macltok

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use std::sync::Arc;
#[cfg(feature = "sqlite")]
use std::{collections::BTreeSet, path::PathBuf};

use ruma::TransactionId;

use crate::{
    AccountError, EncryptedSessionStore, OAuthLogin, PasswordLogin, PendingOAuthLogin, Restore,
    Session, SessionRecord, SessionStore, SoftLogout, StoreConfig, account::homeserver_input,
    engine::StoreLock,
};

/// every account one owner has, a store each under one root and one passphrase. whoever holds
/// the set can resume any soft-logged-out device in it with just its password, and the device's
/// store has its e2ee keys, so a set belongs to one person and never to a whole machine
pub struct Accounts {
    root: Root,
    passphrase: String,
}

enum Root {
    #[cfg(feature = "sqlite")]
    Directory(PathBuf),
    #[cfg(feature = "indexeddb")]
    Prefix(String),
}

/// one account's record and store
#[derive(Clone)]
pub struct Account {
    id: String,
    sessions: Arc<EncryptedSessionStore>,
}

impl Account {
    /// stable for the account's life, and safe in a cookie or a url
    #[must_use]
    pub fn id(&self) -> &str {
        &self.id
    }

    /// for `Termination::retain`. a discarded account drops out of `Accounts::list`
    #[must_use]
    pub fn sessions(&self) -> Arc<dyn SessionStore> {
        self.sessions.clone()
    }

    pub async fn restore(&self) -> Result<Option<Restore>, AccountError> {
        Session::restore(self.sessions()).await
    }
}

impl std::fmt::Debug for Account {
    fn fmt(&self, formatter: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        formatter
            .debug_struct("Account")
            .field("id", &self.id)
            .finish_non_exhaustive()
    }
}

enum Found {
    Nobody,
    SoftLoggedOut(Account, SoftLogout),
}

impl Accounts {
    /// each account is a store directory under `root` with its record beside it
    #[cfg(feature = "sqlite")]
    #[must_use]
    pub fn sqlite(root: impl Into<PathBuf>, passphrase: impl Into<String>) -> Self {
        Self {
            root: Root::Directory(root.into()),
            passphrase: passphrase.into(),
        }
    }

    /// each account is a store named `<prefix>::<id>`, listed in `<prefix>::macltok-accounts`
    #[cfg(feature = "indexeddb")]
    #[must_use]
    pub fn indexeddb(prefix: impl Into<String>, passphrase: impl Into<String>) -> Self {
        Self {
            root: Root::Prefix(prefix.into()),
            passphrase: passphrase.into(),
        }
    }

    /// `None` for anything `Account::id` couldn't have been
    #[must_use]
    pub fn account(&self, id: &str) -> Option<Account> {
        let valid =
            !id.is_empty() && id.len() <= 64 && id.bytes().all(|b| b.is_ascii_alphanumeric());
        valid.then(|| self.open(id.to_owned()))
    }

    /// every account with a record. a store left without one, by a login that died halfway or a
    /// discard that couldn't finish, is deleted on the way past
    pub async fn list(&self) -> Result<Vec<Account>, AccountError> {
        let mut accounts = Vec::new();
        for account in self.slots().await? {
            match account.sessions.load().await {
                Ok(None) => self.sweep(&account).await,
                Ok(Some(_)) | Err(_) => accounts.push(account),
            }
        }
        Ok(accounts)
    }

    /// a soft-logged-out account the login names is resumed as its own device, keeping its keys.
    /// anyone else gets a new account
    pub async fn login_password(
        &self,
        login: PasswordLogin,
    ) -> Result<(Account, Session), AccountError> {
        homeserver_input(&login.homeserver, login.allow_insecure_loopback)?;
        let found = self
            .find(|record| record_names(record, &login.homeserver, &login.username))
            .await?;
        match found {
            Found::SoftLoggedOut(account, soft) => {
                let store_lock = account.sessions.store().lock().await?;
                let login = PasswordLogin {
                    device_display_name: login.device_display_name,
                    ..soft.password_login(login.password)
                };
                let session =
                    Session::login_password_locked(login, account.sessions(), store_lock).await?;
                Ok((account, session))
            }
            Found::Nobody => {
                let (account, store_lock) = self.fresh().await?;
                let login = PasswordLogin {
                    device_id: None,
                    ..login
                };
                match Session::login_password_locked(login, account.sessions(), store_lock).await {
                    Ok(session) => Ok((account, session)),
                    Err(error) => Err(self.abandon(&account, error).await),
                }
            }
        }
    }

