feat(budget): flip grid to income-first + add Résultat rows

Align BudgetTable on the income-statement standard shipped for the
compare/trend reports: sections now read Income -> Expense -> Transfer
(useBudget's TYPE_ORDER and BudgetTable's typeOrder both flipped), and
the previously unlabeled grand-total row is replaced by two interleaved
result rows (Result before transfers / Net result), computed by a new
pure, tested module (budgetTableResults.ts) mirroring compareResults.ts's
shape. Roll-up covers the previous-year-actual, budgeted-annual, and
budgeted-monthly columns alike.

All categories remain displayed (the grid stays a full edit surface) --
no collapse, no empty-row toggle, matching this issue's frozen decisions.

Resolves #278

CHANGELOG.fr.md

@@ -19,6 +19,7 @@
 ### Modifié
 
 - Rapports → Tendances : le rapport **s'ouvre désormais sur la vue « Par catégorie » en tableau** par défaut, au lieu du graphique mensuel global. Le tableau par catégorie comporte une section revenus, donc une catégorie de revenu (ex. votre paie) apparaît d'emblée — sans changer de vue au préalable. La vue que vous choisissez vous-même reste mémorisée (#262).
+- Budget : la grille budget se lit désormais comme une analyse de résultat — les catégories sont regroupées **Revenus → Dépenses → Transferts** (auparavant dépenses en premier), et l'ancienne ligne « Total » brute est remplacée par deux lignes de résultat : **Résultat avant transferts** (revenus − dépenses) et **Résultat net** (après transferts), calculées sur les colonnes année précédente, annuelle et mensuelles. Toutes les catégories restent affichées sur la grille — elle demeure une surface d'édition, sans ligne masquée ni repliable (#278).
 
 ## [0.12.0] - 2026-07-05
 

CHANGELOG.md

@@ -19,6 +19,7 @@
 ### Changed
 
 - Reports → Trends: the report now **opens on the "By category" table view** by default, instead of the global monthly chart. The by-category table has an income section, so a revenue category (e.g. your pay) shows up straight away — no need to switch views first. Whatever view you pick yourself is still remembered (#262).
+- Budget: the budget grid now reads as an income statement — categories are grouped **Income → Expenses → Transfers** (previously expenses first), and the old plain "Total" row is replaced by two result lines: **Result before transfers** (income − expenses) and **Net result** (after transfers), computed across the previous-year, annual, and monthly columns alike. Every category still shows on the grid — it stays an editable surface, with no rows hidden or collapsed (#278).
 
 ## [0.12.0] - 2026-07-05
 

src/components/budget/BudgetTable.tsx

@@ -3,6 +3,7 @@ import { useTranslation } from "react-i18next";
 import { AlertTriangle, ArrowUpDown } from "lucide-react";
 import type { BudgetYearRow } from "../../shared/types";
 import { reorderRows } from "../../utils/reorderRows";
+import { computeBudgetResults, type BudgetTotals } from "./budgetTableResults";
 
 const fmt = new Intl.NumberFormat("en-CA", {
   style: "currency",
@@ -127,7 +128,9 @@ export default function BudgetTable({ rows, onUpdatePlanned, onSplitEvenly }: Bu
     grouped[key].push(row);
   }
 
-  const typeOrder = ["expense", "income", "transfer"] as const;
+  // Income-statement reading order: revenue first, then expenses, then
+  // transfers (Issue #278) — matches the compare/trend reports' ordering.
+  const typeOrder = ["income", "expense", "transfer"] as const;
   const typeLabelKeys: Record<string, string> = {
     expense: "budget.expenses",
     income: "budget.income",
@@ -139,19 +142,12 @@ export default function BudgetTable({ rows, onUpdatePlanned, onSplitEvenly }: Bu
     transfer: "budget.totalTransfers",
   };
 
