web(review): confidence-aware date guesser with combined filename + path signals

Refactor suggestDateFromPath to combine multiple signals instead of
trying patterns in priority order:

- Filename Y-M-D corroborated by path Y-M/Y-M-D → HIGH (filename-
  agrees-path). Fixes the case where a Samsung-style 20240226_xxx.jpg
  under 2024/02/ was returning the path-only 2024-02-01.
- Filename Y-M-D with no path signal → HIGH (filename-only).
- 10/13-digit Unix epoch in basename → HIGH (unix-timestamp) —
  covers WeChat (mmexport...) and FB saves.
- Path Y-M-D → HIGH (path-ymd).
- Path Y-M only → MEDIUM (path-ym-default-day, synthesised day=01).
  Sidebar row labels these "(estimated day)" so the user knows.

Filename parser now accepts `.` and space separators (covers macOS
screenshots, manual 2024.02.26 renames). Path parser accepts `.` too.
OriginalName participates as a secondary filename signal when present
and different from the on-disk basename.

Patterns we explicitly DO NOT parse, to avoid silent date flips:
DD-MM-YYYY / MM-DD-YYYY, 2-digit years, bare camera sequence numbers.

Add photoNameAndDir(p) helper next to primaryFile so RightSidebar,
BulkActionBar, photoActions, and gridKeyNav all derive {fileName,
path} the same way — fixes the bug where photo.FileName was
undefined on the single-photo detail endpoint and the basename branch
was being skipped entirely.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

web/src/lib/actions/gridKeyNav.ts

@@ -12,6 +12,7 @@ import {
 } from '$lib/services/photoprism';
 import { acceptDateAndKeep, cachedPhoto } from '$lib/services/photoActions';
 import { suggestDateFromPath } from '$lib/utils/suggestDateFromPath';
+import { photoNameAndDir } from '$lib/types/photoprism';
 import { queryClient } from '$lib/queryClient';
 import { filters } from '$lib/stores/filters.svelte';
 import {
@@ -486,7 +487,10 @@ export function gridKeyNav(node: HTMLElement, params: GridKeyNavParams = {}) {
 					for (const id of ids) {
 						const p = cachedPhoto(id);
 						if (!p) return;
-						if (!suggestDateFromPath({ fileName: p.FileName, path: p.Path })) return;
+						const { fileName, path } = photoNameAndDir(p);
+						if (!suggestDateFromPath({ fileName, originalName: p.OriginalName, path })) {
+							return;
+						}
 					}
 					e.preventDefault();
 					void acceptDateAndKeep(ids);

web/src/lib/components/sidebar/RightSidebar.svelte

@@ -38,7 +38,7 @@
 	import { isAuthenticated } from '$lib/stores/session.svelte';
 	import { push as pushUndo } from '$lib/stores/undo.svelte';
 	import { getMetadataSectionOpen, setMetadataSection } from '$lib/stores/view.svelte';
-	import { primaryFile, type PpPhoto } from '$lib/types/photoprism';
+	import { photoNameAndDir, primaryFile, type PpPhoto } from '$lib/types/photoprism';
 	import { COLOR_SWATCHES } from '$lib/utils/tagGroups';
 	import { suggestDateFromPath } from '$lib/utils/suggestDateFromPath';
 
@@ -139,15 +139,20 @@
 		page.url.pathname === '/review' &&
 			page.url.searchParams.get('tab') === 'stripped_exif'
 	);
-	const dateSuggestion = $derived(
-		suggestDateFromPath({ fileName: photo.FileName, path: photo.Path })
-	);
+	const dateSuggestion = $derived.by(() => {
+		const { fileName, path } = photoNameAndDir(photo);
+		return suggestDateFromPath({
+			fileName,
+			originalName: photo.OriginalName,
+			path
+		});
+	});
 	const showDateSuggestion = $derived(
-		onExifStrippedTab && !!dateSuggestion && dateSuggestion !== takenAt
+		onExifStrippedTab && !!dateSuggestion && dateSuggestion.iso !== takenAt
 	);
 	function applyDateSuggestion() {
 		if (!dateSuggestion) return;
-		takenAt = dateSuggestion;
+		takenAt = dateSuggestion.iso;
 		commitTakenAt();
 	}
 	function commitTakenAt() {
@@ -344,17 +349,23 @@
 			/>
 		</div>
 