    /// resumes the soft-logged-out account whose device `login` names, as
    /// `SoftLogout::oauth_login` sets it. without one it's a new account, since which account an
    /// OAuth login is for isn't known until it finishes
    pub async fn begin_oauth(
        &self,
        login: OAuthLogin,
    ) -> Result<(Account, PendingOAuthLogin), AccountError> {
        homeserver_input(&login.homeserver, login.allow_insecure_loopback)?;
        let device_id = login.device_id.clone();
        let found = self
            .find(|record| {
                record
                    .soft_logout()
                    .is_some_and(|soft| device_id.as_ref() == Some(&soft.device_id))
            })
            .await?;
        match found {
            Found::SoftLoggedOut(account, soft) => {
                let store_lock = account.sessions.store().lock().await?;
                let login = OAuthLogin {
                    homeserver: soft.homeserver,
                    client_id: login.client_id.or(soft.client_id),
                    allow_insecure_loopback: true,
                    ..login
                };
                let pending =
                    Session::begin_oauth_locked(login, account.sessions(), store_lock).await?;
                Ok((account, pending))
            }
            Found::Nobody => {
                let (account, store_lock) = self.fresh().await?;
                let login = OAuthLogin {
                    device_id: None,
                    ..login
                };
                match Session::begin_oauth_locked(login, account.sessions(), store_lock).await {
                    Ok(pending) => Ok((account, pending)),
                    Err(error) => Err(self.abandon(&account, error).await),
                }
            }
        }
    }

    /// a live login for the same person is refused rather than given a second device
    async fn find(&self, resumes: impl Fn(&SessionRecord) -> bool) -> Result<Found, AccountError> {
        for account in self.slots().await? {
            let Ok(Some(record)) = account.sessions.load().await else {
                continue;
            };
            if !resumes(&record) {
                continue;
            }
            return match record.soft_logout() {
                Some(soft) => Ok(Found::SoftLoggedOut(account, soft)),
                None => Err(AccountError::AlreadyLoggedIn(record.user_id().clone())),
            };
        }
        Ok(Found::Nobody)
    }

    /// locked before anything else can see it, so `list` never sweeps a login still under way
    async fn fresh(&self) -> Result<(Account, StoreLock), AccountError> {
        let account = self.open(TransactionId::new().to_string());
        let store_lock = account.sessions.store().lock().await?;
        #[cfg(feature = "indexeddb")]
        {
            let Root::Prefix(prefix) = &self.root;
            index::add(prefix, &account.id).await?;
        }
        Ok((account, store_lock))
    }

    /// a failed first login leaves nothing behind. one whose record didn't save has a live device
    /// on the server, so that stays for `UnsavedSession::save`
    async fn abandon(&self, account: &Account, error: AccountError) -> AccountError {
        if !matches!(error, AccountError::Unsaved { .. }) {
            self.sweep(account).await;
        }
        error
    }

    /// best effort, since whatever it leaves is found and swept again by the next `list`
    async fn sweep(&self, account: &Account) {
        let Ok(_store_lock) = account.sessions.store().lock().await else {
            return;
        };
        if !matches!(account.sessions.load().await, Ok(None)) {
            return;
        }
        if account.sessions.discard().await.is_err() {
            return;
        }
        #[cfg(feature = "indexeddb")]
        {
            let Root::Prefix(prefix) = &self.root;
            let _ = index::remove(prefix, &account.id).await;
        }
    }

