exp/textinput: bug fix: go-vet error

Updates #1162

exp/textinput/textinput_darwin.go

@@ -16,36 +16,13 @@
 
 package textinput
 
-// TODO: Remove Cgo after ebitengine/purego#143 is resolved.
-
 // #cgo CFLAGS: -x objective-c
 // #cgo LDFLAGS: -framework Cocoa
-//
-// #import <Cocoa/Cocoa.h>
-//
-// @interface TextInputClient : NSView<NSTextInputClient>
-// @end
-//
-// static TextInputClient* getTextInputClient() {
-//   static TextInputClient* textInputClient;
-//   if (!textInputClient) {
-//     textInputClient = [[TextInputClient alloc] init];
-//   }
-//   return textInputClient;
-// }
-//
-// static void start(int x, int y) {
-//   TextInputClient* textInputClient = getTextInputClient();
-//   NSWindow* window = [[NSApplication sharedApplication] mainWindow];
-//   [[window contentView] addSubview: textInputClient];
-//   [window makeFirstResponder: textInputClient];
-//
-//   y = [[window contentView] frame].size.height - y - 4;
-//   [textInputClient setFrame:NSMakeRect(x, y, 1, 1)];
-// }
 import "C"
 
 import (
+	"github.com/ebitengine/purego/objc"
+
 	"github.com/hajimehoshi/ebiten/v2/internal/ui"
 )
 
@@ -60,7 +37,7 @@ func (t *textInput) Start(x, y int) (chan State, func()) {
 	var session *session
 	ui.Get().RunOnMainThread(func() {
 		t.end()
-		C.start(C.int(x), C.int(y))
+		start(x, y)
 		session = newSession()
 		t.session = session
 	})
@@ -99,3 +76,57 @@ func (t *textInput) end() {
 		t.session = nil
 	}
 }
+
+var (
+	selAddSubview         = objc.RegisterName("addSubview:")
+	selAlloc              = objc.RegisterName("alloc")
+	selContentView        = objc.RegisterName("contentView")
+	selFrame              = objc.RegisterName("frame")
+	selInit               = objc.RegisterName("init")
+	selMainWindow         = objc.RegisterName("mainWindow")
+	selMakeFirstResponder = objc.RegisterName("makeFirstResponder:")
+	selSetFrame           = objc.RegisterName("setFrame:")
+	selSharedApplication  = objc.RegisterName("sharedApplication")
+
+	idNSApplication = objc.ID(objc.GetClass("NSApplication"))
+)
+
+var theTextInputClient objc.ID
+
+func getTextInputClient() objc.ID {
+	if theTextInputClient == 0 {
+		class := objc.ID(objc.GetClass("TextInputClient"))
+		theTextInputClient = class.Send(selAlloc).Send(selInit)
+	}
+	return theTextInputClient
+}
+
+type nsPoint struct {
+	x float64
+	y float64
+}
+
+type nsSize struct {
+	width  float64
+	height float64
+}
+
+type nsRect struct {
+	origin nsPoint
+	size   nsSize
+}
+
+func start(x, y int) {
+	t := getTextInputClient()
+	window := idNSApplication.Send(selSharedApplication).Send(selMainWindow)
+	contentView := window.Send(selContentView)
+	contentView.Send(selAddSubview, t)
+	window.Send(selMakeFirstResponder, t)
+
+	r := objc.Send[nsRect](contentView, selFrame)
+	y = int(r.size.height) - y - 4
+	t.Send(selSetFrame, nsRect{
+		origin: nsPoint{float64(x), float64(y)},
+		size:   nsSize{1, 1},
+	})
+}

exp/textinput/textinput_darwin.m

@@ -14,6 +14,8 @@
 
 //go:build !ios
 
+// TODO: Remove Cgo with PureGo (#1162).
+
 #import <Cocoa/Cocoa.h>
 
 void ebitengine_textinput_update(const char* text, int start, int end, BOOL committed);