-		<!-- Date suggestion derived from the file/folder path. Only shown
-		     on the EXIF Stripped review tab; amber styling marks it as
-		     unconfirmed. Apply writes the value into the date input above
-		     and commits as a manual TakenAt edit. -->
-		{#if showDateSuggestion}
+		<!-- Date suggestion derived from filename / folder signals. Only
+		     shown on the EXIF Stripped review tab; amber styling marks
+		     it as unconfirmed. `(estimated day)` hint appears when the
+		     day was synthesised because only Y-M was available — same
+		     row, just so the user knows that part is fabricated. Apply
+		     writes the value into the date input above and commits as
+		     a manual TakenAt edit. -->
+		{#if showDateSuggestion && dateSuggestion}
 			<div
 				class="flex items-center gap-2 rounded border border-amber-300/70 bg-amber-50/40 px-1.5 py-1 text-[11px] text-amber-700 dark:border-amber-500/40 dark:bg-amber-500/10 dark:text-amber-300"
 			>
 				<Folder class="h-3.5 w-3.5 shrink-0" />
 				<span class="min-w-0 flex-1 truncate">
-					Suggested from path: <span class="font-medium">{dateSuggestion}</span>
+					Suggested from path: <span class="font-medium">{dateSuggestion.iso}</span>
+					{#if dateSuggestion.source === 'path-ym-default-day'}
+						<span class="text-amber-600/80 dark:text-amber-400/70">(estimated day)</span>
+					{/if}
 				</span>
 				<button
 					type="button"

web/src/lib/components/timeline/BulkActionBar.svelte

@@ -15,6 +15,7 @@
 	import { batchEdit } from '$lib/services/batch';
 	import { acceptDateAndKeep, cachedPhoto } from '$lib/services/photoActions';
 	import { suggestDateFromPath } from '$lib/utils/suggestDateFromPath';
+	import { photoNameAndDir } from '$lib/types/photoprism';
 	import {
 		clearBulkToFirst,
 		clearSelection,
@@ -82,7 +83,10 @@
 		for (const id of ids) {
 			const p = cachedPhoto(id);
 			if (!p) return false;
-			if (!suggestDateFromPath({ fileName: p.FileName, path: p.Path })) return false;
+			const { fileName, path } = photoNameAndDir(p);
+			if (!suggestDateFromPath({ fileName, originalName: p.OriginalName, path })) {
+				return false;
+			}
 		}
 		return true;
 	});
@@ -268,13 +272,13 @@
 				     the archive section. Everything else (heap, restore)
 				     is hidden so the choice reads as decisive. -->
 				<button
-					class="inline-flex items-center gap-1 rounded border border-primary/40 bg-primary/10 px-2 py-0.5 text-[11px] text-primary hover:bg-primary/20 disabled:opacity-50"
+					class="inline-flex items-center gap-1 rounded bg-primary px-2 py-0.5 text-[11px] font-medium text-primary-foreground hover:bg-primary/90 disabled:opacity-50"
 					disabled={busy}
 					onclick={onApprove}
 					title="Keep — accept into timeline"
 				>
 					✓ Keep
-					<kbd class="rounded bg-muted px-1 text-[9px] font-medium text-muted-foreground">S</kbd>
+					<kbd class="rounded bg-primary-foreground/15 px-1 text-[9px] font-medium text-primary-foreground/90">S</kbd>
 				</button>
 				{#if allHaveSuggestion}
 					<!-- Visible only when every selected photo has a path-
@@ -292,7 +296,7 @@
 					</button>
 				{/if}
 				<button
-					class="inline-flex items-center gap-1 rounded border border-border px-2 py-0.5 text-[11px] hover:bg-accent disabled:opacity-50"
+					class="inline-flex items-center gap-1 rounded border border-border bg-background px-2 py-0.5 text-[11px] hover:bg-accent disabled:opacity-50"
 					disabled={busy}
 					onclick={onArchive}
 					title="Archive"
@@ -307,13 +311,13 @@
 				     photo is already archived; the destructive styling
 				     reinforces the irreversibility. -->
 				<button
-					class="inline-flex items-center gap-1 rounded border border-primary/40 bg-primary/10 px-2 py-0.5 text-[11px] text-primary hover:bg-primary/20 disabled:opacity-50"
+					class="inline-flex items-center gap-1 rounded bg-primary px-2 py-0.5 text-[11px] font-medium text-primary-foreground hover:bg-primary/90 disabled:opacity-50"
 					disabled={busy}
 					onclick={onRestore}
 					title="Keep — restore to timeline"
 				>
 					✓ Keep
-					<kbd class="rounded bg-muted px-1 text-[9px] font-medium text-muted-foreground">S</kbd>
+					<kbd class="rounded bg-primary-foreground/15 px-1 text-[9px] font-medium text-primary-foreground/90">S</kbd>
 				</button>
 				<button
 					class="inline-flex items-center gap-1 rounded border border-destructive/40 bg-destructive/5 px-2 py-0.5 text-[11px] text-destructive hover:bg-destructive/10 disabled:opacity-50"
@@ -327,13 +331,13 @@
 			{:else}
 				<div class="relative">
 					<button
-						class="inline-flex items-center gap-1 rounded border border-border px-2 py-0.5 text-[11px] hover:bg-accent disabled:opacity-50"
+						class="inline-flex items-center gap-1 rounded bg-primary px-2 py-0.5 text-[11px] font-medium text-primary-foreground hover:bg-primary/90 disabled:opacity-50"
 						disabled={busy}
 						onclick={() => (heapPickerOpen = !heapPickerOpen)}
 						title="Add to heap (S then 1–9 picks a heap)"
 					>
 						＋ Add to heap
-						<kbd class="rounded bg-muted px-1 text-[9px] font-medium text-muted-foreground"
+						<kbd class="rounded bg-primary-foreground/15 px-1 text-[9px] font-medium text-primary-foreground/90"
 							>S&nbsp;N</kbd
 						>
 					</button>
@@ -372,7 +376,7 @@
 					{/if}
 				</div>
 				<button
-					class="inline-flex items-center gap-1 rounded border border-border px-2 py-0.5 text-[11px] hover:bg-accent disabled:opacity-50"
+					class="inline-flex items-center gap-1 rounded border border-border bg-background px-2 py-0.5 text-[11px] hover:bg-accent disabled:opacity-50"
 					disabled={busy}
 					onclick={onArchive}
 					title="Archive"
@@ -382,7 +386,7 @@
 				</button>
 			{/if}
 			<button
-				class="inline-flex items-center gap-1 rounded border border-border px-2 py-0.5 text-[11px] hover:bg-accent"
+				class="inline-flex items-center gap-1 rounded px-2 py-0.5 text-[11px] text-muted-foreground hover:bg-accent hover:text-foreground"
 				onclick={clearAll}
 				title={isBulk ? 'Clear selection' : 'Clear focus'}
 			>

