[Crashlytics] io.github.stozo04.openloop.ui.components.TrimFilmstripControlsKt$FilmstripTrimSelector$1$14$1.invoke$lambda$3

[stozo04]

Automated triage — a new fatal crash was reported by Firebase Crashlytics.

• Crashlytics-Issue-ID: 7169b499fee6554684dba69b1ae1a8f0
• Title: io.github.stozo04.openloop.ui.components.TrimFilmstripControlsKt$FilmstripTrimSelector$1$14$1.invoke$lambda$3
• Subtitle: java.lang.IllegalArgumentException - Cannot coerce value to an empty range: maximum 335 is less than minimum 400.
• First seen app version: 1.0.27
• Console: https://console.firebase.google.com/project/openloop-8c266/crashlytics/app/android:io.github.stozo04.openloop/issues/7169b499fee6554684dba69b1ae1a8f0

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@claude please triage this crash. Use the Firebase MCP Crashlytics tools to fetch the
stacktrace and sample events for issue 7169b499fee6554684dba69b1ae1a8f0, consult docs/lessons_learned/,
and post a root-cause comment. If you can point to a specific cause in the code, open a
draft PR with a minimal fix per docs/DEFINITION_OF_DONE.md (note CI could not run
the emulator). Otherwise label needs-human and explain. Never auto-merge.

[claude]

Root-cause analysis

Firebase MCP note: The crashlytics_get_issue and crashlytics_list_events API calls returned 404 (experimental endpoint). All analysis below is derived from the issue subtitle, the crash class name, and the source code.

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Failing stack frame

This de-obfuscates to the END-handle drag branch inside the detectDragGestures lambda in FilmstripTrimSelector (and mirrors in the accessibility setProgress callback for the same handle), in:

app/src/main/java/io/github/stozo04/openloop/ui/components/TrimFilmstripControls.kt

Exception

java.lang.IllegalArgumentException: Cannot coerce value to an empty range:
  maximum 335 is less than minimum 400.

Most likely cause

FilmstripTrimSelector clamps a dragged position into the legal trim window with:

// END handle drag (line ~472)
val clamped = targetMs.coerceIn(curStartMs + minGapMs, durationMs)

// END handle accessibility callback (line ~409)
val clamped = target.coerceIn(startMs + minGapMs, durationMs)

minGapMs = MIN_TRIM_DURATION.inWholeMilliseconds = 400.

When durationMs = 335 (the clip is shorter than the minimum trim window), coerceIn(400, 335) is an inverted range. Kotlin's Long.coerceIn throws IllegalArgumentException on inverted ranges instead of silently clamping — producing exactly the observed error text.

The symmetric bug exists on the START handle:
coerceIn(0L, endMs - minGapMs) → coerceIn(0L, -65L) would give a different message but is also broken.

How a sub-400 ms clip reaches the Trim screen

Neither the recording-finalization path (VM line ~394) nor the gallery-import path (VM line ~573) enforces a minimum-duration floor before setting _uiState.value = OpenLoopUiState.Trim. A very short tap-and-release (e.g. a 335 ms burst) passes straight through to the Trim screen. The NEXT button is correctly disabled there (trimValid check at TrimScreen.kt:154), but the handles still respond to touch and accessibility events — crashing before any guard fires.

Files involved

File	Issue
ui/components/TrimFilmstripControls.kt	4 unguarded coerceIn calls with arithmetically-derived bounds
ui/OpenLoopViewModel.kt	Recording and import entry points lack a minimum-duration gate

Fix (implemented in draft PR)

Guard each coerceIn bound before the call so the range is never inverted, regardless of clip length:

// END handle — was: coerceIn(curStartMs + minGapMs, durationMs)
val minMs = (curStartMs + minGapMs).coerceAtMost(durationMs)
val clamped = targetMs.coerceIn(minMs, durationMs)

// START handle — was: coerceIn(0L, curEndMs - minGapMs)
val maxMs = (curEndMs - minGapMs).coerceAtLeast(0L)
val clamped = targetMs.coerceIn(0L, maxMs)

When the clip is shorter than MIN_TRIM_DURATION, both handles become immovable (start pinned to 0, end pinned to durationMs) — which is correct UX since NEXT is already disabled. Lesson 025 added to docs/lessons_learned/.