// Copyright 2024 RustFS Team
//
// 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::error::{Error, Result, is_err_config_not_found};
use crate::is_iam_first_cluster_node_local;
use crate::sys::{get_claims_from_token_with_secret, get_claims_from_token_with_secret_allow_missing_exp};
use crate::{
    cache::{Cache, CacheEntity, LockedCache},
    error::{Error as IamError, is_err_no_such_group, is_err_no_such_policy, is_err_no_such_user},
    store::{GroupInfo, MappedPolicy, Store, UserType, object::IAM_CONFIG_PREFIX},
    sys::{
        MAX_SVCSESSION_POLICY_SIZE, SESSION_POLICY_NAME, SESSION_POLICY_NAME_EXTRACTED, SITE_REPLICATOR_CLAIM,
        SITE_REPLICATOR_SERVICE_ACCOUNT, STATUS_DISABLED, STATUS_ENABLED, UpdateServiceAccountOpts,
    },
};
use futures::future::join_all;
use rustfs_credentials::{Credentials, EMBEDDED_POLICY_TYPE, INHERITED_POLICY_TYPE};
use rustfs_madmin::{AccountStatus, AddOrUpdateUserReq, GroupDesc};
use rustfs_policy::{
    arn::ARN,
    auth::{self, UserIdentity, is_secret_key_valid, jwt_sign},
    format::Format,
    policy::{Policy, PolicyDoc, default::DEFAULT_POLICIES, iam_policy_claim_name_sa},
};
use rustfs_utils::{get_env_opt_str, path::path_join_buf};
use serde::{Deserialize, Serialize};
use serde_json::Value;
use std::sync::atomic::{AtomicU8, AtomicU64};
use std::{
    collections::{HashMap, HashSet},
    sync::{
        Arc,
        atomic::{AtomicBool, AtomicI64, Ordering},
    },
    time::Duration,
};
use time::OffsetDateTime;
use tokio::{
    select,
    sync::{
        mpsc,
        mpsc::{Receiver, Sender},
    },
};
use tracing::warn;
use tracing::{debug, error};

const IAM_FORMAT_FILE: &str = "format.json";
const IAM_FORMAT_VERSION_1: i32 = 1;
#[cfg(not(test))]
const INITIAL_LOAD_RETRY_DELAY: Duration = Duration::from_secs(1);
#[cfg(test)]
const INITIAL_LOAD_RETRY_DELAY: Duration = Duration::from_millis(1);
#[cfg(not(test))]
const TEMP_USER_PERSISTENCE_VERIFY_RETRY_DELAY: Duration = Duration::from_millis(200);
#[cfg(test)]
const TEMP_USER_PERSISTENCE_VERIFY_RETRY_DELAY: Duration = Duration::from_millis(1);
const TEMP_USER_PERSISTENCE_VERIFY_MAX_RETRIES: usize = 5;

#[derive(Serialize, Deserialize)]
struct IAMFormat {
    version: i32,
}

impl IAMFormat {
    fn new_version_1() -> Self {
        IAMFormat {
            version: IAM_FORMAT_VERSION_1,
        }
    }
}

fn get_iam_format_file_path() -> String {
    path_join_buf(&[&IAM_CONFIG_PREFIX, IAM_FORMAT_FILE])
}

#[repr(u8)]
#[derive(Debug, PartialEq)]
pub enum IamState {
    Uninitialized = 0,
    Loading = 1,
    Ready = 2,
    Error = 3,
}

pub struct IamCache<T> {
    pub cache: Cache,
    pub api: T,
    pub state: Arc<AtomicU8>,
    pub loading: Arc<AtomicBool>,
    pub roles: HashMap<ARN, Vec<String>>,
    pub send_chan: Sender<i64>,
    pub last_timestamp: AtomicI64,
    pub sync_failures: AtomicU64,
    pub sync_successes: AtomicU64,
    pub last_sync_duration_millis: AtomicU64,
}

#[derive(Debug, Clone, Copy, Default)]
pub struct IamSyncMetricsSnapshot {
    pub last_sync_duration_millis: u64,
    pub since_last_sync_millis: u64,
    pub sync_failures: u64,
    pub sync_successes: u64,
}

impl<T> IamCache<T>
where
    T: Store,
{
    async fn verify_temp_user_persistence(&self, access_key: &str) -> Result<()> {
        for attempt in 0..=TEMP_USER_PERSISTENCE_VERIFY_MAX_RETRIES {
            match self.api.load_user_identity(access_key, UserType::Sts).await {
                Ok(_) => return Ok(()),
                Err(err)
                    if attempt < TEMP_USER_PERSISTENCE_VERIFY_MAX_RETRIES
                        && (is_err_no_such_user(&err) || is_err_config_not_found(&err)) =>
                {
                    warn!(
                        access_key,
                        attempt = attempt + 1,
                        max_retries = TEMP_USER_PERSISTENCE_VERIFY_MAX_RETRIES,
                        error = ?err,
                        "temporary IAM user not yet visible after save; retrying persistence verification"
                    );
                    tokio::time::sleep(TEMP_USER_PERSISTENCE_VERIFY_RETRY_DELAY).await;
                }
                Err(err) => return Err(err),
            }
        }

        unreachable!("temp-user persistence verification loop should return on success or terminal error")
    }

    /// Create a new IAM system instance
    /// # Arguments
    /// * `api` - The storage backend implementing the Store trait
    ///
    /// # Returns
    /// An Arc-wrapped instance of IamSystem
    pub(crate) async fn new(api: T) -> Result<Arc<Self>> {
        let (sender, receiver) = mpsc::channel::<i64>(100);

        let sys = Arc::new(Self {
            api,
            cache: Cache::default(),
            state: Arc::new(AtomicU8::new(IamState::Uninitialized as u8)),
            loading: Arc::new(AtomicBool::new(false)),
            send_chan: sender,
            roles: HashMap::new(),
            last_timestamp: AtomicI64::new(0),
            sync_failures: AtomicU64::new(0),
            sync_successes: AtomicU64::new(0),
            last_sync_duration_millis: AtomicU64::new(0),
        });

        sys.clone().init(receiver).await?;
        Ok(sys)
    }

    /// Initialize the IAM system
    async fn init(self: Arc<Self>, receiver: Receiver<i64>) -> Result<()> {
        self.state.store(IamState::Loading as u8, Ordering::SeqCst);
        // Ensure the IAM format file is persisted first
        self.clone().save_iam_formatter().await?;

        // Critical: Load all existing users/policies into memory cache
        const MAX_RETRIES: usize = 3;
        let mut load_error = None;
        for attempt in 0..MAX_RETRIES {
            if let Err(e) = self.clone().load().await {
                if attempt == MAX_RETRIES - 1 {
                    self.state.store(IamState::Error as u8, Ordering::SeqCst);
                    warn!(
                        attempts = MAX_RETRIES,
                        error = ?e,
                        "IAM initial load failed"
                    );
                    load_error = Some(e);
                } else {
                    warn!(attempt = attempt + 1, max_attempts = MAX_RETRIES, "IAM load retry scheduled");
                    tokio::time::sleep(INITIAL_LOAD_RETRY_DELAY).await;
                }
            } else {
                break;
            }
        }

        if let Some(err) = load_error {
            return Err(err);
        }

        self.state.store(IamState::Ready as u8, Ordering::SeqCst);
        debug!(state = "ready", "IAM manager ready");

        // Background ticker for synchronization
        // Check if environment variable is set
        let skip_background_task = get_env_opt_str("RUSTFS_SKIP_BACKGROUND_TASK").is_some();

        if !skip_background_task {
            // Background thread starts periodic updates or receives signal updates
            tokio::spawn({
                let s = Arc::clone(&self);
                async move {
                    let ticker = tokio::time::interval(Duration::from_secs(120));
                    tokio::pin!(ticker, receiver);
                    loop {
                        select! {
                            _ = ticker.tick() => {
                                debug!(source = "ticker", "IAM reload tick");
                                if let Err(err) =s.clone().load().await{
                                    warn!(source = "ticker", error = ?err, "IAM reload failed");
                                }
                            },
                            i = receiver.recv() => {
                                debug!(source = "receiver", "IAM reload signal received");
                                match i {
                                    Some(t) => {
                                        let last = s.last_timestamp.load(Ordering::Relaxed);
                                        if last <= t {
                                            debug!(source = "receiver", "IAM reload accepted");
                                            if let Err(err) =s.clone().load().await{
                                                warn!(source = "receiver", error = ?err, "IAM reload failed");
                                            }
                                            ticker.reset();
                                        }
                                    },
                                    None => return,
                                }
                            }
                        }
                    }
                }
            });
        }

        Ok(())
    }

    /// Check if IAM system is ready
    pub fn is_ready(&self) -> bool {
        self.state.load(Ordering::SeqCst) == IamState::Ready as u8
    }

    async fn _notify(&self) {
        self.send_chan.send(OffsetDateTime::now_utc().unix_timestamp()).await.unwrap();
    }

    async fn load(self: Arc<Self>) -> Result<()> {
        let started_at = std::time::Instant::now();
        match self.api.load_all(&self.cache).await {
            Ok(()) => {
                self.last_timestamp
                    .store(OffsetDateTime::now_utc().unix_timestamp(), Ordering::Relaxed);
                self.sync_successes.fetch_add(1, Ordering::Relaxed);
                self.last_sync_duration_millis
                    .store(started_at.elapsed().as_millis().min(u128::from(u64::MAX)) as u64, Ordering::Relaxed);
                Ok(())
            }
            Err(err) => {
                self.sync_failures.fetch_add(1, Ordering::Relaxed);
                Err(err)
            }
        }
    }

    pub fn sync_metrics_snapshot(&self) -> IamSyncMetricsSnapshot {
        let now_secs = OffsetDateTime::now_utc().unix_timestamp();
        let last_sync_secs = self.last_timestamp.load(Ordering::Relaxed);
        let since_last_sync_millis = if last_sync_secs > 0 && now_secs >= last_sync_secs {
            ((now_secs - last_sync_secs) as u64).saturating_mul(1000)
        } else {
            0
        };

        IamSyncMetricsSnapshot {
            last_sync_duration_millis: self.last_sync_duration_millis.load(Ordering::Relaxed),
            since_last_sync_millis,
            sync_failures: self.sync_failures.load(Ordering::Relaxed),
            sync_successes: self.sync_successes.load(Ordering::Relaxed),
        }
    }

    pub async fn load_user(&self, access_key: &str) -> Result<()> {
        let mut users_map: HashMap<String, UserIdentity> = HashMap::new();
        let mut user_policy_map = HashMap::new();
        let mut sts_users_map = HashMap::new();
        let mut sts_policy_map = HashMap::new();
        let mut policy_docs_map = HashMap::new();

        match self.api.load_user(access_key, UserType::Svc, &mut users_map).await {
            Ok(()) => {}
            Err(err) if is_err_no_such_user(&err) => {}
            Err(err) => return Err(err),
        }

        let parent_user = users_map.get(access_key).map(|svc| svc.credentials.parent_user.clone());

        if let Some(parent_user) = parent_user {
            match self.api.load_user(&parent_user, UserType::Reg, &mut users_map).await {
                Ok(()) => {}
                Err(err) if is_err_no_such_user(&err) => {}
                Err(err) => return Err(err),
            }
            let _ = self
                .api
                .load_mapped_policy(&parent_user, UserType::Reg, false, &mut user_policy_map)
                .await;
        } else {
            match self.api.load_user(access_key, UserType::Reg, &mut users_map).await {
                Ok(()) => {}
                Err(err) if is_err_no_such_user(&err) => {}
                Err(err) => return Err(err),
            }
            if users_map.contains_key(access_key) {
                let _ = self
                    .api
                    .load_mapped_policy(access_key, UserType::Reg, false, &mut user_policy_map)
                    .await;
            }

            match self.api.load_user(access_key, UserType::Sts, &mut sts_users_map).await {
                Ok(()) => {}
                Err(err) if is_err_no_such_user(&err) => {}
                Err(err) => return Err(err),
            }

            let has_sts_user = sts_users_map.get(access_key);

            if let Some(parent) = has_sts_user.map(|sts| sts.credentials.parent_user.clone()) {
                let _ = self
                    .api
                    .load_mapped_policy(&parent, UserType::Sts, false, &mut sts_policy_map)
                    .await;

                if let Some(plc) = sts_policy_map.get(&parent) {
                    for p in plc.to_slice().iter() {
                        if !policy_docs_map.contains_key(p) {
                            let _ = self.api.load_policy_doc(p, &mut policy_docs_map).await;
                        }
                    }
                }
            }
        }

        for plc in user_policy_map.values() {
            for p in plc.to_slice().iter() {
                if !policy_docs_map.contains_key(p) {
                    let _ = self.api.load_policy_doc(p, &mut policy_docs_map).await;
                }
            }
        }

        self.cache.with_write_lock(|cache| {
            let now = OffsetDateTime::now_utc();
            for (key, user) in users_map.iter() {
                cache.add_or_update_user(key, user, now);
            }
            for (key, user_policy) in user_policy_map.iter() {
                cache.add_or_update_user_policy(key, user_policy, now);
            }
            for (key, sts_user) in sts_users_map.iter() {
                cache.add_or_update_sts_account(key, sts_user, now);
            }
            for (key, sts_policy) in sts_policy_map.iter() {
                cache.add_or_update_sts_policy(key, sts_policy, now);
            }
            for (key, policy_doc) in policy_docs_map.iter() {
                cache.add_or_update_policy_doc(key, policy_doc, now);
            }
        });

