Snap windows to the desktop grid and to whole lines, font size picker (10 to 18), white text in settings dialogs, bump to 0.1.12

- After a move, windows snap to the Windows desktop icon grid; after a resize,
  the window height is trimmed so the scrollback ends on a whole line.
- The font size slider is replaced by square 10 to 18 buttons. Sizes saved by
  the old slider round to the nearest picker size.
- Settings and font dialogs always use white text, so a dark window text color
  no longer makes their labels invisible.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

build.gradle.kts

@@ -6,7 +6,7 @@ plugins {
 }
 
 group = "com.tpuahsiew.wirc"
-version = "0.1.11"
+version = "0.1.12"
 
 // No project-level repositories{} block here: settings.gradle.kts sets
 // dependencyResolutionManagement.repositoriesMode = FAIL_ON_PROJECT_REPOS and already
@@ -38,7 +38,7 @@ compose.desktop {
             appResourcesRootDir.set(project.file("installerResources"))
             targetFormats(TargetFormat.Msi, TargetFormat.Exe)
             packageName = "wIRC"
-            packageVersion = "0.1.11"
+            packageVersion = "0.1.12"
             windows {
                 menuGroup = "wIRC"
                 upgradeUuid = "8f14e45f-ceea-4a5e-9c3b-5b1f0e8c2b7a"

src/main/kotlin/Main.kt

@@ -51,6 +51,8 @@ fun main() = application {
     // Loaded once here (not per-window) so the alias map is truly global - every
     // ChannelWindow's command router reads from this same AliasRepository singleton.
     AliasRepository.init()
+    // Ask Windows for the desktop icon grid now, so the first window drag can already snap to it
+    ui.DesktopGrid.refreshAsync()
 
     val repo = remember { ServerRepository(appRoot) }
     val prefsRepo = remember { WindowPrefsRepository(appRoot) }
@@ -85,6 +87,9 @@ fun main() = application {
     // ("wirc-main__main"), same as every channel and PM window - see WindowPlacement.kt.
     val mainWindowState = rememberPersistentWindowState(prefsRepo, MAIN_BUFFER_KEY.storageId(), DpSize(800.dp, 700.dp))
     val mainDisplaySettings by prefsRepo.settingsFor(MAIN_BUFFER_KEY.storageId()).collectAsState()
+    // Snap to the desktop grid after a move, and to whole lines after a resize
+    val mainLineGap = ui.rememberLineGap()
+    ui.WindowSnapping(mainWindowState, mainLineGap, osFrame = true)
 
     // There's no persistent tray/notification surface on this build, so closing the main
     // server-list window quits the whole app (and every channel window with it) - the
@@ -98,6 +103,7 @@ fun main() = application {
         icon = painterResource("icon.png"),
         state = mainWindowState
     ) {
+        androidx.compose.runtime.CompositionLocalProvider(ui.LocalLineGap provides mainLineGap) {
         MaterialTheme(colorScheme = neutralDarkScheme) {
             Surface {
                 MainScreen(
@@ -113,6 +119,7 @@ fun main() = application {
                 )
             }
         }
+        }
     }
 
     openBuffers.forEach { bufferKey ->

src/main/kotlin/data/WindowPrefsRepository.kt

@@ -10,6 +10,13 @@ import java.nio.file.Files
 import java.nio.file.StandardCopyOption
 import java.util.concurrent.ConcurrentHashMap
 
+// Font sizes offered in the settings dialog (whole sizes only, same range as QuickClaude)
+const val MIN_FONT_SIZE = 10
+const val MAX_FONT_SIZE = 18
+
+private fun pickerFontSize(size: Float): Float =
+    Math.round(size).coerceIn(MIN_FONT_SIZE, MAX_FONT_SIZE).toFloat()
+
 data class WindowDisplaySettings(
     val backgroundAlpha: Float = 0.85f,   // 0f = fully transparent, 1f = fully opaque
     val textColorMircIndex: Int = 0,   // index into the standard mIRC palette; 0 = white
@@ -63,7 +70,7 @@ class WindowPrefsRepository(rootDir: File) {
 
     fun setTextColorMircIndex(bufferKeyId: String, index: Int) = update(bufferKeyId) { it.copy(textColorMircIndex = index) }
 
-    fun setFontSize(bufferKeyId: String, fontSize: Float) = update(bufferKeyId) { it.copy(fontSize = fontSize) }
+    fun setFontSize(bufferKeyId: String, fontSize: Float) = update(bufferKeyId) { it.copy(fontSize = pickerFontSize(fontSize)) }
 
     fun setFontId(bufferKeyId: String, fontId: String) = update(bufferKeyId) { it.copy(fontId = fontId) }
 
