl fmt::Display for Error
{
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result
    {
	match self {
	    Self::IO(_) => write!(f, "i/o error"),
	    Self::InvalidDestination => write!(f, "invalid base destination for videl databases"),
	}
    }
}

impl From<io::Error> for Error
{
    #[inline] fn from(from: io::Error) -> Self
    {
	Self::IO(from)
    }
}