macltok

#[cfg(feature = "sqlite")]

use std::path::PathBuf;

#[cfg(not(target_family = "wasm"))]

use std::sync::atomic::{AtomicBool, Ordering};

use std::{collections::HashMap, sync::Arc};

use matrix_sdk::{

    Client, ClientBuilder, SendOutsideWasm, SessionChange, SessionMeta, SyncOutsideWasm,

    ThreadingSupport,

    authentication::{

        AuthSession,

        matrix::MatrixSession,

        oauth::{

            ClientId, ClientRegistrationData, CsrfToken, OAuthSession, UserSession,

            registration::{ApplicationType, ClientMetadata, Localized, OAuthGrantType},

        },

    },

    cross_process_lock::CrossProcessLockConfig,

    encryption::{BackupDownloadStrategy, EncryptionSettings},

    ruma::{OwnedDeviceId, OwnedUserId, serde::Raw},

};

use serde::{Deserialize, Serialize};

use thiserror::Error;

use tokio::sync::{broadcast, mpsc};

use url::Url;

use crate::{

    ClientHandle, Engine, EngineConfig, EngineError, ErrorKind, EventStream, SessionStore,

    engine::{Persistence, StoreLock},

    error::SourceError,

};

/// a logged in client and the `SessionStore` its record lives in. the engine it builds

/// saves every token rotation there, unless told `without_persistence`

pub struct Session {

    client: Client,

    tracking: Tracking,

    store_lock: StoreLock,

}

/// taken as soon as the client exists, since the sdk can refresh before there's an engine

struct Tracking {

    session_changes: broadcast::Receiver<SessionChange>,

    persistence: Option<Persistence>,

    #[cfg(not(target_family = "wasm"))]

    inline: Arc<AtomicBool>,

}

#[non_exhaustive]

pub struct PasswordLogin {

    pub homeserver: String,

    pub username: String,

    pub password: String,

    pub device_display_name: Option<String>,

    /// set after a soft logout so the store's keys still belong to us

    pub device_id: Option<OwnedDeviceId>,

}

impl PasswordLogin {

    #[must_use]

    pub fn new(

        homeserver: impl Into<String>,

        username: impl Into<String>,

        password: impl Into<String>,

    ) -> Self {

        Self {

            homeserver: homeserver.into(),

            username: username.into(),

            password: password.into(),

            device_display_name: None,

            device_id: None,

        }

    }

    #[must_use]

    pub fn with_device_display_name(mut self, name: impl Into<String>) -> Self {

        self.device_display_name = Some(name.into());

        self

    }

    #[must_use]

    pub fn with_device_id(mut self, device_id: OwnedDeviceId) -> Self {

        self.device_id = Some(device_id);

        self

    }

}

#[non_exhaustive]

pub struct OAuthLogin {

    pub homeserver: String,

    pub redirect_uri: String,

    pub client_uri: String,

    pub client_name: Option<String>,

    pub client_id: Option<String>,

    pub device_id: Option<OwnedDeviceId>,

    pub application_type: OAuthApplicationType,

}

impl OAuthLogin {

    #[must_use]

    pub fn new(

        homeserver: impl Into<String>,

        redirect_uri: impl Into<String>,

        client_uri: impl Into<String>,

        application_type: OAuthApplicationType,

    ) -> Self {

        Self {

            homeserver: homeserver.into(),

            redirect_uri: redirect_uri.into(),

            client_uri: client_uri.into(),

            client_name: None,

            client_id: None,

            device_id: None,

            application_type,

        }

    }

    #[must_use]

    pub fn with_client_name(mut self, name: impl Into<String>) -> Self {

        self.client_name = Some(name.into());

        self

    }

    /// a statically registered client id, skipping dynamic registration

    #[must_use]

    pub fn with_client_id(mut self, client_id: impl Into<String>) -> Self {

        self.client_id = Some(client_id.into());

        self

    }

    #[must_use]

    pub fn with_device_id(mut self, device_id: OwnedDeviceId) -> Self {

        self.device_id = Some(device_id);

        self

    }

}

#[derive(Clone, Copy, Debug, Eq, PartialEq)]

#[non_exhaustive]

pub enum OAuthApplicationType {

    Native,

    Web,

}

pub struct PendingOAuthLogin {

    client: Client,

    sessions: Arc<dyn SessionStore>,

    tracking: Option<(Tracking, StoreLock)>,

    authorization_url: String,

    state: Option<CsrfToken>,

}

impl PendingOAuthLogin {

    #[must_use]

    pub fn authorization_url(&self) -> &str {

        &self.authorization_url

    }

    #[must_use]

    pub fn registered_client_id(&self) -> String {

        self.client

            .oauth()

            .client_id()

            .expect("OAuth client was registered before authorization")

            .as_str()

            .to_owned()

    }

    #[must_use]

    pub const fn is_pending(&self) -> bool {

        self.state.is_some()

    }

    pub async fn finish(&mut self, callback_url: &str) -> Result<Session, AccountError> {

        let callback_url = Url::parse(callback_url)

