From 85209031ef3a201f892eeb0c2e5da0211f33be9c Mon Sep 17 00:00:00 2001
From: Trevor Slocum <trevor@rocketnine.space>
Date: Mon, 13 Sep 2021 19:49:10 -0700
Subject: [PATCH] Highlight pressed keys

---
 key.go      |  2 ++
 keyboard.go | 83 ++++++++++++++++++++++++++++++++++++++++++++---------
 keys.go     |  8 ++++++
 3 files changed, 79 insertions(+), 14 deletions(-)

diff --git a/key.go b/key.go
index f513e7d..9b6cf65 100644
--- a/key.go
+++ b/key.go
@@ -12,6 +12,8 @@ type Key struct {
 
 	x, y int
 	w, h int
+
+	pressed bool
 }
 
 type Input struct {
diff --git a/keyboard.go b/keyboard.go
index 1e30802..74a0f21 100644
--- a/keyboard.go
+++ b/keyboard.go
@@ -4,6 +4,7 @@ import (
 	"image"
 	"image/color"
 	"log"
+	"time"
 
 	"github.com/hajimehoshi/ebiten/v2"
 	"github.com/hajimehoshi/ebiten/v2/examples/resources/fonts"
@@ -28,7 +29,8 @@ type Keyboard struct {
 
 	keys [][]*Key
 
-	background *ebiten.Image
+	background      *ebiten.Image
+	backgroundDirty bool
 
 	op *ebiten.DrawImageOptions
 
@@ -87,7 +89,7 @@ func (k *Keyboard) SetRect(x, y, w, h int) {
 	k.x, k.y, k.w, k.h = x, y, w, h
 
 	k.updateKeyRects()
-	k.drawBackground()
+	k.backgroundDirty = true
 }
 
 func (k *Keyboard) GetKeys() [][]*Key {
@@ -98,13 +100,13 @@ func (k *Keyboard) SetKeys(keys [][]*Key) {
 	k.keys = keys
 
 	k.updateKeyRects()
-	k.drawBackground()
+	k.backgroundDirty = true
 }
 
 func (k *Keyboard) SetLabelFont(face font.Face) {
 	k.labelFont = face
 
-	k.drawBackground()
+	k.backgroundDirty = true
 }
 
 func (k *Keyboard) SetHideShortcuts(shortcuts []ebiten.Key) {
@@ -132,6 +134,10 @@ func (k *Keyboard) updateKeyRects() {
 			key.y = (cellH + cellPaddingH) * row
 			key.w = cellW
 			key.h = cellH
+
+			if i == len(rowKeys)-1 {
+				key.w = k.w - key.x
+			}
 		}
 	}
 }
@@ -175,7 +181,7 @@ func (k *Keyboard) Hit(key *Key) {
 
 	if input.Key == ebiten.KeyShift {
 		k.shift = !k.shift
-		k.drawBackground()
+		k.backgroundDirty = true
 		return
 	} else if k.handleHideKey(input.Key) {
 		// Hidden
@@ -199,25 +205,51 @@ func (k *Keyboard) Update() error {
 			for _, r := range k.internalBuffer {
 				k.inputBuffer <- &Input{Rune: r} // Pass through
 			}
-		}
-		// Read keys
-		for _, key := range allKeys {
-			if inpututil.IsKeyJustPressed(key) {
-				if k.handleHideKey(key) {
-					// Hidden
-					return nil
+		} else {
+			// Read keys
+			for _, key := range allKeys {
+				if inpututil.IsKeyJustPressed(key) {
+					if k.handleHideKey(key) {
+						// Hidden
+						return nil
+					}
+					k.inputBuffer <- &Input{Key: key} // Pass through
 				}
-				k.inputBuffer <- &Input{Key: key} // Pass through
 			}
 		}
 	}
 	// Handle mouse input
-	if inpututil.IsMouseButtonJustPressed(ebiten.MouseButtonLeft) {
+	if inpututil.IsMouseButtonJustReleased(ebiten.MouseButtonLeft) {
 		x, y := ebiten.CursorPosition()
 
 		key := k.at(x, y)
 		if key != nil {
+			for _, rowKeys := range k.keys {
+				for _, rowKey := range rowKeys {
+					rowKey.pressed = false
+				}
+			}
+			key.pressed = true
+			k.backgroundDirty = true
+
 			k.Hit(key)
+
+			// TODO replace with pressUntil
+			go func() {
+				time.Sleep(50 * time.Millisecond)
+
+				key.pressed = false
+				k.backgroundDirty = true
+				ebiten.ScheduleFrame()
+			}()
+		}
+	} else if ebiten.IsMouseButtonPressed(ebiten.MouseButtonLeft) {
+		x, y := ebiten.CursorPosition()
+
+		key := k.at(x, y)
+		if key != nil {
+			key.pressed = true
+			k.backgroundDirty = true
 		}
 	}
 	// Handle touch input
@@ -227,7 +259,19 @@ func (k *Keyboard) Update() error {
 
 		key := k.at(x, y)
 		if key != nil {
+			key.pressed = true
+			k.backgroundDirty = true
+
 			k.Hit(key)
+
+			// TODO replace with pressUntil
+			go func() {
+				time.Sleep(50 * time.Millisecond)
+
+				key.pressed = false
+				k.backgroundDirty = true
+				ebiten.ScheduleFrame()
+			}()
 		}
 	}
 	return nil
@@ -266,10 +310,16 @@ func (k *Keyboard) drawBackground() {
 			y := key.h / 2
 			text.Draw(img, label, k.labelFont, x, y, color.White)
 
+			if key.pressed {
+				k.op.ColorM.Scale(1, 1, 1, 0.6)
+			}
+
 			// Draw key
 			k.op.GeoM.Reset()
 			k.op.GeoM.Translate(float64(key.x), float64(key.y))
 			buffer.DrawImage(img, k.op)
+
+			k.op.ColorM.Reset()
 		}
 	}
 
@@ -282,6 +332,11 @@ func (k *Keyboard) Draw(target *ebiten.Image) {
 		return
 	}
 
+	if k.backgroundDirty {
+		k.drawBackground()
+		k.backgroundDirty = false
+	}
+
 	k.op.GeoM.Reset()
 	k.op.GeoM.Translate(float64(k.x), float64(k.y))
 	k.op.ColorM.Scale(1, 1, 1, k.alpha)
diff --git a/keys.go b/keys.go
index 18ba99b..e24ab19 100644
--- a/keys.go
+++ b/keys.go
@@ -311,6 +311,14 @@ var KeysQWERTY = [][]*Key{
 			UpperInput: &Input{Rune: '?'},
 		},
 	},
+	{
+		{
+			LowerLabel: "Space",
+			UpperLabel: "SPACE",
+			LowerInput: &Input{Rune: ' '},
+			UpperInput: &Input{Rune: ' '},
+		},
+	},
 }
 
 var allKeys = []ebiten.Key{