use actix::Addr;
use actix_identity::Identity;
use actix_remote_ip::RemoteIP;
use actix_web::{web, HttpRequest, HttpResponse, Responder};
use askama::Template;
use std::sync::Arc;

use crate::actors::bruteforce_actor::BruteForceActor;
use crate::actors::users_actor::{LoginResult, UsersActor};
use crate::actors::{bruteforce_actor, users_actor};
use crate::constants::{APP_NAME, MAX_FAILED_LOGIN_ATTEMPTS, MIN_PASS_LEN};
use crate::controllers::base_controller::{
    build_fatal_error_page, redirect_user, redirect_user_for_login,
};
use crate::data::action_logger::{Action, ActionLogger};
use crate::data::login_redirect::LoginRedirect;
use crate::data::provider::{Provider, ProvidersManager};
use crate::data::session_identity::{SessionIdentity, SessionStatus};
use crate::data::user::User;
use crate::data::webauthn_manager::WebAuthManagerReq;

pub struct BaseLoginPage<'a> {
    pub danger: Option<String>,
    pub success: Option<String>,
    pub page_title: &'static str,
    pub app_name: &'static str,
    pub redirect_uri: &'a LoginRedirect,
}

#[derive(Template)]
#[template(path = "login/login.html")]
struct LoginTemplate<'a> {
    _p: BaseLoginPage<'a>,
    login: String,
    providers: Vec<Provider>,
}

#[derive(Template)]
#[template(path = "login/password_reset.html")]
struct PasswordResetTemplate<'a> {
    _p: BaseLoginPage<'a>,
    min_pass_len: usize,
}

#[derive(Template)]
#[template(path = "login/choose_second_factor.html")]
struct ChooseSecondFactorTemplate<'a> {
    _p: BaseLoginPage<'a>,
    user: &'a User,
}

#[derive(Template)]
#[template(path = "login/otp_input.html")]
struct LoginWithOTPTemplate<'a> {
    _p: BaseLoginPage<'a>,
}

#[derive(Template)]
#[template(path = "login/webauthn_input.html")]
struct LoginWithWebauthnTemplate<'a> {
    _p: BaseLoginPage<'a>,
    opaque_state: String,
    challenge_json: String,
}

#[derive(serde::Deserialize)]
pub struct LoginRequestBody {
    login: String,
    password: String,
}

#[derive(serde::Deserialize)]
pub struct LoginRequestQuery {
    logout: Option<bool>,
    #[serde(default)]
    redirect: LoginRedirect,
}

/// Authenticate user
#[allow(clippy::too_many_arguments)]
pub async fn login_route(
    remote_ip: RemoteIP,
    providers: web::Data<Arc<ProvidersManager>>,
    users: web::Data<Addr<UsersActor>>,
    bruteforce: web::Data<Addr<BruteForceActor>>,
    query: web::Query<LoginRequestQuery>,
    req: Option<web::Form<LoginRequestBody>>,
    id: Option<Identity>,
    http_req: HttpRequest,
    logger: ActionLogger,
) -> impl Responder {
    let mut danger = None;
    let mut success = None;
    let mut login = String::new();

    let failed_attempts = bruteforce
        .send(bruteforce_actor::CountFailedAttempt {
            ip: remote_ip.into(),
        })
        .await
        .unwrap();

    if failed_attempts > MAX_FAILED_LOGIN_ATTEMPTS {
        return HttpResponse::TooManyRequests().body(build_fatal_error_page(
            "Too many failed login attempts, please try again later!",
        ));
    }

    // Check if user session must be closed
    if let Some(true) = query.logout {
        if let Some(id) = id {
            logger.log(Action::Signout);
            id.logout();
        }
        success = Some("Goodbye!".to_string());
    }
    // Check if user is already authenticated
    else if SessionIdentity(id.as_ref()).is_authenticated() {
        return redirect_user(query.redirect.get());
    }
    // Check if the password of the user has to be changed
    else if SessionIdentity(id.as_ref()).need_new_password() {
        return redirect_user(&format!(
            "/reset_password?redirect={}",
            query.redirect.get_encoded()
        ));
    }
    // Check if the user has to validate a second factor
    else if SessionIdentity(id.as_ref()).need_2fa_auth() {
        return redirect_user(&format!(
            "/2fa_auth?redirect={}",
            query.redirect.get_encoded()
        ));
    }
    // Try to authenticate user
    else if let Some(req) = &req {
        login = req.login.clone();
        let response: LoginResult = users
            .send(users_actor::LocalLoginRequest {
                login: login.clone(),
                password: req.password.clone(),
            })
            .await
            .unwrap();

        match response {
            LoginResult::Success(user) => {
                let status = if user.need_reset_password {
                    logger.log(Action::UserNeedNewPasswordOnLogin(&user));
                    SessionStatus::NeedNewPassword
                } else if user.has_two_factor() && !user.can_bypass_two_factors_for_ip(remote_ip.0)
                {
                    logger.log(Action::UserNeed2FAOnLogin(&user));
                    SessionStatus::Need2FA
                } else {
                    logger.log(Action::UserSuccessfullyAuthenticated(&user));
                    SessionStatus::SignedIn
                };

