From 2896799faef838d005158109b12a088126619bd0 Mon Sep 17 00:00:00 2001
From: Michael Sippel <micha@fragmental.art>
Date: Sat, 12 Jun 2021 03:05:05 +0200
Subject: [PATCH] grid offset: use map_key()

---
 nested/src/grid/mod.rs    |  1 -
 nested/src/grid/offset.rs | 75 ++++-----------------------------------
 2 files changed, 7 insertions(+), 69 deletions(-)

diff --git a/nested/src/grid/mod.rs b/nested/src/grid/mod.rs
index 38f9309..e2692a4 100644
--- a/nested/src/grid/mod.rs
+++ b/nested/src/grid/mod.rs
@@ -9,7 +9,6 @@ use {
 };
 
 pub mod offset;
-pub use offset::GridOffset;
 
 //<<<<>>>><<>><><<>><<<*>>><<>><><<>><<<<>>>>
 
diff --git a/nested/src/grid/offset.rs b/nested/src/grid/offset.rs
index 77d9ab1..170a9db 100644
--- a/nested/src/grid/offset.rs
+++ b/nested/src/grid/offset.rs
@@ -4,81 +4,20 @@ use {
     std::sync::RwLock,
     crate::{
         core::{
-            View,
-            Observer,
-            ObserverExt,
-            ObserverBroadcast,
-            InnerViewPort
+            OuterViewPort
         },
-        index::{IndexView},
         grid::{GridView}
     }
 };
 
-pub struct GridOffset<V: GridView + ?Sized> {
-    src: Option<Arc<V>>,
-    offset: Vector2<i16>,
-    cast: Arc<RwLock<ObserverBroadcast<dyn GridView<Item = V::Item>>>>
-}
 
-impl<V: 'static + GridView + ?Sized> GridOffset<V> {
-    pub fn new(port: InnerViewPort<dyn GridView<Item = V::Item>>) -> Arc<RwLock<Self>> {
-        let offset_view =
-            Arc::new(RwLock::new(
-                GridOffset::<V> {
-                    src: None,
-                    offset: Vector2::new(0, 0),
-                    cast: port.get_broadcast()
-                }
-            ));
-
-        port.set_view(Some(offset_view.clone()));
-        offset_view
-    }
-
-    pub fn set_offset(&mut self, new_offset: Vector2<i16>) {
-        let old_area = self.area();
-        self.offset = new_offset;
-        let new_area = self.area();
-
-        if let Some(area) = old_area { self.cast.notify_each(area); }
-        if let Some(area) = new_area { self.cast.notify_each(area); }
-    }
-}
-
-impl<V: GridView + ?Sized> View for GridOffset<V> {
-    type Msg = Point2<i16>;
-}
-
-impl<V: GridView + ?Sized> IndexView<Point2<i16>> for GridOffset<V> {
-    type Item = V::Item;
-
-    fn get(&self, pos: &Point2<i16>) -> Option<Self::Item> {
-        self.src.as_ref()?.get(&(pos - self.offset))
-    }
-
-    fn area(&self) -> Option<Vec<Point2<i16>>> {
-        Some(
-            self.src.as_ref()?
-                .area()?.into_iter()
-                .map(|pos| pos + self.offset)
-                .collect()
+impl<Item> OuterViewPort<dyn GridView<Item = Item>>
+where Item: 'static {
+    pub fn offset(&self, offset: Vector2<i16>) -> OuterViewPort<dyn GridView<Item = Item>> {
+        self.map_key(
+            move |pt| pt + offset,
+            move |pt| Some(pt - offset)
         )
     }
 }
 
-impl<V: GridView + ?Sized> Observer<V> for GridOffset<V> {
-    fn reset(&mut self, view: Option<Arc<V>>) {
-        let old_area = self.area();
-        self.src = view;
-        let new_area = self.area();
-
-        if let Some(area) = old_area { self.cast.notify_each(area); }
-        if let Some(area) = new_area { self.cast.notify_each(area); }
-    }
-
-    fn notify(&mut self, msg: &Point2<i16>) {
-        self.cast.notify(&(msg + self.offset));
-    }
-}
-