feat: add hooks for session

src/flutter.rs

@@ -1,4 +1,5 @@
 use crate::{
+    api::SessionHook,
     client::*,
     flutter_ffi::EventToUI,
     ui_session_interface::{io_loop, InvokeUiSession, Session},
@@ -40,9 +41,9 @@ pub(super) const APP_TYPE_DESKTOP_FILE_TRANSFER: &str = "file transfer";
 pub(super) const APP_TYPE_DESKTOP_PORT_FORWARD: &str = "port forward";
 
 lazy_static::lazy_static! {
-    pub static ref CUR_SESSION_ID: RwLock<String> = Default::default();
-    pub static ref SESSIONS: RwLock<HashMap<String, Session<FlutterHandler>>> = Default::default();
-    pub static ref GLOBAL_EVENT_STREAM: RwLock<HashMap<String, StreamSink<String>>> = Default::default(); // rust to dart event channel
+    pub(crate) static ref CUR_SESSION_ID: RwLock<String> = Default::default();
+    pub(crate) static ref SESSIONS: RwLock<HashMap<String, Session<FlutterHandler>>> = Default::default();
+    pub(crate) static ref GLOBAL_EVENT_STREAM: RwLock<HashMap<String, StreamSink<String>>> = Default::default(); // rust to dart event channel
 }
 
 #[cfg(all(target_os = "windows", feature = "flutter_texture_render"))]
@@ -146,6 +147,7 @@ pub struct FlutterHandler {
     notify_rendered: Arc<RwLock<bool>>,
     renderer: Arc<RwLock<VideoRenderer>>,
     peer_info: Arc<RwLock<PeerInfo>>,
+    hooks: Arc<RwLock<HashMap<String, SessionHook>>>,
 }
 
 #[cfg(not(feature = "flutter_texture_render"))]
@@ -157,6 +159,7 @@ pub struct FlutterHandler {
     pub rgba: Arc<RwLock<Vec<u8>>>,
     pub rgba_valid: Arc<AtomicBool>,
     peer_info: Arc<RwLock<PeerInfo>>,
+    hooks: Arc<RwLock<HashMap<String, SessionHook>>>,
 }
 
 #[cfg(feature = "flutter_texture_render")]
@@ -255,7 +258,7 @@ impl FlutterHandler {
         }
     }
 
-    pub fn close_event_stream(&mut self) {
+    pub(crate) fn close_event_stream(&mut self) {
         let mut stream_lock = self.event_stream.write().unwrap();
         if let Some(stream) = &*stream_lock {
             stream.add(EventToUI::Event("close".to_owned()));
@@ -277,6 +280,26 @@ impl FlutterHandler {
         serde_json::ser::to_string(&msg_vec).unwrap_or("".to_owned())
     }
 
+    pub(crate) fn add_session_hook(&self, key: String, hook: crate::api::SessionHook) -> bool {
+        let mut hooks = self.hooks.write().unwrap();
+        if hooks.contains_key(&key) {
+            // Already has the hook with this key.
+            return false;
+        }
+        let _ = hooks.insert(key, hook);
+        true
+    }
+
+    pub(crate) fn remove_session_hook(&self, key: &String) -> bool {
+        let mut hooks = self.hooks.write().unwrap();
+        if !hooks.contains_key(key) {
+            // The hook with this key does not found.
+            return false;
+        }
+        let _ = hooks.remove(key);
+        true
+    }
+
     #[inline]
     #[cfg(feature = "flutter_texture_render")]
     pub fn register_texture(&mut self, ptr: usize) {