/* Copyright 2021 Dominik George <dominik.george@teckids.org>
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

use crate::config::{
    get_config,
    get_optional,
    get_or_error
};
use config::Config;
use crate::cache::get_cache;

use crate::logging::setup_log;

use crate::oauth::get_data;
use std::collections::HashMap;
use serde_json::value::Value;

use libc::{getpwuid, geteuid};
use std::ffi::CStr;

use libnss::interop::Response;
use libnss::passwd::{PasswdHooks, Passwd};

fn nss_hook_prepare() -> Config {
    let conf = get_config(None);

    let mut log_level = log::LevelFilter::Error;
    if get_optional(&conf, "nss.debug").unwrap_or_default() {
        log_level = log::LevelFilter::Debug;
    }
    setup_log(log_level);

    return conf;
}

fn get_current_user() -> String {
    let euid;
    let euser;
    unsafe {
        euid = geteuid();
        euser = CStr::from_ptr((*getpwuid(euid)).pw_name);
    };
    euser.to_str().ok().unwrap().to_string()
}

struct OidcPasswd;

impl PasswdHooks for OidcPasswd {
    fn get_all_entries() -> Response<Vec<Passwd>> {
        let conf = nss_hook_prepare();
        let mut cache = get_cache();

        let user = get_current_user();
        let token = match cache.load_user_token(&user) {
            Some(t) => t,
            None => return Response::Unavail
        };

        let data: Vec<HashMap<String, Value>> = match get_data(conf, "nss", "passwd", token, "") {
            Ok(d) => d,
            Err(_) => return Response::Unavail
        };
        for ent in &data {
            for (k, v) in ent {
                debug!("{} {}", k, v);
            }
        }

        Response::Success(
            vec![
                Passwd {
                    name: "test".to_string(),
                    passwd: "x".to_string(),
                    uid: 1005,
                    gid: 1005,
                    gecos: "Test Account".to_string(),
                    dir: "/home/test".to_string(),
                    shell: "/bin/bash".to_string(),
                }
            ]
        )
    }

    fn get_entry_by_uid(uid: libc::uid_t) -> Response<Passwd> {
        if uid == 1005 {
            return Response::Success(Passwd {
                name: "test".to_string(),
                passwd: "x".to_string(),
                uid: 1005,
                gid: 1005,
                gecos: "Test Account".to_string(),
                dir: "/home/test".to_string(),
                shell: "/bin/bash".to_string(),
            });
        }

        Response::NotFound
    }

    fn get_entry_by_name(name: String) -> Response<Passwd> {
        if name == "test" {
            return Response::Success(Passwd {
                name: "test".to_string(),
                passwd: "x".to_string(),
                uid: 1005,
                gid: 1005,
                gecos: "Test Account".to_string(),
                dir: "/home/test".to_string(),
                shell: "/bin/bash".to_string(),
            });
        }

        Response::NotFound
    }
}

libnss_passwd_hooks!(oidc, OidcPasswd);