    fn open(&self, id: String) -> Account {
        let sessions = match &self.root {
            #[cfg(feature = "sqlite")]
            Root::Directory(root) => EncryptedSessionStore::file(
                root.join(format!("{id}.session")),
                StoreConfig::sqlite(root.join(&id), self.passphrase.clone()),
            ),
            #[cfg(feature = "indexeddb")]
            Root::Prefix(prefix) => EncryptedSessionStore::indexeddb(StoreConfig::indexeddb(
                format!("{prefix}::{id}"),
                self.passphrase.clone(),
            )),
        };
        Account {
            id,
            sessions: Arc::new(sessions),
        }
    }

    async fn slots(&self) -> Result<Vec<Account>, AccountError> {
        let ids = match &self.root {
            #[cfg(feature = "sqlite")]
            Root::Directory(root) => directory_slots(root)?,
            #[cfg(feature = "indexeddb")]
            Root::Prefix(prefix) => index::list(prefix).await?,
        };
        Ok(ids.iter().filter_map(|id| self.account(id)).collect())
    }
}

/// a localpart or a full user id names the same account, but only on the same server. the server
/// is compared by name as well as by url, so a delegated `example.org` still finds the account
/// discovery took to `matrix.example.org`
fn record_names(record: &SessionRecord, homeserver: &str, username: &str) -> bool {
    let user_id = record.user_id();
    let username = username.trim();
    let user = if username.starts_with('@') {
        username.eq_ignore_ascii_case(user_id.as_str())
    } else {
        username.eq_ignore_ascii_case(user_id.localpart())
    };
    let typed = authority(homeserver);
    user && (typed.eq_ignore_ascii_case(user_id.server_name().as_str())
        || typed.eq_ignore_ascii_case(authority(record.homeserver())))
}

fn authority(homeserver: &str) -> &str {
    let homeserver = homeserver.trim();
    let rest = homeserver
        .split_once("://")
        .map_or(homeserver, |(_, rest)| rest);
    rest.split('/').next().unwrap_or(rest)
}

#[cfg(feature = "sqlite")]
fn directory_slots(root: &std::path::Path) -> Result<BTreeSet<String>, AccountError> {
    use std::io::ErrorKind;

    let entries = match std::fs::read_dir(root) {
        Ok(entries) => entries,
        Err(error) if error.kind() == ErrorKind::NotFound => return Ok(BTreeSet::new()),
        Err(error) => return Err(crate::account::account_error("listing the accounts", error)),
    };
    let mut ids = BTreeSet::new();
    for entry in entries {
        let entry =
            entry.map_err(|error| crate::account::account_error("listing the accounts", error))?;
        let name = entry.file_name();
        let Some(name) = name.to_str() else {
            continue;
        };
        if entry.path().is_dir() {
            ids.insert(name.to_owned());
        } else if let Some(id) = name.strip_suffix(".session") {
            ids.insert(id.to_owned());
        }
    }
    Ok(ids)
}

/// a key per account, so two tabs adding at once can't lose one to the other
#[cfg(feature = "indexeddb")]
mod index {
    use std::collections::BTreeSet;

    use indexed_db_futures::{
        Build,
        database::Database,
        error::{Error, OpenDbError},
        prelude::*,
        transaction::{Transaction, TransactionMode},
    };

    use crate::{AccountError, account::account_error};

    const ACCOUNTS: &str = "accounts";

    fn name(prefix: &str) -> String {
        format!("{prefix}::macltok-accounts")
    }

    async fn open(prefix: &str) -> Result<Database, OpenDbError> {
        Database::open(&name(prefix))
            .with_version(1u32)
            .with_on_upgrade_needed(|_, transaction: &Transaction<'_>| -> Result<(), Error> {
                transaction.db().create_object_store(ACCOUNTS).build()?;
                Ok(())
            })
            .build()?
            .await
    }

    pub(super) async fn list(prefix: &str) -> Result<BTreeSet<String>, AccountError> {
        let failed = |error| account_error("listing the accounts", error);
        let database = open(prefix).await.map_err(failed)?;
        let ids = keys(&database).await;
        database.close();
        ids.map_err(|error| account_error("listing the accounts", error))
    }