        Ok(())
    }

    // TODO: Check if exists, whether retry is possible
    #[tracing::instrument(level = "debug", skip(self))]
    async fn save_iam_formatter(self: Arc<Self>) -> Result<()> {
        let path = get_iam_format_file_path();

        let iam_fmt: Format = match self.api.load_iam_config(&path).await {
            Ok(v) => v,
            Err(err) => {
                if !is_err_config_not_found(&err) {
                    return Err(err);
                }

                Format::default()
            }
        };

        if iam_fmt.version >= IAM_FORMAT_VERSION_1 {
            return Ok(());
        }

        if !is_iam_first_cluster_node_local().await {
            return Ok(());
        }

        self.api.save_iam_config(IAMFormat::new_version_1(), path).await
    }
    pub async fn get_user(&self, access_key: &str) -> Option<UserIdentity> {
        let cache = self.cache.snapshot();
        cache
            .users
            .get(access_key)
            .cloned()
            .or_else(|| cache.sts_accounts.get(access_key).cloned())
    }

    pub async fn get_mapped_policy(&self, name: &str, is_group: bool) -> Option<MappedPolicy> {
        let cache = self.cache.snapshot();
        if is_group {
            cache.group_policies.get(name).cloned()
        } else {
            cache.user_policies.get(name).cloned()
        }
    }

    pub async fn get_policy(&self, name: &str) -> Result<Policy> {
        if name.is_empty() {
            return Err(Error::InvalidArgument);
        }

        let policies = MappedPolicy::new(name).to_slice();
        let cache = self.cache.snapshot();
        let policy_docs = Arc::clone(&cache.policy_docs);
        drop(cache);

        let mut to_merge = Vec::new();
        for policy in policies {
            if policy.is_empty() {
                continue;
            }

            let v = policy_docs.get(&policy).cloned().ok_or(Error::NoSuchPolicy)?;

            to_merge.push(v.policy);
        }

        if to_merge.is_empty() {
            return Err(Error::NoSuchPolicy);
        }

        Ok(Policy::merge_policies(to_merge))
    }

    pub async fn get_policy_doc(&self, name: &str) -> Result<PolicyDoc> {
        if name.is_empty() {
            return Err(Error::InvalidArgument);
        }

        self.cache
            .snapshot()
            .policy_docs
            .get(name)
            .cloned()
            .ok_or(Error::NoSuchPolicy)
    }

    pub async fn delete_policy(&self, name: &str, is_from_notify: bool) -> Result<()> {
        if name.is_empty() {
            return Err(Error::InvalidArgument);
        }

        if is_from_notify {
            let cache = self.cache.snapshot();
            let user_policy_cache = Arc::clone(&cache.user_policies);
            let group_policy_cache = Arc::clone(&cache.group_policies);
            let users_cache = Arc::clone(&cache.users);

            let mut users = Vec::new();
            let mut stale_user_policies = Vec::new();
            user_policy_cache.iter().for_each(|(k, v)| {
                if !users_cache.contains_key(k) {
                    stale_user_policies.push(k.to_owned());
                    return;
                }

                if v.policy_set().contains(name) {
                    users.push(k.to_owned());
                }
            });

            let mut groups = Vec::new();
            group_policy_cache.iter().for_each(|(k, v)| {
                if v.policy_set().contains(name) {
                    groups.push(k.to_owned());
                }
            });

            if !stale_user_policies.is_empty() {
                self.cache.with_write_lock(|cache| {
                    let now = OffsetDateTime::now_utc();
                    for user in stale_user_policies.iter() {
                        cache.delete_user_policy(user, now);
                    }
                });
            }

            if !users.is_empty() || !groups.is_empty() {
                return Err(Error::PolicyInUse);
            }

            if let Err(err) = self.api.delete_policy_doc(name).await {
                if !is_err_no_such_policy(&err) {
                    self.cache.delete_policy_doc(name, OffsetDateTime::now_utc());
                    return Ok(());
                }

                return Err(err);
            }
        }

        self.cache.delete_policy_doc(name, OffsetDateTime::now_utc());

        Ok(())
    }

    pub async fn set_policy(&self, name: &str, policy: Policy) -> Result<OffsetDateTime> {
        if name.is_empty() || policy.is_empty() {
            return Err(Error::InvalidArgument);
        }

        let cache = self.cache.snapshot();
        let policy_doc = cache
            .policy_docs
            .get(name)
            .map(|v| {
                let mut p = v.clone();
                p.update(policy.clone());
                p
            })
            .unwrap_or_else(|| PolicyDoc::new(policy));

        self.api.save_policy_doc(name, policy_doc.clone()).await?;

        let now = OffsetDateTime::now_utc();

        self.cache.add_or_update_policy_doc(name, &policy_doc, now);

        Ok(now)
    }

    pub async fn list_polices(&self, bucket_name: &str) -> Result<HashMap<String, Policy>> {
        let mut m = HashMap::new();

        self.api.load_policy_docs(&mut m).await?;
        set_default_canned_policies(&mut m);

        let policy_docs_cache = CacheEntity::new(m.clone());

        self.cache
            .with_write_lock(|cache| cache.replace_policy_docs(policy_docs_cache));

        let items: Vec<_> = m.into_iter().map(|(k, v)| (k, v.policy)).collect();

        let futures: Vec<_> = items.iter().map(|(_, policy)| policy.match_resource(bucket_name)).collect();

        let results = join_all(futures).await;

        let filtered = items
            .into_iter()
            .zip(results)
            .filter_map(|((k, policy), matches)| {
                if bucket_name.is_empty() || matches {
                    Some((k, policy))
                } else {
                    None
                }
            })
            .collect();

        Ok(filtered)
    }

    pub async fn merge_policies(&self, name: &str) -> (String, Policy) {
        let mut policies = Vec::new();
        let mut to_merge = Vec::new();
        let mut miss_policies = Vec::new();
        let cache = self.cache.snapshot();
        let policy_docs = Arc::clone(&cache.policy_docs);
        drop(cache);

        for policy in MappedPolicy::new(name).to_slice() {
            if policy.is_empty() {
                continue;
            }

            if let Some(v) = policy_docs.get(&policy).cloned() {
                policies.push(policy);
                to_merge.push(v.policy);
            } else {
                miss_policies.push(policy);
            }
        }

        if !miss_policies.is_empty() {
            let mut m = HashMap::new();
            for policy in miss_policies {
                let _ = self.api.load_policy_doc(&policy, &mut m).await;
            }

            self.cache.with_write_lock(|cache| {
                let now = OffsetDateTime::now_utc();
                for (k, v) in m.iter() {
                    cache.add_or_update_policy_doc(k, v, now);
                    policies.push(k.clone());
                    to_merge.push(v.policy.clone());
                }
            });
        }

        (policies.join(","), Policy::merge_policies(to_merge))
    }

    pub async fn list_policy_docs(&self, bucket_name: &str) -> Result<HashMap<String, PolicyDoc>> {
        let mut m = HashMap::new();

        self.api.load_policy_docs(&mut m).await?;
        set_default_canned_policies(&mut m);

        let policy_docs_cache = CacheEntity::new(m.clone());

        self.cache
            .with_write_lock(|cache| cache.replace_policy_docs(policy_docs_cache));

        let items: Vec<_> = m.into_iter().collect();

        let futures: Vec<_> = items
            .iter()
            .map(|(_, policy_doc)| policy_doc.policy.match_resource(bucket_name))
            .collect();

        let results = join_all(futures).await;

        let filtered = items
            .into_iter()
            .zip(results)
            .filter_map(|((k, policy_doc), matches)| {
                if bucket_name.is_empty() || matches {
                    Some((k, policy_doc))
                } else {
                    None
                }
            })
            .collect();

        Ok(filtered)
    }

    pub async fn list_policy_docs_internal(&self, bucket_name: &str) -> Result<HashMap<String, PolicyDoc>> {
        let cache = self.cache.snapshot();
        let items: Vec<_> = cache.policy_docs.iter().map(|(k, v)| (k.clone(), v.clone())).collect();

        let futures: Vec<_> = items
            .iter()
            .map(|(_, policy_doc)| policy_doc.policy.match_resource(bucket_name))
            .collect();

        let results = join_all(futures).await;

        let ret = items
            .into_iter()
            .zip(results)
            .filter_map(|((k, policy_doc), matches)| {
                if bucket_name.is_empty() || matches {
                    Some((k, policy_doc))
                } else {
                    None
                }
            })
            .collect();

        Ok(ret)
    }

    pub async fn list_temp_accounts(&self, access_key: &str) -> Result<Vec<UserIdentity>> {
        let cache = self.cache.snapshot();
        let users = Arc::clone(&cache.users);
        let mut user_exists = false;
        let mut ret = Vec::new();

        for (_, v) in users.iter() {
            let is_derived = v.credentials.is_service_account() || v.credentials.is_temp();

            if !is_derived && v.credentials.access_key.as_str() == access_key {
                user_exists = true;
            } else if is_derived && v.credentials.parent_user == access_key {
                user_exists = true;
                if v.credentials.is_temp() {
                    let mut u = v.clone();
                    u.credentials.secret_key = String::new();
                    u.credentials.session_token = String::new();

                    ret.push(u);
                }
            }
        }

        let sts_accounts = Arc::clone(&cache.sts_accounts);
        for (_, v) in sts_accounts.iter() {
            if v.credentials.parent_user == access_key {
                user_exists = true;
                if v.credentials.is_temp() && !v.credentials.is_service_account() {
                    let mut u = v.clone();
                    u.credentials.secret_key = String::new();
                    u.credentials.session_token = String::new();

                    ret.push(u);
                }
            }
        }

        if !user_exists {
            return Err(Error::NoSuchUser(access_key.to_string()));
        }

        Ok(ret)
    }

    pub async fn list_sts_accounts(&self, access_key: &str) -> Result<Vec<Credentials>> {
        let cache = self.cache.snapshot();
        let sts_accounts = Arc::clone(&cache.sts_accounts);
        Ok(sts_accounts
            .values()
            .filter_map(|x| {
                if !access_key.is_empty()
                    && x.credentials.parent_user.as_str() == access_key
                    && x.credentials.is_temp()
                    && !x.credentials.is_service_account()
                {
                    let mut c = x.credentials.clone();
                    c.secret_key = String::new();
                    c.session_token = String::new();
                    return Some(c);
                }