                SessionIdentity(id.as_ref()).set_user(&http_req, &user, status);
                return redirect_user(query.redirect.get());
            }

            LoginResult::AccountDisabled => {
                log::warn!("Failed login for username {} : account is disabled", &login);
                logger.log(Action::TryLoginWithDisabledAccount(&login));
                danger = Some("Your account is disabled!".to_string());
            }

            LoginResult::LocalAuthForbidden => {
                log::warn!("Failed login for username {} : attempted to use local auth, but it is forbidden", &login);
                logger.log(Action::TryLocalLoginFromUnauthorizedAccount(&login));
                danger = Some("You cannot login from local auth with your account!".to_string());
            }

            LoginResult::Error => {
                danger = Some("An unkown error occured while trying to sign you in!".to_string());
            }

            c => {
                log::warn!(
                    "Failed login for ip {:?} /  username {}: {:?}",
                    remote_ip,
                    login,
                    c
                );
                logger.log(Action::FailedLoginWithBadCredentials(&login));
                danger = Some("Login failed.".to_string());

                bruteforce
                    .send(bruteforce_actor::RecordFailedAttempt {
                        ip: remote_ip.into(),
                    })
                    .await
                    .unwrap();
            }
        }
    }

    HttpResponse::Ok().content_type("text/html").body(
        LoginTemplate {
            _p: BaseLoginPage {
                page_title: "Login",
                danger,
                success,
                app_name: APP_NAME,
                redirect_uri: &query.redirect,
            },
            login,
            providers: providers.cloned(),
        }
        .render()
        .unwrap(),
    )
}

/// Sign out user
pub async fn logout_route() -> impl Responder {
    redirect_user("/login?logout=true")
}

#[derive(serde::Deserialize)]
pub struct ChangePasswordRequestBody {
    password: String,
}

#[derive(serde::Deserialize)]
pub struct PasswordResetQuery {
    #[serde(default)]
    redirect: LoginRedirect,
}

/// Reset user password route
pub async fn reset_password_route(
    id: Option<Identity>,
    query: web::Query<PasswordResetQuery>,
    req: Option<web::Form<ChangePasswordRequestBody>>,
    users: web::Data<Addr<UsersActor>>,
    http_req: HttpRequest,
    logger: ActionLogger,
) -> impl Responder {
    let mut danger = None;

    if !SessionIdentity(id.as_ref()).need_new_password() {
        return redirect_user_for_login(query.redirect.get());
    }

    let user_id = SessionIdentity(id.as_ref()).user_id();

    // Check if user is setting a new  password
    if let Some(req) = &req {
        if req.password.len() < MIN_PASS_LEN {
            danger = Some("Password is too short!".to_string());
        } else {
            let res: bool = users
                .send(users_actor::ChangePasswordRequest {
                    user_id: user_id.clone(),
                    new_password: req.password.clone(),
                    temporary: false,
                })
                .await
                .unwrap();

            if !res {
                danger = Some("Failed to change password!".to_string());
            } else {
                SessionIdentity(id.as_ref()).set_status(&http_req, SessionStatus::SignedIn);
                logger.log(Action::UserChangedPasswordOnLogin(&user_id));
                return redirect_user(query.redirect.get());
            }
        }
    }

    HttpResponse::Ok().content_type("text/html").body(
        PasswordResetTemplate {
            _p: BaseLoginPage {
                page_title: "Password reset",
                danger,
                success: None,
                app_name: APP_NAME,
                redirect_uri: &query.redirect,
            },
            min_pass_len: MIN_PASS_LEN,
        }
        .render()
        .unwrap(),
    )
}

#[derive(serde::Deserialize)]
pub struct ChooseSecondFactorQuery {
    #[serde(default)]
    redirect: LoginRedirect,
    #[serde(default = "bool::default")]
    force_display: bool,
}

/// Let the user select the factor to use to authenticate
pub async fn choose_2fa_method(
    id: Option<Identity>,
    query: web::Query<ChooseSecondFactorQuery>,
    users: web::Data<Addr<UsersActor>>,
) -> impl Responder {
    if !SessionIdentity(id.as_ref()).need_2fa_auth() {
        log::trace!("User does not require 2fa auth, redirecting");
        return redirect_user_for_login(query.redirect.get());
    }

    let user: User = users
        .send(users_actor::GetUserRequest(
            SessionIdentity(id.as_ref()).user_id(),
        ))
        .await
        .unwrap()
        .0
        .expect("Could not find user!");

