window focus and scrolling working gooood

src/cg/10-os.cg

@@ -37,6 +37,26 @@ closeWindowById = id \
   i = index id (map (w \ w.id) osState.windows);
   closeWindowByIndex (unwrapOr 0 i);
 
+scrollToWindow = index \
+  windows = osState.windows;
+  widths = map (w \ w.width) windows;
+  gap = 1;
+  windowX = (sum (take index widths)) + (index * gap);
+  windowW = unwrapOr 400 (nth index widths);
+  scrollOffset = osState.wm.scrollOffset;
+  vw = viewport.width;
+  (windowX < scrollOffset
+  | True \ windowX
+  | False \ (windowX + windowW > scrollOffset + vw
+    | True \ windowX + windowW - vw
+    | False \ scrollOffset));
+
+focusWindow = index \
+  batch [
+    osState.wm.focusedIndex := index,
+    osState.wm.scrollOffset := scrollToWindow index
+  ];
+
 onSelect = input \
   result = eval input;
   result
@@ -100,8 +120,8 @@ windowComponent = config \ ui.stateful {
   focusable = True,
   init = {},
   update = state event \ event
-    | Focused \ { state = state, emit = [osState.wm.focusedIndex := config.index] }
-    | ChildFocused \ { state = state, emit = [osState.wm.focusedIndex := config.index] }
+    | Focused \ { state = state, emit = [focusWindow config.index] }
+    | ChildFocused \ { state = state, emit = [focusWindow config.index] }
     | _ \ { state = state, emit = [] },
   view = state \ renderWindow config.window config.isActive
 };
@@ -120,20 +140,6 @@ renderWindows = _ \
     }
   };
 
-scrollToWindow = index \
-  windows = osState.windows;
-  widths = map (w \ w.width) windows;
-  gap = 1;
-  windowX = (sum (take index widths)) + (index * gap);
-  windowW = unwrapOr 400 (nth index widths);
-  scrollOffset = osState.wm.scrollOffset;
-  vw = viewport.width;
-  (windowX < scrollOffset
-  | True \ windowX
-  | False \ (windowX + windowW > scrollOffset + vw
-    | True \ windowX + windowW - vw
-    | False \ scrollOffset));
-
 os = ui.stateful {
   key = "os",
   autoFocus = True,
@@ -146,18 +152,12 @@ os = ui.stateful {
     | Key { key = "ArrowLeft", meta = True } \
       (
       newIndex = max 0 (osState.wm.focusedIndex - 1);
-      { state = state, emit = [
-        osState.wm.focusedIndex := newIndex,
-        osState.wm.scrollOffset := scrollToWindow newIndex
-      ] }
+      { state = state, emit = [focusWindow newIndex] }
       )
     | Key { key = "ArrowRight", meta = True } \
       (
       newIndex = min (len osState.windows - 1) (osState.wm.focusedIndex + 1);
-      { state = state, emit = [
-        osState.wm.focusedIndex := newIndex,
-        osState.wm.scrollOffset := scrollToWindow newIndex
-      ] }
+      { state = state, emit = [focusWindow newIndex] }
       )
     | Key { key = "d", meta = True } \
       { state = state, emit = [closeFocusedWindow 0] }