Auto commit (MindMachine) Mon Apr 13 08:01:01 PM CDT 2026

app/src/main/java/com/mindmachine/mvp/MainActivity.kt

@@ -18,6 +18,7 @@ import androidx.activity.compose.setContent
 import androidx.activity.viewModels
 import androidx.compose.foundation.background
 import solutions.tretter.mindmachine.session.DurationSliderCard
+import solutions.tretter.mindmachine.session.FlashSequenceEditor
 import solutions.tretter.mindmachine.session.SetupTimelineEditor
 import androidx.compose.foundation.clickable
 import androidx.compose.foundation.gestures.detectTapGestures
@@ -519,13 +520,10 @@ fun SetupScreen(
             onCurveGranularityChanged = vm::setCurveGranularitySec,
         )
 
-        Row(verticalAlignment = Alignment.CenterVertically) {
+        FlashSequenceEditor(
-            Checkbox(
+            sequence = ui.timeline.flashSequence,
-                checked = ui.config.monochromeFlashMode,
+            onSequenceChanged = { sequence -> vm.updateTimeline(ui.timeline.withFlashSequence(sequence)) },
-                onCheckedChange = vm::setMonochromeFlashMode,
+        )
-            )
-            Text("Use black/white flashes for this session", color = MaterialTheme.colorScheme.onBackground)
-        }
 
         Row(horizontalArrangement = Arrangement.spacedBy(8.dp), modifier = Modifier.fillMaxWidth()) {
             if (hasUnsavedChanges) {
@@ -653,11 +651,13 @@ fun ActiveSessionScreen(vm: MainViewModel, onFinish: () -> Unit, onBackToEntry:
                     SplitFlashRenderView(ctx).apply {
                         setRunning(ui.runtimeState == RuntimeState.RUNNING)
                         updateIntervals(ui.runtimeParams.flashOnMs, ui.runtimeParams.flashOffMs)
+                        setFlashSequence(ui.config.flashSequence)
                         setMonochrome(ui.config.monochromeFlashMode)
                     }
                 },
                 update = { view ->
                     view.updateIntervals(ui.runtimeParams.flashOnMs, ui.runtimeParams.flashOffMs)
+                    view.setFlashSequence(ui.config.flashSequence)
                     view.setMonochrome(ui.config.monochromeFlashMode)
                     view.setRunning(ui.runtimeState == RuntimeState.RUNNING)
                 }
@@ -868,6 +868,7 @@ private class SplitFlashRenderView(context: Context) : View(context) {
     private var onMs = 167L
     private var offMs = 167L
     private var monochrome = false
+    private var flashSequence = solutions.tretter.mindmachine.session.defaultFlashSequence()
     private var started = false
     private var startUptimeMs = 0L
     private var nextToggleUptimeMs = 0L
@@ -888,11 +889,11 @@ private class SplitFlashRenderView(context: Context) : View(context) {
                 maxLatenessMs = maxOf(maxLatenessMs, latenessMs)
             }
 
-            phase = (phase + 1) % 4
+            phase = (phase + 1) % phaseCount()
             toggleCount += 1
             invalidate()
 
-            val nextDuration = if (phase == 0 || phase == 2) onMs else offMs
+            val nextDuration = if (isVisiblePhase(phase)) onMs else offMs
             nextToggleUptimeMs += nextDuration
 
             val shouldLogToggle = toggleCount <= 20 || latenessMs > framePeriodMs() || toggleCount % 60L == 0L
@@ -911,11 +912,19 @@ private class SplitFlashRenderView(context: Context) : View(context) {
     }
 
     fun updateIntervals(flashOnMs: Int, flashOffMs: Int) {
-        rawOnMs = flashOnMs.coerceIn(50, 2000).toLong()
+        val newRawOnMs = flashOnMs.coerceIn(50, 2000).toLong()
-        rawOffMs = flashOffMs.coerceIn(50, 2000).toLong()
+        val newRawOffMs = flashOffMs.coerceIn(50, 2000).toLong()
         val frameMs = framePeriodMs().coerceAtLeast(1L)
-        onMs = snapToFrameMs(rawOnMs, frameMs)
+        val newOnMs = snapToFrameMs(newRawOnMs, frameMs)
-        offMs = snapToFrameMs(rawOffMs, frameMs)
+        val newOffMs = snapToFrameMs(newRawOffMs, frameMs)
+
+        val changed = newRawOnMs != rawOnMs || newRawOffMs != rawOffMs || newOnMs != onMs || newOffMs != offMs
+        if (!changed) return
+
+        rawOnMs = newRawOnMs
+        rawOffMs = newRawOffMs
+        onMs = newOnMs
+        offMs = newOffMs
 
         if (isRunning) {
             Log.d(
@@ -925,7 +934,14 @@ private class SplitFlashRenderView(context: Context) : View(context) {
         }
 
         if (isRunning && started) {
-            scheduleFromNow()
+            val now = SystemClock.uptimeMillis()
+            val nextDuration = if (isVisiblePhase(phase)) onMs else offMs
+            nextToggleUptimeMs = maxOf(nextToggleUptimeMs, now + 1L)
+            val remaining = (nextToggleUptimeMs - now).coerceAtLeast(1L)
+            if (remaining > nextDuration) {
+                nextToggleUptimeMs = now + nextDuration
+            }
+            scheduleNext()
         }
     }
 