web/src/lib/services/photoActions.ts

@@ -25,7 +25,7 @@ import { queryClient } from '$lib/queryClient';
 import { clearSelection, focusAfter } from '$lib/stores/selection.svelte';
 import { push as pushUndo } from '$lib/stores/undo.svelte';
 import { suggestDateFromPath } from '$lib/utils/suggestDateFromPath';
-import type { PpPhoto } from '$lib/types/photoprism';
+import { photoNameAndDir, type PpPhoto } from '$lib/types/photoprism';
 
 /** Walk every cache that might hold a photo's metadata — timeline list
  *  (flat or infinite), review-groups bucket, per-photo detail — without
@@ -95,9 +95,14 @@ export async function acceptDateAndKeep(uids: string[]): Promise<void> {
 	if (uids.length === 0) return;
 	const { updated, errors } = await batchEdit(uids, async (id) => {
 		const p = cachedPhoto(id);
-		const iso = p ? suggestDateFromPath({ fileName: p.FileName, path: p.Path }) : null;
-		if (p && iso) {
-			await updatePhoto(p, buildTakenAtPatch(`${iso}T00:00:00Z`));
+		if (p) {
+			const { fileName, path } = photoNameAndDir(p);
+			const guess = suggestDateFromPath({
+				fileName,
+				originalName: p.OriginalName,
+				path
+			});
+			if (guess) await updatePhoto(p, buildTakenAtPatch(`${guess.iso}T00:00:00Z`));
 		}
 		await approvePhoto(id);
 		return id;

web/src/lib/types/photoprism.ts

@@ -213,6 +213,23 @@ export interface PpPhotoLabel {
 	Label?: { Slug: string; Name: string };
 }
 