                None
            })
            .collect())
    }

    pub async fn list_service_accounts(&self, access_key: &str) -> Result<Vec<Credentials>> {
        let cache = self.cache.snapshot();
        let users = Arc::clone(&cache.users);
        Ok(users
            .values()
            .filter_map(|x| {
                if !access_key.is_empty()
                    && x.credentials.parent_user.as_str() == access_key
                    && x.credentials.is_service_account()
                {
                    let mut c = x.credentials.clone();
                    c.secret_key = String::new();
                    c.session_token = String::new();
                    return Some(c);
                }

                None
            })
            .collect())
    }

    /// create a service account and update cache
    pub async fn add_service_account(&self, cred: Credentials) -> Result<OffsetDateTime> {
        if cred.access_key.is_empty() || cred.parent_user.is_empty() {
            return Err(Error::InvalidArgument);
        }

        let cache = self.cache.snapshot();
        let users = Arc::clone(&cache.users);
        if let Some(x) = users.get(&cred.access_key)
            && x.credentials.is_service_account()
        {
            return Err(Error::IAMActionNotAllowed);
        }
        drop(cache);
        drop(users);

        let u = UserIdentity::new(cred);

        self.api
            .save_user_identity(&u.credentials.access_key, UserType::Svc, u.clone(), None)
            .await?;

        self.update_user_with_claims(&u.credentials.access_key, u.clone())?;

        Ok(OffsetDateTime::now_utc())
    }

    pub async fn update_service_account(&self, name: &str, opts: UpdateServiceAccountOpts) -> Result<OffsetDateTime> {
        let cache = self.cache.snapshot();
        let Some(ui) = cache.users.get(name).cloned() else {
            return Err(Error::NoSuchServiceAccount(name.to_string()));
        };

        if !ui.credentials.is_service_account() {
            return Err(Error::NoSuchServiceAccount(name.to_string()));
        }
        drop(cache);

        let mut cr = ui.credentials.clone();
        let current_secret_key = cr.secret_key.clone();

        if let Some(secret) = opts.secret_key {
            if !is_secret_key_valid(&secret) {
                return Err(Error::InvalidSecretKeyLength);
            }
            cr.secret_key = secret;
        }

        if opts.name.is_some() {
            cr.name = opts.name;
        }

        if opts.description.is_some() {
            cr.description = opts.description;
        }

        let token_without_expiration = cr.expiration.is_none();

        if opts.expiration.is_some() {
            // TODO: check expiration
            cr.expiration = opts.expiration;
        }

        if let Some(status) = opts.status {
            match status.as_str() {
                val if val == AccountStatus::Enabled.as_ref() => cr.status = auth::ACCOUNT_ON.to_owned(),
                val if val == AccountStatus::Disabled.as_ref() => cr.status = auth::ACCOUNT_OFF.to_owned(),
                auth::ACCOUNT_ON => cr.status = auth::ACCOUNT_ON.to_owned(),
                auth::ACCOUNT_OFF => cr.status = auth::ACCOUNT_OFF.to_owned(),
                _ => cr.status = auth::ACCOUNT_OFF.to_owned(),
            }
        }

        let mut m: HashMap<String, Value> = if token_without_expiration {
            get_claims_from_token_with_secret_allow_missing_exp(&cr.session_token, &current_secret_key)?
        } else {
            get_claims_from_token_with_secret(&cr.session_token, &current_secret_key)?
        };
        m.remove(SESSION_POLICY_NAME_EXTRACTED);

        let nosp = if let Some(policy) = &opts.session_policy {
            policy.version.is_empty() && policy.statements.is_empty()
        } else {
            false
        };

        if m.contains_key(SESSION_POLICY_NAME) && nosp {
            m.remove(SESSION_POLICY_NAME);
            m.insert(iam_policy_claim_name_sa(), Value::String(INHERITED_POLICY_TYPE.to_owned()));
        }

        if let Some(session_policy) = &opts.session_policy {
            session_policy.validate()?;
            if !session_policy.version.is_empty() && !session_policy.statements.is_empty() {
                let policy_buf = serde_json::to_vec(&session_policy)?;
                if policy_buf.len() > MAX_SVCSESSION_POLICY_SIZE {
                    return Err(Error::PolicyTooLarge);
                }

                m.insert(
                    SESSION_POLICY_NAME.to_owned(),
                    Value::String(base64_simd::URL_SAFE_NO_PAD.encode_to_string(&policy_buf)),
                );
                m.insert(iam_policy_claim_name_sa(), Value::String(EMBEDDED_POLICY_TYPE.to_owned()));
            }
        }

        if let Some(expiration) = opts.expiration {
            m.insert("exp".to_owned(), Value::Number(serde_json::Number::from(expiration.unix_timestamp())));
        }

        m.insert("accessKey".to_owned(), Value::String(name.to_owned()));
        if name == SITE_REPLICATOR_SERVICE_ACCOUNT && opts.allow_site_replicator_account {
            m.insert(SITE_REPLICATOR_CLAIM.to_owned(), Value::Bool(true));
        }

        cr.session_token = jwt_sign(&m, &cr.secret_key)?;

        let u = UserIdentity::new(cr);
        self.api
            .save_user_identity(&u.credentials.access_key, UserType::Svc, u.clone(), None)
            .await?;
        self.update_user_with_claims(&u.credentials.access_key, u.clone())?;

        Ok(OffsetDateTime::now_utc())
    }

    pub async fn policy_db_get(&self, name: &str, groups: &Option<Vec<String>>) -> Result<Vec<String>> {
        if name.is_empty() {
            return Err(Error::InvalidArgument);
        }

        let (mut policies, _) = self.policy_db_get_internal(name, false, false).await?;
        let present = !policies.is_empty();

        if let Some(groups) = groups {
            for group in groups.iter() {
                let (gp, _) = match self.policy_db_get_internal(group, true, present).await {
                    Ok(result) => result,
                    Err(err) if is_err_no_such_group(&err) => continue,
                    Err(err) => return Err(err),
                };
                gp.iter().for_each(|v| {
                    policies.push(v.clone());
                });
            }
        }

        Ok(policies)
    }

    async fn policy_db_get_internal(
        &self,
        name: &str,
        is_group: bool,
        policy_present: bool,
    ) -> Result<(Vec<String>, OffsetDateTime)> {
        if is_group {
            let cache = self.cache.snapshot();
            let groups = Arc::clone(&cache.groups);
            drop(cache);

            let g = match groups.get(name) {
                Some(p) => p.clone(),
                None => {
                    let mut m = HashMap::new();
                    self.api.load_group(name, &mut m).await?;
                    if let Some(p) = m.get(name) {
                        self.cache.add_or_update_group(name, p, OffsetDateTime::now_utc());
                    }

                    m.get(name).cloned().ok_or_else(|| Error::NoSuchGroup(name.to_string()))?
                }
            };

            if g.status == STATUS_DISABLED {
                return Ok((Vec::new(), OffsetDateTime::now_utc()));
            }

            let cache = self.cache.snapshot();
            let group_policies = Arc::clone(&cache.group_policies);
            drop(cache);
            if let Some(policy) = group_policies.get(name) {
                return Ok((policy.to_slice(), policy.update_at));
            }

            if !policy_present {
                let mut m = HashMap::new();
                if let Err(err) = self.api.load_mapped_policy(name, UserType::Reg, true, &mut m).await
                    && !is_err_no_such_policy(&err)
                {
                    return Err(err);
                }
                if let Some(p) = m.get(name) {
                    self.cache.add_or_update_group_policy(name, p, OffsetDateTime::now_utc());
                    return Ok((p.to_slice(), p.update_at));
                }

                return Ok((Vec::new(), OffsetDateTime::now_utc()));
            }

            return Ok((Vec::new(), OffsetDateTime::now_utc()));
        }

        let cache = self.cache.snapshot();
        let users = Arc::clone(&cache.users);
        let user_policies = Arc::clone(&cache.user_policies);
        let sts_policies = Arc::clone(&cache.sts_policies);
        let groups_cache = Arc::clone(&cache.groups);
        let group_policies = Arc::clone(&cache.group_policies);
        let user_group_memberships = Arc::clone(&cache.user_group_memberships);
        drop(cache);
        let u = users.get(name).cloned().unwrap_or_default();
        if !u.credentials.is_valid() {
            return Ok((Vec::new(), OffsetDateTime::now_utc()));
        }

        let mp = match user_policies.get(name) {
            Some(p) => p.clone(),
            None => {
                let mut m = HashMap::new();
                if let Err(err) = self.api.load_mapped_policy(name, UserType::Reg, false, &mut m).await
                    && !is_err_no_such_policy(&err)
                {
                    return Err(err);
                }
                if let Some(p) = m.get(name) {
                    self.cache.add_or_update_user_policy(name, p, OffsetDateTime::now_utc());
                    p.clone()
                } else {
                    match sts_policies.get(name) {
                        Some(p) => p.clone(),
                        None => {
                            let mut m = HashMap::new();
                            if let Err(err) = self.api.load_mapped_policy(name, UserType::Sts, false, &mut m).await
                                && !is_err_no_such_policy(&err)
                            {
                                return Err(err);
                            }
                            if let Some(p) = m.get(name) {
                                self.cache.add_or_update_sts_policy(name, p, OffsetDateTime::now_utc());
                                p.clone()
                            } else {
                                MappedPolicy::default()
                            }
                        }
                    }
                }
            }
        };

        let mut policies: HashSet<String> = mp.to_slice().into_iter().collect();

        if let Some(groups) = u.credentials.groups.as_ref() {
            for group in groups.iter() {
                if groups_cache.get(group).filter(|v| v.status == STATUS_DISABLED).is_some() {
                    return Ok((Vec::new(), OffsetDateTime::now_utc()));
                }

                let mp = match group_policies.get(group) {
                    Some(p) => p.clone(),
                    None => {
                        let mut m = HashMap::new();
                        if let Err(err) = self.api.load_mapped_policy(group, UserType::Reg, true, &mut m).await
                            && !is_err_no_such_policy(&err)
                        {
                            return Err(err);
                        }
                        if let Some(p) = m.get(group) {
                            self.cache.add_or_update_group_policy(group, p, OffsetDateTime::now_utc());
                            p.clone()
                        } else {
                            MappedPolicy::default()
                        }
                    }
                };

                mp.to_slice().iter().for_each(|v| {
                    policies.insert(v.clone());
                });
            }
        }

        let update_at = mp.update_at;

        for group in user_group_memberships.get(name).cloned().unwrap_or_default().iter() {
            if groups_cache.get(group).filter(|v| v.status == STATUS_DISABLED).is_some() {
                return Ok((Vec::new(), OffsetDateTime::now_utc()));
            }

            let mp = match group_policies.get(group) {
                Some(p) => p.clone(),
                None => {
                    let mut m = HashMap::new();
                    if let Err(err) = self.api.load_mapped_policy(group, UserType::Reg, true, &mut m).await
                        && !is_err_no_such_policy(&err)
                    {
                        return Err(err);
                    }
                    if let Some(p) = m.get(group) {
                        self.cache.add_or_update_group_policy(group, p, OffsetDateTime::now_utc());
                        p.clone()
                    } else {
                        MappedPolicy::default()
                    }
                }
            };

            mp.to_slice().iter().for_each(|v| {
                policies.insert(v.clone());
            });
        }