@@ -962,6 +978,16 @@ private class SplitFlashRenderView(context: Context) : View(context) {
         invalidate()
     }
 
+    fun setFlashSequence(sequence: List<solutions.tretter.mindmachine.session.FlashSequenceRow>) {
+        val normalized = sequence.ifEmpty { solutions.tretter.mindmachine.session.defaultFlashSequence() }
+        if (flashSequence == normalized) return
+        flashSequence = normalized
+        if (started) {
+            phase %= phaseCount()
+        }
+        invalidate()
+    }
+
     override fun onDetachedFromWindow() {
         handler.removeCallbacks(toggleRunnable)
         super.onDetachedFromWindow()
@@ -981,24 +1007,35 @@ private class SplitFlashRenderView(context: Context) : View(context) {
         handler.removeCallbacks(toggleRunnable)
         handler.postAtTime(toggleRunnable, nextToggleUptimeMs)
     }
-
+    private fun colorsForPhase(phase: Int): Pair<Int, Int> {
-    private fun scheduleFromNow() {
+        if (!isVisiblePhase(phase)) return Pair(android.graphics.Color.BLACK, android.graphics.Color.BLACK)
-        val now = SystemClock.uptimeMillis()
+        if (monochrome) return Pair(android.graphics.Color.WHITE, android.graphics.Color.WHITE)
-        nextToggleUptimeMs = now + if (phase == 0 || phase == 2) onMs else offMs
+        val row = flashSequence[(phase / 2).mod(flashSequence.size)]
-        scheduleNext()
+        val left = paletteColor(row.leftColor)
+        val right = if (row.splitScreen) paletteColor(row.rightColor) else left
+        return Pair(left, right)
     }
 
-    private fun colorsForPhase(phase: Int): Pair<Int, Int> = when (phase) {
+    private fun phaseName(phase: Int): String {
-        0 -> if (monochrome) Pair(android.graphics.Color.WHITE, android.graphics.Color.WHITE) else Pair(android.graphics.Color.RED, android.graphics.Color.GREEN)
+        if (!isVisiblePhase(phase)) return "BLACK"
-        2 -> if (monochrome) Pair(android.graphics.Color.WHITE, android.graphics.Color.WHITE) else Pair(android.graphics.Color.GREEN, android.graphics.Color.RED)
+        val row = flashSequence[(phase / 2).mod(flashSequence.size)]
-        else -> Pair(android.graphics.Color.BLACK, android.graphics.Color.BLACK)
+        return if (row.splitScreen) {
+            "${row.leftColor.name}_${row.rightColor.name}"
+        } else {
+            row.leftColor.name
+        }
     }
 
-    private fun phaseName(phase: Int): String = when (phase) {
+    private fun isVisiblePhase(phase: Int): Boolean = phase % 2 == 0
-        0 -> "RED_GREEN"
+
-        1 -> "BLACK"
+    private fun phaseCount(): Int = (flashSequence.size.coerceAtLeast(1)) * 2
-        2 -> "GREEN_RED"
+
-        else -> "BLACK"
+    private fun paletteColor(color: solutions.tretter.mindmachine.session.FlashPaletteColor): Int = when (color) {
+        solutions.tretter.mindmachine.session.FlashPaletteColor.BLACK -> android.graphics.Color.BLACK
+        solutions.tretter.mindmachine.session.FlashPaletteColor.RED -> android.graphics.Color.RED
+        solutions.tretter.mindmachine.session.FlashPaletteColor.GREEN -> android.graphics.Color.GREEN
+        solutions.tretter.mindmachine.session.FlashPaletteColor.YELLOW -> android.graphics.Color.YELLOW
+        solutions.tretter.mindmachine.session.FlashPaletteColor.BLUE -> android.graphics.Color.BLUE
     }
 
     private fun refreshRate(): Float = display?.refreshRate?.takeIf { it > 0f } ?: 60f