-  // Column totals with sign convention (only count leaf rows to avoid double-counting parents)
-  const monthTotals: number[] = Array(12).fill(0);
-  let annualTotal = 0;
-  let prevYearTotal = 0;
-  for (const row of rows) {
-    if (row.is_parent) continue; // skip parent subtotals to avoid double-counting
-    const sign = signFor(row.category_type);
-    for (let m = 0; m < 12; m++) {
-      monthTotals[m] += row.months[m] * sign;
-    }
-    annualTotal += row.annual * sign;
-    prevYearTotal += row.previousYearTotal; // actuals are already signed in the DB
-  }
+  // Income-statement roll-up (Issue #278): Résultat avant transferts / net,
+  // computed on the budgeted + previous-year-actual leaves. Mathematically
+  // equivalent to the old plain grand-total (income − expense + transfer over
+  // every leaf), now surfaced as the two labeled result rows below instead of
+  // a single unlabeled "Total".
+  const results = computeBudgetResults(rows);
 
   const totalCols = 15; // category + prev year + annual + 12 months
 
@@ -295,39 +291,10 @@ export default function BudgetTable({ rows, onUpdatePlanned, onSplitEvenly }: Bu
     );
   };
 
-  return (
-    <div className="bg-[var(--card)] rounded-xl border border-[var(--border)] overflow-hidden">
-      <div className="flex justify-end px-3 py-2 border-b border-[var(--border)]">
-        <button
-          onClick={toggleSubtotals}
-          className="inline-flex items-center gap-1.5 px-2.5 py-1 rounded-lg text-xs font-medium text-[var(--muted-foreground)] hover:bg-[var(--muted)] transition-colors"
-        >
-          <ArrowUpDown size={13} />
-          {subtotalsOnTop ? t("reports.subtotalsOnTop") : t("reports.subtotalsOnBottom")}
-        </button>
-      </div>
-      <div className="overflow-x-auto overflow-y-auto" style={{ maxHeight: "calc(100vh - 220px)" }}>
-      <table className="w-full text-sm whitespace-nowrap">
-        <thead className="sticky top-0 z-20">
-          <tr className="border-b border-[var(--border)] bg-[var(--card)]">
-            <th className="text-left py-2.5 px-3 font-medium text-[var(--muted-foreground)] sticky left-0 bg-[var(--card)] z-30 min-w-[140px]">
-              {t("budget.category")}
-            </th>
-            <th className="text-right py-2.5 px-2 font-medium text-[var(--muted-foreground)] min-w-[90px]">
-              {t("budget.previousYear")}
-            </th>
-            <th className="text-right py-2.5 px-2 font-medium text-[var(--muted-foreground)] min-w-[90px]">
-              {t("budget.annual")}
-            </th>
-            {MONTH_KEYS.map((key) => (
-              <th key={key} className="text-right py-2.5 px-2 font-medium text-[var(--muted-foreground)] min-w-[70px]">
-                {t(key)}
-              </th>
-            ))}
-          </tr>
-        </thead>
-        <tbody>
-          {typeOrder.map((type) => {
+  // One type's section: header, its (reorderable) rows, and a leaf-summed
+  // subtotal row. Extracted so it can be called for income/expense, then
+  // again for transfer once the Résultat rows are interleaved between them.
+  const renderTypeSection = (type: (typeof typeOrder)[number]) => {
     const group = grouped[type];
     if (!group || group.length === 0) return null;
     const sign = signFor(type);
@@ -367,18 +334,76 @@ export default function BudgetTable({ rows, onUpdatePlanned, onSplitEvenly }: Bu
         </tr>
       </Fragment>
     );
-          })}
-          {/* Totals row */}
-          <tr className="bg-[var(--muted)] font-bold border-t-2 border-[var(--border)]">
-            <td className="py-3 px-3 sticky left-0 bg-[var(--muted)] z-10 text-sm">{t("common.total")}</td>
-            <td className="py-3 px-2 text-right text-sm text-[var(--muted-foreground)]">{formatSigned(prevYearTotal)}</td>
-            <td className="py-3 px-2 text-right text-sm">{formatSigned(annualTotal)}</td>
