Add report generator

src/reportGen.ts

@@ -0,0 +1,55 @@
+interface ReportSummary {
+    totalReports: number;
+    firstTimestamp: Date;
+    lastTimestamp: Date;
+    reportsPerUnit: Record<string, number>;
+}
+
+interface Report {
+    unitNumber: string;
+    reported: string;
+    comments: string;
+    utcTimestamp: string;
+    faults: string[];
+}
+
+export async function organiseReports(): Promise<ReportSummary> {
+  try {
+    const res = await fetch('https://rep.fjla.uk/fetch');
+    if (!res.ok) throw new Error(`Fetch failed: ${res.statusText}`);
+
+    const reports: Report[] = await res.json();
+
+    if (reports.length === 0) {
+        return {
+            totalReports: 0,
+            firstTimestamp: new Date(0), // Epoch
+            lastTimestamp: new Date(0),
+            reportsPerUnit: {},
+        };
+    }
+
+    // Sort by string utcTimestamp (lexical sort works fine for ISO strings)
+    reports.sort((a, b) => a.utcTimestamp.localeCompare(b.utcTimestamp));
+
+    const firstTimestamp = reports[0].utcTimestamp;
+    const lastTimestamp = reports[reports.length - 1].utcTimestamp;
+    const totalReports = reports.length;
+
+    const reportsPerUnit: Record<string, number> = {};
+    for (const report of reports) {
+      const unit = report.unitNumber;
+      reportsPerUnit[unit] = (reportsPerUnit[unit] || 0) + 1;
+    }
+
+    return {
+        totalReports,
+        firstTimestamp: new Date(firstTimestamp),
+        lastTimestamp: new Date(lastTimestamp),
+        reportsPerUnit,
+    };
+  } catch (err) {
+    console.error('Error organising reports:', err);
+    throw err;
+  }
+}