app/src/main/java/com/mindmachine/mvp/data/UserProgramRepository.kt

@@ -10,6 +10,9 @@ import solutions.tretter.mindmachine.session.TimelinePoint
 import solutions.tretter.mindmachine.session.TIMELINE_DEFAULT_GRANULARITY_SEC
 import solutions.tretter.mindmachine.session.TimelineSelection
 import solutions.tretter.mindmachine.session.TimelineViewport
+import solutions.tretter.mindmachine.session.FlashPaletteColor
+import solutions.tretter.mindmachine.session.FlashSequenceRow
+import solutions.tretter.mindmachine.session.defaultFlashSequence
 import kotlinx.coroutines.flow.Flow
 import kotlinx.coroutines.flow.map
 import org.json.JSONArray
@@ -83,8 +86,10 @@ class UserProgramRepository(private val context: Context) {
         return TimelineEditorState(
             durationSec = o.getInt("durationSec"),
             curveGranularitySec = TimelineEditorState.normalizeGranularitySec(
-                o.optInt("curveGranularitySec", TIMELINE_DEFAULT_GRANULARITY_SEC)
+                o.optInt("curveGranularitySec", TIMELINE_DEFAULT_GRANULARITY_SEC),
+                o.getInt("durationSec")
             ),
+            flashSequence = parseFlashSequence(o.optJSONArray("flashSequence")),
             selection = TimelineSelection(
                 startSec = o.optInt("selectionStartSec", 0),
                 endSec = o.optInt("selectionEndSec", o.getInt("durationSec")),
@@ -115,6 +120,7 @@ class UserProgramRepository(private val context: Context) {
             val timeline = JSONObject()
             timeline.put("durationSec", program.timeline.durationSec)
             timeline.put("curveGranularitySec", program.timeline.curveGranularitySec)
+            timeline.put("flashSequence", flashSequenceArray(program.timeline.flashSequence))
             timeline.put("selectionStartSec", program.timeline.selection.startSec)
             timeline.put("selectionEndSec", program.timeline.selection.endSec)
             timeline.put("viewportStartSec", program.timeline.viewport.startSec)
@@ -138,6 +144,35 @@ class UserProgramRepository(private val context: Context) {
         }
         return arr
     }
+
+    private fun parseFlashSequence(arr: JSONArray?): List<FlashSequenceRow> {
+        if (arr == null || arr.length() == 0) return defaultFlashSequence()
+        return buildList {
+            for (i in 0 until arr.length()) {
+                val row = arr.getJSONObject(i)
+                add(
+                    FlashSequenceRow(
+                        splitScreen = row.optBoolean("splitScreen", true),
+                        leftColor = row.optString("leftColor", FlashPaletteColor.RED.name).let(FlashPaletteColor::valueOf),
+                        rightColor = row.optString("rightColor", FlashPaletteColor.GREEN.name).let(FlashPaletteColor::valueOf),
+                    )
+                )
+            }
+        }.ifEmpty { defaultFlashSequence() }
+    }
+
+    private fun flashSequenceArray(sequence: List<FlashSequenceRow>): JSONArray {
+        val arr = JSONArray()
+        sequence.forEach { row ->
+            arr.put(
+                JSONObject()
+                    .put("splitScreen", row.splitScreen)
+                    .put("leftColor", row.leftColor.name)
+                    .put("rightColor", row.rightColor.name)
+            )
+        }
+        return arr
+    }
 }
 
 data class UserProgramEntity(

app/src/main/java/com/mindmachine/mvp/domain/Models.kt

@@ -1,5 +1,8 @@
 package solutions.tretter.mindmachine.domain
 
+import solutions.tretter.mindmachine.session.FlashSequenceRow
+import solutions.tretter.mindmachine.session.defaultFlashSequence
+
 enum class VisualPattern { FLASH, PULSE }
 enum class SessionMode { AUDIO_VISUAL, AUDIO_ONLY, VISUAL_ONLY }
 enum class RuntimeState { IDLE, COUNTDOWN, RUNNING, PAUSED, INTERRUPTED, COMPLETED, STOPPED, ERROR }
@@ -17,6 +20,7 @@ data class SessionPreset(
     val cautionNote: String,
     val sortOrder: Int,
     val isUserProgram: Boolean = false,
+    val flashSequence: List<FlashSequenceRow> = defaultFlashSequence(),
 )
 
 data class SessionConfig(
@@ -25,6 +29,7 @@ data class SessionConfig(
     val mode: SessionMode,
     val visualPatternType: VisualPattern,
     val flashIntervalMs: Int,
+    val flashSequence: List<FlashSequenceRow> = defaultFlashSequence(),
     val monochromeFlashMode: Boolean = false,
     val intensityPercent: Int,
     val carrierFrequencyHz: Float,
@@ -97,6 +102,7 @@ fun SessionPreset.toConfig(defaultMode: SessionMode = SessionMode.AUDIO_VISUAL)
     mode = defaultMode,
     visualPatternType = visualPatternType,
     flashIntervalMs = flashIntervalMs,
+    flashSequence = flashSequence,
     monochromeFlashMode = false,
     intensityPercent = intensityPercent,
     carrierFrequencyHz = carrierFrequencyHz,

app/src/main/java/com/mindmachine/mvp/session/DurationSliderCard.kt

@@ -18,7 +18,7 @@ import androidx.compose.ui.unit.dp
 import kotlin.math.roundToInt
 
 private const val MIN_DURATION_SEC = 60
-private const val MAX_DURATION_SEC = 8 * 60 * 60
+private const val MAX_DURATION_SEC = 60 * 60
 
