use serde::Serialize;
use rocket::http::Status;
use rocket::request::{Request, Outcome};
use rocket::response::{self, Response, Responder};
use rocket_contrib::json::Json;
use crate::models::users::UserError;
use serde_json::Value;


#[derive(Serialize, Debug)]
pub struct ErrorResponse {
    #[serde(with = "StatusDef")]
    #[serde(flatten)]
    pub status: Status,
    pub message: String,
    #[serde(skip_serializing_if = "Option::is_none")]
    pub details: Option<Value>
}

#[derive(Serialize)]
#[serde(remote = "Status")]
struct StatusDef {
    code: u16,
    #[serde(rename = "status")]
    reason: &'static str,
}

impl ErrorResponse {
    pub fn new(status: Status, message: String) -> ErrorResponse {
        ErrorResponse {
            status,
            message,
            details: None,
        }
    }

    pub fn with_details<T: Serialize> (self, details: T) -> ErrorResponse {
        ErrorResponse {
            details: serde_json::to_value(details).ok(),
            ..self
        }
    }

    pub fn err<R>(self) -> Result<R, ErrorResponse> {
        Err(self)
    }
}

impl<'r> Responder<'r, 'static> for ErrorResponse {
    fn respond_to(self, req: &'r Request<'_>) -> response::Result<'static> {
        let status = self.status;
        Response::build_from(Json(self).respond_to(req)?).status(status).ok()
    }
}

impl From<UserError> for ErrorResponse {
    fn from(e: UserError) -> Self {
        match e {
            UserError::NotFound => ErrorResponse::new(Status::Unauthorized, "Provided credentials or token do not match any existing user".into()),
            UserError::UserExists => ErrorResponse::new(Status::Conflict, "User already exists".into()),
            UserError::BadToken => ErrorResponse::new(Status::BadRequest, "Malformed token".into()),
            UserError::ExpiredToken => ErrorResponse::new(Status::Unauthorized, "The provided token has expired".into()),
            UserError::MalformedHeader => ErrorResponse::new(Status::BadRequest, "Malformed authorization header".into()),
            UserError::PermissionDenied => ErrorResponse::new(Status::Forbidden, "Bearer is not authorized to access the resource".into()),
            UserError::ZoneNotFound => ErrorResponse::new(Status::NotFound, "DNS zone does not exists".into()),
            UserError::DbError(e) => make_500(e),
            UserError::PasswordError(e) => make_500(e)
        }
    }
}


impl<S> From<ErrorResponse> for Outcome<S, ErrorResponse> {
    fn from(e: ErrorResponse) -> Self {
        Outcome::Failure(e.into())
    }
}


impl From<ErrorResponse> for (Status, ErrorResponse) {
    fn from(e: ErrorResponse) -> Self {
        (e.status, e)
    }
}

pub fn make_500<E: std::fmt::Debug>(e: E) -> ErrorResponse {
    println!("Making 500 for Error: {:?}", e);
    ErrorResponse::new(Status::InternalServerError, "An unexpected error occured.".into())
}