    pub(super) async fn add(prefix: &str, id: &str) -> Result<(), AccountError> {
        let failed = |error| account_error("adding the account", error);
        let database = open(prefix).await.map_err(failed)?;
        let added = write(&database, |store| {
            store.put(true).with_key(id).build()?;
            Ok(())
        })
        .await;
        database.close();
        added.map_err(|error| account_error("adding the account", error))
    }

    pub(super) async fn remove(prefix: &str, id: &str) -> Result<(), AccountError> {
        let failed = |error| account_error("removing the account", error);
        let database = open(prefix).await.map_err(failed)?;
        let removed = write(&database, |store| {
            store.delete(id).build()?;
            Ok(())
        })
        .await;
        database.close();
        removed.map_err(|error| account_error("removing the account", error))
    }

    async fn keys(database: &Database) -> Result<BTreeSet<String>, Error> {
        let transaction = database
            .transaction(ACCOUNTS)
            .with_mode(TransactionMode::Readonly)
            .build()?;
        let store = transaction.object_store(ACCOUNTS)?;
        store.get_all_keys::<String>().await?.collect()
    }

    async fn write(
        database: &Database,
        change: impl FnOnce(&indexed_db_futures::object_store::ObjectStore<'_>) -> Result<(), Error>,
    ) -> Result<(), Error> {
        let transaction = database
            .transaction(ACCOUNTS)
            .with_mode(TransactionMode::Readwrite)
            .build()?;
        change(&transaction.object_store(ACCOUNTS)?)?;
        transaction.commit().await
    }
}

