From def20b5d59957b6cdf646de9c2f720c483314695 Mon Sep 17 00:00:00 2001
From: sqshq <sqshq@sqshq.com>
Date: Sat, 2 Mar 2019 16:30:16 -0500
Subject: [PATCH] added up/down/right/left selection capabilities

---
 component/geometry.go | 40 +++++++++++++++++++++++++++
 component/layout.go   | 64 ++++++++++++++++++++++++++++++++++---------
 2 files changed, 91 insertions(+), 13 deletions(-)
 create mode 100644 component/geometry.go

diff --git a/component/geometry.go b/component/geometry.go
new file mode 100644
index 0000000..39b8a10
--- /dev/null
+++ b/component/geometry.go
@@ -0,0 +1,40 @@
+package component
+
+import (
+	"image"
+	"math"
+)
+
+func getRectLeftAgeCenter(rect image.Rectangle) image.Point {
+	return image.Point{
+		X: rect.Min.X,
+		Y: rect.Min.Y + rect.Dy()/2,
+	}
+}
+
+func getRectRightAgeCenter(rect image.Rectangle) image.Point {
+	return image.Point{
+		X: rect.Max.X,
+		Y: rect.Min.Y + rect.Dy()/2,
+	}
+}
+
+func getRectTopAgeCenter(rect image.Rectangle) image.Point {
+	return image.Point{
+		X: rect.Min.X + rect.Dx()/2,
+		Y: rect.Min.Y,
+	}
+}
+
+func getRectBottomAgeCenter(rect image.Rectangle) image.Point {
+	return image.Point{
+		X: rect.Min.X + rect.Dx()/2,
+		Y: rect.Max.Y,
+	}
+}
+
+func getDistance(p1 image.Point, p2 image.Point) float64 {
+	x := math.Abs(float64(p1.X - p2.X))
+	y := math.Abs(float64(p1.Y - p2.Y))
+	return math.Sqrt(x*x + y*y)
+}
diff --git a/component/layout.go b/component/layout.go
index 26e1d9c..d22b94c 100644
--- a/component/layout.go
+++ b/component/layout.go
@@ -5,6 +5,7 @@ import (
 	"github.com/sqshq/sampler/config"
 	"github.com/sqshq/sampler/console"
 	ui "github.com/sqshq/termui"
+	"image"
 	"math"
 )
 
@@ -126,9 +127,7 @@ func (l *Layout) HandleConsoleEvent(e string) {
 			chart := l.getSelectedComponent().Drawable.(*runchart.RunChart)
 			chart.MoveSelection(-1)
 		case ModeComponentSelect:
-			if l.selection > 0 {
-				l.selection--
-			}
+			l.moveSelection(e)
 			l.menu.highlight(l.getComponent(l.selection))
 		case ModeComponentMove:
 			l.getSelectedComponent().Move(-1, 0)
@@ -144,9 +143,7 @@ func (l *Layout) HandleConsoleEvent(e string) {
 			chart := l.getSelectedComponent().Drawable.(*runchart.RunChart)
 			chart.MoveSelection(1)
 		case ModeComponentSelect:
-			if l.selection < len(l.Components)-1 {
-				l.selection++
-			}
+			l.moveSelection(e)
 			l.menu.highlight(l.getComponent(l.selection))
 		case ModeComponentMove:
 			l.getSelectedComponent().Move(1, 0)
@@ -159,9 +156,7 @@ func (l *Layout) HandleConsoleEvent(e string) {
 			l.changeMode(ModeComponentSelect)
 			l.menu.highlight(l.getComponent(l.selection))
 		case ModeComponentSelect:
-			if l.selection > 0 {
-				l.selection--
-			}
+			l.moveSelection(e)
 			l.menu.highlight(l.getComponent(l.selection))
 		case ModeMenuOptionSelect:
 			l.menu.up()
@@ -176,9 +171,7 @@ func (l *Layout) HandleConsoleEvent(e string) {
 			l.changeMode(ModeComponentSelect)
 			l.menu.highlight(l.getComponent(l.selection))
 		case ModeComponentSelect:
-			if l.selection < len(l.Components)-1 {
-				l.selection++
-			}
+			l.moveSelection(e)
 			l.menu.highlight(l.getComponent(l.selection))
 		case ModeMenuOptionSelect:
 			l.menu.down()
@@ -194,7 +187,6 @@ func (l *Layout) ChangeDimensions(width, height int) {
 	l.SetRect(0, 0, width, height)
 }
 
-// TODO func to get prev/next component navigating left/right/top/bottom
 func (l *Layout) getComponent(i int) Component {
 	return l.Components[i]
 }
@@ -203,6 +195,52 @@ func (l *Layout) getSelectedComponent() *Component {
 	return &l.Components[l.selection]
 }
 
+func (l *Layout) moveSelection(direction string) {
+
+	previouslySelected := *l.getSelectedComponent()
+	newlySelectedIndex := l.selection
+
+	for i, current := range l.Components {
+
+		if current == previouslySelected {
+			continue
+		}
+
+		if newlySelectedIndex < 0 {
+			newlySelectedIndex = i
+		}
+
+		var previouslySelectedCornerPoint image.Point
+		var newlySelectedCornerPoint image.Point
+		var currentCornerPoint image.Point
+
+		switch direction {
+		case console.KeyLeft:
+			previouslySelectedCornerPoint = getRectLeftAgeCenter(previouslySelected.Drawable.GetRect())
+			newlySelectedCornerPoint = getRectRightAgeCenter(l.getComponent(newlySelectedIndex).Drawable.GetRect())
+			currentCornerPoint = getRectRightAgeCenter(current.Drawable.GetRect())
+		case console.KeyRight:
+			previouslySelectedCornerPoint = getRectRightAgeCenter(previouslySelected.Drawable.GetRect())
+			newlySelectedCornerPoint = getRectLeftAgeCenter(l.getComponent(newlySelectedIndex).Drawable.GetRect())
+			currentCornerPoint = getRectLeftAgeCenter(current.Drawable.GetRect())
+		case console.KeyUp:
+			previouslySelectedCornerPoint = getRectTopAgeCenter(previouslySelected.Drawable.GetRect())
+			newlySelectedCornerPoint = getRectBottomAgeCenter(l.getComponent(newlySelectedIndex).Drawable.GetRect())
+			currentCornerPoint = getRectBottomAgeCenter(current.Drawable.GetRect())
+		case console.KeyDown:
+			previouslySelectedCornerPoint = getRectBottomAgeCenter(previouslySelected.Drawable.GetRect())
+			newlySelectedCornerPoint = getRectTopAgeCenter(l.getComponent(newlySelectedIndex).Drawable.GetRect())
+			currentCornerPoint = getRectTopAgeCenter(current.Drawable.GetRect())
+		}
+
+		if getDistance(previouslySelectedCornerPoint, currentCornerPoint) < getDistance(previouslySelectedCornerPoint, newlySelectedCornerPoint) {
+			newlySelectedIndex = i
+		}
+	}
+
+	l.selection = newlySelectedIndex
+}
+
 func (l *Layout) Draw(buffer *ui.Buffer) {
 
 	columnWidth := float64(l.GetRect().Dx()) / float64(columnsCount)