1 files changed, 58 insertions, 0 deletions
diff --git a/focus.go b/focus.go
new file mode 100644
index 0000000..331d232
--- /dev/null
+++ b/focus.go
@@ -0,0 +1,58 @@
+package main
+
+type Focus struct {
+	widgets [][]chan bool
+	p       Point // currently focused widget
+}
+
+func NewFocus(rows []int) Focus {
+	f := Focus{
+		make([][]chan bool, len(rows)),
+		Point{},
+	}
+	for i := range f.widgets {
+		f.widgets[i] = make([]chan bool, rows[i])
+		for j := range f.widgets[i] {
+			f.widgets[i][j] = make(chan bool)
+		}
+	}
+	return f
+}
+
+func (f *Focus) Left() {
+	f.widgets[f.p.Y][f.p.X] <- false
+	if f.p.X <= 0 {
+		f.p.X = len(f.widgets[f.p.Y]) - 1
+	} else {
+		f.p.X--
+	}
+	f.widgets[f.p.Y][f.p.X] <- true
+}
+
+func (f *Focus) Right() {
+	f.widgets[f.p.Y][f.p.X] <- false
+	f.p.X = (f.p.X + 1) % len(f.widgets[f.p.Y])
+	f.widgets[f.p.Y][f.p.X] <- true
+}
+
+func (f *Focus) Up() {
+	f.widgets[f.p.Y][f.p.X] <- false
+	if f.p.Y <= 0 {
+		f.p.Y = len(f.widgets) - 1
+	} else {
+		f.p.Y--
+	}
+	f.p.X = min(f.p.X, len(f.widgets[f.p.Y])-1)
+	f.widgets[f.p.Y][f.p.X] <- true
+}
+
+func (f *Focus) Down() {
+	f.widgets[f.p.Y][f.p.X] <- false
+	f.p.Y = (f.p.Y + 1) % len(f.widgets)
+	f.p.X = min(f.p.X, len(f.widgets[f.p.Y])-1)
+	f.widgets[f.p.Y][f.p.X] <- true
+}
+
+type Point struct {
+	X, Y int
+}