        Ok((policies.into_iter().collect(), update_at))
    }
    pub async fn policy_db_set(&self, name: &str, user_type: UserType, is_group: bool, policy: &str) -> Result<OffsetDateTime> {
        if name.is_empty() {
            return Err(Error::InvalidArgument);
        }

        if policy.is_empty() {
            if let Err(err) = self.api.delete_mapped_policy(name, user_type, is_group).await
                && !is_err_no_such_policy(&err)
            {
                return Err(err);
            }

            if is_group {
                self.cache.delete_group_policy(name, OffsetDateTime::now_utc());
            } else if user_type == UserType::Sts {
                self.cache.delete_sts_policy(name, OffsetDateTime::now_utc());
            } else {
                self.cache.delete_user_policy(name, OffsetDateTime::now_utc());
            }

            return Ok(OffsetDateTime::now_utc());
        }

        let mp = MappedPolicy::new(policy);

        let cache = self.cache.snapshot();
        let policy_docs_cache = Arc::clone(&cache.policy_docs);
        drop(cache);
        for p in mp.to_slice() {
            if !policy_docs_cache.contains_key(&p) {
                return Err(Error::NoSuchPolicy);
            }
        }

        self.api
            .save_mapped_policy(name, user_type, is_group, mp.clone(), None)
            .await?;

        if is_group {
            self.cache.add_or_update_group_policy(name, &mp, OffsetDateTime::now_utc());
        } else if user_type == UserType::Sts {
            self.cache.add_or_update_sts_policy(name, &mp, OffsetDateTime::now_utc());
        } else {
            self.cache.add_or_update_user_policy(name, &mp, OffsetDateTime::now_utc());
        }

        Ok(OffsetDateTime::now_utc())
    }

    pub async fn set_temp_user(&self, access_key: &str, cred: &Credentials, policy_name: Option<&str>) -> Result<OffsetDateTime> {
        if access_key.is_empty() || !cred.is_temp() || cred.is_expired() || cred.parent_user.is_empty() {
            error!(
                "set temp user invalid argument, access_key: {},  is_temp: {}, is_expired: {}, parent_user_empty: {}",
                access_key,
                cred.is_temp(),
                cred.is_expired(),
                cred.parent_user.is_empty()
            );
            return Err(Error::InvalidArgument);
        }

        let sts_policy_update = if let Some(policy) = policy_name {
            let mp = MappedPolicy::new(policy);
            let (_, combined_policy_stmt) = filter_policies(&self.cache, &mp.policies, "temp");
            if combined_policy_stmt.is_empty() {
                return Err(Error::other(format!("Required policy not found: {}", IamError::NoSuchPolicy)));
            }

            self.api
                .save_mapped_policy(&cred.parent_user, UserType::Sts, false, mp.clone(), None)
                .await?;

            Some(mp)
        } else {
            None
        };

        let u = UserIdentity::new(cred.clone());
        self.api
            .save_user_identity(access_key, UserType::Sts, u.clone(), None)
            .await?;
        self.verify_temp_user_persistence(access_key).await?;

        let now = self.cache.with_write_lock(|cache| {
            let now = OffsetDateTime::now_utc();
            if let Some(mp) = &sts_policy_update {
                cache.add_or_update_sts_policy(&cred.parent_user, mp, now);
            }
            cache.add_or_update_sts_account(access_key, &u, now);
            now
        });

        Ok(now)
    }

    pub async fn get_user_info(&self, name: &str) -> Result<rustfs_madmin::UserInfo> {
        let cache = self.cache.snapshot();
        let users = Arc::clone(&cache.users);
        let policies = Arc::clone(&cache.user_policies);
        let group_members = Arc::clone(&cache.user_group_memberships);

        let u = match users.get(name) {
            Some(u) => u,
            None => return Err(Error::NoSuchUser(name.to_string())),
        };

        if u.credentials.is_temp() || u.credentials.is_service_account() {
            return Err(Error::IAMActionNotAllowed);
        }

        let mut uinfo = rustfs_madmin::UserInfo {
            status: if u.credentials.is_valid() {
                AccountStatus::Enabled
            } else {
                AccountStatus::Disabled
            },
            updated_at: u.update_at,
            ..Default::default()
        };

        if let Some(p) = policies.get(name) {
            uinfo.policy_name = Some(p.policies.clone());
            uinfo.updated_at = Some(p.update_at);
        }

        if let Some(members) = group_members.get(name) {
            uinfo.member_of = Some(members.iter().cloned().collect());
        }

        Ok(uinfo)
    }

    // returns all users (not STS or service accounts)
    pub async fn get_users(&self) -> Result<HashMap<String, rustfs_madmin::UserInfo>> {
        let mut m = HashMap::new();

        let cache = self.cache.snapshot();
        let users = Arc::clone(&cache.users);
        let policies = Arc::clone(&cache.user_policies);
        let group_members = Arc::clone(&cache.user_group_memberships);

        for (k, v) in users.iter() {
            if v.credentials.is_temp() || v.credentials.is_service_account() {
                continue;
            }

            let mut u = rustfs_madmin::UserInfo {
                status: if v.credentials.is_valid() {
                    AccountStatus::Enabled
                } else {
                    AccountStatus::Disabled
                },
                updated_at: v.update_at,
                ..Default::default()
            };

            if let Some(p) = policies.get(k) {
                u.policy_name = Some(p.policies.clone());
                u.updated_at = Some(p.update_at);
            }

            if let Some(members) = group_members.get(k) {
                u.member_of = Some(members.iter().cloned().collect());
            }

            m.insert(k.clone(), u);
        }

        Ok(m)
    }
    pub async fn get_bucket_users(&self, bucket_name: &str) -> Result<HashMap<String, rustfs_madmin::UserInfo>> {
        let cache = self.cache.snapshot();
        let users = Arc::clone(&cache.users);
        let policies_cache = Arc::clone(&cache.user_policies);
        let group_members = Arc::clone(&cache.user_group_memberships);
        let group_policy_cache = Arc::clone(&cache.group_policies);
        let policy_docs_cache = Arc::clone(&cache.policy_docs);
        drop(cache);

        let mut ret = HashMap::new();

        for (k, v) in users.iter() {
            if v.credentials.is_temp() || v.credentials.is_service_account() {
                continue;
            }

            let mut policies = Vec::new();
            if let Some(p) = policies_cache.get(k) {
                policies.push(p.policies.clone());

                if let Some(groups) = group_members.get(k) {
                    for group in groups {
                        if let Some(p) = group_policy_cache.get(group) {
                            policies.push(p.policies.clone());
                        }
                    }
                }
            }

            let matched_policies = filter_policies_from_docs(policy_docs_cache.as_ref(), &policies.join(","), bucket_name).0;
            if matched_policies.is_empty() {
                continue;
            }

            let mut u = rustfs_madmin::UserInfo {
                policy_name: Some(matched_policies),
                status: if v.credentials.is_valid() {
                    AccountStatus::Enabled
                } else {
                    AccountStatus::Disabled
                },
                updated_at: v.update_at,
                ..Default::default()
            };

            if let Some(members) = group_members.get(k) {
                u.member_of = Some(members.iter().cloned().collect());
            }

            ret.insert(k.clone(), u);
        }

        Ok(ret)
    }
    pub async fn get_users_with_mapped_policies(&self) -> HashMap<String, String> {
        let mut m = HashMap::new();

        let cache = self.cache.snapshot();
        cache.user_policies.iter().for_each(|(k, v)| {
            m.insert(k.clone(), v.policies.clone());
        });

        cache.sts_policies.iter().for_each(|(k, v)| {
            m.insert(k.clone(), v.policies.clone());
        });

        m
    }

    pub async fn add_user(&self, access_key: &str, args: &AddOrUpdateUserReq) -> Result<OffsetDateTime> {
        let cache = self.cache.snapshot();
        let users = Arc::clone(&cache.users);
        if let Some(x) = users.get(access_key) {
            warn!(error = ?x, "IAM user already exists");
            if x.credentials.is_temp() {
                return Err(Error::IAMActionNotAllowed);
            }
        }
        drop(cache);
        drop(users);

        let status = {
            match &args.status {
                AccountStatus::Enabled => auth::ACCOUNT_ON,
                _ => auth::ACCOUNT_OFF,
            }
        };
        let user_entry = UserIdentity::from(Credentials {
            access_key: access_key.to_string(),
            secret_key: args.secret_key.to_string(),
            status: status.to_owned(),
            ..Default::default()
        });

        self.api
            .save_user_identity(access_key, UserType::Reg, user_entry.clone(), None)
            .await?;

        self.update_user_with_claims(access_key, user_entry)?;

        Ok(OffsetDateTime::now_utc())
    }

    pub async fn delete_user(&self, access_key: &str, utype: UserType) -> Result<()> {
        if access_key.is_empty() {
            return Err(Error::InvalidArgument);
        }

        if utype == UserType::Reg {
            let cache = self.cache.snapshot();
            let member_of = cache.user_group_memberships.get(access_key).cloned();
            drop(cache);
            if let Some(member_of) = member_of {
                for member in member_of.iter() {
                    let _ = self
                        .remove_members_from_group(member, vec![access_key.to_string()], false)
                        .await?;
                }
            }

            let mut service_accounts_to_delete = Vec::new();
            let mut temp_accounts_to_delete = HashSet::new();
            let cache = self.cache.snapshot();
            for (_, v) in cache.users.iter() {
                let u = &v.credentials;
                if u.parent_user.as_str() == access_key {
                    if u.is_service_account() {
                        service_accounts_to_delete.push(u.access_key.clone());
                    }

                    if u.is_temp() {
                        temp_accounts_to_delete.insert(u.access_key.clone());
                    }
                }
            }
            for (_, v) in cache.sts_accounts.iter() {
                let u = &v.credentials;
                if u.parent_user.as_str() == access_key {
                    temp_accounts_to_delete.insert(u.access_key.clone());
                }
            }
            drop(cache);

            for access_key in service_accounts_to_delete.iter() {
                let _ = self.api.delete_user_identity(access_key, UserType::Svc).await;
            }
            for access_key in temp_accounts_to_delete.iter() {
                let _ = self.api.delete_user_identity(access_key, UserType::Sts).await;
            }

            self.cache.with_write_lock(|cache| {
                let now = OffsetDateTime::now_utc();
                for access_key in service_accounts_to_delete.iter() {
                    cache.delete_user(access_key, now);
                }
                for access_key in temp_accounts_to_delete.iter() {
                    cache.delete_sts_account(access_key, now);
                    cache.delete_user(access_key, now);
                }
            });
        }

        let _ = self.api.delete_mapped_policy(access_key, utype, false).await;

        self.cache.delete_user_policy(access_key, OffsetDateTime::now_utc());

        if let Err(err) = self.api.delete_user_identity(access_key, utype).await
            && !is_err_no_such_user(&err)
        {
            return Err(err);
        }

        self.cache.with_write_lock(|cache| {
            let now = OffsetDateTime::now_utc();
            if utype == UserType::Sts {
                cache.delete_sts_account(access_key, now);
            }
            cache.delete_user(access_key, now);
        });