@@ -109,7 +116,8 @@ class WindowPrefsRepository(rootDir: File) {
                 stored[key] = WindowDisplaySettings(
                     backgroundAlpha = o.optDouble("backgroundAlpha", 0.85).toFloat(),
                     textColorMircIndex = o.optInt("textColorMircIndex", 0),
-                    fontSize = o.optDouble("fontSize", 14.0).toFloat(),
+                    // Sizes saved by the old slider (any value from 10 to 24) round to the nearest picker size
+                    fontSize = pickerFontSize(o.optDouble("fontSize", 14.0).toFloat()),
                     fontId = o.optString("fontId", "monospace"),
                     showUserList = o.optBoolean("showUserList", true),
                     mentionHighlightColorArgb = o.optLong("mentionHighlightColorArgb", 0x40FFA500L).toInt(),

src/main/kotlin/ui/ChannelScreen.kt

@@ -83,6 +83,8 @@ import androidx.compose.ui.window.rememberDialogState
 import data.ChannelBuffer
 import data.ChannelUser
 import data.IrcMessage
+import data.MAX_FONT_SIZE
+import data.MIN_FONT_SIZE
 import data.MessageKind
 import data.WindowDisplaySettings
 import irc.extractImageUrls
@@ -102,6 +104,7 @@ import java.net.URL
 import java.text.SimpleDateFormat
 import java.util.*
 import kotlin.math.floor
+import kotlin.math.roundToInt
 
 // Title-bar button fade (nicklist / settings / minimize / close). The buttons sit at
 // TITLE_BAR_BUTTON_REST_ALPHA until hovered, then animate to TITLE_BAR_BUTTON_HOVER_ALPHA
@@ -417,7 +420,9 @@ fun WindowScope.ChannelScreen(
                         Surface {
                             WindowSettingsPanel(
                                 displaySettings = displaySettings,
-                                textColor = textColor,
+                                // Always white: the dialog is black, so the window's own text
+                                // color (black, say) would make every label invisible here
+                                textColor = Color.White,
                                 onAlphaChange = onAlphaChange,
                                 onTextColorChange = onTextColorChange,
                                 onFontSizeChange = onFontSizeChange,
@@ -859,10 +864,14 @@ fun MessageScrollback(
         // real cause was a race between the scroll effect and the LazyColumn's
         // own layout catching up to new items - see the scroll effects below.
         val snappedHeight = if (lineHeightDp > 0.dp) {
-            lineHeightDp * floor(maxHeight / lineHeightDp).toInt()
+            minOf(maxHeight, lineHeightDp * wholeLines(maxHeight, lineHeightDp))
         } else {
             maxHeight
         }
+        // Tells the window how much space is left under the last whole line, so a resize can
+        // trim the window itself to fit (see WindowSnapping.kt)
+        val lineGap = LocalLineGap.current
+        SideEffect { lineGap?.gap = maxHeight - snappedHeight }
 
         // NOTE: this used to also re-snap the scroll *offset* to the first
         // visible item on every resize/font-size change, to fix a partial line
@@ -1441,13 +1450,24 @@ private fun WindowSettingsPanel(
             colors = sliderColors
         )
         Spacer(Modifier.height(4.dp))
-        Text("Font size", color = textColor, style = MaterialTheme.typography.bodySmall)
-        Slider(
-            value = displaySettings.fontSize,
-            onValueChange = onFontSizeChange,
-            valueRange = 10f..24f,
-            colors = sliderColors
-        )
+        Text("Font size:", color = textColor, style = MaterialTheme.typography.bodySmall)
+        // Fixed sizes 10 to 18 (same as QuickClaude's Font size menu), square boxes in a row
+        val currentSize = displaySettings.fontSize.roundToInt()
+        Row(horizontalArrangement = Arrangement.spacedBy(4.dp)) {
+            for (size in MIN_FONT_SIZE..MAX_FONT_SIZE) {
+                val selected = size == currentSize
+                Box(
+                    modifier = Modifier
+                        .size(28.dp)
+                        .background(if (selected) Color.White.copy(alpha = 0.25f) else Color.Transparent)
+                        .border(1.dp, if (selected) Color.White else Color.White.copy(alpha = 0.35f))
+                        .clickableNoRipple { onFontSizeChange(size.toFloat()) },
+                    contentAlignment = Alignment.Center
+                ) {
+                    Text(size.toString(), color = textColor, fontSize = 12.sp)
+                }
+            }
+        }
         Spacer(Modifier.height(4.dp))
         Text("Font:", color = textColor, style = MaterialTheme.typography.bodySmall)
         FontPickerList(displaySettings.fontId, textColor, onFontChange)

