Trim the drag copy's layout note (#267)

The copy always draws the range but was budgeting height for the title
first, so a block too short to have shown either — Day hands its whole
height to the title there, and passed that as the lines it drew — spilled
text past a chip nothing clips.

The copy now pays for the range first and gives the title what of its
lines still fit, and the blocks report the lines they actually drew.
The 2.dp text inset the three of them each spelled out is now a constant.

app/src/main/java/de/jeanlucmakiola/calendula/ui/common/BlockPlacement.kt

@@ -33,6 +33,9 @@ val BLOCK_OUTER_INSET = 1.dp
 /** Padding between a timed block's edge and its text. */
 val BLOCK_TEXT_PADDING = 4.dp
 
+/** The same, above and below — what a block's height has to pay before any text. */
+val BLOCK_TEXT_INSET = 2.dp
+
 /** Most lines a time label may wrap over before it is worth more than a title line. */
 const val MAX_TIME_LINES = 2
 
@@ -61,6 +64,33 @@ fun blockTextLines(text: String, style: TextStyle, textWidth: Dp, max: Int): Int
     }
 }
 
+/**
+ * Lines the time label may take at [textWidth], out of the [spare] height left
+ * once the title and the label's own first line are paid for.
+ *
+ * A week column is narrower than a "09:30–11:00" range, so the label takes a
+ * second line rather than lose its end — but only out of a line the title
+ * measured itself as not needing, never one it would have filled.
+ */
+@Composable
+fun blockTimeLines(label: String, textWidth: Dp, spare: Dp): Int {
+    val timeLineHeight = with(LocalDensity.current) {
+        MaterialTheme.typography.labelSmall.lineHeight.toDp()
+    }
+    return if (spare >= timeLineHeight) {
+        blockTextLines(
+            text = label,
+            // The style it is drawn in, or the budget measures a line the label
+            // never uses (#219).
+            style = MaterialTheme.typography.labelSmall.asEventTime(),
+            textWidth = textWidth,
+            max = MAX_TIME_LINES,
+        )
+    } else {
+        1
+    }
+}
+
 /**
  * A timed block's title, over at most [maxLines].
  *

app/src/main/java/de/jeanlucmakiola/calendula/ui/common/TimelineDrag.kt

@@ -81,6 +81,13 @@ data class TimelineDrag(
     val eventSpanMin: Int,
     /** The event as the grid would draw it, one piece per day column it covers. */
     val pieces: List<TimelineDragPiece>,
+    /**
+     * Lines the block the finger picked up drew its title over, zero for one too
+     * short to have drawn it at all. The floating copy is that block's size, so
+     * it has to spend its height the same way or the text re-wraps under the
+     * finger and snaps back on drop (#267).
+     */
+    val titleLines: Int,
     /**
      * True when [pieces] is only [edgeDragSlice]'s stand-in — the event has left
      * every column this timeline shows. A hint under the finger, not where the
@@ -311,6 +318,9 @@ class TimelineDragController {
      */
     private var clipOffsetMin = 0
 