 @Composable
 fun DurationSliderCard(
@@ -51,14 +51,15 @@ fun DurationSliderCard(
         Slider(
             value = clamped.toFloat(),
             onValueChange = {
-                val snapped = (it / 60f).roundToInt().coerceIn(1, 8 * 60) * 60
+                val snapped = (it / 60f).roundToInt().coerceIn(1, 60) * 60
                 onDurationSecChanged(snapped)
             },
             valueRange = MIN_DURATION_SEC.toFloat()..MAX_DURATION_SEC.toFloat(),
+            steps = 58,
         )
 
         Text(
-            "Range: 1 minute to 8 hours",
+            "Range: 1 minute to 60 minutes",
             style = MaterialTheme.typography.bodySmall,
             color = MaterialTheme.colorScheme.onSurface.copy(alpha = 0.7f),
         )

app/src/main/java/com/mindmachine/mvp/session/FlashSequence.kt

@@ -0,0 +1,19 @@
+package solutions.tretter.mindmachine.session
+
+enum class FlashPaletteColor {
+    BLACK,
+    RED,
+    GREEN,
+    YELLOW,
+    BLUE,
+}
+
+data class FlashSequenceRow(
+    val splitScreen: Boolean = true,
+    val leftColor: FlashPaletteColor = FlashPaletteColor.RED,
+    val rightColor: FlashPaletteColor = FlashPaletteColor.GREEN,
+)
+
+fun defaultFlashSequence(): List<FlashSequenceRow> = listOf(
+    FlashSequenceRow(splitScreen = true, leftColor = FlashPaletteColor.RED, rightColor = FlashPaletteColor.GREEN)
+)

app/src/main/java/com/mindmachine/mvp/session/FlashSequenceEditor.kt

@@ -0,0 +1,142 @@
+package solutions.tretter.mindmachine.session
+
+import androidx.compose.foundation.background
+import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.Row
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.shape.RoundedCornerShape
+import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.filled.Add
+import androidx.compose.material.icons.filled.Delete
+import androidx.compose.material3.Checkbox
+import androidx.compose.material3.Icon
+import androidx.compose.material3.IconButton
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.OutlinedButton
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.unit.dp
+
+@Composable
+fun FlashSequenceEditor(
+    sequence: List<FlashSequenceRow>,
+    onSequenceChanged: (List<FlashSequenceRow>) -> Unit,
+    modifier: Modifier = Modifier,
+) {
+    val rows = sequence.ifEmpty { defaultFlashSequence() }
+
+    Column(
+        modifier = modifier
+            .fillMaxWidth()
+            .background(MaterialTheme.colorScheme.surface, RoundedCornerShape(12.dp))
+            .padding(12.dp),
+        verticalArrangement = Arrangement.spacedBy(10.dp),
+    ) {
+        Text("Color sequence", style = MaterialTheme.typography.titleMedium, color = MaterialTheme.colorScheme.onSurface)
+        Text(
+            "Each row is one visible color state. Split screen uses separate left/right colors. Non-split rows fill the whole screen with one color.",
+            style = MaterialTheme.typography.bodySmall,
+            color = MaterialTheme.colorScheme.onSurface.copy(alpha = 0.72f),
+        )
+
+        rows.forEachIndexed { index, row ->
+            Row(
+                modifier = Modifier.fillMaxWidth(),
+                verticalAlignment = Alignment.CenterVertically,
+                horizontalArrangement = Arrangement.spacedBy(8.dp),
+            ) {
+                Row(verticalAlignment = Alignment.CenterVertically, modifier = Modifier.weight(1f)) {
+                    Checkbox(
+                        checked = row.splitScreen,
+                        onCheckedChange = { checked ->
+                            onSequenceChanged(rows.toMutableList().also { it[index] = row.copy(splitScreen = checked) })
+                        }
+                    )
+                    Text("Split screen", color = MaterialTheme.colorScheme.onSurface)
+                }
+
+                ColorCycleButton(
+                    label = if (row.splitScreen) "Left" else "Color",
+                    color = row.leftColor,
+                    onClick = {
+                        onSequenceChanged(rows.toMutableList().also {
+                            it[index] = row.copy(leftColor = row.leftColor.next())
+                        })
+                    },
+                    modifier = Modifier.weight(1f),
+                )
+
+                if (row.splitScreen) {
+                    ColorCycleButton(
+                        label = "Right",
+                        color = row.rightColor,
+                        onClick = {
+                            onSequenceChanged(rows.toMutableList().also {
+                                it[index] = row.copy(rightColor = row.rightColor.next())
+                            })
+                        },
+                        modifier = Modifier.weight(1f),
+                    )
+                } else {
+                    Box(modifier = Modifier.weight(1f))
+                }
+
+                IconButton(
+                    onClick = {
+                        onSequenceChanged(rows.filterIndexed { i, _ -> i != index }.ifEmpty { defaultFlashSequence() })
+                    }
+                ) {
+                    Icon(Icons.Default.Delete, contentDescription = "Remove row", tint = MaterialTheme.colorScheme.onSurface)
+                }
+            }
+        }
+
+        OutlinedButton(
+            onClick = { onSequenceChanged(rows + FlashSequenceRow()) },
+            modifier = Modifier.fillMaxWidth(),
+        ) {
+            Icon(Icons.Default.Add, contentDescription = null)
+            Text(" Add color row")
+        }
+    }
+}
+
+@Composable
+private fun ColorCycleButton(
+    label: String,
+    color: FlashPaletteColor,
+    onClick: () -> Unit,
+    modifier: Modifier = Modifier,
+) {
+    OutlinedButton(onClick = onClick, modifier = modifier) {
+        Box(
+            modifier = Modifier
+                .padding(end = 8.dp)
+                .background(color.previewColor(), RoundedCornerShape(6.dp))
+                .padding(horizontal = 10.dp, vertical = 10.dp)
+        )
+        Text("$label: ${color.displayName}")
+    }
+}
+
+private val FlashPaletteColor.displayName: String
+    get() = name.lowercase().replaceFirstChar { it.uppercase() }
+
+private fun FlashPaletteColor.next(): FlashPaletteColor {
+    val values = FlashPaletteColor.entries
+    return values[(ordinal + 1) % values.size]
+}
+
+private fun FlashPaletteColor.previewColor(): Color = when (this) {
+    FlashPaletteColor.BLACK -> Color.Black
+    FlashPaletteColor.RED -> Color(0xFFD32F2F)
+    FlashPaletteColor.GREEN -> Color(0xFF2E7D32)
+    FlashPaletteColor.YELLOW -> Color(0xFFF9A825)
+    FlashPaletteColor.BLUE -> Color(0xFF1565C0)
+}