1	use std::sync::Arc;
2	#[cfg(feature = "sqlite")]
3	use std::{collections::BTreeSet, path::PathBuf};
4
5	use ruma::TransactionId;
6
7	use crate::{
8	AccountError, EncryptedSessionStore, OAuthLogin, PasswordLogin, PendingOAuthLogin, Restore,
9	Session, SessionRecord, SessionStore, SoftLogout, StoreConfig, account::homeserver_input,
10	engine::StoreLock,
11	};
12
13	/// every account one owner has, a store each under one root and one passphrase. whoever holds
14	/// the set can resume any soft-logged-out device in it with just its password, and the device's
15	/// store has its e2ee keys, so a set belongs to one person and never to a whole machine
16	pub struct Accounts {
17	root: Root,
18	passphrase: String,
19	}
20
21	enum Root {
22	#[cfg(feature = "sqlite")]
23	Directory(PathBuf),
24	#[cfg(feature = "indexeddb")]
25	Prefix(String),
26	}
27
28	/// one account's record and store
29	#[derive(Clone)]
30	pub struct Account {
31	id: String,
32	sessions: Arc<EncryptedSessionStore>,
33	}
34
35	impl Account {
36	/// stable for the account's life, and safe in a cookie or a url
37	#[must_use]
38	pub fn id(&self) -> &str {
39	&self.id
40	}
41
42	/// for `Termination::retain`. a discarded account drops out of `Accounts::list`
43	#[must_use]
44	pub fn sessions(&self) -> Arc<dyn SessionStore> {
45	self.sessions.clone()
46	}
47
48	pub async fn restore(&self) -> Result<Option<Restore>, AccountError> {
49	Session::restore(self.sessions()).await
50	}
51	}
52
53	impl std::fmt::Debug for Account {
54	fn fmt(&self, formatter: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
55	formatter
56	.debug_struct("Account")
57	.field("id", &self.id)
58	.finish_non_exhaustive()
59	}
60	}
61
62	enum Found {
63	Nobody,
64	SoftLoggedOut(Account, SoftLogout),
65	}
66
67	impl Accounts {
68	/// each account is a store directory under `root` with its record beside it
69	#[cfg(feature = "sqlite")]
70	#[must_use]
71	pub fn sqlite(root: impl Into<PathBuf>, passphrase: impl Into<String>) -> Self {
72	Self {
73	root: Root::Directory(root.into()),
74	passphrase: passphrase.into(),
75	}
76	}
77
78	/// each account is a store named `<prefix>::<id>`, listed in `<prefix>::macltok-accounts`
79	#[cfg(feature = "indexeddb")]
80	#[must_use]
81	pub fn indexeddb(prefix: impl Into<String>, passphrase: impl Into<String>) -> Self {
82	Self {
83	root: Root::Prefix(prefix.into()),
84	passphrase: passphrase.into(),
85	}
86	}
87
88	/// `None` for anything `Account::id` couldn't have been
89	#[must_use]
90	pub fn account(&self, id: &str) -> Option<Account> {
91	let valid =
92	!id.is_empty() && id.len() <= 64 && id.bytes().all(\|b\| b.is_ascii_alphanumeric());
93	valid.then(\|\| self.open(id.to_owned()))
94	}
95
96	/// every account with a record. a store left without one, by a login that died halfway or a
97	/// discard that couldn't finish, is deleted on the way past
98	pub async fn list(&self) -> Result<Vec<Account>, AccountError> {
99	let mut accounts = Vec::new();
100	for account in self.slots().await? {
101	match account.sessions.load().await {
102	Ok(None) => self.sweep(&account).await,
103	Ok(Some(_)) \| Err(_) => accounts.push(account),
104	}
105	}
106	Ok(accounts)
107	}
108
109	/// a soft-logged-out account the login names is resumed as its own device, keeping its keys.
110	/// anyone else gets a new account
111	pub async fn login_password(
112	&self,
113	login: PasswordLogin,
114	) -> Result<(Account, Session), AccountError> {
115	homeserver_input(&login.homeserver, login.allow_insecure_loopback)?;
116	let found = self
117	.find(\|record\| record_names(record, &login.homeserver, &login.username))
118	.await?;
119	match found {
120	Found::SoftLoggedOut(account, soft) => {
121	let store_lock = account.sessions.store().lock().await?;
122	let login = PasswordLogin {
123	device_display_name: login.device_display_name,
124	..soft.password_login(login.password)
125	};
126	let session =
127	Session::login_password_locked(login, account.sessions(), store_lock).await?;
128	Ok((account, session))
129	}
130	Found::Nobody => {
131	let (account, store_lock) = self.fresh().await?;
132	let login = PasswordLogin {
133	device_id: None,
134	..login
135	};
136	match Session::login_password_locked(login, account.sessions(), store_lock).await {
137	Ok(session) => Ok((account, session)),
138	Err(error) => Err(self.abandon(&account, error).await),
139	}
140	}
141	}
142	}
143
144	/// resumes the soft-logged-out account whose device `login` names, as
