Budget vs Actuals: show full per-period budget, no proration

The Budget column overlap-weighted partial months, so a YTD range
ending mid-month showed a fractional budget. Now include each budget
period's full amount whenever the selected window touches it, for both
the main and comparison windows — exactly as entered on the budget.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/pages/accounting/AccountingReportsPage.tsx

@@ -2000,16 +2000,16 @@ function BudgetVsActuals({ companyId, from, to, currency, companyName, rangeLabe
 
   const selectedBudget = useMemo(() => (budgets as any[]).find((b) => b.id === budgetId), [budgets, budgetId]);
 
-  // Budget pro-rated to the selected actuals window (B2): sum each budget period
+  // Budget for the selected actuals window: include each budget period's FULL
-  // weighted by how much of it overlaps [actFrom, actTo]. period_index maps to
+  // amount, exactly as entered, for any period the window touches — no proration.
-  // months (monthly), quarters (quarterly), or the whole year (annual).
+  // period_index maps to months (monthly), quarters (quarterly), or the whole
+  // year (annual). E.g. Jan 1 – Jun 16 = full Jan…Jun monthly budgets.
   const budgetByAcct = useMemo(() => {
     const m: Record<string, number> = {};
     const pt = String(selectedBudget?.period_type ?? "annual");
     const fy = Number(selectedBudget?.fiscal_year) || new Date(actFrom || actTo || Date.now()).getFullYear();
     const fromT = actFrom ? new Date(actFrom).getTime() : -Infinity;
     const toT = actTo ? new Date(actTo).getTime() : Infinity;
-    const DAY = 86400000;
     const span = (idx: number): [number, number] => {
       if (pt === "monthly") return [new Date(fy, idx, 1).getTime(), new Date(fy, idx + 1, 0).getTime()];
       if (pt === "quarterly") return [new Date(fy, idx * 3, 1).getTime(), new Date(fy, idx * 3 + 3, 0).getTime()];
@@ -2017,11 +2017,8 @@ function BudgetVsActuals({ companyId, from, to, currency, companyName, rangeLabe
     };
     for (const e of (entries as any[])) {
       const [s, en] = span(Number(e.period_index) || 0);
-      const overlap = Math.max(0, Math.min(en, toT) - Math.max(s, fromT));
+      if (s > toT || en < fromT) continue; // period not touched by the window
-      const full = en - s;
+      m[e.account_id] = (m[e.account_id] ?? 0) + Number(e.amount);
-      const weight = full > 0 ? Math.min(1, (overlap + DAY) / (full + DAY)) : 1;
-      if (weight <= 0) continue;
-      m[e.account_id] = (m[e.account_id] ?? 0) + Number(e.amount) * weight;
     }
     return m;
   }, [entries, selectedBudget, actFrom, actTo]);
@@ -2029,7 +2026,8 @@ function BudgetVsActuals({ companyId, from, to, currency, companyName, rangeLabe
   const actualByAcct = useMemo(() => computeBvaActuals(actualsData), [actualsData]);
   const cmpActualByAcct = useMemo(() => computeBvaActuals(cmpActualsData), [cmpActualsData]);
 
-  // Comparison-window budget (pro-rated like budgetByAcct, over [cmpFrom, cmpTo]).
+  // Comparison-window budget (full per-period amounts like budgetByAcct, over
+  // [cmpFrom, cmpTo]). No proration.
   const cmpBudgetByAcct = useMemo(() => {
     const m: Record<string, number> = {};
     if (!cmpOn || !cmpFrom || !cmpTo) return m;
@@ -2037,7 +2035,6 @@ function BudgetVsActuals({ companyId, from, to, currency, companyName, rangeLabe
     const fy = Number(selectedBudget?.fiscal_year) || new Date(cmpFrom || cmpTo || Date.now()).getFullYear();
     const fromT = new Date(cmpFrom).getTime();
     const toT = new Date(cmpTo).getTime();
-    const DAY = 86400000;
     const span = (idx: number): [number, number] => {
       if (pt === "monthly") return [new Date(fy, idx, 1).getTime(), new Date(fy, idx + 1, 0).getTime()];
       if (pt === "quarterly") return [new Date(fy, idx * 3, 1).getTime(), new Date(fy, idx * 3 + 3, 0).getTime()];
@@ -2045,11 +2042,8 @@ function BudgetVsActuals({ companyId, from, to, currency, companyName, rangeLabe
     };
     for (const e of (entries as any[])) {
       const [s, en] = span(Number(e.period_index) || 0);
-      const overlap = Math.max(0, Math.min(en, toT) - Math.max(s, fromT));
+      if (s > toT || en < fromT) continue; // period not touched by the window
-      const full = en - s;
+      m[e.account_id] = (m[e.account_id] ?? 0) + Number(e.amount);
-      const weight = full > 0 ? Math.min(1, (overlap + DAY) / (full + DAY)) : 1;
-      if (weight <= 0) continue;
-      m[e.account_id] = (m[e.account_id] ?? 0) + Number(e.amount) * weight;
     }
     return m;
   }, [entries, selectedBudget, cmpOn, cmpFrom, cmpTo]);
@@ -2194,7 +2188,7 @@ function BudgetVsActuals({ companyId, from, to, currency, companyName, rangeLabe
             <Button onClick={exportPDF}><FileDown className="mr-1 h-4 w-4" /> PDF</Button>
           </div>
           <div className="w-full text-xs text-muted-foreground">
-            Budget pro-rated to the selected period ({String((selectedBudget as any)?.period_type ?? "annual")} budget).
+            Budget shows the full {String((selectedBudget as any)?.period_type ?? "annual")} amounts for every period the selected range touches — exactly as entered, no proration.
           </div>
         </CardContent>
       </Card>