use axum::{
    http::StatusCode,
    response::{IntoResponse, Response},
    Json,
};
use serde::Serialize;

#[derive(Debug, thiserror::Error)]
pub enum AppError {
    #[error("bad request: {0}")]
    BadRequest(String),
    #[error("provider unavailable: {0}")]
    ProviderUnavailable(String),
    #[error("internal error: {0}")]
    Internal(String),
    #[error("external service error: {0}")]
    ExternalService(String),
}

#[derive(Debug, Serialize)]
struct ErrorBody {
    error: String,
}

impl IntoResponse for AppError {
    fn into_response(self) -> Response {
        let status = match self {
            AppError::BadRequest(_) => StatusCode::BAD_REQUEST,
            AppError::ProviderUnavailable(_) => StatusCode::SERVICE_UNAVAILABLE,
            AppError::Internal(_) => StatusCode::INTERNAL_SERVER_ERROR,
            AppError::ExternalService(_) => StatusCode::BAD_GATEWAY,
        };

        let body = Json(ErrorBody {
            error: self.to_string(),
        });

        (status, body).into_response()
    }
}

impl From<sqlx::Error> for AppError {
    fn from(value: sqlx::Error) -> Self {
        AppError::Internal(value.to_string())
    }
}