145	/// `SoftLogout::oauth_login` sets it. without one it's a new account, since which account an
146	/// OAuth login is for isn't known until it finishes
147	pub async fn begin_oauth(
148	&self,
149	login: OAuthLogin,
150	) -> Result<(Account, PendingOAuthLogin), AccountError> {
151	homeserver_input(&login.homeserver, login.allow_insecure_loopback)?;
152	let device_id = login.device_id.clone();
153	let found = self
154	.find(\|record\| {
155	record
156	.soft_logout()
157	.is_some_and(\|soft\| device_id.as_ref() == Some(&soft.device_id))
158	})
159	.await?;
160	match found {
161	Found::SoftLoggedOut(account, soft) => {
162	let store_lock = account.sessions.store().lock().await?;
163	let login = OAuthLogin {
164	homeserver: soft.homeserver,
165	client_id: login.client_id.or(soft.client_id),
166	allow_insecure_loopback: true,
167	..login
168	};
169	let pending =
170	Session::begin_oauth_locked(login, account.sessions(), store_lock).await?;
171	Ok((account, pending))
172	}
173	Found::Nobody => {
174	let (account, store_lock) = self.fresh().await?;
175	let login = OAuthLogin {
176	device_id: None,
177	..login
178	};
179	match Session::begin_oauth_locked(login, account.sessions(), store_lock).await {
180	Ok(pending) => Ok((account, pending)),
181	Err(error) => Err(self.abandon(&account, error).await),
182	}
183	}
184	}
185	}
186
187	/// a live login for the same person is refused rather than given a second device
188	async fn find(&self, resumes: impl Fn(&SessionRecord) -> bool) -> Result<Found, AccountError> {
189	for account in self.slots().await? {
190	let Ok(Some(record)) = account.sessions.load().await else {
191	continue;
192	};
193	if !resumes(&record) {
194	continue;
195	}
196	return match record.soft_logout() {
197	Some(soft) => Ok(Found::SoftLoggedOut(account, soft)),
198	None => Err(AccountError::AlreadyLoggedIn(record.user_id().clone())),
199	};
200	}
201	Ok(Found::Nobody)
202	}
203
204	/// locked before anything else can see it, so `list` never sweeps a login still under way
205	async fn fresh(&self) -> Result<(Account, StoreLock), AccountError> {
206	let account = self.open(TransactionId::new().to_string());
207	let store_lock = account.sessions.store().lock().await?;
208	#[cfg(feature = "indexeddb")]
209	{
210	let Root::Prefix(prefix) = &self.root;
211	index::add(prefix, &account.id).await?;
212	}
213	Ok((account, store_lock))
214	}
215
216	/// a failed first login leaves nothing behind. one whose record didn't save has a live device
217	/// on the server, so that stays for `UnsavedSession::save`
218	async fn abandon(&self, account: &Account, error: AccountError) -> AccountError {
219	if !matches!(error, AccountError::Unsaved { .. }) {
220	self.sweep(account).await;
221	}
222	error
223	}
224
225	/// best effort, since whatever it leaves is found and swept again by the next `list`
226	async fn sweep(&self, account: &Account) {
227	let Ok(_store_lock) = account.sessions.store().lock().await else {
228	return;
229	};
230	if !matches!(account.sessions.load().await, Ok(None)) {
231	return;
232	}
233	if account.sessions.discard().await.is_err() {
234	return;
235	}
236	#[cfg(feature = "indexeddb")]
237	{
238	let Root::Prefix(prefix) = &self.root;
239	let _ = index::remove(prefix, &account.id).await;
240	}
241	}
242
243	fn open(&self, id: String) -> Account {
244	let sessions = match &self.root {
245	#[cfg(feature = "sqlite")]
246	Root::Directory(root) => EncryptedSessionStore::file(
247	root.join(format!("{id}.session")),
248	StoreConfig::sqlite(root.join(&id), self.passphrase.clone()),
249	),
250	#[cfg(feature = "indexeddb")]
251	Root::Prefix(prefix) => EncryptedSessionStore::indexeddb(StoreConfig::indexeddb(
252	format!("{prefix}::{id}"),
253	self.passphrase.clone(),
254	)),
255	};
256	Account {
257	id,
258	sessions: Arc::new(sessions),
259	}
260	}
261
262	async fn slots(&self) -> Result<Vec<Account>, AccountError> {
263	let ids = match &self.root {
264	#[cfg(feature = "sqlite")]
265	Root::Directory(root) => directory_slots(root)?,
266	#[cfg(feature = "indexeddb")]
267	Root::Prefix(prefix) => index::list(prefix).await?,
268	};
269	Ok(ids.iter().filter_map(\|id\| self.account(id)).collect())
270	}
271	}
272
273	/// a localpart or a full user id names the same account, but only on the same server. the server
274	/// is compared by name as well as by url, so a delegated `example.org` still finds the account