go.mod

@@ -5,8 +5,8 @@ go 1.18
 require (
 	github.com/ebitengine/gomobile v0.0.0-20240329170434-1771503ff0a8
 	github.com/ebitengine/hideconsole v1.0.0
-	github.com/ebitengine/oto/v3 v3.3.0-alpha.0.20240401142028-457cd3ebf3f3
-	github.com/ebitengine/purego v0.8.0-alpha
+	github.com/ebitengine/oto/v3 v3.3.0-alpha.1
+	github.com/ebitengine/purego v0.8.0-alpha.0.20240404024320-d0aedd0f4393
 	github.com/go-text/typesetting v0.1.1-0.20240402181327-ced1d6822703
 	github.com/hajimehoshi/bitmapfont/v3 v3.0.0
 	github.com/hajimehoshi/go-mp3 v0.3.4

go.sum

@@ -2,10 +2,10 @@ github.com/ebitengine/gomobile v0.0.0-20240329170434-1771503ff0a8 h1:5e8X7WEdOWr
 github.com/ebitengine/gomobile v0.0.0-20240329170434-1771503ff0a8/go.mod h1:tWboRRNagZwwwis4QIgEFG1ZNFwBJ3LAhSLAXAAxobQ=
 github.com/ebitengine/hideconsole v1.0.0 h1:5J4U0kXF+pv/DhiXt5/lTz0eO5ogJ1iXb8Yj1yReDqE=
 github.com/ebitengine/hideconsole v1.0.0/go.mod h1:hTTBTvVYWKBuxPr7peweneWdkUwEuHuB3C1R/ielR1A=
-github.com/ebitengine/oto/v3 v3.3.0-alpha.0.20240401142028-457cd3ebf3f3 h1:4vw8U48AKjRSXjwWZLi7g/xA6wNM7PjGNh7TBNES6sI=
-github.com/ebitengine/oto/v3 v3.3.0-alpha.0.20240401142028-457cd3ebf3f3/go.mod h1:T2/VV0UWG97GEEf4kORMU2nCneYT/YmwSTxPutSVaUg=
-github.com/ebitengine/purego v0.8.0-alpha h1:xWsUo8xQZLH8f9TzXXSvs/qjc2s6rhNGYxEo5Qd10so=
-github.com/ebitengine/purego v0.8.0-alpha/go.mod h1:ah1In8AOtksoNK6yk5z1HTJeUkC1Ez4Wk2idgGslMwQ=
+github.com/ebitengine/oto/v3 v3.3.0-alpha.1 h1:J2nBmQwPLKc4+yLObytq1jKNydI96l6EjZfgefiqGbk=
+github.com/ebitengine/oto/v3 v3.3.0-alpha.1/go.mod h1:T2/VV0UWG97GEEf4kORMU2nCneYT/YmwSTxPutSVaUg=
+github.com/ebitengine/purego v0.8.0-alpha.0.20240404024320-d0aedd0f4393 h1:8mFaXjlt/DLC5MlrnsR71EpK196kVYvPTC2soh06rGU=
+github.com/ebitengine/purego v0.8.0-alpha.0.20240404024320-d0aedd0f4393/go.mod h1:y8L+ZRLphbdPW2xs41fur/KaW57yTzrFsqsclHyHrTM=
 github.com/go-text/typesetting v0.1.1-0.20240402181327-ced1d6822703 h1:AqtMl9yw7r319Ah4W2afQm3Ql+PEsQKHds18tGvKhog=
 github.com/go-text/typesetting v0.1.1-0.20240402181327-ced1d6822703/go.mod h1:2+owI/sxa73XA581LAzVuEBZ3WEEV2pXeDswCH/3i1I=
 github.com/go-text/typesetting-utils v0.0.0-20240317173224-1986cbe96c66 h1:GUrm65PQPlhFSKjLPGOZNPNxLCybjzjYBzjfoBGaDUY=