app/src/main/java/com/mindmachine/mvp/session/MainViewModel.kt

@@ -175,7 +175,7 @@ class MainViewModel(
             val savedSignature = timelineProgramSignature(timeline)
             it.copy(
                 selectedPreset = preset,
-                config = preset.toConfig(SessionMode.AUDIO_VISUAL),
+                config = preset.toConfig(SessionMode.AUDIO_VISUAL).copy(flashSequence = timeline.flashSequence),
                 timeline = timeline,
                 savedProgramName = displayName,
                 savedTimelineSignature = savedSignature,
@@ -237,7 +237,7 @@ class MainViewModel(
                 val savedSignature = timelineProgramSignature(timeline)
                 it.copy(
                     selectedPreset = fallback,
-                    config = fallback.toConfig(SessionMode.AUDIO_VISUAL),
+                    config = fallback.toConfig(SessionMode.AUDIO_VISUAL).copy(flashSequence = timeline.flashSequence),
                     timeline = timeline,
                     savedProgramName = fallback.name,
                     savedTimelineSignature = savedSignature,
@@ -251,7 +251,7 @@ class MainViewModel(
     fun setMode(mode: SessionMode) = _ui.update { it.copy(config = it.config.copy(mode = mode), error = null) }
 
     fun setDurationSec(seconds: Int) = _ui.update {
-        val clamped = seconds.coerceIn(60, 8 * 60 * 60)
+        val clamped = seconds.coerceIn(60, 60 * 60)
         val nextTimeline = it.timeline.setDurationSec(clamped)
         it.copy(
             config = it.config.copy(durationSec = clamped),
@@ -273,7 +273,10 @@ class MainViewModel(
     fun updateTimeline(newState: TimelineEditorState) = _ui.update {
         it.copy(
             timeline = newState,
-            config = it.config.copy(durationSec = newState.durationSec.coerceIn(60, 8 * 60 * 60)),
+            config = it.config.copy(
+                durationSec = newState.durationSec.coerceIn(60, 60 * 60),
+                flashSequence = newState.flashSequence,
+            ),
             hasUnsavedChanges = isDirty(it.selectedPreset.name, newState, it.savedProgramName, it.savedTimelineSignature),
             error = null,
         )
@@ -451,7 +454,10 @@ class MainViewModel(
             val savedSignature = timelineProgramSignature(timeline)
             it.copy(
                 selectedPreset = preset,
-                config = cfg.copy(durationSec = cfg.durationSec.coerceIn(60, 8 * 60 * 60)),
+                config = cfg.copy(
+                    durationSec = cfg.durationSec.coerceIn(60, 60 * 60),
+                    flashSequence = timeline.flashSequence,
+                ),
                 timeline = timeline,
                 savedProgramName = preset.name,
                 savedTimelineSignature = savedSignature,