-            {monthTotals.map((total, mIdx) => (
-              <td key={mIdx} className="py-3 px-2 text-right text-sm">
-                {formatSigned(total)}
+  };
+
+  // A Résultat row (avant-transferts subtotal, or the net bottom line).
+  // `strong` mirrors the previous grand-total row's weight (bold, border-t-2);
+  // the softer variant mirrors the per-type section-subtotal row above.
+  const renderResultRow = (labelKey: string, tot: BudgetTotals, strong: boolean) => {
+    const rowClass = strong
+      ? "bg-[var(--muted)] font-bold border-t-2 border-[var(--border)]"
+      : "bg-[var(--muted)]/40 border-b border-[var(--border)]";
+    const stickyBg = strong ? "bg-[var(--muted)]" : "bg-[var(--muted)]/40";
+    const cellWeight = strong ? "" : "font-semibold";
+    const pad = strong ? "py-3" : "py-2.5";
+    return (
+      <tr key={labelKey} className={rowClass}>
+        <td className={`${pad} px-3 sticky left-0 z-10 text-sm ${stickyBg}`}>{t(labelKey)}</td>
+        <td className={`${pad} px-2 text-right text-sm ${cellWeight} text-[var(--muted-foreground)]`}>
+          {formatSigned(tot.previousYearTotal)}
+        </td>
+        <td className={`${pad} px-2 text-right text-sm ${cellWeight}`}>{formatSigned(tot.annual)}</td>
+        {tot.months.map((val, mIdx) => (
+          <td key={mIdx} className={`${pad} px-2 text-right text-sm ${cellWeight}`}>
+            {formatSigned(val)}
           </td>
         ))}
       </tr>
+    );
+  };
+
+  return (
+    <div className="bg-[var(--card)] rounded-xl border border-[var(--border)] overflow-hidden">
+      <div className="flex justify-end px-3 py-2 border-b border-[var(--border)]">
+        <button
+          onClick={toggleSubtotals}
+          className="inline-flex items-center gap-1.5 px-2.5 py-1 rounded-lg text-xs font-medium text-[var(--muted-foreground)] hover:bg-[var(--muted)] transition-colors"
+        >
+          <ArrowUpDown size={13} />
+          {subtotalsOnTop ? t("reports.subtotalsOnTop") : t("reports.subtotalsOnBottom")}
+        </button>
+      </div>
+      <div className="overflow-x-auto overflow-y-auto" style={{ maxHeight: "calc(100vh - 220px)" }}>
+      <table className="w-full text-sm whitespace-nowrap">
+        <thead className="sticky top-0 z-20">
+          <tr className="border-b border-[var(--border)] bg-[var(--card)]">
+            <th className="text-left py-2.5 px-3 font-medium text-[var(--muted-foreground)] sticky left-0 bg-[var(--card)] z-30 min-w-[140px]">
+              {t("budget.category")}
+            </th>
+            <th className="text-right py-2.5 px-2 font-medium text-[var(--muted-foreground)] min-w-[90px]">
+              {t("budget.previousYear")}
+            </th>
+            <th className="text-right py-2.5 px-2 font-medium text-[var(--muted-foreground)] min-w-[90px]">
+              {t("budget.annual")}
+            </th>
+            {MONTH_KEYS.map((key) => (
+              <th key={key} className="text-right py-2.5 px-2 font-medium text-[var(--muted-foreground)] min-w-[70px]">
+                {t(key)}
+              </th>
+            ))}
+          </tr>
+        </thead>
+        <tbody>
+          {renderTypeSection("income")}
+          {renderTypeSection("expense")}
+          {/* Operating result (revenues − expenses), interleaved before the
+              transfers section only when transfers exist — otherwise it
+              equals the net result below and would just be noise. */}
+          {results.hasTransfers &&
+            renderResultRow("reports.compare.resultBeforeTransfers", results.resultBefore, false)}
+          {renderTypeSection("transfer")}
+          {/* Bottom line: result after netting transfers. */}
+          {renderResultRow("reports.compare.resultNet", results.resultNet, true)}
         </tbody>
       </table>
       </div>