+    /** What the picked-up block drew its title over — see [TimelineDrag.titleLines]. */
+    private var titleLines = 0
+
     /**
      * The slot the block already occupied when it was picked up — not the same
      * as its start, since the target snaps to the grid (09:07 lifts to 09:00).
@@ -320,11 +330,13 @@ class TimelineDragController {
     fun begin(
         block: TimedBlock,
         clipOffsetMin: Int,
+        titleLines: Int,
         pointerInRoot: Offset,
         blockInRoot: Offset,
     ) {
         source = block
         this.clipOffsetMin = clipOffsetMin
+        this.titleLines = titleLines
         settling = null
         isDragging = true
         liftedInstanceId = block.event.instanceId
@@ -343,6 +355,7 @@ class TimelineDragController {
     fun cancel() {
         source = null
         clipOffsetMin = 0
+        titleLines = 0
         isDragging = false
         liftedInstanceId = null
         originSlot = null
@@ -465,6 +478,7 @@ class TimelineDragController {
             startMin = startMin,
             eventStartMin = eventStartMin,
             eventSpanMin = eventSpan,
+            titleLines = titleLines,
             // Bounded to the columns this timeline actually shows: a day it
             // doesn't has no piece to draw. The write is unaffected.
             pieces = slices
@@ -677,6 +691,7 @@ fun TimelineDragOverlay(controller: TimelineDragController, modifier: Modifier =
                 lift = lift,
                 alpha = copyAlpha,
                 title = title,
+                titleLines = drag.titleLines,
                 // Once for the whole event: repeated, it would name it per day.
                 label = label.takeIf { index == labelled },
             )
@@ -696,9 +711,28 @@ private fun DragCopy(
     lift: Float,
     alpha: Float,
     title: String,
+    titleLines: Int,
     label: String?,
 ) {
     val density = LocalDensity.current
+    val width = with(density) { sizePx.width.toDp() }
+    val height = with(density) { sizePx.height.toDp() }
+    val textWidth = width - (BLOCK_OUTER_INSET + BLOCK_TEXT_PADDING) * 2
+    val titleLineHeight = with(density) {
+        MaterialTheme.typography.labelMedium.lineHeight.toDp()
+    }
+    val timeLineHeight = with(density) {
+        MaterialTheme.typography.labelSmall.lineHeight.toDp()
+    }
+    // The block's size, spent the block's way, so nothing reflows under the
+    // finger (#267) — but the range is paid for first, since it may be showing
+    // where a block too short for it will land, and nothing clips the overrun.
+    val available = height - BLOCK_TEXT_INSET * 2
+    val reserved = if (label == null) 0.dp else timeLineHeight
+    val titleBudget = ((available - reserved) / titleLineHeight).toInt().coerceAtLeast(0)
+    val lines = titleLines.coerceAtMost(titleBudget)
+    val spare = available - titleLineHeight * lines - reserved
+    val timeMaxLines = if (label == null) 1 else blockTimeLines(label, textWidth, spare)
     Box(
         modifier = Modifier
             // Absolute: these are root coordinates, and the direction-aware
@@ -709,10 +743,7 @@ private fun DragCopy(
                     (topLeftInRoot.y - overlayOrigin.y).roundToInt(),
                 )
             }
-            .size(
+            .size(width = width, height = height)
-                width = with(density) { sizePx.width.toDp() },
-                height = with(density) { sizePx.height.toDp() },
-            )
             .padding(horizontal = BLOCK_OUTER_INSET)
             .graphicsLayer {
                 scaleX = 1f + 0.02f * lift
@@ -723,28 +754,28 @@ private fun DragCopy(
                 clip = false
             }
             .eventSurface(paint, shape, cuts)
-            .padding(horizontal = BLOCK_TEXT_PADDING, vertical = 2.dp),
+            .padding(horizontal = BLOCK_TEXT_PADDING, vertical = BLOCK_TEXT_INSET),
     ) {
         Column {
-            val titleOverflow = eventTitleOverflow()
+            if (lines > 0) {
-            Text(
+                BlockTitle(
-                text = title,
+                    title = title,
-                style = MaterialTheme.typography.labelMedium,
+                    maxLines = lines,
-                maxLines = 1,
+                    textWidth = textWidth,
-                overflow = titleOverflow.overflow,
+                    color = paint.titleInk,
-                softWrap = titleOverflow.softWrap,
+                    textDecoration = paint.decoration,
-                color = paint.titleInk,
+                    fontWeight = paint.titleWeight,
-                fontWeight = paint.titleWeight,
+                )
-                textDecoration = paint.decoration,
+            }
-            )
             if (label != null) {
+                val overflow = eventTitleOverflow(singleLine = timeMaxLines == 1)
                 Text(
                     text = label,
                     // As the block it lifted off sets its own time (#219).
                     style = MaterialTheme.typography.labelSmall.asEventTime(),
-                    maxLines = 1,
+                    maxLines = timeMaxLines,
-                    overflow = titleOverflow.overflow,
+                    overflow = overflow.overflow,
-                    softWrap = titleOverflow.softWrap,
+                    softWrap = overflow.softWrap,
                     color = paint.secondaryInk,
                 )
             }