+/**
+ * Split a photo into its basename + directory portion using the
+ * primary file's relative `Name` (`'2024/02/IMG.jpg'` → `{ fileName:
+ * 'IMG.jpg', path: '2024/02' }`). Falls back to `photo.Path` when the
+ * primary file's `Name` lacks a directory prefix — that pairs with the
+ * list-endpoint shape where `Path` is its own field. Shared so date-
+ * suggestion code paths in RightSidebar / photoActions / gridKeyNav
+ * derive inputs the same way regardless of which cache shape they
+ * have on hand (list vs detail).
+ */
+export function photoNameAndDir(p: PpPhoto): { fileName: string; path: string } {
+	const full = primaryFile(p).Name ?? '';
+	const i = full.lastIndexOf('/');
+	if (i < 0) return { fileName: full, path: p.Path ?? '' };
+	return { fileName: full.slice(i + 1), path: full.slice(0, i) };
+}
+
 /**
  * Return the photo's primary file (the one with `Primary: true`) or the
  * first file if no primary marker is set. Falls back to a synthetic entry

web/src/lib/utils/suggestDateFromPath.ts

@@ -1,68 +1,219 @@
 /**
  * Best-effort calendar date guessed from a photo's filename / parent
- * folders. Returns `YYYY-MM-DD`:
- *   - high-confidence when year + month + day are all parseable
- *     (basename or path)
- *   - month-anchored when only year + month appear in the path (day
- *     synthesised to `01` so the value drops cleanly into a date
- *     input; the user reviews + adjusts before committing)
- * Returns `null` for year-only or unparseable inputs.
+ * folders, with a confidence label so the UI can warn the user when
+ * the day is fabricated.
  *
- * Used by the EXIF Stripped review tab to pre-fill the metadata
- * sidebar's date suggestion row.
+ * Conventions we support (no false-positive risk):
+ *   - Samsung / Android stock    20240226_135421.jpg
+ *   - Google Pixel               PXL_20240226_135421.123.jpg
+ *   - WhatsApp                   IMG-20240226-WA0001.jpg
+ *   - Telegram                   photo_2024-02-26_13-54-21.jpg
+ *   - macOS screenshot           Screen Shot 2024-02-26 at 1.54.21 PM.png
+ *   - Android screenshot         Screenshot_20240226-135421.png
+ *   - Manual dot-format          2024.02.26 - title.jpg
+ *   - WeChat                     mmexport1645900000000.jpeg  (13-digit ms)
+ *   - Facebook saves             FB_IMG_1583926812.jpg       (10-digit s)
+ *   - Path forms                 2024/02/26, 2024-02-26, 2024_02_26,
+ *                                2024.02.26, plus Y-M-only 2024/02/
+ *
+ * Conventions we deliberately do NOT parse (locale-ambiguous or no
+ * recoverable signal):
+ *   - DD-MM-YYYY / MM-DD-YYYY    26-02-2024.jpg, 02-26-2024.jpg
+ *   - 2-digit years              24-02-26.jpg
+ *   - Bare sequence numbers      IMG_1234.HEIC, DSC_0123.NEF,
+ *                                GOPR0123.JPG, DJI_0123.JPG
+ *
+ * Used by the EXIF Stripped review tab to surface a date suggestion
+ * row in the metadata sidebar and to power the "Accept date & Keep"
+ * bulk action.
  */
 
 import { isValidISODate } from '$lib/services/photoprism';
 
 interface Input {
-	fileName?: string;
-	path?: string;
+	fileName?: string; // basename, e.g. '20240226_000000_A6D42DF3.jpg'
+	originalName?: string; // optional second filename signal (PpPhoto.OriginalName)
+	path?: string; // directory portion, e.g. '2024/02'
+}
+
+export interface DateGuess {
+	iso: string;
+	confidence: 'high' | 'medium';
+	source:
+		| 'filename-agrees-path'
+		| 'filename-only'
+		| 'unix-timestamp'
+		| 'path-ymd'
+		| 'path-ym-default-day';
+}
+
+interface YMD {
+	y: number;
+	m: number;
+	d: number;
+}
+
+interface YM {
+	y: number;
+	m: number;
 }
 
 function pad2(n: number): string {
 	return n < 10 ? `0${n}` : String(n);
 }
 
-function tryDate(y: number, m: number, d: number): string | null {
+function isoOf(ymd: YMD): string {
+	return `${ymd.y}-${pad2(ymd.m)}-${pad2(ymd.d)}`;
+}
+
+function tryYMD(y: number, m: number, d: number): YMD | null {
 	if (y < 1900 || y > 2100) return null;
 	if (m < 1 || m > 12) return null;
 	if (d < 1 || d > 31) return null;
-	const iso = `${y}-${pad2(m)}-${pad2(d)}`;
-	return isValidISODate(iso) ? iso : null;
+	if (!isValidISODate(`${y}-${pad2(m)}-${pad2(d)}`)) return null;
+	return { y, m, d };
 }
 
