add vec2sgl projection

src/projection/mod.rs

@@ -3,6 +3,7 @@ pub mod projection_helper;
 
 pub mod sgl2idx;
 pub mod sgl2seq;
+pub mod vec2sgl;
 pub mod vec2seq;
 pub mod vec2bin;
 pub mod vec2json;

src/projection/vec2sgl.rs

@@ -0,0 +1,85 @@
+use {
+    crate::{
+        view::{
+            InnerViewPort, Observer, ObserverBroadcast, ObserverExt, OuterViewPort, View, ViewPort,
+            sequence::SequenceView,
+            singleton::SingletonView
+        },
+        buffer::vec::VecDiff,
+    },
+    std::sync::Arc,
+    std::sync::RwLock,
+};
+
+//<<<<>>>><<>><><<>><<<*>>><<>><><<>><<<<>>>>
+
+/// Adapter View implementing `Singleton` for `Vec`
+pub struct VecSingleton<T>
+where
+    T: Clone + Send + Sync + 'static,
+{
+    data: Option<Arc<RwLock<Vec<T>>>>,
+    cast: Arc<RwLock<ObserverBroadcast<dyn SingletonView<Item = Vec<T>>>>>,
+}
+
+impl<T> VecSingleton<T>
+where
+    T: Clone + Send + Sync + 'static,
+{
+    pub fn new(port: InnerViewPort<dyn SingletonView<Item = Vec<T>>>) -> Arc<RwLock<Self>> {
+        let sgl = Arc::new(RwLock::new(VecSingleton {
+            data: None,
+            cast: port.get_broadcast(),
+        }));
+        port.set_view(Some(sgl.clone()));
+        sgl
+    }
+}
+
+impl<T> Observer<RwLock<Vec<T>>> for VecSingleton<T>
+where
+    T: Clone + Send + Sync + 'static,
+{
+    fn reset(&mut self, view: Option<Arc<RwLock<Vec<T>>>>) {
+        self.data = view;
+        self.cast.notify(&());
+    }
+
+    fn notify(&mut self, _diff: &VecDiff<T>) {
+        self.cast.notify(&());
+    }
+}
+
+impl<T> View for VecSingleton<T>
+where
+    T: Clone + Send + Sync + 'static,
+{
+    type Msg = ();
+}
+
+impl<T> SingletonView for VecSingleton<T>
+where
+    T: Clone + Send + Sync + 'static,
+{
+    type Item = Vec<T>;
+
+    fn get(&self) -> Vec<T> {
+        self.data.as_ref().unwrap().read().unwrap().clone()
+    }
+}
+
+//<<<<>>>><<>><><<>><<<*>>><<>><><<>><<<<>>>>
+
+impl<T> OuterViewPort<RwLock<Vec<T>>>
+where
+    T: Clone + Send + Sync + 'static,
+{
+    pub fn to_singleton(&self) -> OuterViewPort<dyn SingletonView<Item = Vec<T>>> {
+        let port = ViewPort::new();
+        port.add_update_hook(Arc::new(self.0.clone()));
+
+        let vec_sgl = VecSingleton::new(port.inner());
+        self.add_observer(vec_sgl.clone());
+        port.into_outer()
+    }
+}