use std::fmt;

use redis::RedisError;

#[derive(Debug)]
pub enum CacheError {
    Serialization(String),
    Backend(RedisError),
}

impl fmt::Display for CacheError {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        match self {
            CacheError::Serialization(msg) => write!(f, "cache serialization error: {msg}"),
            CacheError::Backend(err) => write!(f, "cache backend error: {err}"),
        }
    }
}

impl std::error::Error for CacheError {
    fn source(&self) -> Option<&(dyn std::error::Error + 'static)> {
        match self {
            CacheError::Backend(err) => Some(err),
            _ => None,
        }
    }
}

impl From<RedisError> for CacheError {
    fn from(err: RedisError) -> Self {
        CacheError::Backend(err)
    }
}

impl From<serde_json::Error> for CacheError {
    fn from(err: serde_json::Error) -> Self {
        CacheError::Serialization(err.to_string())
    }
}