src/main/kotlin/ui/ChannelWindow.kt

@@ -3,6 +3,7 @@ package ui
 import androidx.compose.material3.ColorScheme
 import androidx.compose.material3.MaterialTheme
 import androidx.compose.runtime.Composable
+import androidx.compose.runtime.CompositionLocalProvider
 import androidx.compose.runtime.LaunchedEffect
 import androidx.compose.runtime.collectAsState
 import androidx.compose.runtime.derivedStateOf
@@ -74,6 +75,9 @@ fun ChannelWindow(
     // Restored from window_prefs.json (or cascaded if there's no usable saved position)
     // and saved back on move/resize/close - see WindowPlacement.kt.
     val windowState = rememberPersistentWindowState(prefsRepo, bufferKey.storageId(), DpSize(800.dp, 600.dp))
+    // Snap to the desktop grid after a move, and to whole lines after a resize
+    val lineGap = rememberLineGap()
+    WindowSnapping(windowState, lineGap)
 
     // undecorated + transparent trade the native OS title bar for real per-pixel window
     // transparency (Windows only honors transparency on undecorated windows) - ChannelScreen
@@ -89,6 +93,7 @@ fun ChannelWindow(
         transparent = true,
         resizable = true
     ) {
+        CompositionLocalProvider(LocalLineGap provides lineGap) {
         MaterialTheme(colorScheme = colorScheme) {
                 ChannelScreen(
                     windowState = windowState,
@@ -198,5 +203,6 @@ fun ChannelWindow(
                     }
                 )
         }
+        }
     }
 }

src/main/kotlin/ui/MainScreen.kt

@@ -205,9 +205,9 @@ fun MainScreen(
             MaterialTheme(colorScheme = colorScheme) {
                 Surface {
                     Column(modifier = Modifier.fillMaxSize().padding(8.dp).verticalScroll(rememberScrollState())) {
-                        Text("Server messages font:", color = textColor, style = MaterialTheme.typography.bodySmall)
+                        Text("Server messages font:", color = Color.White, style = MaterialTheme.typography.bodySmall)
                         Spacer(Modifier.height(4.dp))
-                        FontPickerList(displaySettings.fontId, textColor, onFontChange)
+                        FontPickerList(displaySettings.fontId, Color.White, onFontChange)
                     }
                 }
             }