src/components/budget/budgetTableResults.test.ts

@@ -0,0 +1,94 @@
+import { describe, it, expect } from "vitest";
+import type { BudgetYearRow } from "../../shared/types";
+import { computeBudgetResults, sumLeavesForType, signForBudgetType } from "./budgetTableResults";
+
+// Minimal leaf factory. `months` arrives as the positive-magnitude budgeted
+// figure BudgetTable itself flips by type via `signFor` — same convention
+// `sumLeavesForType` re-implements. `annual` always equals `sum(months)`
+// (useBudget derives it that way; see useBudget.ts's `buildMonths`).
+function leaf(
+  type: BudgetYearRow["category_type"],
+  months: number[],
+  previousYearTotal = 0,
+  overrides: Partial<BudgetYearRow> = {},
+): BudgetYearRow {
+  return {
+    category_id: 1,
+    category_name: type,
+    category_color: "#000",
+    category_type: type,
+    parent_id: null,
+    is_parent: false,
+    depth: 0,
+    months,
+    annual: months.reduce((s, v) => s + v, 0),
+    previousYearTotal,
+    ...overrides,
+  };
+}
+
+const FLAT12 = (v: number) => Array(12).fill(v) as number[];
+
+describe("computeBudgetResults — income-statement roll-up (Issue #278)", () => {
+  it("resultBefore = budgeted income − expense; resultNet adds transfers", () => {
+    const r = computeBudgetResults([
+      leaf("income", FLAT12(400)), // annual 4800
+      leaf("expense", FLAT12(300)), // annual 3600, stored positive, flipped to -300/mo
+      leaf("transfer", FLAT12(0)),
+    ]);
+    expect(r.resultBefore.months[0]).toBe(100); // 400 − 300
+    expect(r.resultBefore.annual).toBe(1200); // 4800 − 3600
+    expect(r.resultNet.annual).toBe(1200); // balanced (0) transfer → unchanged
+    expect(r.hasTransfers).toBe(true);
+  });
+
+  it("an unbalanced (one-leg) transfer moves resultNet away from resultBefore", () => {
+    const r = computeBudgetResults([
+      leaf("income", FLAT12(1000)),
+      leaf("expense", FLAT12(700)),
+      leaf("transfer", FLAT12(50)), // uncategorized single leg, signed pass-through
+    ]);
+    expect(r.resultBefore.annual).toBe(3600); // (1000 − 700) × 12
+    expect(r.resultNet.annual).toBe(4200); // resultBefore + transfer(50×12)
+  });
+
+  it("a deficit yields a negative net result and no transfer line when absent", () => {
+    const r = computeBudgetResults([leaf("income", FLAT12(200)), leaf("expense", FLAT12(250))]);
+    expect(r.resultNet.months[0]).toBe(-50);
+    expect(r.hasTransfers).toBe(false);
+  });
+
+  it("ignores subtotal (is_parent) rows so a group is not double-counted", () => {
+    const parent = leaf("expense", FLAT12(999), 0, { is_parent: true });
+    const r = computeBudgetResults([parent, leaf("expense", FLAT12(100))]);
+    expect(r.expense.annual).toBe(-1200); // only the leaf's 100 × 12 (flipped), not 999
+  });
+
+  it("carries the previous-year actual through unsigned (already signed in the DB)", () => {
+    // Actual totals arrive pre-signed: expense negative, income positive.
+    const r = computeBudgetResults([
+      leaf("income", FLAT12(100), 1150),
+      leaf("expense", FLAT12(60), -650),
+    ]);
+    expect(r.resultBefore.previousYearTotal).toBe(500); // 1150 + (−650), no re-sign
+  });
+
+  it("sumLeavesForType filters by type and excludes parents", () => {
+    const t = sumLeavesForType(
+      [
+        leaf("expense", FLAT12(50)),
+        leaf("expense", FLAT12(999), 0, { is_parent: true }),
+        leaf("income", FLAT12(10)),
+      ],
+      "expense",
+    );
+    expect(t.annual).toBe(-600); // 50 × 12, flipped negative
+    expect(t.months[0]).toBe(-50);
+  });
+
+  it("signForBudgetType flips expense only", () => {
+    expect(signForBudgetType("expense")).toBe(-1);
+    expect(signForBudgetType("income")).toBe(1);
+    expect(signForBudgetType("transfer")).toBe(1);
+  });
+});

