From a6f958ccfbebc047e24d8a653053bca6e6b98670 Mon Sep 17 00:00:00 2001
From: David Ashby <delta.mu.alpha@gmail.com>
Date: Sun, 4 Jul 2021 13:49:53 -0400
Subject: [PATCH] support ratio layouts

---
 ui/ui.go      | 63 +++++++++++++++++++++++++++++++++++++++++++++++----
 ui/ui_test.go | 62 ++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 121 insertions(+), 4 deletions(-)

diff --git a/ui/ui.go b/ui/ui.go
index 40849fe..e1fc202 100644
--- a/ui/ui.go
+++ b/ui/ui.go
@@ -12,10 +12,11 @@ type Drawable interface {
 }
 
 type Offsets struct {
-	Top    int
-	Bottom int
-	Left   int
-	Right  int
+	Top     int
+	Bottom  int
+	Left    int
+	Right   int
+	Percent int
 }
 
 type Contents []struct {
@@ -27,6 +28,8 @@ const (
 	LayoutUnmanaged = iota
 	LayoutHorizontalEven
 	LayoutVerticalEven
+	LayoutHorizontalPercent
+	LayoutVerticalPercent
 )
 
 // A Container has no visible UI of its own, but arranges sub-components on the screen.
@@ -87,6 +90,58 @@ func (c *Container) SetSize(x, y, h, w int) {
 			}
 			c.contents[r].Container.SetSize(x, y, h, w)
 		}
+	} else if c.layoutMethod == LayoutHorizontalPercent {
+		// first, work out overall distribution
+		total := 0
+		for r := range c.contents {
+			// `0` or negatives are set as minimum
+			if c.contents[r].Offsets.Percent < 1 {
+				total += 1
+			} else {
+				total += c.contents[r].Offsets.Percent
+			}
+		}
+		carry := 0
+		// push around containers
+		for r := range c.contents {
+			ratio := (float64(c.contents[r].Offsets.Percent) / float64(total))
+			w := int(float64(c.w) * ratio)
+			h := c.h
+			x := c.x + carry
+			y := c.y
+			carry += w
+			// and add any remaining space to the last container
+			if r == len(c.contents)-1 {
+				w += (c.w - carry)
+			}
+			c.contents[r].Container.SetSize(x, y, h, w)
+		}
+	} else if c.layoutMethod == LayoutVerticalPercent {
+		// first, work out overall distribution
+		total := 0
+		for r := range c.contents {
+			// `0` or negatives are set as minimum
+			if c.contents[r].Offsets.Percent < 1 {
+				total += 1
+			} else {
+				total += c.contents[r].Offsets.Percent
+			}
+		}
+		carry := 0
+		// push around containers
+		for r := range c.contents {
+			ratio := (float64(c.contents[r].Offsets.Percent) / float64(total))
+			w := c.w
+			h := int(float64(c.h) * ratio)
+			x := c.x
+			y := c.y + carry
+			carry += h
+			// and add any remaining space to the last container
+			if r == len(c.contents)-1 {
+				h += (c.h - carry)
+			}
+			c.contents[r].Container.SetSize(x, y, h, w)
+		}
 	} else {
 		for r := range c.contents {
 			x := c.x + c.contents[r].Offsets.Left
diff --git a/ui/ui_test.go b/ui/ui_test.go
index 90982bf..caabc32 100644
--- a/ui/ui_test.go
+++ b/ui/ui_test.go
@@ -55,6 +55,7 @@ func TestContainerTwoBoxesHStack(t *testing.T) {
 		t.Fail()
 	}
 }
+
 func TestContainerThreeBoxesUnevenHStack(t *testing.T) {
 	expect := `┌─ one ──┐┌─ two ──┐┌─ three 
 │        ││        ││       │
@@ -82,6 +83,34 @@ func TestContainerThreeBoxesUnevenHStack(t *testing.T) {
 	}
 }
 
+func TestContainerTwoBoxesHPercentStack(t *testing.T) {
+	expect := `┌─ one ──────┐┌─ two ┐
+│            ││      │
+│            ││      │
+│            ││      │
+└────────────┘└──────┘
+`
+	m := &MockScreen{}
+	one := NewBox("one", nil, Contents{})
+	two := NewBox("two", nil, Contents{})
+	container := NewContainer(
+		Contents{
+			{Container: one, Offsets: Offsets{Percent: 2}},
+			{Container: two, Offsets: Offsets{Percent: 1}}},
+		LayoutHorizontalPercent,
+	)
+	m.Init()
+	m.Resize(0, 0, 5, 22)
+	container.SetSize(0, 0, 5, 22)
+	container.Draw(m)
+	result := m.DumpContents()
+	if result != expect {
+		fmt.Printf("expected:\n%+v", expect)
+		fmt.Printf("actual:\n%+v", result)
+		t.Fail()
+	}
+}
+
 func TestContainerTwoBoxesVStack(t *testing.T) {
 	expect := `┌─ one ──┐
 │        │
@@ -112,3 +141,36 @@ func TestContainerTwoBoxesVStack(t *testing.T) {
 		t.Fail()
 	}
 }
+
+func TestContainerTwoBoxesPercentageVStack(t *testing.T) {
+	expect := `┌─ one ──┐
+│        │
+│        │
+│        │
+│        │
+└────────┘
+┌─ two ──┐
+│        │
+│        │
+└────────┘
+`
+	m := &MockScreen{}
+	one := NewBox("one", nil, Contents{})
+	two := NewBox("two", nil, Contents{})
+	container := NewContainer(
+		Contents{
+			{Container: one, Offsets: Offsets{Percent: 2}},
+			{Container: two, Offsets: Offsets{Percent: 1}}},
+		LayoutVerticalPercent,
+	)
+	m.Init()
+	m.Resize(0, 0, 10, 10)
+	container.SetSize(0, 0, 10, 10)
+	container.Draw(m)
+	result := m.DumpContents()
+	if result != expect {
+		fmt.Printf("expected:\n%+v", expect)
+		fmt.Printf("actual:\n%+v", result)
+		t.Fail()
+	}
+}