src/main/kotlin/ui/WindowSnapping.kt

@@ -0,0 +1,204 @@
+package ui
+
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.DisposableEffect
+import androidx.compose.runtime.LaunchedEffect
+import androidx.compose.runtime.snapshotFlow
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.staticCompositionLocalOf
+import androidx.compose.ui.unit.Dp
+import androidx.compose.ui.unit.DpSize
+import androidx.compose.ui.unit.dp
+import androidx.compose.ui.unit.isSpecified
+import androidx.compose.ui.window.WindowPlacement
+import androidx.compose.ui.window.WindowPosition
+import androidx.compose.ui.window.WindowState
+import java.awt.AWTEvent
+import java.awt.GraphicsEnvironment
+import java.awt.Rectangle
+import java.awt.Toolkit
+import java.awt.event.AWTEventListener
+import java.awt.event.MouseEvent
+import java.util.Base64
+import java.util.concurrent.TimeUnit
+import kotlinx.coroutines.delay
+import kotlinx.coroutines.flow.collectLatest
+import kotlin.math.floor
+import kotlin.math.roundToInt
+
+/**
+ * Space left over under the last whole line of a window's scrollback, reported by
+ * MessageScrollback (which already sizes the scrollback itself to whole lines). When a
+ * resize ends, the window is trimmed by this much so the window itself fits whole lines too.
+ */
+class LineGap {
+    @Volatile var gap: Dp = 0.dp
+}
+
+val LocalLineGap = staticCompositionLocalOf<LineGap?> { null }
+
+@Composable
+fun rememberLineGap(): LineGap = remember { LineGap() }
+
+/**
+ * After the mouse is let go at the end of a drag or resize:
+ *  - a move snaps the window's top-left corner to the desktop icon grid
+ *  - a resize trims the window to whole lines of scrollback text (keeping whichever edge
+ *    didn't move in place)
+ * Channel windows are undecorated, so their moves and resizes happen inside the app (the
+ * title-bar drag area and Compose's own edge resizer) and the mouse release reaches wIRC.
+ * wIRC main has a normal Windows frame, whose drags Windows handles itself without telling
+ * the app when the button comes up, so for it ([osFrame] = true) the snap happens once the
+ * window has sat still for a moment instead.
+ */
+@Composable
+fun WindowSnapping(state: WindowState, lineGap: LineGap, osFrame: Boolean = false) {
+    if (osFrame) {
+        LaunchedEffect(state, lineGap) {
+            var settledPos: WindowPosition = state.position
+            var settledSize: DpSize = state.size
+            snapshotFlow { state.position to state.size }.collectLatest {
+                delay(OS_FRAME_SETTLE_MS)
+                afterMoveOrResize(state, lineGap, settledPos, settledSize)
+                settledPos = state.position
+                settledSize = state.size
+            }
+        }
+        return
+    }
+    DisposableEffect(state, lineGap) {
+        var startPos: WindowPosition? = null
+        var startSize: DpSize? = null
+        val listener = AWTEventListener { event ->
+            val e = event as? MouseEvent ?: return@AWTEventListener
+            if (e.button != MouseEvent.BUTTON1) return@AWTEventListener
+            when (e.id) {
+                MouseEvent.MOUSE_PRESSED -> {
+                    startPos = state.position
+                    startSize = state.size
+                }
+                MouseEvent.MOUSE_RELEASED -> {
+                    val p0 = startPos
+                    val s0 = startSize
+                    startPos = null
+                    startSize = null
+                    if (p0 != null && s0 != null) afterMoveOrResize(state, lineGap, p0, s0)
+                }
+            }
+        }
+        Toolkit.getDefaultToolkit().addAWTEventListener(listener, AWTEvent.MOUSE_EVENT_MASK)
+        onDispose { Toolkit.getDefaultToolkit().removeAWTEventListener(listener) }
+    }
+}
+
+// How long wIRC main has to sit still after a move/resize before it snaps
+private const val OS_FRAME_SETTLE_MS = 400L
+
+private fun afterMoveOrResize(state: WindowState, lineGap: LineGap, p0: WindowPosition, s0: DpSize) {
+    if (state.isMinimized || state.placement != WindowPlacement.Floating) return
+    val pos = state.position as? WindowPosition.Absolute ?: return
+    val size = state.size
+    if (!size.isSpecified || !s0.isSpecified) return
+    val start = p0 as? WindowPosition.Absolute
+
+    val resized = (size.width - s0.width).value.let { it > 0.5f || it < -0.5f } ||
+        (size.height - s0.height).value.let { it > 0.5f || it < -0.5f }
+
+    if (resized) {
+        val gap = lineGap.gap
+        if (gap > 0.5.dp && size.height - gap >= 120.dp) {
+            // Dragged the top edge (top moved, bottom stayed): keep the bottom where it is
+            val fromTop = start != null && (pos.y - start.y).value.let { it > 0.5f || it < -0.5f } &&
+                ((pos.y + size.height) - (start.y + s0.height)).value.let { it < 0.5f && it > -0.5f }
+            state.size = DpSize(size.width, size.height - gap)
+            if (fromTop) state.position = WindowPosition.Absolute(pos.x, pos.y + gap)
+        }
+        return
+    }
+