        Ok(())
    }

    pub async fn update_user_secret_key(&self, access_key: &str, secret_key: &str) -> Result<()> {
        if access_key.is_empty() || secret_key.is_empty() {
            return Err(Error::InvalidArgument);
        }

        let cache = self.cache.snapshot();
        let users = Arc::clone(&cache.users);
        let u = match users.get(access_key) {
            Some(u) => u,
            None => return Err(Error::NoSuchUser(access_key.to_string())),
        };

        let mut cred = u.credentials.clone();
        cred.secret_key = secret_key.to_string();

        let u = UserIdentity::from(cred);
        drop(cache);
        drop(users);

        self.api
            .save_user_identity(access_key, UserType::Reg, u.clone(), None)
            .await?;

        self.update_user_with_claims(access_key, u)
    }

    /// Add SSH public key for a user (for SFTP authentication)
    pub async fn add_user_ssh_public_key(&self, access_key: &str, public_key: &str) -> Result<()> {
        if access_key.is_empty() || public_key.is_empty() {
            return Err(Error::InvalidArgument);
        }

        let cache = self.cache.snapshot();
        let users = Arc::clone(&cache.users);
        let u = match users.get(access_key) {
            Some(u) => u,
            None => return Err(Error::NoSuchUser(access_key.to_string())),
        };

        let mut user_identity = u.clone();
        user_identity.add_ssh_public_key(public_key);
        drop(cache);
        drop(users);

        self.api
            .save_user_identity(access_key, UserType::Reg, user_identity.clone(), None)
            .await?;

        self.update_user_with_claims(access_key, user_identity)
    }

    pub async fn set_user_status(&self, access_key: &str, status: AccountStatus) -> Result<OffsetDateTime> {
        if access_key.is_empty() {
            return Err(Error::InvalidArgument);
        }

        if !access_key.is_empty() && status != AccountStatus::Enabled && status != AccountStatus::Disabled {
            return Err(Error::InvalidArgument);
        }

        let cache = self.cache.snapshot();
        let users = Arc::clone(&cache.users);
        let u = match users.get(access_key) {
            Some(u) => u,
            None => return Err(Error::NoSuchUser(access_key.to_string())),
        };

        if u.credentials.is_temp() || u.credentials.is_service_account() {
            return Err(Error::IAMActionNotAllowed);
        }

        let status = {
            match status {
                AccountStatus::Enabled => auth::ACCOUNT_ON,
                _ => auth::ACCOUNT_OFF,
            }
        };

        let user_entry = UserIdentity::from(Credentials {
            access_key: access_key.to_string(),
            secret_key: u.credentials.secret_key.clone(),
            status: status.to_owned(),
            ..Default::default()
        });
        drop(cache);
        drop(users);

        self.api
            .save_user_identity(access_key, UserType::Reg, user_entry.clone(), None)
            .await?;

        self.update_user_with_claims(access_key, user_entry)?;

        Ok(OffsetDateTime::now_utc())
    }

    fn update_user_with_claims(&self, k: &str, u: UserIdentity) -> Result<()> {
        let mut u = u;
        if !u.credentials.session_token.is_empty() {
            u.credentials.claims = Some(if u.credentials.expiration.is_none() {
                extract_jwt_claims_allow_missing_exp(&u)?
            } else {
                extract_jwt_claims(&u)?
            });
        }

        if u.credentials.is_temp() && !u.credentials.is_service_account() {
            self.cache.add_or_update_sts_account(k, &u, OffsetDateTime::now_utc());
        } else {
            self.cache.add_or_update_user(k, &u, OffsetDateTime::now_utc());
        }

        Ok(())
    }

    pub async fn is_temp_user(&self, access_key: &str) -> Result<(bool, String)> {
        let u = match self.get_user(access_key).await {
            Some(u) => u,
            None => return Err(Error::NoSuchUser(access_key.to_string())),
        };

        if u.credentials.is_temp() {
            Ok((true, u.credentials.parent_user))
        } else {
            Ok((false, String::new()))
        }
    }

    pub async fn add_users_to_group(&self, group: &str, members: Vec<String>) -> Result<OffsetDateTime> {
        if group.is_empty() {
            return Err(Error::InvalidArgument);
        }

        let cache = self.cache.snapshot();
        let users_cache = Arc::clone(&cache.users);

        for member in members.iter() {
            if let Some(u) = users_cache.get(member) {
                if u.credentials.is_temp() || u.credentials.is_service_account() {
                    return Err(Error::IAMActionNotAllowed);
                }
            } else {
                return Err(Error::NoSuchUser(member.to_string()));
            }
        }

        let gi = match cache.groups.get(group) {
            Some(res) => {
                let mut gi = res.clone();
                let mut uniq_set: HashSet<String, std::collections::hash_map::RandomState> =
                    HashSet::from_iter(gi.members.iter().cloned());
                uniq_set.extend(members.iter().cloned());

                gi.members = uniq_set.into_iter().collect();
                gi
            }
            None => GroupInfo::new(members.clone()),
        };
        drop(cache);

        self.api.save_group_info(group, gi.clone()).await?;

        let now = self.cache.with_write_lock(|cache| {
            let now = OffsetDateTime::now_utc();
            cache.add_or_update_group(group, &gi, now);

            let user_group_memberships = Arc::clone(&cache.state().user_group_memberships);
            members.iter().for_each(|member| {
                let mut m = user_group_memberships.get(member).cloned().unwrap_or_default();
                m.insert(group.to_string());
                cache.add_or_update_user_group_membership(member, &m, now);
            });
            now
        });

        Ok(now)
    }

    pub async fn set_group_status(&self, name: &str, enable: bool) -> Result<OffsetDateTime> {
        if name.is_empty() {
            return Err(Error::InvalidArgument);
        }

        let cache = self.cache.snapshot();
        let groups = Arc::clone(&cache.groups);
        let mut gi = match groups.get(name) {
            Some(gi) => gi.clone(),
            None => return Err(Error::NoSuchGroup(name.to_string())),
        };
        drop(cache);

        if enable {
            gi.status = STATUS_ENABLED.to_owned();
        } else {
            gi.status = STATUS_DISABLED.to_owned();
        }

        self.api.save_group_info(name, gi.clone()).await?;

        self.cache.add_or_update_group(name, &gi, OffsetDateTime::now_utc());

        Ok(OffsetDateTime::now_utc())
    }

    pub async fn get_group_description(&self, name: &str) -> Result<GroupDesc> {
        let cache = self.cache.snapshot();
        let gi = cache
            .groups
            .get(name)
            .cloned()
            .ok_or_else(|| Error::NoSuchGroup(name.to_string()))?;

        let cached_mapped_policy = cache.group_policies.get(name).cloned();
        drop(cache);

        let mapped_policy = if let Some(policy) = cached_mapped_policy {
            Some(policy)
        } else {
            let mut policies = HashMap::new();
            if let Err(err) = self.api.load_mapped_policy(name, UserType::Reg, true, &mut policies).await
                && !is_err_no_such_policy(&err)
            {
                return Err(err);
            }

            if let Some(policy) = policies.get(name).cloned() {
                self.cache
                    .add_or_update_group_policy(name, &policy, OffsetDateTime::now_utc());
                Some(policy)
            } else {
                None
            }
        };

        Ok(build_group_desc(name, gi, mapped_policy))
    }

    pub async fn list_groups(&self) -> Result<Vec<String>> {
        Ok(self.cache.snapshot().groups.keys().cloned().collect())
    }

    pub async fn update_groups(&self) -> Result<Vec<String>> {
        let mut groups_set = HashSet::new();
        let mut groups = HashMap::new();
        self.api.load_groups(&mut groups).await?;

        let mut group_policies = HashMap::new();

        self.api
            .load_mapped_policies(UserType::Reg, true, &mut group_policies)
            .await?;
        self.cache.with_write_lock(|cache| {
            let now = OffsetDateTime::now_utc();
            for (group, gi) in groups.iter() {
                cache.add_or_update_group(group, gi, now);
                groups_set.insert(group.to_string());
            }
            for (group, gi) in group_policies.iter() {
                cache.add_or_update_group_policy(group, gi, now);
                groups_set.insert(group.to_string());
            }
        });

        Ok(groups_set.into_iter().collect())
    }

    pub async fn remove_members_from_group(
        &self,
        name: &str,
        members: Vec<String>,
        update_cache_only: bool,
    ) -> Result<OffsetDateTime> {
        let cache = self.cache.snapshot();
        let mut gi = cache
            .groups
            .get(name)
            .cloned()
            .ok_or_else(|| Error::NoSuchGroup(name.to_string()))?;
        drop(cache);

        let s: HashSet<&String> = HashSet::from_iter(gi.members.iter());
        let d: HashSet<&String> = HashSet::from_iter(members.iter());
        gi.members = s.difference(&d).map(|v| v.to_string()).collect::<Vec<String>>();

        if !update_cache_only {
            self.api.save_group_info(name, gi.clone()).await?;
        }

        let now = self.cache.with_write_lock(|cache| {
            let now = OffsetDateTime::now_utc();
            cache.add_or_update_group(name, &gi, now);

            let user_group_memberships = Arc::clone(&cache.state().user_group_memberships);
            members.iter().for_each(|member| {
                if let Some(m) = user_group_memberships.get(member) {
                    let mut m = m.clone();
                    m.remove(name);
                    cache.add_or_update_user_group_membership(member, &m, now);
                }
            });
            now
        });

        Ok(now)
    }

    pub async fn remove_users_from_group(&self, group: &str, members: Vec<String>) -> Result<OffsetDateTime> {
        if group.is_empty() {
            return Err(Error::InvalidArgument);
        }

        let cache = self.cache.snapshot();
        let users_cache = Arc::clone(&cache.users);
        let groups_cache = Arc::clone(&cache.groups);
        drop(cache);

        for member in members.iter() {
            if let Some(u) = users_cache.get(member) {
                if u.credentials.is_temp() || u.credentials.is_service_account() {
                    return Err(Error::IAMActionNotAllowed);
                }
            } else {
                return Err(Error::NoSuchUser(member.to_string()));
            }
        }

        let gi = if members.is_empty() {
            // Reload from backend so we see latest members (e.g. after user was deleted elsewhere)
            let mut m = HashMap::new();
            self.api.load_group(group, &mut m).await?;
            m.get(group).cloned().ok_or_else(|| Error::NoSuchGroup(group.to_string()))?
        } else {
            groups_cache
                .get(group)
                .cloned()
                .ok_or_else(|| Error::NoSuchGroup(group.to_string()))?
        };

        if members.is_empty() && !gi.members.is_empty() {
            return Err(Error::GroupNotEmpty);
        }

        if members.is_empty() {
            if let Err(err) = self.api.delete_mapped_policy(group, UserType::Reg, true).await
                && !is_err_no_such_policy(&err)
            {
                return Err(err);
            }

            if let Err(err) = self.api.delete_group_info(group).await
                && !is_err_no_such_group(&err)
            {
                return Err(err);
            }

            let now = self.cache.with_write_lock(|cache| {
                let now = OffsetDateTime::now_utc();
                self.remove_group_from_memberships_map_unlocked(cache, group, now);
                cache.delete_group(group, now);
                cache.delete_group_policy(group, now);
                now
            });

            return Ok(now);
        }

        self.remove_members_from_group(group, members, false).await
    }

    fn remove_group_from_memberships_map_unlocked(&self, cache: &mut LockedCache, group: &str, now: OffsetDateTime) {
        let user_group_memberships = Arc::clone(&cache.state().user_group_memberships);
        for (k, v) in user_group_memberships.iter() {
            if v.contains(group) {
                let mut m = v.clone();
                m.remove(group);
                cache.add_or_update_user_group_membership(k, &m, now);
            }
        }
    }

    fn update_group_memberships_map_unlocked(&self, cache: &mut LockedCache, group: &str, gi: &GroupInfo, now: OffsetDateTime) {
        let user_group_memberships = Arc::clone(&cache.state().user_group_memberships);
        for member in gi.members.iter() {
            let mut m = user_group_memberships.get(member).cloned().unwrap_or_default();
            m.insert(group.to_string());
            cache.add_or_update_user_group_membership(member, &m, now);
        }
    }

    fn remove_user_from_cached_groups(&self, cache: &mut LockedCache, user: &str, now: OffsetDateTime) {
        let member_of = cache.state().user_group_memberships.get(user).cloned().unwrap_or_default();
        for group in member_of.iter() {
            if let Some(group_info) = cache.state().groups.get(group).cloned() {
                let mut group_info = group_info;
                group_info.members.retain(|member| member != user);
                cache.add_or_update_group(group, &group_info, now);
            }
        }
        cache.delete_user_group_membership(user, now);
    }

    pub async fn group_notification_handler(&self, group: &str) -> Result<()> {
        let mut m = HashMap::new();
        if let Err(err) = self.api.load_group(group, &mut m).await {
            if !is_err_no_such_group(&err) {
                return Err(err);
            }

            self.cache.with_write_lock(|cache| {
                let now = OffsetDateTime::now_utc();
                self.remove_group_from_memberships_map_unlocked(cache, group, now);
                cache.delete_group(group, now);
                cache.delete_group_policy(group, now);
            });

            return Ok(());
        }

        let gi = m[group].clone();

        self.cache.with_write_lock(|cache| {
            let now = OffsetDateTime::now_utc();
            cache.add_or_update_group(group, &gi, now);
            self.remove_group_from_memberships_map_unlocked(cache, group, now);
            self.update_group_memberships_map_unlocked(cache, group, &gi, now);
        });