            .map_err(|error| account_error("parsing the OAuth callback URL", error))?;

        let state = self

            .state

            .take()

            .ok_or(AccountError::OAuthCallbackAlreadySubmitted)?;

        let oauth = self.client.oauth();

        if let Err(error) = oauth.finish_login(callback_url.into()).await {

            oauth.abort_login(&state).await;

            return Err(account_error("OAuth login", error));

        }

        let (tracking, store_lock) = self

            .tracking

            .take()

            .ok_or(AccountError::OAuthCallbackAlreadySubmitted)?;

        Session::saved(

            self.client.clone(),

            self.sessions.clone(),

            tracking,

            store_lock,

        )

        .await

    }

    pub async fn abort(mut self) {

        if let Some(state) = self.state.take() {

            self.client.oauth().abort_login(&state).await;

        }

    }

}

pub struct StoreConfig {

    location: StoreLocation,

    passphrase: String,

}

enum StoreLocation {

    #[cfg(feature = "sqlite")]

    Sqlite(PathBuf),

    #[cfg(feature = "indexeddb")]

    IndexedDb(String),

}

impl StoreConfig {

    #[cfg(feature = "sqlite")]

    #[must_use]

    pub fn sqlite(path: impl Into<PathBuf>, passphrase: impl Into<String>) -> Self {

        Self {

            location: StoreLocation::Sqlite(path.into()),

            passphrase: passphrase.into(),

        }

    }

    #[cfg(feature = "indexeddb")]

    #[must_use]

    pub fn indexeddb(name: impl Into<String>, passphrase: impl Into<String>) -> Self {

        Self {

            location: StoreLocation::IndexedDb(name.into()),

            passphrase: passphrase.into(),

        }

    }

    /// delete the store's databases, once nothing has them open

    pub async fn delete(&self) -> Result<(), AccountError> {

        match &self.location {

            #[cfg(feature = "sqlite")]

            StoreLocation::Sqlite(path) => crate::session_store::delete_sqlite_store(path)

                .map_err(|error| account_error("deleting the Matrix store", error)),

            #[cfg(feature = "indexeddb")]

            StoreLocation::IndexedDb(name) => crate::session_store::delete_indexeddb_store(name)

                .await

                .map_err(|error| error.into_account_error("deleting the Matrix store")),

        }

    }

    /// taken before the client opens the store, and held until the engine and every

    /// `ClientHandle` are gone

    pub(crate) async fn lock(&self) -> Result<StoreLock, AccountError> {

        match &self.location {

            #[cfg(feature = "sqlite")]

            StoreLocation::Sqlite(path) => StoreLock::file(path),

            #[cfg(feature = "indexeddb")]

            StoreLocation::IndexedDb(name) => StoreLock::web(name).await,

        }

    }

    pub(crate) fn passphrase(&self) -> &str {

        &self.passphrase

    }

    #[cfg(feature = "indexeddb")]

    pub(crate) fn indexeddb_name(&self) -> &str {

        let StoreLocation::IndexedDb(name) = &self.location;

        name

    }

}

/// Serializable authentication secrets. A `SessionStore` keeps it, and the engine

/// replaces it there on every token rotation.

#[derive(Clone, Deserialize, Serialize)]

pub struct SessionRecord {

    homeserver: String,

    authentication: AuthenticationRecord,

}

#[derive(Clone, Deserialize, Serialize)]

#[serde(tag = "type", content = "session", rename_all = "snake_case")]

enum AuthenticationRecord {

    Matrix(MatrixSession),

    OAuth {

        client_id: ClientId,

        user: UserSession,

    },

    SoftLoggedOut {

        meta: SessionMeta,

        client_id: Option<ClientId>,

    },

}

impl SessionRecord {

    #[must_use]

    pub fn homeserver(&self) -> &str {

        &self.homeserver

    }

    pub(crate) fn soft_logged_out(self) -> Self {

        let authentication = match self.authentication {

            AuthenticationRecord::Matrix(session) => AuthenticationRecord::SoftLoggedOut {

                meta: session.meta,

                client_id: None,

            },

            AuthenticationRecord::OAuth { client_id, user } => {

                AuthenticationRecord::SoftLoggedOut {

                    meta: user.meta,

                    client_id: Some(client_id),

                }

            }

            soft @ AuthenticationRecord::SoftLoggedOut { .. } => soft,

        };

        Self {

            homeserver: self.homeserver,

            authentication,

        }

    }

}

pub enum Restore {

    Resumed(Session),

    SoftLoggedOut(SoftLogout),

}

/// who to log in again as. the store keeps this device's e2ee keys, so a login

/// as any other device would orphan them

#[derive(Clone, Debug)]

#[non_exhaustive]

pub struct SoftLogout {

    pub homeserver: String,

    pub user_id: OwnedUserId,

    pub device_id: OwnedDeviceId,

    /// set when the login was OAuth, for `OAuthLogin::with_client_id`

    pub client_id: Option<String>,

}

impl SoftLogout {

    #[must_use]

    pub fn password_login(&self, password: impl Into<String>) -> PasswordLogin {

        PasswordLogin::new(self.homeserver.clone(), self.user_id.as_str(), password)