app/src/main/java/de/jeanlucmakiola/calendula/ui/day/DayScreen.kt

@@ -83,10 +83,10 @@ import de.jeanlucmakiola.calendula.ui.common.CalendarView
 import de.jeanlucmakiola.calendula.ui.common.IMPLEMENTED_VIEWS
 import de.jeanlucmakiola.calendula.ui.common.BLOCK_OUTER_INSET
 import de.jeanlucmakiola.calendula.ui.common.BLOCK_TEXT_PADDING
+import de.jeanlucmakiola.calendula.ui.common.BLOCK_TEXT_INSET
 import de.jeanlucmakiola.calendula.ui.common.BlockTimeLabel
 import de.jeanlucmakiola.calendula.ui.common.BlockTitle
-import de.jeanlucmakiola.calendula.ui.common.MAX_TIME_LINES
+import de.jeanlucmakiola.calendula.ui.common.blockTimeLines
-import de.jeanlucmakiola.calendula.ui.common.blockTextLines
 import de.jeanlucmakiola.calendula.ui.common.animatedBlockPlacement
 import de.jeanlucmakiola.calendula.ui.common.ghostAlpha
 import de.jeanlucmakiola.calendula.ui.common.LocalEventMove
@@ -120,7 +120,6 @@ import de.jeanlucmakiola.calendula.ui.common.LocalUse24HourFormat
 import de.jeanlucmakiola.calendula.ui.common.LocalShowHourLines
 import de.jeanlucmakiola.calendula.ui.common.LocalTimelineZoom
 import de.jeanlucmakiola.calendula.ui.common.MIN_EVENT_FRACTION
-import de.jeanlucmakiola.calendula.ui.common.asEventTime
 import de.jeanlucmakiola.calendula.ui.common.hourHeight
 import de.jeanlucmakiola.calendula.ui.common.rememberTimelinePinchZoom
 import de.jeanlucmakiola.calendula.ui.common.formatMinuteOfDay
@@ -738,33 +737,20 @@ private fun EventBlock(
     val timeLineHeight = with(density) {
         MaterialTheme.typography.labelSmall.lineHeight.toDp()
     }
-    // What's left for text once the 2.dp top/bottom padding is paid for. A block
+    // A block that cannot afford both lines spends its space on the title, and
-    // that cannot afford both lines spends its space on the title, and one too
+    // one too short even for that drops the title rather than serving a sliced one.
-    // short even for that drops the title rather than serving a sliced one.
     // Height alone decides: a duration threshold would keep hiding the time on a
     // half-hour block the user has pinched open to three times the room it needs.
-    val available = height - 4.dp
+    val available = height - BLOCK_TEXT_INSET * 2
     val showTime = available >= titleLineHeight + timeLineHeight
     val showTitle = available >= titleLineHeight
     val textWidth = width - (BLOCK_OUTER_INSET + BLOCK_TEXT_PADDING) * 2
     val titleMaxLines = if (showTime) 1 else 2
-    // The range only wraps out of a line the title has not claimed, which on a
+    // On a day column — wide enough for "09:30–11:00" several times over — the
-    // day column — wide enough for "09:30–11:00" several times over — means it
+    // range never needs the second line, until lanes cut the column down.
-    // never does, until lanes cut the column down.
     val spare = available - titleLineHeight * titleMaxLines -
         if (showTime) timeLineHeight else 0.dp
-    val timeMaxLines = if (showTime && spare >= timeLineHeight) {
+    val timeMaxLines = if (showTime) blockTimeLines(timeLabel, textWidth, spare) else 1
-        blockTextLines(
-            text = timeLabel,
-            // The style it is drawn in, or the budget measures a line the label
-            // never uses (#219).
-            style = MaterialTheme.typography.labelSmall.asEventTime(),
-            textWidth = textWidth,
-            max = MAX_TIME_LINES,
-        )
-    } else {
-        1
-    }
     val paint = eventPaint(block.event, dark)
     val zone = remember { TimeZone.currentSystemDefault() }
     val moveAction = eventMoveAction(block.event)
@@ -780,7 +766,13 @@ private fun EventBlock(
         enabled = draggable,
         key = block.event.instanceId,
         onPickUp = { pointer, blockRoot, _ ->
-            dragController.begin(block, clipOffset, pointer, blockRoot)
+            dragController.begin(
+                block = block,
+                clipOffsetMin = clipOffset,
+                titleLines = if (showTitle) titleMaxLines else 0,
+                pointerInRoot = pointer,
+                blockInRoot = blockRoot,
+            )
         },
         onMove = dragController::move,
         onDrop = { dragController.finish()?.let(onDrop) },
@@ -797,7 +789,7 @@ private fun EventBlock(
             // After clickable, so it is the inner node and wins the main pass;
             // the tap still works, since a drag consumes the up.
             .then(dragModifier)
-            .padding(horizontal = BLOCK_TEXT_PADDING, vertical = 2.dp)
+            .padding(horizontal = BLOCK_TEXT_PADDING, vertical = BLOCK_TEXT_INSET)
             .semantics {
                 contentDescription = "$title, $timeLabel"
                 if (moveAction != null) customActions = listOf(moveAction)

