use std::fmt;

use axum::{http::StatusCode, response::IntoResponse};

use crate::{db, ErrorExt};

pub type AppResult<T> = Result<T, AppError>;

#[derive(Debug)]
pub enum AppError {
    Db(db::DbError),
    IO(std::io::Error),
    Other(Box<dyn std::error::Error + 'static + Send + Sync>),
    BadRequest,
    Unauthorized,
    NotFound,
}

impl fmt::Display for AppError {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        match self {
            Self::Db(_) => write!(f, "database error"),
            Self::IO(_) => write!(f, "io error"),
            Self::Other(_) => write!(f, "other error"),
            Self::BadRequest => write!(f, "bad request"),
            Self::Unauthorized => write!(f, "unauthorized"),
            Self::NotFound => write!(f, "not found"),
        }
    }
}

impl std::error::Error for AppError {
    fn source(&self) -> Option<&(dyn std::error::Error + 'static)> {
        match self {
            Self::Db(err) => Some(err),
            Self::IO(err) => Some(err),
            Self::Other(err) => Some(err.as_ref()),
            Self::NotFound | Self::Unauthorized | Self::BadRequest => None,
        }
    }
}

impl From<db::DbError> for AppError {
    fn from(value: db::DbError) -> Self {
        Self::Db(value)
    }
}

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

impl IntoResponse for AppError {
    fn into_response(self) -> axum::response::Response {
        match self {
            Self::NotFound => StatusCode::NOT_FOUND.into_response(),
            Self::Unauthorized => StatusCode::UNAUTHORIZED.into_response(),
            Self::BadRequest => StatusCode::BAD_REQUEST.into_response(),
            _ => {
                tracing::error!("{}", self.stack());

                StatusCode::INTERNAL_SERVER_ERROR.into_response()
            }
        }
    }
}