use crate::api_tokens::{Token, TokenID, TokenVerb};

use crate::api_tokens;
use crate::utils::time_utils::time;
use actix_remote_ip::RemoteIP;
use actix_web::dev::Payload;
use actix_web::error::{ErrorBadRequest, ErrorUnauthorized};
use actix_web::{Error, FromRequest, HttpRequest};
use std::future::Future;
use std::pin::Pin;

#[derive(serde::Serialize, serde::Deserialize, Debug)]
pub struct TokenClaims {
    pub sub: String,
    pub iat: usize,
    pub exp: usize,
    pub verb: TokenVerb,
    pub path: String,
    pub nonce: String,
}

pub struct ApiAuthExtractor {
    pub token: Token,
    pub claims: TokenClaims,
}

impl FromRequest for ApiAuthExtractor {
    type Error = Error;
    type Future = Pin<Box<dyn Future<Output = Result<Self, Self::Error>>>>;

    fn from_request(req: &HttpRequest, payload: &mut Payload) -> Self::Future {
        let req = req.clone();

        let remote_ip = match RemoteIP::from_request(&req, payload).into_inner() {
            Ok(ip) => ip,
            Err(e) => return Box::pin(async { Err(e) }),
        };

        Box::pin(async move {
            let (token_id, token_jwt) = match (
                req.headers().get("x-token-id"),
                req.headers().get("x-token-content"),
            ) {
                (Some(id), Some(jwt)) => (
                    id.to_str().unwrap_or("").to_string(),
                    jwt.to_str().unwrap_or("").to_string(),
                ),
                (_, _) => {
                    return Err(ErrorBadRequest("API auth headers were not all specified!"));
                }
            };

            let token_id = match TokenID::parse(&token_id) {
                Ok(t) => t,
                Err(e) => {
                    log::error!("Failed to parse token id! {e}");
                    return Err(ErrorBadRequest("Unable to validate token ID!"));
                }
            };

            let token = match api_tokens::get_single(token_id).await {
                Ok(t) => t,
                Err(e) => {
                    log::error!("Failed to retrieve token: {e}");
                    return Err(ErrorBadRequest("Unable to validate token!"));
                }
            };

            if token.is_expired() {
                log::error!("Token has expired (not been used for too long)!");
                return Err(ErrorBadRequest("Unable to validate token!"));
            }

            let claims = match token
                .pub_key
                .as_ref()
                .expect("All tokens shall have public key!")
                .validate_jwt::<TokenClaims>(&token_jwt)
            {
                Ok(c) => c,
                Err(e) => {
                    log::error!("Failed to validate JWT: {e}");
                    return Err(ErrorBadRequest("Unable to validate token!"));
                }
            };

            if claims.sub != token.id.0.to_string() {
                log::error!("JWT sub mismatch (should equal to token id)!");
                return Err(ErrorBadRequest(
                    "JWT sub mismatch (should equal to token id)!",
                ));
            }

            if time() + 60 * 15 < claims.iat as u64 {
                log::error!("iat is in the future!");
                return Err(ErrorBadRequest("iat is in the future!"));
            }

            if claims.exp < claims.iat {
                log::error!("exp shall not be smaller than iat!");
                return Err(ErrorBadRequest("exp shall not be smaller than iat!"));
            }

            if claims.exp - claims.iat > 1800 {
                log::error!("JWT shall not be valid more than 30 minutes!");
                return Err(ErrorBadRequest(
                    "JWT shall not be valid more than 30 minutes!",
                ));
            }

            if claims.path != req.path() {
                log::error!("JWT path mismatch!");
                return Err(ErrorBadRequest("JWT path mismatch!"));
            }

            if claims.verb.as_method() != req.method() {
                log::error!("JWT method mismatch!");
                return Err(ErrorBadRequest("JWT method mismatch!"));
            }

            if !token.rights.contains(claims.verb, req.path()) {
                log::error!(
                    "Attempt to use a token for an unauthorized route! (token_id={})",
                    token.id.0
                );
                return Err(ErrorUnauthorized(
                    "Token cannot be used to query this route!",
                ));
            }

            if let Some(ip) = token.ip_restriction {
                if !ip.contains(remote_ip.0) {
                    log::error!(
                        "Attempt to use a token for an unauthorized IP! {remote_ip:?} token_id={}",
                        token.id.0
                    );
                    return Err(ErrorUnauthorized("Token cannot be used from this IP!"));
                }
            }

            if token.should_update_last_activity() {
                if let Err(e) = api_tokens::refresh_last_used(token.id).await {
                    log::error!("Could not update token last activity! {e}");
                    return Err(ErrorBadRequest("Couldn't refresh token last activity!"));
                }
            }

            Ok(ApiAuthExtractor { token, claims })
        })
    }
}