feat(desktop): integrate native Windows titlebar

desktopApp/src/main/kotlin/com/vnidrop/app/WindowsWindowChrome.kt

@@ -0,0 +1,241 @@
+package com.vnidrop.app
+
+import androidx.compose.foundation.Image
+import androidx.compose.foundation.background
+import androidx.compose.foundation.clickable
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.Row
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.height
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.layout.size
+import androidx.compose.foundation.text.BasicText
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.DisposableEffect
+import androidx.compose.runtime.remember
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.graphics.ColorFilter
+import androidx.compose.ui.graphics.PathFillType
+import androidx.compose.ui.graphics.SolidColor
+import androidx.compose.ui.graphics.StrokeCap
+import androidx.compose.ui.graphics.StrokeJoin
+import androidx.compose.ui.graphics.vector.ImageVector
+import androidx.compose.ui.graphics.vector.PathBuilder
+import androidx.compose.ui.graphics.vector.path
+import androidx.compose.ui.graphics.vector.rememberVectorPainter
+import androidx.compose.ui.layout.boundsInWindow
+import androidx.compose.ui.layout.onGloballyPositioned
+import androidx.compose.ui.platform.LocalDensity
+import androidx.compose.ui.semantics.Role
+import androidx.compose.ui.text.TextStyle
+import androidx.compose.ui.text.font.FontWeight
+import androidx.compose.ui.unit.Dp
+import androidx.compose.ui.unit.dp
+import androidx.compose.ui.unit.sp
+import androidx.compose.ui.window.WindowPlacement
+import androidx.compose.ui.window.WindowScope
+import androidx.compose.ui.window.WindowState
+import com.vnidrop.app.ui.theme.LocalVniDropColors
+
+internal class WindowsChromeConfiguration(
+	val topInset: Dp = 0.dp,
+	val contentTopStartRadius: Dp = 0.dp,
+	val useNativeBackdrop: Boolean = false,
+	val onDarkThemeChanged: (Boolean) -> Unit = {},
+	val chrome: (@Composable () -> Unit)? = null,
+)
+
+@Composable
+internal fun WindowScope.WindowsWindowFrame(
+	windowState: WindowState,
+	content: @Composable (WindowsChromeConfiguration) -> Unit,
+) {
+	val controller = remember(window) { WindowsNativeWindowController.install(window) }
+	DisposableEffect(controller) {
+		onDispose { controller?.close() }
+	}
+	if (controller == null) {
+		content(WindowsChromeConfiguration())
+		return
+	}
+	if (!controller.usesCustomChrome) {
+		content(WindowsChromeConfiguration())
+		return
+	}
+
+	val density = LocalDensity.current
+	val insets = controller.frameInsets
+	Box(
+		modifier = Modifier
+			.fillMaxSize()
+			.padding(
+				start = with(density) { insets.left.toDp() },
+				top = with(density) { insets.top.toDp() },
+				end = with(density) { insets.right.toDp() },
+				bottom = with(density) { insets.bottom.toDp() },
+			),
+	) {
+		content(
+			WindowsChromeConfiguration(
+				topInset = WindowsTitleBarHeight,
+				contentTopStartRadius = DesktopContentCornerRadius,
+				useNativeBackdrop = controller.usesNativeBackdrop,
+				onDarkThemeChanged = controller::setDarkTheme,
+				chrome = {
+					WindowsTitleBar(
+						controller = controller,
+						isMaximized = windowState.placement == WindowPlacement.Maximized,
+					)
+				},
+			),
+		)
+	}
+}
+
+@Composable
+private fun WindowsTitleBar(
+	controller: WindowsNativeWindowController,
+	isMaximized: Boolean,
+) {
+	val colors = LocalVniDropColors.current
+	val foreground = colors.foregroundDefault.copy(alpha = if (controller.isWindowActive) 1f else 0.55f)
+	Box(
+		modifier = Modifier
+			.fillMaxWidth()
+			.height(WindowsTitleBarHeight)
+			.background(if (controller.usesNativeBackdrop) Color.Transparent else colors.backgroundSurface200)
+			.onGloballyPositioned { controller.updateCaptionBounds(it.boundsInWindow()) },
+	) {
+		BasicText(
+			text = "VniDrop",
+			modifier = Modifier.align(Alignment.Center),
