Auth bindings (#58)

* basic framework. still has errors

* added functionality for main endpoints + some structuring

* formatting

* unused code

* mimicked CLI function with wait_for process

* added basic auth bindings

* made PR changes, added playground

* cargo fmt

* removed missed println

* misc tests fixes

* cargo fmt

* added windows support

* cargo fmt

* all OS use dunce

* restructured profile slightly; fixed mac bug

* profile changes, new main.rs

* fixed requested pr + canonicaliation bug

* fixed regressed bug in ui

* fixed regressed bugs

* fixed git error

* typo

* ran prettier

* clippy

* playground clippy

* ported profile loading fix

* profile change for real, url println and clippy

* PR changes

* auth bindings + semisynch flow

* fixed dropping task error

* prettier, eslint, clippy

* removed debugging modifications

* removed unused function that eslinter missed :(

* fixed settings not being released

---------

Co-authored-by: Wyatt <wyatt@modrinth.com>

theseus/src/state/auth_task.rs

@@ -0,0 +1,74 @@
+use crate::launcher::auth::Credentials;
+use std::mem;
+use tokio::task::JoinHandle;
+
+// Authentication task
+// A wrapper over the authentication task that allows it to be called from the frontend
+// without caching the task handle in the frontend
+
+pub struct AuthTask(Option<JoinHandle<crate::Result<Credentials>>>);
+
+impl AuthTask {
+    pub fn new() -> AuthTask {
+        AuthTask(None)
+    }
+
+    pub async fn begin_auth(&mut self) -> crate::Result<url::Url> {
+        // Creates a channel to receive the URL
+        let (tx, rx) = tokio::sync::oneshot::channel::<url::Url>();
+        let task = tokio::spawn(crate::auth::authenticate(tx));
+
+        // If receiver is dropped, try to get Hydra error
+        let url = rx.await;
+        let url = match url {
+            Ok(url) => url,
+            Err(e) => {
+                task.await??;
+                return Err(e.into()); // truly a dropped receiver
+            }
+        };
+
+        // Flow is going, store in state and return
+        self.0 = Some(task);
+
+        Ok(url)
+    }
+
+    pub async fn await_auth_completion(
+        &mut self,
+    ) -> crate::Result<Credentials> {
+        // Gets the task handle from the state, replacing with None
+        let task = mem::replace(&mut self.0, None);
+
+        // Waits for the task to complete, and returns the credentials
+        let credentials = task
+            .ok_or_else(|| AuthTaskError::TaskMissing)?
+            .await
+            .map_err(AuthTaskError::from)??;
+
+        Ok(credentials)
+    }
+
+    pub async fn cancel(&mut self) {
+        // Gets the task handle from the state, replacing with None
+        let task = mem::replace(&mut self.0, None);
+        if let Some(task) = task {
+            // Cancels the task
+            task.abort();
+        }
+    }
+}
+
+impl Default for AuthTask {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+#[derive(thiserror::Error, Debug)]
+pub enum AuthTaskError {
+    #[error("Authentication task was aborted or missing")]
+    TaskMissing,
+    #[error("Join handle error")]
+    JoinHandleError(#[from] tokio::task::JoinError),
+}

theseus/src/state/mod.rs

@@ -25,6 +25,9 @@ pub use self::users::*;
 mod children;
 pub use self::children::*;
 
+mod auth_task;
+pub use self::auth_task::*;
+
 // Global state
 static LAUNCHER_STATE: OnceCell<Arc<State>> = OnceCell::const_new();
 pub struct State {
@@ -39,8 +42,10 @@ pub struct State {
     // TODO: settings API
     /// Launcher configuration
     pub settings: RwLock<Settings>,
-    /// Reference to process children
+    /// Reference to minecraft process children
     pub children: RwLock<Children>,
+    /// Authentication flow
+    pub auth_flow: RwLock<AuthTask>,
     /// Launcher profile metadata
     pub(crate) profiles: RwLock<Profiles>,
     /// Launcher user account info
@@ -80,6 +85,8 @@ impl State {
 
                     let children = Children::new();
 
+                    let auth_flow = AuthTask::new();
+
                     Ok(Arc::new(Self {
                         database,
                         directories,
@@ -89,6 +96,7 @@ impl State {
                         profiles: RwLock::new(profiles),
                         users: RwLock::new(users),
                         children: RwLock::new(children),
+                        auth_flow: RwLock::new(auth_flow),
                     }))
                 }
             })