+    if (start == null || (start.x == pos.x && start.y == pos.y)) return
+    val (sx, sy) = DesktopGrid.spacing() ?: return
+    val area = workAreaAt(pos.x.value, pos.y.value)
+    val x = area.x + ((pos.x.value - area.x) / sx).roundToInt() * sx
+    val y = area.y + ((pos.y.value - area.y) / sy).roundToInt() * sy
+    if (x != pos.x.value || y != pos.y.value) state.position = WindowPosition.Absolute(x.dp, y.dp)
+}
+
+// The usable area (taskbar excluded) of the screen the window's corner is on, in the same
+// logical units as WindowState positions.
+private fun workAreaAt(x: Float, y: Float): Rectangle = try {
+    val ge = GraphicsEnvironment.getLocalGraphicsEnvironment()
+    val config = ge.screenDevices.map { it.defaultConfiguration }
+        .firstOrNull { it.bounds.contains(x.toInt(), y.toInt()) } ?: ge.defaultScreenDevice.defaultConfiguration
+    val b = config.bounds
+    val i = Toolkit.getDefaultToolkit().getScreenInsets(config)
+    Rectangle(b.x + i.left, b.y + i.top, b.width - i.left - i.right, b.height - i.top - i.bottom)
+} catch (e: Exception) {
+    Rectangle(0, 0, 1280, 720)
+}
+
+/**
+ * The desktop icon grid's spacing, read from the desktop's own icon view (so it follows the
+ * icon size and spacing Windows is really using), falling back to the system icon spacing.
+ * Java can't call Windows directly without extra libraries, so a hidden PowerShell asks once
+ * at startup, in the background; snapping just skips until the answer is in.
+ */
+object DesktopGrid {
+    @Volatile private var cached: Pair<Float, Float>? = null
+    @Volatile private var started = false
+
+    fun spacing(): Pair<Float, Float>? {
+        if (!started) refreshAsync()
+        return cached
+    }
+
+    @Synchronized
+    fun refreshAsync() {
+        if (started) return
+        started = true
+        Thread {
+            try {
+                val script = """
+                    Add-Type -TypeDefinition @'
+                    using System; using System.Runtime.InteropServices;
+                    public static class WircGrid {
+                      [DllImport("user32.dll", CharSet=CharSet.Unicode)] static extern IntPtr FindWindow(string c, string n);
+                      [DllImport("user32.dll", CharSet=CharSet.Unicode)] static extern IntPtr FindWindowEx(IntPtr p, IntPtr a, string c, string n);
+                      [DllImport("user32.dll")] static extern IntPtr SendMessage(IntPtr h, int m, IntPtr w, IntPtr l);
+                      [DllImport("user32.dll")] static extern bool SystemParametersInfo(uint a, uint p, out int v, uint i);
+                      public static string Get() {
+                        IntPtr dv = FindWindowEx(FindWindow("Progman", null), IntPtr.Zero, "SHELLDLL_DefView", null);
+                        IntPtr w = IntPtr.Zero;
+                        while (dv == IntPtr.Zero) { w = FindWindowEx(IntPtr.Zero, w, "WorkerW", null); if (w == IntPtr.Zero) break; dv = FindWindowEx(w, IntPtr.Zero, "SHELLDLL_DefView", null); }
+                        IntPtr lv = dv == IntPtr.Zero ? IntPtr.Zero : FindWindowEx(dv, IntPtr.Zero, "SysListView32", null);
+                        if (lv != IntPtr.Zero) { long r = SendMessage(lv, 0x1033, IntPtr.Zero, IntPtr.Zero).ToInt64(); long cx = r & 0xFFFF, cy = (r >> 16) & 0xFFFF; if (cx > 0 && cy > 0) return cx + "," + cy; }
+                        int sx, sy; SystemParametersInfo(0x000D, 0, out sx, 0); SystemParametersInfo(0x0018, 0, out sy, 0);
+                        return sx + "," + sy;
+                      }
+                    }
+                    '@
+                    [WircGrid]::Get()
+                """.trimIndent()
+                val encoded = Base64.getEncoder().encodeToString(script.toByteArray(Charsets.UTF_16LE))
+                val proc = ProcessBuilder("powershell.exe", "-NoProfile", "-NonInteractive", "-EncodedCommand", encoded)
+                    .redirectErrorStream(true).start()
+                val out = proc.inputStream.bufferedReader().readText()
+                proc.waitFor(30, TimeUnit.SECONDS)
+                val m = Regex("""(\d+),(\d+)""").findAll(out).lastOrNull() ?: return@Thread
+                val px = m.groupValues[1].toFloat()
+                val py = m.groupValues[2].toFloat()
+                // Physical pixels at the primary screen's scaling -> the logical units windows use
+                val scale = try {
+                    GraphicsEnvironment.getLocalGraphicsEnvironment().defaultScreenDevice.defaultConfiguration.defaultTransform.scaleX.toFloat()
+                } catch (e: Exception) { 1f }.coerceAtLeast(0.5f)
+                if (px > 8 && py > 8) cached = (px / scale) to (py / scale)
+            } catch (e: Exception) {
+                // No grid info: windows just don't snap to it
+            }
+        }.apply { isDaemon = true; name = "wIRC desktop grid" }.start()
+    }
+}
+
+/** Whole lines that fit in [height] at [lineHeight], with a little slack for rounding. */
+internal fun wholeLines(height: Dp, lineHeight: Dp): Int =
+    floor((height.value + 0.5f) / lineHeight.value).toInt().coerceAtLeast(1)