-// `YYYY[sep]MM[sep]DD` where `sep` is an optional `-` or `_`. Anchored by
-// non-digit boundaries on both sides so `IMG_20070612_135421.jpg` matches
-// `20070612` cleanly without bleeding into the trailing timestamp.
-const BASENAME_YMD = /(?<!\d)(\d{4})[-_]?(\d{2})[-_]?(\d{2})(?!\d)/;
+function tryYM(y: number, m: number): YM | null {
+	if (y < 1900 || y > 2100) return null;
+	if (m < 1 || m > 12) return null;
+	return { y, m };
+}
 
-// Path Y-M-D first (e.g. `2007/06/12`, `2007-06-12/`). Y-M fallback
-// (`2024/01/`, `Photos/2024-01/inner`) trips when the user only foldered
-// by month — the day defaults to `01` so the field has a sensible
-// pre-filled value rather than nothing.
-const PATH_YMD = /(?<!\d)(\d{4})[-_/](\d{2})[-_/](\d{2})(?!\d)/;
-const PATH_YM = /(?<!\d)(\d{4})[-_/](\d{2})(?!\d)/;
+// `YYYY[sep]MM[sep]DD` for basenames. sep ∈ {nothing, -, _, ., space}. The
+// non-digit lookbehind/ahead keeps a leading prefix like `PXL_` and a
+// trailing time like `_135421` from polluting the match.
+const BASENAME_YMD = /(?<!\d)(\d{4})[-_. ]?(\d{2})[-_. ]?(\d{2})(?!\d)/;
 
-export function suggestDateFromPath(input: Input): string | null {
+// Path Y-M-D and Y-M. Includes `/` for directory separators and `.` for
+// rare dot-organised libraries (`Photos/2024.02/...`).
+const PATH_YMD = /(?<!\d)(\d{4})[-_/.](\d{2})[-_/.](\d{2})(?!\d)/;
+const PATH_YM = /(?<!\d)(\d{4})[-_/.](\d{2})(?!\d)/;
+
+// 10- or 13-digit Unix epoch, anchored. Years widened to [1990, current+1]
+// to dodge accidental matches on phone numbers, hex hashes containing
+// digits, etc. — but 10-digit seconds still has to round-trip into a
+// plausible calendar year before we trust it.
+const BASENAME_EPOCH = /(?<!\d)(\d{10}|\d{13})(?!\d)/;
+
+function parseFilenameYMD(name: string): YMD | null {
+	const m = name.match(BASENAME_YMD);
+	if (!m) return null;
+	return tryYMD(Number(m[1]), Number(m[2]), Number(m[3]));
+}
+
+function parseUnixTimestampInName(name: string): YMD | null {
+	const m = name.match(BASENAME_EPOCH);
+	if (!m) return null;
+	const digits = m[1];
+	const ms = digits.length === 13 ? Number(digits) : Number(digits) * 1000;
+	if (!Number.isFinite(ms)) return null;
+	const d = new Date(ms);
+	if (Number.isNaN(d.getTime())) return null;
+	const y = d.getUTCFullYear();
+	if (y < 1990 || y > new Date().getUTCFullYear() + 1) return null;
+	return tryYMD(y, d.getUTCMonth() + 1, d.getUTCDate());
+}
+
+function parsePathYMD(path: string): YMD | null {
+	const m = path.match(PATH_YMD);
+	if (!m) return null;
+	return tryYMD(Number(m[1]), Number(m[2]), Number(m[3]));
+}
+
+function parsePathYM(path: string): YM | null {
+	const m = path.match(PATH_YM);
+	if (!m) return null;
+	return tryYM(Number(m[1]), Number(m[2]));
+}
+
+function ymdAgreesWithYM(ymd: YMD, ym: YM): boolean {
+	return ymd.y === ym.y && ymd.m === ym.m;
+}
+
+function ymdEqual(a: YMD, b: YMD): boolean {
+	return a.y === b.y && a.m === b.m && a.d === b.d;
+}
+
+/** Pick the filename-derived YMD that best aligns with the path. When
+ *  both `fileName` and `originalName` yield candidates, prefer the one
+ *  that matches the path's year+month; ties fall back to `fileName`. */
+function pickFilenameYMD(
+	fileName: string,
+	originalName: string,
+	pathYM: YM | null
+): YMD | null {
+	const candidates: YMD[] = [];
+	const a = parseFilenameYMD(fileName);
+	if (a) candidates.push(a);
+	if (originalName && originalName !== fileName) {
+		const b = parseFilenameYMD(originalName);
+		if (b && !candidates.some((c) => ymdEqual(c, b))) candidates.push(b);
+	}
+	if (candidates.length === 0) return null;
+	if (!pathYM) return candidates[0];
+	const aligned = candidates.find((c) => ymdAgreesWithYM(c, pathYM));
+	return aligned ?? candidates[0];
+}
+
+function pickUnixTimestamp(fileName: string, originalName: string): YMD | null {
+	return (
+		parseUnixTimestampInName(fileName) ??
+		(originalName && originalName !== fileName
+			? parseUnixTimestampInName(originalName)
+			: null)
+	);
+}
+
+export function suggestDateFromPath(input: Input): DateGuess | null {
 	const fileName = (input.fileName ?? '').trim();
+	const originalName = (input.originalName ?? '').trim();
 	const path = (input.path ?? '').trim();
 
