items-by-period (#2)

Reviewed-on: #2
Co-authored-by: Vishesh 'ironeagle' Bangotra <aetoskia@gmail.com>
Co-committed-by: Vishesh 'ironeagle' Bangotra <aetoskia@gmail.com>

src/components/LatestItems/LatestItems.adapter.ts

@@ -0,0 +1,66 @@
+import { ReportData, Transaction, GroupKey } from "../../features/report";
+import {
+  mergeBucketPeriods,
+  periodIdToKey,
+  formatCurrency,
+  filterBuckets,
+} from "../report.helpers";
+import { LatestItem } from "./LatestItems.models";
+
+// ─── Transaction extraction ─────────────────────────────────
+
+function extractTransactions(
+  reportData: ReportData,
+  selectedPeriodId: string | null,
+  selectedGroupKey: GroupKey | null,
+  mode: "expense" | "income"
+): Transaction[] {
+  const buckets = filterBuckets(reportData.buckets, selectedGroupKey);
+  if (selectedPeriodId) {
+    const key = periodIdToKey(selectedPeriodId);
+    const periods = mergeBucketPeriods(buckets, key);
+    const selected = periods.find((p) => p.id === selectedPeriodId);
+
+    if (!selected) return [];
+
+    return mode === "expense"
+      ? (selected.expenses.transactions || [])
+      : (selected.incomes.transactions || []);
+  }
+
+  const periods = mergeBucketPeriods(buckets, "full");
+
+  if (!periods.length) return [];
+
+  const full = periods[0];
+
+  return mode === "expense"
+    ? (full.expenses.transactions || [])
+    : (full.incomes.transactions || []);
+}
+
+// ─── Main adapter ────────────────────────────────────────────
+
+export function buildLatestItems(
+  reportData: ReportData,
+  selectedPeriodId: string | null,
+  selectedGroupKey: GroupKey | null,
+  mode: "expense" | "income"
+): LatestItem[] {
+  const txns = extractTransactions(reportData, selectedPeriodId, selectedGroupKey, mode);
+
+  return txns
+    .filter((t) => (mode === "expense" ? t.amount < 0 : t.amount >= 0))
+    .sort(
+      (a, b) =>
+        new Date(b.occurred_at).getTime() -
+        new Date(a.occurred_at).getTime()
+    )
+    .map((t, index) => ({
+      id: index + 1,
+      title: t.payee.name,
+      subtitle: t.tags.map((tag) => tag.name).join(", "),
+      amount: formatCurrency(t.amount),
+      timeAgo: new Date(t.occurred_at).toLocaleDateString("en-IN"),
+    }));
+}