+			style = TextStyle(
+				color = foreground,
+				fontSize = 13.sp,
+				fontWeight = FontWeight.SemiBold,
+			),
+		)
+		if (!controller.usesSystemCaptionButtons) {
+			Row(modifier = Modifier.align(Alignment.TopEnd)) {
+				WindowsCaptionButton(
+					button = WindowsCaptionButton.Minimize,
+					icon = WindowsMinimizeIcon,
+					contentDescription = "Minimize window",
+					controller = controller,
+					onClick = controller::minimize,
+				)
+				WindowsCaptionButton(
+					button = WindowsCaptionButton.Maximize,
+					icon = if (isMaximized) WindowsRestoreIcon else WindowsMaximizeIcon,
+					contentDescription = if (isMaximized) "Restore window" else "Maximize window",
+					controller = controller,
+					onClick = controller::toggleMaximize,
+				)
+				WindowsCaptionButton(
+					button = WindowsCaptionButton.Close,
+					icon = WindowsCloseIcon,
+					contentDescription = "Close window",
+					controller = controller,
+					onClick = { controller.postCloseRequest() },
+				)
+			}
+		}
+	}
+}
+
+@Composable
+private fun WindowsCaptionButton(
+	button: WindowsCaptionButton,
+	icon: ImageVector,
+	contentDescription: String,
+	controller: WindowsNativeWindowController,
+	onClick: () -> Unit,
+) {
+	val colors = LocalVniDropColors.current
+	val hovered = controller.hoveredCaptionButton == button
+	val pressed = controller.pressedCaptionButton == button
+	val destructive = button == WindowsCaptionButton.Close && (hovered || pressed)
+	val background = when {
+		destructive -> colors.destructiveDefault
+		pressed -> colors.backgroundOverlayHover
+		hovered -> colors.backgroundOverlayHover
+		else -> Color.Transparent
+	}
+	val foreground = when {
+		destructive -> Color.White
+		controller.isWindowActive -> colors.foregroundDefault
+		else -> colors.foregroundDefault.copy(alpha = 0.55f)
+	}
+	Box(
+		modifier = Modifier
+			.size(width = WindowsCaptionButtonWidth, height = WindowsCaptionButtonHeight)
+			.background(background)
+			.clickable(role = Role.Button, onClick = onClick)
+			.onGloballyPositioned { coordinates ->
+				when (button) {
+					WindowsCaptionButton.Minimize -> controller.updateMinimizeButtonBounds(coordinates.boundsInWindow())
+					WindowsCaptionButton.Maximize -> controller.updateMaximizeButtonBounds(coordinates.boundsInWindow())
+					WindowsCaptionButton.Close -> controller.updateCloseButtonBounds(coordinates.boundsInWindow())
+				}
+			},
+		contentAlignment = Alignment.Center,
+	) {
+		Image(
+			painter = rememberVectorPainter(icon),
+			contentDescription = contentDescription,
+			colorFilter = ColorFilter.tint(foreground),
+			modifier = Modifier.size(24.dp),
+		)
+	}
+}
+
+internal val WindowsTitleBarHeight = WindowsTitleBarHeightDip.dp
+private val WindowsCaptionButtonWidth = 48.dp
+private val WindowsCaptionButtonHeight = 48.dp
+
+private val WindowsMinimizeIcon = windowsCaptionIcon("Minimize") {
+	moveTo(5f, 12f)
+	lineTo(19f, 12f)
+}
+
+private val WindowsMaximizeIcon = windowsCaptionIcon("Maximize") {
+	moveTo(6.5f, 6.5f)
+	lineTo(17.5f, 6.5f)
+	lineTo(17.5f, 17.5f)
+	lineTo(6.5f, 17.5f)
+	close()
+}
+
+private val WindowsRestoreIcon = windowsCaptionIcon("Restore") {
+	moveTo(8.5f, 8.5f)
+	lineTo(18f, 8.5f)
+	lineTo(18f, 18f)
+	lineTo(8.5f, 18f)
+	close()
+	moveTo(6f, 15.5f)
+	lineTo(6f, 6f)
+	lineTo(15.5f, 6f)
+}
+
+private val WindowsCloseIcon = windowsCaptionIcon("Close") {
+	moveTo(6.5f, 6.5f)
+	lineTo(17.5f, 17.5f)
+	moveTo(17.5f, 6.5f)
+	lineTo(6.5f, 17.5f)
+}
+
+private fun windowsCaptionIcon(name: String, block: PathBuilder.() -> Unit): ImageVector =
+	ImageVector.Builder(name, 24.dp, 24.dp, 24f, 24f).apply {
+		path(
+			fill = SolidColor(Color.Transparent),
+			stroke = SolidColor(Color.Black),
+			strokeLineWidth = 1.4f,
+			strokeLineCap = StrokeCap.Square,
+			strokeLineJoin = StrokeJoin.Miter,
+			pathFillType = PathFillType.NonZero,
+			pathBuilder = block,
+		)
+	}.build()

