From 49f1cd79b7eb17604c03186aec0b4a071dcf0829 Mon Sep 17 00:00:00 2001
From: Dima Marhitych <uzhdimka@gmail.com>
Date: Sun, 8 Oct 2023 12:11:40 +0200
Subject: [PATCH] v0.0.7: Added keyboard system

---
 src/backend/document/document.go |  4 ++++
 src/webzen/init.go               |  9 ++++++++
 src/webzen/keys/keys.go          | 39 ++++++++++++++++++++++++++++++++
 tests/test1/test1.go             | 17 ++++++++++----
 4 files changed, 65 insertions(+), 4 deletions(-)
 create mode 100644 src/webzen/keys/keys.go

diff --git a/src/backend/document/document.go b/src/backend/document/document.go
index 981829f..c541147 100644
--- a/src/backend/document/document.go
+++ b/src/backend/document/document.go
@@ -34,6 +34,10 @@ func CreateCanvasElement() canvas {
 	return canvas{cd}
 }
 
+func AddEventListener(event string, f js.Func) {
+	js.Global().Get("document").Call("addEventListener", event, f)
+}
+
 func (e *element) Set(key string, value interface{}) {
 	e.el.Set(key, value)
 }
diff --git a/src/webzen/init.go b/src/webzen/init.go
index 40adff0..05a5c94 100644
--- a/src/webzen/init.go
+++ b/src/webzen/init.go
@@ -5,9 +5,11 @@ package webzen
 
 import (
 	"syscall/js"
+  "time"
 
 	"github.com/dimkauzh/webzen/src/backend/document"
 	"github.com/dimkauzh/webzen/src/backend/window"
+  "github.com/dimkauzh/webzen/src/webzen/keys"
 )
 
 func Init() {
@@ -29,4 +31,11 @@ func Init() {
 		canvas.Set("height", document.DocumentElement.ClientHeight())
 		return nil
 	}))
+
+  keys.SetupEventListeners()
+}
+
+func Update() {
+  time.Sleep(time.Millisecond * 16)
+ 
 }
diff --git a/src/webzen/keys/keys.go b/src/webzen/keys/keys.go
new file mode 100644
index 0000000..06aef74
--- /dev/null
+++ b/src/webzen/keys/keys.go
@@ -0,0 +1,39 @@
+//go:build js && wasm
+// +build js,wasm
+
+package keys
+
+import (
+	"syscall/js"
+
+	"github.com/dimkauzh/webzen/src/backend/document"
+)
+
+var keyPressed = make(map[string]bool)
+
+func SetupEventListeners() {
+	// Initialize event listeners once
+	document.AddEventListener("keydown", js.FuncOf(func(this js.Value, p []js.Value) interface{} {
+		event := p[0]
+		key := event.Get("key").String()
+
+		// Set the key's state to pressed.
+		keyPressed[key] = true
+
+		return nil
+	}))
+
+	document.AddEventListener("keyup", js.FuncOf(func(this js.Value, p []js.Value) interface{} {
+		event := p[0]
+		key := event.Get("key").String()
+
+		// Set the key's state to released.
+		keyPressed[key] = false
+
+		return nil
+	}))
+}
+
+func KeyPressed(key string) bool {
+	return keyPressed[key]
+}
diff --git a/tests/test1/test1.go b/tests/test1/test1.go
index ba4a8a3..0f78869 100644
--- a/tests/test1/test1.go
+++ b/tests/test1/test1.go
@@ -1,14 +1,23 @@
 package main
 
 import (
+
 	"github.com/dimkauzh/webzen/src/webzen"
 	"github.com/dimkauzh/webzen/src/webzen/draw"
+	"github.com/dimkauzh/webzen/src/webzen/keys"
+	"github.com/dimkauzh/webzen/src/webzen/tools"
 )
 
 func main() {
 	webzen.Init()
-	draw.FillBackground([4]int{255, 255, 188, 255})
-	draw.DrawText("Hello under the world!", 21, 100, 100)
-	draw.DrawRect(50, 500, 400, 400, [4]int{146, 255, 123, 255})
-	draw.DrawRect(200, 200, 100, 400, [4]int{146, 255, 123, 255})
+	for {
+		draw.FillBackground([4]int{255, 255, 188, 255})
+		draw.DrawText("Hello under the world!", 21, 100, 100)
+		draw.DrawRect(50, 500, 400, 400, [4]int{146, 255, 123, 255})
+		draw.DrawRect(200, 200, 100, 400, [4]int{146, 255, 123, 255})
+		if keys.KeyPressed("a") {
+			tools.Print("A key pressed")
+		}
+    webzen.Update()
+	}
 }