        Ok(())
    }

    pub async fn policy_notification_handler(&self, policy: &str) -> Result<()> {
        let mut m = HashMap::new();
        if let Err(err) = self.api.load_policy_doc(policy, &mut m).await {
            if !is_err_no_such_policy(&err) {
                return Err(err);
            }

            self.cache.with_write_lock(|cache| {
                let now = OffsetDateTime::now_utc();
                cache.delete_policy_doc(policy, now);

                let user_policy_cache = Arc::clone(&cache.state().user_policies);
                let users_cache = Arc::clone(&cache.state().users);
                for (k, v) in user_policy_cache.iter() {
                    let mut set = v.policy_set();
                    if set.contains(policy) {
                        if !users_cache.contains_key(k) {
                            cache.delete_user_policy(k, now);
                            continue;
                        }

                        set.remove(policy);

                        let mp = MappedPolicy::new(&set.iter().cloned().collect::<Vec<_>>().join(","));

                        cache.add_or_update_user_policy(k, &mp, now);
                    }
                }

                let group_policy_cache = Arc::clone(&cache.state().group_policies);
                for (k, v) in group_policy_cache.iter() {
                    let mut set = v.policy_set();
                    if set.contains(policy) {
                        set.remove(policy);

                        let mp = MappedPolicy::new(&set.iter().cloned().collect::<Vec<_>>().join(","));
                        cache.add_or_update_group_policy(k, &mp, now);
                    }
                }
            });

            return Ok(());
        }

        self.cache.with_write_lock(|cache| {
            cache.add_or_update_policy_doc(policy, &m[policy], OffsetDateTime::now_utc());
        });

        Ok(())
    }

    pub async fn policy_mapping_notification_handler(&self, name: &str, user_type: UserType, is_group: bool) -> Result<()> {
        let mut m = HashMap::new();
        if let Err(err) = self.api.load_mapped_policy(name, user_type, is_group, &mut m).await {
            if !is_err_no_such_policy(&err) {
                return Err(err);
            }

            self.cache.with_write_lock(|cache| {
                let now = OffsetDateTime::now_utc();
                if is_group {
                    cache.delete_group_policy(name, now);
                } else if user_type == UserType::Sts {
                    cache.delete_sts_policy(name, now);
                } else {
                    cache.delete_user_policy(name, now);
                }
            });

            return Ok(());
        }

        let mp = m[name].clone();

        self.cache.with_write_lock(|cache| {
            let now = OffsetDateTime::now_utc();
            if is_group {
                cache.add_or_update_group_policy(name, &mp, now);
            } else if user_type == UserType::Sts {
                cache.add_or_update_sts_policy(name, &mp, now);
            } else {
                cache.add_or_update_user_policy(name, &mp, now);
            }
        });

        Ok(())
    }
    pub async fn user_notification_handler(&self, name: &str, user_type: UserType) -> Result<()> {
        let mut m = HashMap::new();
        if let Err(err) = self.api.load_user(name, user_type, &mut m).await {
            if !is_err_no_such_user(&err) {
                return Err(err);
            }

            let mut service_accounts_to_delete = Vec::new();
            let mut temp_accounts_to_delete = HashSet::new();
            if user_type == UserType::Reg {
                let cache = self.cache.snapshot();
                for (_, v) in cache.users.iter() {
                    let u = &v.credentials;
                    if u.parent_user.as_str() == name && u.is_service_account() {
                        service_accounts_to_delete.push(u.access_key.clone());
                    }
                }

                for (_, u) in cache.sts_accounts.iter() {
                    let u = &u.credentials;
                    if u.parent_user.as_str() == name {
                        temp_accounts_to_delete.insert(u.access_key.clone());
                    }
                }
                drop(cache);

                for access_key in service_accounts_to_delete.iter() {
                    let _ = self.api.delete_user_identity(access_key, UserType::Svc).await;
                }
                for access_key in temp_accounts_to_delete.iter() {
                    let _ = self.api.delete_user_identity(access_key, UserType::Sts).await;
                }
            }

            self.cache.with_write_lock(|cache| {
                let now = OffsetDateTime::now_utc();
                match user_type {
                    UserType::Sts => cache.delete_sts_account(name, now),
                    UserType::Reg | UserType::Svc => cache.delete_user(name, now),
                    UserType::None => {}
                }
                self.remove_user_from_cached_groups(cache, name, now);
                if user_type == UserType::Reg {
                    for access_key in service_accounts_to_delete.iter() {
                        cache.delete_user(access_key, now);
                    }
                    for access_key in temp_accounts_to_delete.iter() {
                        cache.delete_sts_account(access_key, now);
                        cache.delete_user(access_key, now);
                    }
                }
                cache.delete_user_policy(name, now);
            });

            return Ok(());
        }

        let u = m[name].clone();
        let mut user_policy_update = None;
        let mut sts_policy_update = None;

        match user_type {
            UserType::Sts => {
                let parent_user = u.credentials.parent_user.clone();
                let mut policies = HashMap::new();
                if let Err(err) = self
                    .api
                    .load_mapped_policy(&parent_user, user_type, false, &mut policies)
                    .await
                {
                    if !is_err_no_such_policy(&err) {
                        return Err(err);
                    }
                } else if let Some(policy) = policies.get(&parent_user).cloned() {
                    sts_policy_update = Some((parent_user, policy));
                }
            }
            UserType::Reg => {
                let mut policies = HashMap::new();
                if let Err(err) = self.api.load_mapped_policy(name, user_type, false, &mut policies).await {
                    if !is_err_no_such_policy(&err) {
                        return Err(err);
                    }
                } else if let Some(policy) = policies.get(name).cloned() {
                    user_policy_update = Some((name.to_string(), policy));
                }
            }

            UserType::Svc => {
                let parent_user = u.credentials.parent_user.clone();
                let cache = self.cache.snapshot();
                let parent_user_type = if cache.users.contains_key(&parent_user) {
                    UserType::Reg
                } else {
                    UserType::Sts
                };
                drop(cache);

                if parent_user_type == UserType::Reg {
                    let mut policies = HashMap::new();
                    if let Err(err) = self
                        .api
                        .load_mapped_policy(&parent_user, UserType::Reg, false, &mut policies)
                        .await
                    {
                        if !is_err_no_such_policy(&err) {
                            return Err(err);
                        }
                    } else if let Some(policy) = policies.get(&parent_user).cloned() {
                        user_policy_update = Some((parent_user, policy));
                    }
                } else {
                    let mut policies = HashMap::new();
                    if let Err(err) = self
                        .api
                        .load_mapped_policy(&parent_user, UserType::Sts, false, &mut policies)
                        .await
                    {
                        if !is_err_no_such_policy(&err) {
                            return Err(err);
                        }
                    } else if let Some(policy) = policies.get(&parent_user).cloned() {
                        sts_policy_update = Some((parent_user, policy));
                    }
                }
            }
            UserType::None => {}
        }

        self.cache.with_write_lock(|cache| {
            let now = OffsetDateTime::now_utc();
            match user_type {
                UserType::Sts => {
                    cache.add_or_update_sts_account(name, &u, now);
                }
                UserType::Reg | UserType::Svc => {
                    cache.add_or_update_user(name, &u, now);
                }
                UserType::None => {}
            }

            if let Some((name, policy)) = &user_policy_update {
                cache.add_or_update_user_policy(name, policy, now);
            }
            if let Some((name, policy)) = &sts_policy_update {
                cache.add_or_update_sts_policy(name, policy, now);
            }
        });

        Ok(())
    }
}

pub fn get_default_policyes() -> HashMap<String, PolicyDoc> {
    let default_policies = &DEFAULT_POLICIES;
    default_policies
        .iter()
        .map(|(n, p)| {
            (
                n.to_string(),
                PolicyDoc {
                    version: 1,
                    policy: p.clone(),
                    ..Default::default()
                },
            )
        })
        .collect()
}

fn set_default_canned_policies(policies: &mut HashMap<String, PolicyDoc>) {
    let default_policies = &DEFAULT_POLICIES;
    for (k, v) in default_policies.iter() {
        let name = k.to_string();
        policies.entry(name).or_insert_with(|| PolicyDoc::default_policy(v.clone()));
    }
}

pub fn get_token_signing_key() -> Option<String> {
    crate::root_credentials::token_signing_key()
}

pub fn extract_jwt_claims(u: &UserIdentity) -> Result<HashMap<String, Value>> {
    let Some(sys_key) = get_token_signing_key() else {
        return Err(Error::other("global active sk not init"));
    };

    let keys = vec![&sys_key, &u.credentials.secret_key];

    for key in keys {
        if let Ok(claims) = get_claims_from_token_with_secret(&u.credentials.session_token, key) {
            return Ok(claims);
        }
    }
    Err(Error::other("unable to extract claims"))
}

pub fn extract_jwt_claims_allow_missing_exp(u: &UserIdentity) -> Result<HashMap<String, Value>> {
    let Some(sys_key) = get_token_signing_key() else {
        return Err(Error::other("global active sk not init"));
    };

    let keys = vec![&sys_key, &u.credentials.secret_key];

    for key in keys {
        if let Ok(claims) = get_claims_from_token_with_secret_allow_missing_exp(&u.credentials.session_token, key) {
            return Ok(claims);
        }
    }
    Err(Error::other("unable to extract claims"))
}

fn filter_policies(cache: &Cache, policy_name: &str, bucket_name: &str) -> (String, Policy) {
    let cache = cache.snapshot();
    filter_policies_from_docs(cache.policy_docs.as_ref(), policy_name, bucket_name)
}

fn filter_policies_from_docs(policy_docs: &CacheEntity<PolicyDoc>, policy_name: &str, bucket_name: &str) -> (String, Policy) {
    let mp = MappedPolicy::new(policy_name).to_slice();

    let mut policies = Vec::new();
    let mut to_merge = Vec::new();
    for policy in mp {
        if policy.is_empty() {
            continue;
        }

        if let Some(p) = policy_docs.get(&policy)
            && (bucket_name.is_empty() || pollster::block_on(p.policy.match_resource(bucket_name)))
        {
            policies.push(policy);
            to_merge.push(p.policy.clone());
        }
    }

    (policies.join(","), Policy::merge_policies(to_merge))
}

fn build_group_desc(name: &str, group_info: GroupInfo, mapped_policy: Option<MappedPolicy>) -> GroupDesc {
    let (policy, updated_at) = mapped_policy
        .map(|policy| (policy.policies, Some(policy.update_at)))
        .unwrap_or_else(|| (String::new(), Some(OffsetDateTime::now_utc())));

    GroupDesc {
        name: name.to_string(),
        policy,
        members: group_info.members,
        updated_at,
        status: group_info.status,
    }
}

#[cfg(test)]
mod tests {
    use super::*;
    use rustfs_policy::policy::{Policy, PolicyDoc};
    use serde_json::json;
    use std::{
        collections::HashMap,
        sync::{
            Arc, Mutex,
            atomic::{AtomicUsize, Ordering},
        },
    };

    #[derive(Clone)]
    struct FailingInitialLoadStore;