275	/// discovery took to `matrix.example.org`
276	fn record_names(record: &SessionRecord, homeserver: &str, username: &str) -> bool {
277	let user_id = record.user_id();
278	let username = username.trim();
279	let user = if username.starts_with('@') {
280	username.eq_ignore_ascii_case(user_id.as_str())
281	} else {
282	username.eq_ignore_ascii_case(user_id.localpart())
283	};
284	let typed = authority(homeserver);
285	user && (typed.eq_ignore_ascii_case(user_id.server_name().as_str())
286	\|\| typed.eq_ignore_ascii_case(authority(record.homeserver())))
287	}
288
289	fn authority(homeserver: &str) -> &str {
290	let homeserver = homeserver.trim();
291	let rest = homeserver
292	.split_once("://")
293	.map_or(homeserver, \|(_, rest)\| rest);
294	rest.split('/').next().unwrap_or(rest)
295	}
296
297	#[cfg(feature = "sqlite")]
298	fn directory_slots(root: &std::path::Path) -> Result<BTreeSet<String>, AccountError> {
299	use std::io::ErrorKind;
300
301	let entries = match std::fs::read_dir(root) {
302	Ok(entries) => entries,
303	Err(error) if error.kind() == ErrorKind::NotFound => return Ok(BTreeSet::new()),
304	Err(error) => return Err(crate::account::account_error("listing the accounts", error)),
305	};
306	let mut ids = BTreeSet::new();
307	for entry in entries {
308	let entry =
309	entry.map_err(\|error\| crate::account::account_error("listing the accounts", error))?;
310	let name = entry.file_name();
311	let Some(name) = name.to_str() else {
312	continue;
313	};
314	if entry.path().is_dir() {
315	ids.insert(name.to_owned());
316	} else if let Some(id) = name.strip_suffix(".session") {
317	ids.insert(id.to_owned());
318	}
319	}
320	Ok(ids)
321	}
322
323	/// a key per account, so two tabs adding at once can't lose one to the other
324	#[cfg(feature = "indexeddb")]
325	mod index {
326	use std::collections::BTreeSet;
327
328	use indexed_db_futures::{
329	Build,
330	database::Database,
331	error::{Error, OpenDbError},
332	prelude::*,
333	transaction::{Transaction, TransactionMode},
334	};
335
336	use crate::{AccountError, account::account_error};
337
338	const ACCOUNTS: &str = "accounts";
339
340	fn name(prefix: &str) -> String {
341	format!("{prefix}::macltok-accounts")
342	}
343
344	async fn open(prefix: &str) -> Result<Database, OpenDbError> {
345	Database::open(&name(prefix))
346	.with_version(1u32)
347	.with_on_upgrade_needed(\|_, transaction: &Transaction<'_>\| -> Result<(), Error> {
348	transaction.db().create_object_store(ACCOUNTS).build()?;
349	Ok(())
350	})
351	.build()?
352	.await
353	}
354
355	pub(super) async fn list(prefix: &str) -> Result<BTreeSet<String>, AccountError> {
356	let failed = \|error\| account_error("listing the accounts", error);
357	let database = open(prefix).await.map_err(failed)?;
358	let ids = keys(&database).await;
359	database.close();
360	ids.map_err(\|error\| account_error("listing the accounts", error))
361	}
362
363	pub(super) async fn add(prefix: &str, id: &str) -> Result<(), AccountError> {
364	let failed = \|error\| account_error("adding the account", error);
365	let database = open(prefix).await.map_err(failed)?;
366	let added = write(&database, \|store\| {
367	store.put(true).with_key(id).build()?;
368	Ok(())
369	})
370	.await;
371	database.close();
372	added.map_err(\|error\| account_error("adding the account", error))
373	}
374
375	pub(super) async fn remove(prefix: &str, id: &str) -> Result<(), AccountError> {
376	let failed = \|error\| account_error("removing the account", error);
377	let database = open(prefix).await.map_err(failed)?;
378	let removed = write(&database, \|store\| {
379	store.delete(id).build()?;
380	Ok(())
381	})
382	.await;
383	database.close();
384	removed.map_err(\|error\| account_error("removing the account", error))
385	}
386
387	async fn keys(database: &Database) -> Result<BTreeSet<String>, Error> {
388	let transaction = database
389	.transaction(ACCOUNTS)
390	.with_mode(TransactionMode::Readonly)
391	.build()?;
392	let store = transaction.object_store(ACCOUNTS)?;
393	store.get_all_keys::<String>().await?.collect()
394	}
395
396	async fn write(
397	database: &Database,
398	change: impl FnOnce(&indexed_db_futures::object_store::ObjectStore<'_>) -> Result<(), Error>,
399	) -> Result<(), Error> {
400	let transaction = database
401	.transaction(ACCOUNTS)
402	.with_mode(TransactionMode::Readwrite)
403	.build()?;
404	change(&transaction.object_store(ACCOUNTS)?)?;
405	transaction.commit().await
406	}
407	}