    // Automatically choose factor if there is only one factor
    if user.get_distinct_factors_types().len() == 1 && !query.force_display {
        log::trace!("User has only one factor, using it by default");
        return redirect_user(&user.two_factor[0].login_url(&query.redirect));
    }

    HttpResponse::Ok().content_type("text/html").body(
        ChooseSecondFactorTemplate {
            _p: BaseLoginPage {
                page_title: "Two factor authentication",
                danger: None,
                success: None,
                app_name: APP_NAME,
                redirect_uri: &query.redirect,
            },
            user: &user,
        }
        .render()
        .unwrap(),
    )
}

#[derive(serde::Deserialize)]
pub struct LoginWithOTPQuery {
    #[serde(default)]
    redirect: LoginRedirect,
}

#[derive(serde::Deserialize)]
pub struct LoginWithOTPForm {
    code: String,
}

/// Login with OTP
pub async fn login_with_otp(
    id: Option<Identity>,
    query: web::Query<LoginWithOTPQuery>,
    form: Option<web::Form<LoginWithOTPForm>>,
    users: web::Data<Addr<UsersActor>>,
    http_req: HttpRequest,
    remote_ip: RemoteIP,
    logger: ActionLogger,
) -> impl Responder {
    let mut danger = None;

    if !SessionIdentity(id.as_ref()).need_2fa_auth() {
        return redirect_user_for_login(query.redirect.get());
    }

    let user: User = users
        .send(users_actor::GetUserRequest(
            SessionIdentity(id.as_ref()).user_id(),
        ))
        .await
        .unwrap()
        .0
        .expect("Could not find user!");

    let keys = user.get_otp_factors();
    if keys.is_empty() {
        return HttpResponse::Ok().body(build_fatal_error_page("Factor not found!"));
    }

    if let Some(form) = form {
        if !keys
            .iter()
            .any(|k| k.check_code(&form.code).unwrap_or(false))
        {
            logger.log(Action::OTPLoginAttempt {
                success: false,
                user: &user,
            });
            danger = Some("Specified code is invalid!".to_string());
        } else {
            users
                .send(users_actor::AddSuccessful2FALogin(
                    user.uid.clone(),
                    remote_ip.0,
                ))
                .await
                .unwrap();

            SessionIdentity(id.as_ref()).set_status(&http_req, SessionStatus::SignedIn);
            logger.log(Action::OTPLoginAttempt {
                success: true,
                user: &user,
            });
            return redirect_user(query.redirect.get());
        }
    }

    HttpResponse::Ok().body(
        LoginWithOTPTemplate {
            _p: BaseLoginPage {
                danger,
                success: None,
                page_title: "Two-Factor Auth",
                app_name: APP_NAME,
                redirect_uri: &query.redirect,
            },
        }
        .render()
        .unwrap(),
    )
}

#[derive(serde::Deserialize)]
pub struct LoginWithWebauthnQuery {
    #[serde(default)]
    redirect: LoginRedirect,
}

/// Login with Webauthn
pub async fn login_with_webauthn(
    id: Option<Identity>,
    query: web::Query<LoginWithWebauthnQuery>,
    manager: WebAuthManagerReq,
    users: web::Data<Addr<UsersActor>>,
) -> impl Responder {
    if !SessionIdentity(id.as_ref()).need_2fa_auth() {
        return redirect_user_for_login(query.redirect.get());
    }

    let user: User = users
        .send(users_actor::GetUserRequest(
            SessionIdentity(id.as_ref()).user_id(),
        ))
        .await
        .unwrap()
        .0
        .expect("Could not find user!");

    let pub_keys = user.get_webauthn_pub_keys();
    if pub_keys.is_empty() {
        return HttpResponse::Ok()
            .body(build_fatal_error_page("No Webauthn public key registered!"));
    }

    let challenge = match manager.start_authentication(&user.uid, &pub_keys) {
        Ok(c) => c,
        Err(e) => {
            log::error!("Failed to generate webauthn challenge! {:?}", e);
            return HttpResponse::InternalServerError().body(build_fatal_error_page(
                "Failed to generate webauthn challenge",
            ));
        }
    };

    let challenge_json = match serde_json::to_string(&challenge.login_challenge) {
        Ok(r) => r,
        Err(e) => {
            log::error!("Failed to serialize challenge! {:?}", e);
            return HttpResponse::InternalServerError().body("Failed to serialize challenge!");
        }
    };

    HttpResponse::Ok().body(
        LoginWithWebauthnTemplate {
            _p: BaseLoginPage {
                danger: None,
                success: None,
                page_title: "Two-Factor Auth",
                app_name: APP_NAME,
                redirect_uri: &query.redirect,
            },
            opaque_state: challenge.opaque_state,
            challenge_json: urlencoding::encode(&challenge_json).to_string(),
        }
        .render()
        .unwrap(),
    )
}