app/src/main/java/de/jeanlucmakiola/calendula/ui/week/WeekScreen.kt

@@ -91,10 +91,11 @@ import de.jeanlucmakiola.calendula.ui.common.IMPLEMENTED_VIEWS
 import de.jeanlucmakiola.calendula.ui.common.EventDimAlpha
 import de.jeanlucmakiola.calendula.ui.common.BLOCK_OUTER_INSET
 import de.jeanlucmakiola.calendula.ui.common.BLOCK_TEXT_PADDING
+import de.jeanlucmakiola.calendula.ui.common.BLOCK_TEXT_INSET
 import de.jeanlucmakiola.calendula.ui.common.BlockTimeLabel
 import de.jeanlucmakiola.calendula.ui.common.BlockTitle
-import de.jeanlucmakiola.calendula.ui.common.MAX_TIME_LINES
 import de.jeanlucmakiola.calendula.ui.common.blockTextLines
+import de.jeanlucmakiola.calendula.ui.common.blockTimeLines
 import de.jeanlucmakiola.calendula.ui.common.animatedBlockPlacement
 import de.jeanlucmakiola.calendula.ui.common.ghostAlpha
 import de.jeanlucmakiola.calendula.ui.common.LocalEventMove
@@ -130,7 +131,6 @@ import de.jeanlucmakiola.calendula.ui.common.LocalShowHourLines
 import de.jeanlucmakiola.calendula.ui.common.LocalTimelineZoom
 import de.jeanlucmakiola.calendula.ui.common.MIN_EVENT_FRACTION
 import de.jeanlucmakiola.calendula.ui.common.MIN_TITLE_WRAP_WIDTH
-import de.jeanlucmakiola.calendula.ui.common.asEventTime
 import de.jeanlucmakiola.calendula.ui.common.hourHeight
 import de.jeanlucmakiola.calendula.ui.common.rememberTimelinePinchZoom
 import de.jeanlucmakiola.calendula.ui.common.formatMinuteOfDay
@@ -883,8 +883,7 @@ private fun EventBlock(
     val timeLineHeight = with(density) {
         MaterialTheme.typography.labelSmall.lineHeight.toDp()
     }
-    // What's left for text once the 2.dp top/bottom padding is paid for.
+    val available = height - BLOCK_TEXT_INSET * 2
-    val available = height - 4.dp
     // Only full-width (non-overlapping) blocks that are tall enough show the
     // time. On narrow overlapping columns we drop it so the title can wrap to
     // fill the whole block, mirroring Google Calendar — and a block that cannot
@@ -918,23 +917,9 @@ private fun EventBlock(
             max = titleBudget,
         )
     }
-    // A week column is narrower than a "09:30–11:00" range, so the label takes a
-    // second line rather than lose its end — but only out of a line the title
-    // measured itself as not needing, never one it would have filled.
     val spare = available - titleLineHeight * titleMaxLines -
         if (showTime) timeLineHeight else 0.dp
-    val timeMaxLines = if (showTime && spare >= timeLineHeight) {
+    val timeMaxLines = if (showTime) blockTimeLines(timeLabel, textWidth, spare) else 1
-        blockTextLines(
-            text = timeLabel,
-            // The style it is drawn in, or the budget measures a line the label
-            // never uses (#219).
-            style = MaterialTheme.typography.labelSmall.asEventTime(),
-            textWidth = textWidth,
-            max = MAX_TIME_LINES,
-        )
-    } else {
-        1
-    }
     val dimCutoff = LocalDimCutoff.current
     val dimmed = dimCutoff != null && block.event.hasEnded(dimCutoff)
     val zone = remember { TimeZone.currentSystemDefault() }
@@ -951,7 +936,13 @@ private fun EventBlock(
         enabled = draggable,
         key = block.event.instanceId,
         onPickUp = { pointer, blockRoot, _ ->
-            dragController.begin(block, clipOffset, pointer, blockRoot)
+            dragController.begin(
+                block = block,
+                clipOffsetMin = clipOffset,
+                titleLines = if (showTitle) titleMaxLines else 0,
+                pointerInRoot = pointer,
+                blockInRoot = blockRoot,
+            )
         },
         onMove = dragController::move,
         onDrop = { dragController.finish()?.let(onDrop) },
@@ -968,7 +959,7 @@ private fun EventBlock(
             // After clickable, so it is the inner node and wins the main pass;
             // the tap still works, since a drag consumes the up.
             .then(dragModifier)
-            .padding(horizontal = BLOCK_TEXT_PADDING, vertical = 2.dp)
+            .padding(horizontal = BLOCK_TEXT_PADDING, vertical = BLOCK_TEXT_INSET)
             .semantics {
                 contentDescription = "$title, $timeLabel"
                 if (moveAction != null) customActions = listOf(moveAction)