feat(shared): give a payment a tab to settle

A payment has only ever recorded from, to, amount and date. That is why
the per-trip owed figure did not exist — getTripAnalytics said so where
the number should have been: "split_payments carries no trip attribution,
so a payment cannot be assigned to a trip. Settlement is a property of the
whole relationship." Every trip therefore read 100% unsettled, including
trips paid in full.

It is also why the Shared page silently drops payments under a tag filter.
With one global pool there was nothing honest to subtract, so it showed
gross splits under the same label. A tag is a view; a scope is a ledger.

The scope is a trip, not a new settlement_contexts table. trips already
has owner_id, dates and archived, and transaction_overrides.trip_id
already decides membership. A second grouping beside it would be two
unsynchronised scopes over the same rows, with no invariant saying which
governs. NULL means the ongoing household tab, which never closes.

settled answers a different question and the two must not be collapsed:
trip_id is which tab, settled is whether the obligation is still live.
Critically, a live obligation is NOT settled by flipping the flag — it is
settled by recording the payment, and the balance nets to zero on its own.
Doing both would subtract the settlement twice. So settled is written only
by the historical import, for repayments made on a platform we no longer
run, and there is deliberately no "mark settled" action.

Both owed figures now exclude settled splits and the trip figure nets its
own payments. Spend analytics (myShare/mySplitOf) deliberately still count
settled rows: my half of a 2025 grocery shop is my spend whether or not the
other half was ever repaid, and filtering them would re-inflate exactly the
figures importing settled history exists to correct.

Also drops /api/participants/[id]/balance. It had no consumers, no owner
scoping, no debit/credit signs and no EXCLUDE_RECONCILED_SOURCE — a fourth
balance implementation that disagreed with the others and would have
imported three bugs if anything had aligned to it.

getTripAnalytics had no test at all. It has five now, including the one
that matters: a household payment must not make a trip look paid. Verified
by mutation — neutering the settled filter fails three, and dropping the
trip filter on payments fails that one.
This commit is contained in:
2026-07-27 23:12:05 +10:00
parent a4ab543a6c
commit 689fadc8b9
7 changed files with 250 additions and 57 deletions
+50 -21
View File
@@ -1,5 +1,5 @@
import { queryRaw } from "./db";
import { EXCLUDE_RECONCILED_SOURCE, NATIVE_CURRENCY, AMOUNT_UNCONVERTED } from "./analytics-sql";
import { EXCLUDE_RECONCILED_SOURCE, NATIVE_CURRENCY, AMOUNT_UNCONVERTED, ACTIVE_OBLIGATION } from "./analytics-sql";
export interface RoutePointRow {
label: string;
@@ -448,6 +448,13 @@ export async function getParticipantBalances(ownerId: number, tagIds?: number[])
// Payments settle the total relationship between two people, not a specific tag.
// Only subtract payments when viewing the unfiltered total; with a tag filter
// active, show the raw split amount for that tag context only.
//
// That asymmetry is a symptom, not a design: a tag is a view and has no
// payments, so a tag-filtered balance had nothing honest to subtract. A trip
// does have payments (`split_payments.trip_id`, migration 0022), which is why
// the per-trip figure in getTripAnalytics can be netted and this one cannot.
// The fix for the tag case is to stop showing a balance there, not to invent
// one — see docs/shared-expenses-design.md.
const paymentsJoin = tagIds?.length ? "" : `
LEFT JOIN (
SELECT
@@ -484,6 +491,7 @@ export async function getParticipantBalances(ownerId: number, tagIds?: number[])
LEFT JOIN statements s ON s.id = t.statement_id
WHERE COALESCE(t.owner_id, s.owner_id) = $1 AND ts.participant_id != $1
AND ${EXCLUDE_RECONCILED_SOURCE}
AND ${ACTIVE_OBLIGATION}
${tagFilter}
UNION ALL
@@ -498,6 +506,7 @@ export async function getParticipantBalances(ownerId: number, tagIds?: number[])
LEFT JOIN statements s ON s.id = t.statement_id
WHERE ts.participant_id = $1 AND COALESCE(t.owner_id, s.owner_id) != $1
AND ${EXCLUDE_RECONCILED_SOURCE}
AND ${ACTIVE_OBLIGATION}
${tagFilter}
) splits ON splits.pid = p.id
${paymentsJoin}
@@ -929,27 +938,47 @@ export async function getTripAnalytics(tripId: number, ownerId: number): Promise
ORDER BY 4 DESC
`, [tripId]),
// No settled/unsettled breakdown here. It was computed from
// transaction_splits.settled, which only /api/splits/settle writes and
// nothing in the UI calls — so it is false on all 673 splits and every trip
// reported 100% unsettled, including trips paid in full. A real per-trip
// figure is not computable either: split_payments carries no trip
// attribution, so a payment cannot be assigned to a trip. Settlement is a
// property of the whole relationship until settlement contexts exist
// (see docs/shared-expenses-design.md).
// Owed per participant for THIS trip, net of payments made against it.
//
// This was gross splits, with a comment explaining why it could not be
// anything better: `split_payments` carried no trip attribution, so a
// payment could not be assigned to a trip and every trip reported 100%
// unsettled including trips paid in full. `split_payments.trip_id`
// (migration 0022) closes that, so the figure is now real.
//
// Two exclusions, both load-bearing:
// - ACTIVE_OBLIGATION drops settled splits, so a closed trip reads zero
// rather than its original gross.
// - EXCLUDE_RECONCILED_SOURCE drops the manual row a statement line has
// superseded. The trip queries never applied it, so a reconciled trip
// expense was counted twice here.
queryRaw<{ participant_id: number; name: string; owed: number }>(`
SELECT
p.id AS participant_id,
p.name,
SUM(ts.share_percent / 100.0 * COALESCE(tx.amount_aud, tx.amount))::float AS owed
FROM transaction_overrides o
JOIN transactions tx ON tx.id = o.transaction_id
JOIN transaction_splits ts ON ts.transaction_id = tx.id
JOIN participants p ON p.id = ts.participant_id
WHERE o.trip_id = $1
AND tx.transaction_type IN ('debit','fee','interest')
AND COALESCE(o.category_override, tx.category, 'other') NOT IN ('transfers', 'investment')
GROUP BY p.id
WITH owed AS (
SELECT ts.participant_id AS pid,
SUM(ts.share_percent / 100.0 * COALESCE(tx.amount_aud, tx.amount)) AS gross
FROM transaction_overrides o
JOIN transactions tx ON tx.id = o.transaction_id
LEFT JOIN statements s ON s.id = tx.statement_id
JOIN transaction_splits ts ON ts.transaction_id = tx.id
WHERE o.trip_id = $1
AND tx.transaction_type IN ('debit','fee','interest')
AND COALESCE(o.category_override, tx.category, 'other') NOT IN ('transfers', 'investment')
AND ${ACTIVE_OBLIGATION}
AND NOT (tx.statement_id IS NULL AND tx.reconciled_with_id IS NOT NULL)
GROUP BY ts.participant_id
),
paid AS (
SELECT sp.from_participant_id AS pid, SUM(sp.amount) AS amt
FROM split_payments sp
WHERE sp.trip_id = $1
GROUP BY sp.from_participant_id
)
SELECT p.id AS participant_id, p.name,
(COALESCE(owed.gross, 0) - COALESCE(paid.amt, 0))::float AS owed
FROM participants p
LEFT JOIN owed ON owed.pid = p.id
LEFT JOIN paid ON paid.pid = p.id
WHERE owed.pid IS NOT NULL OR paid.pid IS NOT NULL
ORDER BY 3 DESC
`, [tripId]),
]);