app/src/main/java/com/mindmachine/mvp/session/SessionValidator.kt

@@ -3,7 +3,7 @@ package solutions.tretter.mindmachine.session
 import solutions.tretter.mindmachine.domain.SessionConfig
 object SessionValidator {
     fun validate(config: SessionConfig): String? {
-        if (config.durationSec !in 60..(8 * 60 * 60)) return "Duration must be 1 minute to 8 hours."
+        if (config.durationSec !in 60..(60 * 60)) return "Duration must be 1 minute to 60 minutes."
         if (config.flashIntervalMs !in 50..2000) return "Flash interval must be 0.05 to 2.00 seconds."
         val carrier = config.carrierFrequencyHz
         if (!carrier.isFinite() || carrier < ParameterRanges.CARRIER_HZ_MIN || carrier > ParameterRanges.CARRIER_HZ_MAX) {

app/src/main/java/com/mindmachine/mvp/session/SetupTimelineEditor.kt

@@ -27,6 +27,9 @@ fun SetupTimelineEditor(
     modifier: Modifier = Modifier,
 ) {
     var local by remember(state) { mutableStateOf(state) }
+    val allowedGranularity = remember(local.durationSec) { TimelineEditorState.allowedGranularitySteps(local.durationSec) }
+    val sliderMin = allowedGranularity.first().toFloat()
+    val sliderMax = allowedGranularity.last().toFloat()
 
     Column(
         modifier = modifier.fillMaxWidth(),
@@ -38,7 +41,7 @@ fun SetupTimelineEditor(
             color = MaterialTheme.colorScheme.onBackground,
         )
         Text(
-            "Adjust curve granularity, then drag dots up/down to shape the session. Pinch to zoom for precision.",
+            "Adjust curve granularity, then drag dots up/down to shape the session. Granularity always divides the full duration evenly.",
             style = MaterialTheme.typography.bodySmall,
             color = MaterialTheme.colorScheme.onBackground.copy(alpha = 0.75f),
         )
@@ -49,22 +52,22 @@ fun SetupTimelineEditor(
             style = MaterialTheme.typography.bodyMedium,
             color = MaterialTheme.colorScheme.onBackground,
         )
-        var granularitySliderValue by remember(state.curveGranularitySec) {
+        var granularitySliderValue by remember(state.curveGranularitySec, state.durationSec) {
             mutableFloatStateOf(state.curveGranularitySec.toFloat())
         }
         Slider(
-            value = granularitySliderValue,
+            value = granularitySliderValue.coerceIn(sliderMin, sliderMax),
             onValueChange = { granularitySliderValue = it },
             onValueChangeFinished = {
-                val snapped = TimelineEditorState.normalizeGranularitySec(granularitySliderValue.roundToInt())
+                val snapped = TimelineEditorState.normalizeGranularitySec(granularitySliderValue.roundToInt(), local.durationSec)
                 if (snapped != local.curveGranularitySec) {
                     local = local.setCurveGranularitySec(snapped).also(onStateChanged)
                     onCurveGranularityChanged(snapped)
                 }
                 granularitySliderValue = local.curveGranularitySec.toFloat()
             },
-            valueRange = TIMELINE_MIN_GRANULARITY_SEC.toFloat()..TIMELINE_MAX_GRANULARITY_SEC.toFloat(),
+            valueRange = sliderMin..sliderMax,
-            steps = ((TIMELINE_MAX_GRANULARITY_SEC - TIMELINE_MIN_GRANULARITY_SEC) / 5) - 1,
+            steps = max(0, allowedGranularity.size - 2),
         )
 
         TimelineGraph(

app/src/main/java/com/mindmachine/mvp/session/TimelineEditorState.kt

@@ -1,17 +1,19 @@
 package solutions.tretter.mindmachine.session
 
+import kotlin.math.abs
 import kotlin.math.max
 import kotlin.math.min
 
 private const val MIN_DURATION_SEC = 60
-private const val MAX_DURATION_SEC = 8 * 60 * 60
+private const val MAX_DURATION_SEC = 60 * 60
-const val TIMELINE_MIN_GRANULARITY_SEC = 5
+const val TIMELINE_MIN_GRANULARITY_SEC = 30
-const val TIMELINE_MAX_GRANULARITY_SEC = 300
+const val TIMELINE_MAX_GRANULARITY_SEC = 30 * 60
 const val TIMELINE_DEFAULT_GRANULARITY_SEC = 60
 