src/components/budget/budgetTableResults.ts

@@ -0,0 +1,94 @@
+import type { BudgetYearRow } from "../../shared/types";
+
+export type BudgetSectionType = "income" | "expense" | "transfer";
+
+/**
+ * Sign multiplier applied to budgeted (months/annual) magnitudes. Budgeted
+ * amounts are entered/stored as positive magnitudes regardless of type and
+ * flipped for display by category type — mirrors `BudgetTable`'s `signFor`.
+ */
+export function signForBudgetType(type: BudgetSectionType): 1 | -1 {
+  return type === "expense" ? -1 : 1;
+}
+
+/**
+ * Aggregate of the budget grid's 3 comparable column groups, already signed:
+ * 12 monthly (budgeted) totals, the annual (budgeted) total, and the
+ * previous-year (actual) total.
+ */
+export interface BudgetTotals {
+  /** index 0-11 = Jan-Dec, signed budgeted total */
+  months: number[];
+  /** signed budgeted annual total */
+  annual: number;
+  /** signed actual total from the previous year (already signed in the DB) */
+  previousYearTotal: number;
+}
+
+function zeroTotals(): BudgetTotals {
+  return { months: Array(12).fill(0) as number[], annual: 0, previousYearTotal: 0 };
+}
+
+/**
+ * Sum every non-subtotal (leaf) row of a single type into one `BudgetTotals`.
+ *
+ * The type's sign is applied to the budgeted figures (`months`/`annual`),
+ * matching how `BudgetTable` displays them. `previousYearTotal` is NOT
+ * re-signed: it comes from `getActualTotalsForYear` (a plain signed
+ * `SUM(amount)` over the transactions table), already negative for expenses
+ * and ~0-net for balanced transfers — the same convention `compareResults.ts`
+ * relies on for its own previous-period figures.
+ */
+export function sumLeavesForType(rows: BudgetYearRow[], type: BudgetSectionType): BudgetTotals {
+  const sign = signForBudgetType(type);
+  const totals = zeroTotals();
+  for (const row of rows) {
+    if (row.is_parent || row.category_type !== type) continue;
+    for (let m = 0; m < 12; m++) totals.months[m] += row.months[m] * sign;
+    totals.annual += row.annual * sign;
+    totals.previousYearTotal += row.previousYearTotal;
+  }
+  return totals;
+}
+
+/** Component-wise sum of two BudgetTotals (both already signed). */
+function combine(a: BudgetTotals, b: BudgetTotals): BudgetTotals {
+  return {
+    months: a.months.map((v, i) => v + b.months[i]),
+    annual: a.annual + b.annual,
+    previousYearTotal: a.previousYearTotal + b.previousYearTotal,
+  };
+}
+
+export interface BudgetResults {
+  income: BudgetTotals;
+  expense: BudgetTotals;
+  transfer: BudgetTotals;
+  /** Budgeted/actual revenues − expenses: the operating result, before transfers. */
+  resultBefore: BudgetTotals;
+  /** resultBefore + transfers: the bottom-line total. */
+  resultNet: BudgetTotals;
+  hasTransfers: boolean;
+}
+
+/**
+ * Income-statement roll-up for the budget grid (Issue #278), mirroring
+ * `compareResults.ts`'s shape (see that module's doc comment for the sign
+ * convention this relies on).
+ *
+ * Operates on the flat `BudgetYearRow[]` the grid already renders (produced
+ * by `useBudget`) — LEAVES only (`is_parent === false`), so parent subtotal
+ * rows are never double-counted. All three column groups (previous-year
+ * actual, budgeted annual, budgeted monthly) are folded into the same result
+ * rows so "Résultat avant transferts" / "Résultat net" read consistently
+ * across every column of the grid.
+ */
+export function computeBudgetResults(rows: BudgetYearRow[]): BudgetResults {
+  const income = sumLeavesForType(rows, "income");
+  const expense = sumLeavesForType(rows, "expense");
+  const transfer = sumLeavesForType(rows, "transfer");
+  const resultBefore = combine(income, expense);
+  const resultNet = combine(resultBefore, transfer);
+  const hasTransfers = rows.some((r) => !r.is_parent && r.category_type === "transfer");
+  return { income, expense, transfer, resultBefore, resultNet, hasTransfers };
+}

src/hooks/useBudget.ts

@@ -68,7 +68,10 @@ function reducer(state: BudgetState, action: BudgetAction): BudgetState {
   }
 }
 
-const TYPE_ORDER: Record<string, number> = { expense: 0, income: 1, transfer: 2 };
+// Income-statement reading order: revenue first, then expenses, then
+// transfers (Issue #278) — matches the compare/trend reports' ordering
+// (`COMPARE_TYPE_ORDER` / `OVER_TIME_TYPE_ORDER`, income-first since #253).
+const TYPE_ORDER: Record<string, number> = { income: 0, expense: 1, transfer: 2 };
 
 export function useBudget() {
   const { accountIds } = useReportsPeriod();