    #[async_trait::async_trait]
    impl Store for FailingInitialLoadStore {
        fn has_watcher(&self) -> bool {
            false
        }

        async fn save_iam_config<Item: Serialize + Send>(&self, _item: Item, _path: impl AsRef<str> + Send) -> Result<()> {
            Ok(())
        }

        async fn load_iam_config<Item: serde::de::DeserializeOwned>(&self, _path: impl AsRef<str> + Send) -> Result<Item> {
            Err(Error::ConfigNotFound)
        }

        async fn delete_iam_config(&self, _path: impl AsRef<str> + Send) -> Result<()> {
            Err(Error::InvalidArgument)
        }

        async fn save_user_identity(
            &self,
            _name: &str,
            _user_type: UserType,
            _item: UserIdentity,
            _ttl: Option<usize>,
        ) -> Result<()> {
            Err(Error::InvalidArgument)
        }

        async fn delete_user_identity(&self, _name: &str, _user_type: UserType) -> Result<()> {
            Err(Error::InvalidArgument)
        }

        async fn load_user_identity(&self, _name: &str, _user_type: UserType) -> Result<UserIdentity> {
            Err(Error::InvalidArgument)
        }

        async fn load_user(&self, _name: &str, _user_type: UserType, _m: &mut HashMap<String, UserIdentity>) -> Result<()> {
            Err(Error::InvalidArgument)
        }

        async fn load_users(&self, _user_type: UserType, _m: &mut HashMap<String, UserIdentity>) -> Result<()> {
            Err(Error::InvalidArgument)
        }

        async fn load_secret_key(&self, _name: &str, _user_type: UserType) -> Result<String> {
            Err(Error::InvalidArgument)
        }

        async fn save_group_info(&self, _name: &str, _item: GroupInfo) -> Result<()> {
            Err(Error::InvalidArgument)
        }

        async fn delete_group_info(&self, _name: &str) -> Result<()> {
            Err(Error::InvalidArgument)
        }

        async fn load_group(&self, _name: &str, _m: &mut HashMap<String, GroupInfo>) -> Result<()> {
            Err(Error::InvalidArgument)
        }

        async fn load_groups(&self, _m: &mut HashMap<String, GroupInfo>) -> Result<()> {
            Err(Error::InvalidArgument)
        }

        async fn save_policy_doc(&self, _name: &str, _item: PolicyDoc) -> Result<()> {
            Err(Error::InvalidArgument)
        }

        async fn delete_policy_doc(&self, _name: &str) -> Result<()> {
            Err(Error::InvalidArgument)
        }

        async fn load_policy(&self, _name: &str) -> Result<PolicyDoc> {
            Err(Error::InvalidArgument)
        }

        async fn load_policy_doc(&self, _name: &str, _m: &mut HashMap<String, PolicyDoc>) -> Result<()> {
            Err(Error::InvalidArgument)
        }

        async fn load_policy_docs(&self, _m: &mut HashMap<String, PolicyDoc>) -> Result<()> {
            Err(Error::InvalidArgument)
        }

        async fn save_mapped_policy(
            &self,
            _name: &str,
            _user_type: UserType,
            _is_group: bool,
            _item: MappedPolicy,
            _ttl: Option<usize>,
        ) -> Result<()> {
            Err(Error::InvalidArgument)
        }

        async fn delete_mapped_policy(&self, _name: &str, _user_type: UserType, _is_group: bool) -> Result<()> {
            Err(Error::InvalidArgument)
        }

        async fn load_mapped_policy(
            &self,
            _name: &str,
            _user_type: UserType,
            _is_group: bool,
            _m: &mut HashMap<String, MappedPolicy>,
        ) -> Result<()> {
            Err(Error::InvalidArgument)
        }

        async fn load_mapped_policies(
            &self,
            _user_type: UserType,
            _is_group: bool,
            _m: &mut HashMap<String, MappedPolicy>,
        ) -> Result<()> {
            Err(Error::InvalidArgument)
        }

        async fn load_all(&self, _cache: &Cache) -> Result<()> {
            Err(Error::Io(std::io::Error::other("initial load failed")))
        }
    }

    #[derive(Clone)]
    struct DelayedTempUserVisibilityStore {
        saved_user: Arc<Mutex<Option<UserIdentity>>>,
        load_attempts: Arc<AtomicUsize>,
        visible_after_attempt: usize,
    }

    impl DelayedTempUserVisibilityStore {
        fn new(visible_after_attempt: usize) -> Self {
            Self {
                saved_user: Arc::new(Mutex::new(None)),
                load_attempts: Arc::new(AtomicUsize::new(0)),
                visible_after_attempt,
            }
        }
    }

    #[async_trait::async_trait]
    impl Store for DelayedTempUserVisibilityStore {
        fn has_watcher(&self) -> bool {
            false
        }

        async fn save_iam_config<Item: Serialize + Send>(&self, _item: Item, _path: impl AsRef<str> + Send) -> Result<()> {
            Ok(())
        }

        async fn load_iam_config<Item: serde::de::DeserializeOwned>(&self, _path: impl AsRef<str> + Send) -> Result<Item> {
            Err(Error::ConfigNotFound)
        }

        async fn delete_iam_config(&self, _path: impl AsRef<str> + Send) -> Result<()> {
            Err(Error::InvalidArgument)
        }

        async fn save_user_identity(
            &self,
            _name: &str,
            _user_type: UserType,
            item: UserIdentity,
            _ttl: Option<usize>,
        ) -> Result<()> {
            *self.saved_user.lock().expect("saved_user mutex poisoned") = Some(item);
            Ok(())
        }

        async fn delete_user_identity(&self, _name: &str, _user_type: UserType) -> Result<()> {
            Err(Error::InvalidArgument)
        }

        async fn load_user_identity(&self, name: &str, _user_type: UserType) -> Result<UserIdentity> {
            let attempt = self.load_attempts.fetch_add(1, Ordering::SeqCst) + 1;
            if attempt <= self.visible_after_attempt {
                return Err(Error::NoSuchUser(name.to_string()));
            }

            self.saved_user
                .lock()
                .expect("saved_user mutex poisoned")
                .clone()
                .ok_or_else(|| Error::NoSuchUser(name.to_string()))
        }

        async fn load_user(&self, _name: &str, _user_type: UserType, _m: &mut HashMap<String, UserIdentity>) -> Result<()> {
            Err(Error::InvalidArgument)
        }

        async fn load_users(&self, _user_type: UserType, _m: &mut HashMap<String, UserIdentity>) -> Result<()> {
            Err(Error::InvalidArgument)
        }

        async fn load_secret_key(&self, _name: &str, _user_type: UserType) -> Result<String> {
            Err(Error::InvalidArgument)
        }

        async fn save_group_info(&self, _name: &str, _item: GroupInfo) -> Result<()> {
            Err(Error::InvalidArgument)
        }

        async fn delete_group_info(&self, _name: &str) -> Result<()> {
            Err(Error::InvalidArgument)
        }

        async fn load_group(&self, _name: &str, _m: &mut HashMap<String, GroupInfo>) -> Result<()> {
            Err(Error::InvalidArgument)
        }

        async fn load_groups(&self, _m: &mut HashMap<String, GroupInfo>) -> Result<()> {
            Err(Error::InvalidArgument)
        }

        async fn save_policy_doc(&self, _name: &str, _item: PolicyDoc) -> Result<()> {
            Err(Error::InvalidArgument)
        }

        async fn delete_policy_doc(&self, _name: &str) -> Result<()> {
            Err(Error::InvalidArgument)
        }

        async fn load_policy(&self, _name: &str) -> Result<PolicyDoc> {
            Err(Error::InvalidArgument)
        }

        async fn load_policy_doc(&self, _name: &str, _m: &mut HashMap<String, PolicyDoc>) -> Result<()> {
            Err(Error::InvalidArgument)
        }

        async fn load_policy_docs(&self, _m: &mut HashMap<String, PolicyDoc>) -> Result<()> {
            Err(Error::InvalidArgument)
        }

        async fn save_mapped_policy(
            &self,
            _name: &str,
            _user_type: UserType,
            _is_group: bool,
            _item: MappedPolicy,
            _ttl: Option<usize>,
        ) -> Result<()> {
            Ok(())
        }

        async fn delete_mapped_policy(&self, _name: &str, _user_type: UserType, _is_group: bool) -> Result<()> {
            Err(Error::InvalidArgument)
        }

        async fn load_mapped_policy(
            &self,
            _name: &str,
            _user_type: UserType,
            _is_group: bool,
            _m: &mut HashMap<String, MappedPolicy>,
        ) -> Result<()> {
            Err(Error::InvalidArgument)
        }

        async fn load_mapped_policies(
            &self,
            _user_type: UserType,
            _is_group: bool,
            _m: &mut HashMap<String, MappedPolicy>,
        ) -> Result<()> {
            Err(Error::InvalidArgument)
        }

        async fn load_all(&self, _cache: &Cache) -> Result<()> {
            Ok(())
        }
    }

    fn build_test_temp_credentials() -> Credentials {
        Credentials {
            access_key: "STSACCESS123".to_string(),
            secret_key: "test-secret-key".to_string(),
            session_token: "test-session-token".to_string(),
            expiration: Some(OffsetDateTime::now_utc() + time::Duration::hours(1)),
            status: STATUS_ENABLED.to_string(),
            parent_user: "parent-user".to_string(),
            groups: Some(vec!["console-admins".to_string()]),
            claims: None,
            name: None,
            description: None,
        }
    }

    fn build_test_iam_cache<T: Store>(api: T) -> IamCache<T> {
        let (sender, _receiver) = mpsc::channel::<i64>(1);
        IamCache {
            cache: Cache::default(),
            api,
            state: Arc::new(AtomicU8::new(IamState::Ready as u8)),
            loading: Arc::new(AtomicBool::new(false)),
            roles: HashMap::new(),
            send_chan: sender,
            last_timestamp: AtomicI64::new(0),
            sync_failures: AtomicU64::new(0),
            sync_successes: AtomicU64::new(0),
            last_sync_duration_millis: AtomicU64::new(0),
        }
    }

    #[tokio::test]
    async fn set_temp_user_retries_until_sts_identity_becomes_visible() {
        let store = DelayedTempUserVisibilityStore::new(2);
        let cache = build_test_iam_cache(store.clone());
        let cred = build_test_temp_credentials();

        let updated_at = cache
            .set_temp_user(&cred.access_key, &cred, None)
            .await
            .expect("temp user should succeed once persistence becomes visible");

        assert!(updated_at <= OffsetDateTime::now_utc());
        assert_eq!(store.load_attempts.load(Ordering::SeqCst), 3);

        let snapshot = cache.cache.snapshot();
        let sts_identity = snapshot
            .sts_accounts
            .get(&cred.access_key)
            .expect("verified temp user should be cached");
        assert_eq!(sts_identity.credentials.parent_user, cred.parent_user);
    }

    #[tokio::test]
    async fn set_temp_user_fails_when_sts_identity_never_becomes_visible() {
        let store = DelayedTempUserVisibilityStore::new(TEMP_USER_PERSISTENCE_VERIFY_MAX_RETRIES + 1);
        let cache = build_test_iam_cache(store.clone());
        let cred = build_test_temp_credentials();

        let err = cache
            .set_temp_user(&cred.access_key, &cred, None)
            .await
            .expect_err("temp user should fail when persistence never becomes visible");

        assert!(matches!(err, Error::NoSuchUser(user) if user == cred.access_key));
        assert_eq!(store.load_attempts.load(Ordering::SeqCst), TEMP_USER_PERSISTENCE_VERIFY_MAX_RETRIES + 1);

        let snapshot = cache.cache.snapshot();
        assert!(
            !snapshot.sts_accounts.contains_key(&cred.access_key),
            "cache must not publish a temp user that was not durably visible"
        );
    }

    #[tokio::test]
    async fn test_init_keeps_error_state_when_initial_load_fails() {
        let (sender, receiver) = mpsc::channel::<i64>(1);
        let sys = Arc::new(IamCache {
            api: FailingInitialLoadStore,
            cache: Cache::default(),
            state: Arc::new(AtomicU8::new(IamState::Uninitialized as u8)),
            loading: Arc::new(AtomicBool::new(false)),
            send_chan: sender,
            roles: HashMap::new(),
            last_timestamp: AtomicI64::new(0),
            sync_failures: AtomicU64::new(0),
            sync_successes: AtomicU64::new(0),
            last_sync_duration_millis: AtomicU64::new(0),
        });

        let result = Arc::clone(&sys).init(receiver).await;

        assert!(matches!(result, Err(Error::Io(_))));
        assert!(!sys.is_ready());
        assert_eq!(sys.state.load(Ordering::SeqCst), IamState::Error as u8);
        assert_eq!(sys.sync_failures.load(Ordering::Relaxed), 3);
    }