 data class TimelineEditorState(
     val durationSec: Int,
     val curveGranularitySec: Int,
+    val flashSequence: List<FlashSequenceRow>,
     val selection: TimelineSelection,
     val viewport: TimelineViewport,
     val activeCurve: ActiveCurve,
@@ -32,11 +34,12 @@ data class TimelineEditorState(
     companion object {
         fun default(durationSec: Int = 20 * 60): TimelineEditorState {
             val dur = snapDuration(durationSec)
-            val granularitySec = TIMELINE_DEFAULT_GRANULARITY_SEC
+            val granularitySec = normalizeGranularitySec(TIMELINE_DEFAULT_GRANULARITY_SEC, dur)
             val initial = TimelineCurve.constant(0.5f, dur, granularitySec)
             return TimelineEditorState(
                 durationSec = dur,
                 curveGranularitySec = granularitySec,
+                flashSequence = defaultFlashSequence(),
                 selection = TimelineSelection(0, dur),
                 viewport = TimelineViewport(
                     startSec = 0f,
@@ -52,11 +55,21 @@ data class TimelineEditorState(
             )
         }
 
-        private fun snapDuration(durationSec: Int): Int =
+        fun snapDuration(durationSec: Int): Int =
             ((durationSec.coerceIn(MIN_DURATION_SEC, MAX_DURATION_SEC) + 30) / 60) * 60
 
-        fun normalizeGranularitySec(granularitySec: Int): Int =
+        fun allowedGranularitySteps(durationSec: Int): List<Int> {
-            ((granularitySec.coerceIn(TIMELINE_MIN_GRANULARITY_SEC, TIMELINE_MAX_GRANULARITY_SEC) + 2) / 5) * 5
+            val duration = snapDuration(durationSec)
+            val maxStep = min(TIMELINE_MAX_GRANULARITY_SEC, duration)
+            return (TIMELINE_MIN_GRANULARITY_SEC..maxStep step TIMELINE_MIN_GRANULARITY_SEC)
+                .filter { duration % it == 0 }
+                .ifEmpty { listOf(duration) }
+        }
+
+        fun normalizeGranularitySec(granularitySec: Int, durationSec: Int): Int {
+            val allowed = allowedGranularitySteps(durationSec)
+            return allowed.minByOrNull { abs(it - granularitySec) } ?: allowed.first()
+        }
     }
 
     fun curveFor(id: ActiveCurve): TimelineCurve = when (id) {
@@ -76,35 +89,45 @@ data class TimelineEditorState(
         }
     }
 
+    fun withFlashSequence(sequence: List<FlashSequenceRow>): TimelineEditorState =
+        copy(flashSequence = sequence.ifEmpty { defaultFlashSequence() })
+
     fun extendDurationTo(atLeastSec: Int): TimelineEditorState {
-        val newDur = ((atLeastSec.coerceIn(MIN_DURATION_SEC, MAX_DURATION_SEC) + 30) / 60) * 60
+        val newDur = snapDuration(atLeastSec)
         if (newDur <= durationSec) return this
 
+        val normalizedGranularity = normalizeGranularitySec(curveGranularitySec, newDur)
         return copy(
             durationSec = newDur,
+            curveGranularitySec = normalizedGranularity,
             selection = selection.copy(endSec = max(selection.endSec, newDur)),
-            visualLeft = visualLeft.extendTo(newDur, curveGranularitySec),
+            visualLeft = visualLeft.extendTo(newDur, normalizedGranularity),
-            visualRight = visualRight.extendTo(newDur, curveGranularitySec),
+            visualRight = visualRight.extendTo(newDur, normalizedGranularity),
-            audioLeft = audioLeft.extendTo(newDur, curveGranularitySec),
+            audioLeft = audioLeft.extendTo(newDur, normalizedGranularity),
-            audioRight = audioRight.extendTo(newDur, curveGranularitySec),
+            audioRight = audioRight.extendTo(newDur, normalizedGranularity),
         )
     }
 
     fun setDurationSec(newDurationSec: Int): TimelineEditorState {
-        val clamped = ((newDurationSec.coerceIn(MIN_DURATION_SEC, MAX_DURATION_SEC) + 30) / 60) * 60
+        val clamped = snapDuration(newDurationSec)
         if (clamped == durationSec) return this
+        val normalizedGranularity = normalizeGranularitySec(curveGranularitySec, clamped)
 