            .with_device_id(self.device_id.clone())

    }

}

#[derive(Debug, Error)]

pub enum AccountError {

    #[error("{context} failed")]

    Operation {

        context: &'static str,

        #[source]

        source: Box<SourceError>,

    },

    #[error("the homeserver returned no authenticated session")]

    MissingSession,

    #[error("the SDK returned an unsupported authentication session")]

    UnsupportedAuthentication,

    #[error("the OAuth callback was already submitted")]

    OAuthCallbackAlreadySubmitted,

    /// an IndexedDB delete is waiting on the store's other connections. it goes through

    /// once they close, and opening the store again waits behind it

    #[error("the store is still open elsewhere, it will be deleted once that closes")]

    StoreDeletePending,

    /// another engine, in this process or another, has the store. only one runs per store

    #[error("another engine is using this store")]

    StoreInUse,

    /// the login worked but its first record didn't save. the server already has the

    /// device, so retry the save rather than log in again

    #[error("saving the new login's record failed")]

    Unsaved {

        session: Box<UnsavedSession>,

        #[source]

        source: Box<AccountError>,

    },

    #[error(transparent)]

    Engine(#[from] EngineError),

}

/// a live login whose record never reached its `SessionStore`

pub struct UnsavedSession {

    session: Session,

    sessions: Arc<dyn SessionStore>,

}

impl UnsavedSession {

    pub async fn save(self) -> Result<Session, AccountError> {

        let saved = match session_record(&self.session.client) {

            Ok(record) => self.sessions.save(&record).await,

            Err(error) => Err(error),

        };

        match saved {

            Ok(()) => Ok(self.session),

            Err(source) => Err(AccountError::Unsaved {

                session: Box::new(self),

                source: Box::new(source),

            }),

        }

    }

    /// the record to keep somewhere else, if the store won't take it

    pub fn record(&self) -> Result<SessionRecord, AccountError> {

        session_record(&self.session.client)

    }

}

impl std::fmt::Debug for UnsavedSession {

    fn fmt(&self, formatter: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {

        formatter

            .debug_struct("UnsavedSession")

            .finish_non_exhaustive()

    }

}

impl Session {

    pub async fn login_password(

        login: PasswordLogin,

        sessions: Arc<dyn SessionStore>,

    ) -> Result<Self, AccountError> {

        let store_lock = sessions.store().lock().await?;

        let client = matrix_client_builder(sessions.store())

            .server_name_or_homeserver_url(login.homeserver.trim())

            .build()

            .await

            .map_err(|error| account_error("building the Matrix client", error))?;

        let tracking = Tracking::start(&client, sessions.clone())?;

        let mut request = client

            .matrix_auth()

            .login_username(login.username.trim(), &login.password)

            .request_refresh_token();

        if let Some(name) = login.device_display_name.as_deref() {

            request = request.initial_device_display_name(name);

        }

        if let Some(device_id) = login.device_id.as_deref() {

            request = request.device_id(device_id.as_str());

        }

        request

            .send()

            .await

            .map_err(|error| account_error("password login", error))?;

        Self::saved(client, sessions, tracking, store_lock).await

    }

    /// the pending login lives only in this process, so the one that begins it has to finish it

    pub async fn begin_oauth(

        login: OAuthLogin,

        sessions: Arc<dyn SessionStore>,

    ) -> Result<PendingOAuthLogin, AccountError> {

        let redirect_uri = Url::parse(login.redirect_uri.trim())

            .map_err(|error| account_error("parsing the OAuth redirect URI", error))?;

        let client_uri = Url::parse(login.client_uri.trim())

            .map_err(|error| account_error("parsing the OAuth client URI", error))?;

        let store_lock = sessions.store().lock().await?;

        let client = matrix_client_builder(sessions.store())

            .server_name_or_homeserver_url(login.homeserver.trim())

            .build()

            .await

            .map_err(|error| account_error("building the Matrix client", error))?;

        let tracking = Tracking::start(&client, sessions.clone())?;

        let application_type = match login.application_type {

            OAuthApplicationType::Native => ApplicationType::Native,

            OAuthApplicationType::Web => ApplicationType::Web,

        };

        let mut metadata = ClientMetadata::new(

            application_type,

            vec![OAuthGrantType::AuthorizationCode {

                redirect_uris: vec![redirect_uri.clone()],

            }],

            Localized::new(client_uri, []),

        );

        metadata.client_name = login.client_name.map(|name| Localized::new(name, []));

        let metadata = Raw::new(&metadata)

            .map_err(|error| account_error("serializing OAuth client metadata", error))?;

        let mut registration = ClientRegistrationData::new(metadata);

        if let Some(client_id) = login.client_id {

            registration.static_registrations = Some(HashMap::from([(

                client.homeserver(),

                ClientId::new(client_id),

            )]));

        }

        let authorization = client

            .oauth()

            .login(redirect_uri, login.device_id, Some(registration), None)

            .build()

            .await

            .map_err(|error| account_error("starting OAuth login", error))?;