-	const fnMatch = fileName.match(BASENAME_YMD);
-	if (fnMatch) {
-		const iso = tryDate(Number(fnMatch[1]), Number(fnMatch[2]), Number(fnMatch[3]));
-		if (iso) return iso;
+	const pathYMD = path ? parsePathYMD(path) : null;
+	const pathYM = path && !pathYMD ? parsePathYM(path) : null;
+
+	// 1. Filename Y-M-D corroborated by the path.
+	const fnYMD = pickFilenameYMD(fileName, originalName, pathYM);
+	if (fnYMD) {
+		if (pathYMD && ymdEqual(fnYMD, pathYMD)) {
+			return { iso: isoOf(fnYMD), confidence: 'high', source: 'filename-agrees-path' };
+		}
+		if (pathYM && ymdAgreesWithYM(fnYMD, pathYM)) {
+			return { iso: isoOf(fnYMD), confidence: 'high', source: 'filename-agrees-path' };
+		}
+		// 2. Filename Y-M-D with no path signal at all.
+		if (!pathYMD && !pathYM) {
+			return { iso: isoOf(fnYMD), confidence: 'high', source: 'filename-only' };
+		}
+		// Filename present but disagrees with path → fall through.
 	}
 
-	if (path) {
-		const ymd = path.match(PATH_YMD);
-		if (ymd) {
-			const iso = tryDate(Number(ymd[1]), Number(ymd[2]), Number(ymd[3]));
-			if (iso) return iso;
+	// 3. Unix epoch in filename, optionally corroborated.
+	const epoch = pickUnixTimestamp(fileName, originalName);
+	if (epoch) {
+		if (!pathYM && !pathYMD) {
+			return { iso: isoOf(epoch), confidence: 'high', source: 'unix-timestamp' };
 		}
-		const ym = path.match(PATH_YM);
-		if (ym) {
-			const iso = tryDate(Number(ym[1]), Number(ym[2]), 1);
-			if (iso) return iso;
+		if (pathYM && ymdAgreesWithYM(epoch, pathYM)) {
+			return { iso: isoOf(epoch), confidence: 'high', source: 'unix-timestamp' };
+		}
+		if (pathYMD && ymdEqual(epoch, pathYMD)) {
+			return { iso: isoOf(epoch), confidence: 'high', source: 'unix-timestamp' };
+		}
+		// disagreement → fall through to path
+	}
+
+	// 4. Path Y-M-D standalone.
+	if (pathYMD) {
+		return { iso: isoOf(pathYMD), confidence: 'high', source: 'path-ymd' };
+	}
+
+	// 5. Path Y-M with synthesised day = 01.
+	if (pathYM) {
+		const ymd = tryYMD(pathYM.y, pathYM.m, 1);
+		if (ymd) {
+			return { iso: isoOf(ymd), confidence: 'medium', source: 'path-ym-default-day' };
 		}
 	}