    #[test]
    fn test_iam_format_new_version_1() {
        let format = IAMFormat::new_version_1();
        assert_eq!(format.version, IAM_FORMAT_VERSION_1);
        assert_eq!(format.version, 1);
    }

    #[test]
    fn test_get_iam_format_file_path() {
        let path = get_iam_format_file_path();
        assert!(path.contains(IAM_FORMAT_FILE));
        assert!(path.contains(&*IAM_CONFIG_PREFIX));
        assert_eq!(path, format!("{}/{}", *IAM_CONFIG_PREFIX, IAM_FORMAT_FILE));
    }

    #[test]
    fn test_get_default_policies() {
        let policies = get_default_policyes();

        // Should contain some default policies
        assert!(!policies.is_empty());

        // Check that all values are PolicyDoc
        for (name, policy_doc) in &policies {
            assert!(!name.is_empty());
            // PolicyDoc.version is i64, not String
            assert!(policy_doc.version >= 0);
        }
    }

    #[test]
    fn test_get_token_signing_key() {
        // This function returns the global action credential's secret key
        // In test environment, it might be None
        let key = get_token_signing_key();
        // Just verify it doesn't panic and returns an Option
        if let Some(k) = key {
            assert!(!k.is_empty());
        } // This is acceptable in test environment when None
    }

    #[test]
    fn test_extract_jwt_claims_basic() {
        let user_identity = UserIdentity {
            version: 1,
            credentials: Credentials {
                access_key: "test-access-key".to_string(),
                secret_key: "test-secret-key".to_string(),
                session_token: "invalid-token".to_string(), // Invalid token for testing error handling
                expiration: None,
                status: "enabled".to_string(),
                parent_user: "".to_string(),
                groups: None,
                claims: Some({
                    let mut claims = HashMap::new();
                    claims.insert("sub".to_string(), json!("test-user"));
                    claims.insert("aud".to_string(), json!("test-audience"));
                    claims
                }),
                name: None,
                description: None,
            },
            update_at: Some(OffsetDateTime::now_utc()),
        };

        let result = extract_jwt_claims(&user_identity);
        // In test environment without proper JWT setup, this should fail
        assert!(result.is_err());
    }

    #[test]
    fn test_extract_jwt_claims_no_claims() {
        let user_identity = UserIdentity {
            version: 1,
            credentials: Credentials {
                access_key: "test-access-key".to_string(),
                secret_key: "test-secret-key".to_string(),
                session_token: "".to_string(), // Empty token
                expiration: None,
                status: "enabled".to_string(),
                parent_user: "".to_string(),
                groups: None,
                claims: None,
                name: None,
                description: None,
            },
            update_at: Some(OffsetDateTime::now_utc()),
        };

        let result = extract_jwt_claims(&user_identity);
        // Should fail with empty session token
        assert!(result.is_err());
    }

    #[test]
    fn test_filter_policies_empty_bucket() {
        let cache = Cache::default();
        let policy_name = "test-policy";
        let bucket_name = "";

        let (name, policy) = filter_policies(&cache, policy_name, bucket_name);

        // When cache is empty, should return empty name and empty policy
        assert_eq!(name, "");
        assert!(policy.statements.is_empty());
    }

    #[test]
    fn test_filter_policies_with_bucket() {
        let cache = Cache::default();
        let policy_name = "test-policy";
        let bucket_name = "test-bucket";

        let (name, policy) = filter_policies(&cache, policy_name, bucket_name);

        // When cache is empty, should return empty name and empty policy regardless of bucket
        assert_eq!(name, "");
        assert!(policy.statements.is_empty());
    }

    #[test]
    fn test_constants() {
        // Test that constants are properly defined
        assert_eq!(IAM_FORMAT_FILE, "format.json");
        assert_eq!(IAM_FORMAT_VERSION_1, 1);
    }

    #[test]
    fn test_iam_format_serialization() {
        let format = IAMFormat::new_version_1();

        // Test serialization
        let serialized = serde_json::to_string(&format).unwrap();
        assert!(serialized.contains("\"version\":1"));

        // Test deserialization
        let deserialized: IAMFormat = serde_json::from_str(&serialized).unwrap();
        assert_eq!(deserialized.version, format.version);
    }

    #[test]
    fn test_mapped_policy_operations() {
        let policy_name = "test-policy";
        let mapped_policy = MappedPolicy::new(policy_name);

        // Test that MappedPolicy can be created
        let policies = mapped_policy.to_slice();
        assert!(!policies.is_empty());
        assert!(policies.iter().any(|p| p.contains(policy_name)));
    }

    #[test]
    fn test_user_identity_structure() {
        let credentials = Credentials {
            access_key: "AKIAIOSFODNN7EXAMPLE".to_string(),
            secret_key: "wJalrXUtnFEMI/K7MDENG/bPxRfiCYEXAMPLEKEY".to_string(),
            session_token: "".to_string(),
            expiration: None,
            status: "enabled".to_string(),
            parent_user: "parent-user".to_string(),
            groups: Some(vec!["group1".to_string(), "group2".to_string()]),
            claims: None,
            name: None,
            description: None,
        };

        let user_identity = UserIdentity {
            version: 1,
            credentials,
            update_at: Some(OffsetDateTime::now_utc()),
        };

        // Test basic structure
        assert_eq!(user_identity.version, 1);
        assert_eq!(user_identity.credentials.access_key, "AKIAIOSFODNN7EXAMPLE");
        assert_eq!(user_identity.credentials.secret_key, "wJalrXUtnFEMI/K7MDENG/bPxRfiCYEXAMPLEKEY");
        assert_eq!(user_identity.credentials.status, "enabled");
        assert_eq!(user_identity.credentials.parent_user, "parent-user");
        assert_eq!(user_identity.credentials.groups, Some(vec!["group1".to_string(), "group2".to_string()]));
    }

    #[test]
    fn test_policy_structure() {
        let policy = Policy {
            id: Default::default(),
            version: "2012-10-17".to_string(),
            statements: vec![],
        };

        // Test basic structure
        assert_eq!(policy.version, "2012-10-17");
        assert_eq!(policy.statements.len(), 0);
        assert!(policy.is_empty());
    }

    #[test]
    fn test_policy_doc_structure() {
        let policy = Policy {
            id: Default::default(),
            version: "2012-10-17".to_string(),
            statements: vec![],
        };

        let policy_doc = PolicyDoc {
            version: 1,
            policy,
            create_date: Some(OffsetDateTime::now_utc()),
            update_date: Some(OffsetDateTime::now_utc()),
        };

        // Test basic structure
        assert_eq!(policy_doc.version, 1);
        assert_eq!(policy_doc.policy.version, "2012-10-17");
        assert!(policy_doc.policy.statements.is_empty());
    }

    #[test]
    fn test_group_info_basic() {
        // Test that GroupInfo can be created and used
        let group_info = GroupInfo {
            version: 1,
            status: STATUS_ENABLED.to_string(),
            members: vec!["user1".to_string(), "user2".to_string()],
            update_at: Some(OffsetDateTime::now_utc()),
        };

        assert_eq!(group_info.version, 1);
        assert_eq!(group_info.status, STATUS_ENABLED);
        assert_eq!(group_info.members.len(), 2);
        assert!(group_info.members.contains(&"user1".to_string()));
        assert!(group_info.members.contains(&"user2".to_string()));
    }

    #[test]
    fn test_update_service_account_opts() {
        let policy = Policy {
            id: Default::default(),
            version: "2012-10-17".to_string(),
            statements: vec![],
        };

        let opts = UpdateServiceAccountOpts {
            secret_key: Some("new-secret-key".to_string()),
            status: Some(STATUS_ENABLED.to_string()),
            name: Some("service-account-name".to_string()),
            description: Some("Updated service account".to_string()),
            expiration: None,
            session_policy: Some(policy),
            allow_site_replicator_account: false,
        };

        assert_eq!(opts.secret_key, Some("new-secret-key".to_string()));
        assert_eq!(opts.status, Some(STATUS_ENABLED.to_string()));
        assert_eq!(opts.name, Some("service-account-name".to_string()));
        assert_eq!(opts.description, Some("Updated service account".to_string()));
        assert!(opts.session_policy.is_some());
        assert!(opts.expiration.is_none());
    }

    #[test]
    fn test_status_constants() {
        // Test that status constants are properly defined
        assert_eq!(STATUS_ENABLED, "enabled");
        assert_eq!(STATUS_DISABLED, "disabled");
    }

    #[test]
    fn test_session_policy_constants() {
        // Test session policy related constants - these are compile-time constants
        // so we just verify they exist and have expected values
        assert_eq!(SESSION_POLICY_NAME, "sessionPolicy");
        assert_eq!(SESSION_POLICY_NAME_EXTRACTED, "sessionPolicy-extracted");
        // MAX_SVCSESSION_POLICY_SIZE is a positive constant defined at compile time
        assert_eq!(MAX_SVCSESSION_POLICY_SIZE, 4096); // Verify the actual expected value
    }

    #[test]
    fn test_credentials_validation() {
        let credentials = Credentials {
            access_key: "AKIAIOSFODNN7EXAMPLE".to_string(),
            secret_key: "wJalrXUtnFEMI/K7MDENG/bPxRfiCYEXAMPLEKEY".to_string(),
            session_token: "".to_string(),
            expiration: None,
            status: "on".to_string(),
            parent_user: "".to_string(),
            groups: None,
            claims: None,
            name: None,
            description: None,
        };

        // Test validation methods
        assert!(credentials.is_valid());
        assert!(!credentials.is_expired());
        assert!(!credentials.is_temp());
        assert!(!credentials.is_service_account());
    }

    #[test]
    fn test_credentials_with_session_token() {
        let credentials = Credentials {
            access_key: "AKIAIOSFODNN7EXAMPLE".to_string(),
            secret_key: "wJalrXUtnFEMI/K7MDENG/bPxRfiCYEXAMPLEKEY".to_string(),
            session_token: "session-token".to_string(),
            expiration: Some(OffsetDateTime::now_utc() + time::Duration::hours(1)),
            status: "on".to_string(),
            parent_user: "".to_string(),
            groups: None,
            claims: None,
            name: None,
            description: None,
        };

        // Test temp credentials
        assert!(credentials.is_valid());
        assert!(!credentials.is_expired());
        assert!(credentials.is_temp());
    }

    #[test]
    fn test_policy_merge() {
        let policy1 = Policy {
            id: Default::default(),
            version: "2012-10-17".to_string(),
            statements: vec![],
        };

        let policy2 = Policy {
            id: Default::default(),
            version: "2012-10-17".to_string(),
            statements: vec![],
        };

        let merged = Policy::merge_policies(vec![policy1, policy2]);
        assert_eq!(merged.version, "2012-10-17");
        assert!(merged.statements.is_empty());
        assert!(merged.is_empty());
    }

    #[test]
    fn test_build_group_desc_preserves_policy_for_disabled_group() {
        let group_info = GroupInfo {
            status: STATUS_DISABLED.to_string(),
            members: vec!["alice".to_string()],
            ..Default::default()
        };
        let mapped_policy = MappedPolicy::new("readonly");

        let desc = build_group_desc("ops", group_info, Some(mapped_policy));

        assert_eq!(desc.name, "ops");
        assert_eq!(desc.status, STATUS_DISABLED);
        assert_eq!(desc.policy, "readonly");
        assert_eq!(desc.members, vec!["alice".to_string()]);
        assert!(desc.updated_at.is_some());
    }
}