         return if (clamped > durationSec) {
-            extendDurationTo(clamped).copy(selection = selection.copy(startSec = 0, endSec = clamped))
+            extendDurationTo(clamped).copy(
+                curveGranularitySec = normalizedGranularity,
+                selection = selection.copy(startSec = 0, endSec = clamped),
+            )
         } else {
             val newViewport = viewport.copy(startSec = viewport.startSec.coerceAtMost(clamped.toFloat()))
             copy(
                 durationSec = clamped,
+                curveGranularitySec = normalizedGranularity,
                 selection = TimelineSelection(0, clamped),
-                visualLeft = visualLeft.trimTo(clamped, curveGranularitySec),
+                visualLeft = visualLeft.trimTo(clamped, normalizedGranularity),
-                visualRight = visualRight.trimTo(clamped, curveGranularitySec),
+                visualRight = visualRight.trimTo(clamped, normalizedGranularity),
-                audioLeft = audioLeft.trimTo(clamped, curveGranularitySec),
+                audioLeft = audioLeft.trimTo(clamped, normalizedGranularity),
-                audioRight = audioRight.trimTo(clamped, curveGranularitySec),
+                audioRight = audioRight.trimTo(clamped, normalizedGranularity),
                 viewport = newViewport,
                 playheadSec = playheadSec.coerceIn(0f, clamped.toFloat()),
             )
@@ -112,7 +135,7 @@ data class TimelineEditorState(
     }
 
     fun setCurveGranularitySec(newGranularitySec: Int): TimelineEditorState {
-        val normalized = normalizeGranularitySec(newGranularitySec)
+        val normalized = normalizeGranularitySec(newGranularitySec, durationSec)
         if (normalized == curveGranularitySec) return this
 
         return copy(
@@ -191,7 +214,7 @@ data class TimelineCurve(
     companion object {
         fun constant(value01: Float, durationSec: Int, granularitySec: Int = TIMELINE_DEFAULT_GRANULARITY_SEC): TimelineCurve {
             val v = value01.coerceIn(0f, 1f)
-            val stepSec = TimelineEditorState.normalizeGranularitySec(granularitySec)
+            val stepSec = TimelineEditorState.normalizeGranularitySec(granularitySec, durationSec)
             return TimelineCurve(
                 points = (0..durationSec step stepSec).map { TimelinePoint(it, v) }
             )
@@ -214,8 +237,8 @@ data class TimelineCurve(
     }
 
     fun ensureTimelinePoints(durationSec: Int, granularitySec: Int): TimelineCurve {
-        val snappedDuration = ((durationSec.coerceIn(MIN_DURATION_SEC, MAX_DURATION_SEC) + 30) / 60) * 60
+        val snappedDuration = TimelineEditorState.snapDuration(durationSec)
-        val stepSec = TimelineEditorState.normalizeGranularitySec(granularitySec)
+        val stepSec = TimelineEditorState.normalizeGranularitySec(granularitySec, snappedDuration)
         val normalized = (0..snappedDuration step stepSec).map { tSec ->
             TimelinePoint(tSec, valueAt(tSec.toFloat()))
         }
@@ -236,7 +259,6 @@ data class TimelineCurve(
         if (index !in points.indices) return this
         val v = (1f - (newY / heightPx)).coerceIn(0f, 1f)
         val updated = points.toMutableList()
-        // Update the dragged point and all points after it (same or later time)
         for (i in index until updated.size) {
             updated[i] = updated[i].copy(value01 = v)
         }

app/src/main/java/com/mindmachine/mvp/session/TimelineModel.kt

@@ -84,6 +84,7 @@ data class TimelineModel(
             mode = mode,
             visualPatternType = preset.visualPatternType,
             flashIntervalMs = flashIntervalMs,
+            flashSequence = preset.flashSequence,
             monochromeFlashMode = false,
             intensityPercent = preset.intensityPercent,
             carrierFrequencyHz = carrier,

app/src/main/java/com/mindmachine/mvp/session/TimelineProgramFactory.kt

@@ -48,6 +48,7 @@ object TimelineProgramFactory {
             cautionNote = "Stop if discomfort occurs.",
             sortOrder = sortOrder,
             isUserProgram = isUserProgram,
+            flashSequence = timeline.flashSequence,
         )
     }
 
@@ -74,6 +75,7 @@ object TimelineProgramFactory {
         return TimelineEditorState(
             durationSec = dur,
             curveGranularitySec = TIMELINE_DEFAULT_GRANULARITY_SEC,
+            flashSequence = preset.flashSequence,
             selection = TimelineSelection(0, dur),
             viewport = TimelineViewport(startSec = 0f, secondsPerScreen = minOf(10f * 60f, dur.toFloat())),
             activeCurve = TimelineEditorState.ActiveCurve.VISUAL_LEFT,
@@ -124,6 +126,7 @@ object TimelineProgramFactory {
         return TimelineEditorState(
             durationSec = durationSec,
             curveGranularitySec = TIMELINE_DEFAULT_GRANULARITY_SEC,
+            flashSequence = defaultFlashSequence(),
             selection = TimelineSelection(0, durationSec),
             viewport = TimelineViewport(startSec = 0f, secondsPerScreen = minOf(10f * 60f, durationSec.toFloat())),
             activeCurve = TimelineEditorState.ActiveCurve.VISUAL_LEFT,