desktopApp/src/main/kotlin/com/vnidrop/app/main.kt

@@ -61,6 +61,7 @@ fun main(args: Array<String>) {
 	FileKit.init(appId = "vnidrop")
 	val externalInvitations = ExternalInvitationController()
 	val linux = DesktopAppearanceBridge.isLinux()
+	val windows = DesktopAppearanceBridge.isWindows()
 	configureInvitationOpenHandler(externalInvitations)
 	args.asSequence()
 		.map(::File)
@@ -75,25 +76,39 @@ fun main(args: Array<String>) {
 			// Compose keeps edge resizers active for this client-decorated Linux window.
 			undecorated = linux,
 		) {
-			App(
+			val dependencies = rememberJvmAppDependencies(externalInvitations)
-				dependencies = rememberJvmAppDependencies(externalInvitations),
+			if (windows) {
-				windowChromeTopInset = if (linux) LinuxTitleBarHeight else 0.dp,
+				WindowsWindowFrame(windowState) { chrome ->
-				windowContentTopStartRadius = if (linux) DesktopContentCornerRadius else 0.dp,
+					App(
-				windowChrome = if (linux) {
+						dependencies = dependencies,
-					{
+						windowChromeTopInset = chrome.topInset,
-						LinuxTitleBar(
+						windowContentTopStartRadius = chrome.contentTopStartRadius,
-							isMaximized = windowState.placement == WindowPlacement.Maximized,
+						useNativeWindowBackdrop = chrome.useNativeBackdrop,
-							onMinimize = { windowState.isMinimized = true },
+						onResolvedDarkThemeChanged = chrome.onDarkThemeChanged,
-							onToggleMaximize = {
+						windowChrome = chrome.chrome,
-								windowState.placement = toggledWindowPlacement(windowState.placement)
+					)
-							},
+				}
-							onClose = ::exitApplication,
+			} else {
-						)
+				App(
-					}
+					dependencies = dependencies,
-				} else {
+					windowChromeTopInset = if (linux) LinuxTitleBarHeight else 0.dp,
-					null
+					windowContentTopStartRadius = if (linux) DesktopContentCornerRadius else 0.dp,
-				},
+					windowChrome = if (linux) {
-			)
+						{
+							LinuxTitleBar(
+								isMaximized = windowState.placement == WindowPlacement.Maximized,
+								onMinimize = { windowState.isMinimized = true },
+								onToggleMaximize = {
+									windowState.placement = toggledWindowPlacement(windowState.placement)
+								},
+								onClose = ::exitApplication,
+							)
+						}
+					} else {
+						null
+					},
+				)
+			}
 		}
 	}
 }
@@ -120,7 +135,7 @@ private val LinuxTitleBarHeight = 48.dp
 private val LinuxWindowControlHitTargetSize = 34.dp
 private val LinuxWindowControlVisualSize = 28.dp
 private val LinuxWindowControlsWidth = 120.dp
-private val DesktopContentCornerRadius = 20.dp
+internal val DesktopContentCornerRadius = 20.dp
 
 @Composable
 @OptIn(ExperimentalComposeUiApi::class)

shared/src/jvmMain/kotlin/com/vnidrop/app/platform/PlatformSystemAppearance.jvm.kt

@@ -8,10 +8,14 @@ actual fun PlatformSystemAppearance(isDarkTheme: Boolean) = Unit
 
 object DesktopAppearanceBridge {
 	fun isLinux(): Boolean = isLinux(System.getProperty("os.name"))
+	fun isWindows(): Boolean = isWindows(System.getProperty("os.name"))
 
 	internal fun isLinux(osName: String): Boolean =
 		osName.startsWith("Linux", ignoreCase = true)
 
+	internal fun isWindows(osName: String): Boolean =
+		osName.startsWith("Windows", ignoreCase = true)
+
 	internal fun toggledWindowState(currentState: Int): Int =
 		if (currentState and Frame.MAXIMIZED_BOTH == Frame.MAXIMIZED_BOTH) {
 			Frame.NORMAL

shared/src/jvmTest/kotlin/com/vnidrop/app/platform/DesktopAppearanceBridgeTest.kt

@@ -14,6 +14,14 @@ class DesktopAppearanceBridgeTest {
 		assertFalse(DesktopAppearanceBridge.isLinux("Windows 11"))
 	}
 
+	@Test
+	fun nativeWindowsChromeIsLimitedToWindows() {
+		assertFalse(DesktopAppearanceBridge.isWindows("Mac OS X"))
+		assertFalse(DesktopAppearanceBridge.isWindows("Linux"))
+		assertTrue(DesktopAppearanceBridge.isWindows("Windows 10"))
+		assertTrue(DesktopAppearanceBridge.isWindows("Windows 11"))
+	}
+
 	@Test
 	fun titlebarDoubleClickTogglesMaximizedWindowState() {
 		assertEquals(Frame.MAXIMIZED_BOTH, DesktopAppearanceBridge.toggledWindowState(Frame.NORMAL))