Fix fraud dashboard lint issues

backend/fraud/controller/fraudAnalyticsController.ts

@@ -0,0 +1,85 @@
+/**
+ * Fraud Analytics REST API (framework-agnostic handler functions)
+ *
+ * Endpoints:
+ *   GET  /fraud/analytics/summary         – overall fraud summary
+ *   GET  /fraud/analytics/trend           – time-series trend
+ *   GET  /fraud/analytics/top-risk        – top risk merchants
+ *   GET  /fraud/analytics/signals         – fraud signal breakdown
+ *   GET  /fraud/analytics/report/:id      – per-merchant fraud report
+ *   GET  /fraud/analytics/recommendations – prevention recommendations
+ */
+
+import { fraudAnalyticsService } from '../../services/analytics/fraudAnalyticsService';
+
+// ── Response helpers ──────────────────────────────────────────────────────────
+
+function ok(data: unknown) {
+  return { success: true, data };
+}
+
+function err(message: string, status = 400) {
+  return { success: false, error: { message }, status };
+}
+
+// ── Handlers ──────────────────────────────────────────────────────────────────
+
+/**
+ * GET /fraud/analytics/summary
+ * Query params: merchantId (optional)
+ */
+export function getFraudSummary(params: { merchantId?: string }) {
+  const summary = fraudAnalyticsService.getFraudSummary(params.merchantId);
+  return ok(summary);
+}
+
+/**
+ * GET /fraud/analytics/trend
+ * Query params: days (optional, default 30, max 90)
+ */
+export function getFraudTrend(params: { days?: string }) {
+  const days = params.days !== undefined ? parseInt(params.days, 10) : 30;
+  if (Number.isNaN(days) || days < 1 || days > 90) {
+    return err('days must be a number between 1 and 90');
+  }
+  return ok(fraudAnalyticsService.getFraudTrend(days));
+}
+
+/**
+ * GET /fraud/analytics/top-risk
+ * Query params: limit (optional, default 10)
+ */
+export function getTopRiskMerchants(params: { limit?: string }) {
+  const limit = params.limit !== undefined ? parseInt(params.limit, 10) : 10;
+  if (Number.isNaN(limit) || limit < 1 || limit > 100) {
+    return err('limit must be a number between 1 and 100');
+  }
+  return ok(fraudAnalyticsService.getTopRiskMerchants(limit));
+}
+
+/**
+ * GET /fraud/analytics/signals
+ */
+export function getSignalBreakdown() {
+  return ok(fraudAnalyticsService.getSignalBreakdown());
+}
+
+/**
+ * GET /fraud/analytics/report/:merchantId
+ */
+export function getFraudReport(merchantId: string) {
+  if (!merchantId || merchantId.trim() === '') {
+    return err('merchantId is required', 400);
+  }
+  const report = fraudAnalyticsService.generateFraudReport(merchantId);
+  return ok(report);
+}
+
+/**
+ * GET /fraud/analytics/recommendations
+ * Query params: merchantId (optional)
+ */
+export function getPreventionRecommendations(params: { merchantId?: string }) {
+  const recs = fraudAnalyticsService.getPreventionRecommendations(params.merchantId);
+  return ok(recs);
+}

backend/fraud/controller/fraudInvestigationController.ts

@@ -0,0 +1,196 @@
+/**
+ * Fraud Investigation REST API (framework-agnostic handler functions)
+ *
+ * Endpoints:
+ *   GET    /fraud/investigations              – list cases with optional filters
+ *   GET    /fraud/investigations/:caseId      – get single case
+ *   POST   /fraud/investigations              – open a case manually
+ *   PATCH  /fraud/investigations/:caseId      – update case (assign, resolve, escalate, dismiss)
+ *   GET    /fraud/investigations/:caseId/notes – list notes for case
+ *   POST   /fraud/investigations/:caseId/notes – add a note to case
+ *   GET    /fraud/investigations/stats         – aggregate statistics
+ *
+ *   POST   /fraud/report                       – generate full fraud report for a merchant
+ */
+
+import { fraudInvestigationService, InvestigationFilter } from '../domain/FraudInvestigationService';
+import { FraudReviewOutcome, FraudReviewStatus } from '../../../src/types/fraud';
+
+// ── Response helpers ──────────────────────────────────────────────────────────
+
+function ok(data: unknown) {
+  return { success: true, data };
+}
+
+function err(message: string, status = 400) {
+  return { success: false, error: { message }, status };
+}
+
+// ── Handlers ──────────────────────────────────────────────────────────────────
+
+/** GET /fraud/investigations */
+export function listCases(params: {
+  status?: string;
+  merchantId?: string;
+  subscriberId?: string;
+  minRiskScore?: string;
+  limit?: string;
+  offset?: string;
+}) {
+  const filter: InvestigationFilter = {};
+
+  if (params.status) {
+    const validStatuses: FraudReviewStatus[] = ['pending', 'reviewed', 'dismissed', 'escalated'];
+    if (!validStatuses.includes(params.status as FraudReviewStatus)) {
+      return err(`Invalid status. Must be one of: ${validStatuses.join(', ')}`);
+    }
+    filter.status = params.status as FraudReviewStatus;
+  }
+
+  if (params.merchantId) filter.merchantId = params.merchantId;
+  if (params.subscriberId) filter.subscriberId = params.subscriberId;
+
+  if (params.minRiskScore) {
+    const score = parseInt(params.minRiskScore, 10);
+    if (Number.isNaN(score) || score < 0 || score > 100) {
+      return err('minRiskScore must be a number between 0 and 100');
+    }
+    filter.minRiskScore = score;
+  }
+
+  if (params.limit) {
+    const limit = parseInt(params.limit, 10);
+    if (Number.isNaN(limit) || limit < 1 || limit > 200) {
+      return err('limit must be a number between 1 and 200');
+    }
+    filter.limit = limit;
+  }
+
+  if (params.offset) {
+    const offset = parseInt(params.offset, 10);
+    if (Number.isNaN(offset) || offset < 0) {
+      return err('offset must be a non-negative number');
+    }
+    filter.offset = offset;
+  }
+
+  return ok(fraudInvestigationService.getCases(filter));
+}
+
+/** GET /fraud/investigations/:caseId */
+export function getCase(caseId: string) {
+  const fraudCase = fraudInvestigationService.getCase(caseId);
+  if (!fraudCase) return err(`Case ${caseId} not found`, 404);
+  return ok(fraudCase);
+}
+
+/** POST /fraud/investigations */
+export function createCase(body: {
+  subscriptionId?: string;
+  subscriberId?: string;
+  merchantId?: string;
+  merchantName?: string;
+  subscriptionName?: string;
+  riskScore?: number;
+  reason?: string;
+}) {
+  if (!body.subscriptionId) return err('subscriptionId is required');
+  if (!body.subscriberId) return err('subscriberId is required');
+  if (!body.merchantId) return err('merchantId is required');
+  if (!body.merchantName) return err('merchantName is required');
+  if (!body.subscriptionName) return err('subscriptionName is required');
+  if (body.riskScore === undefined || body.riskScore === null) {
+    return err('riskScore is required');
+  }
+  if (body.riskScore < 0 || body.riskScore > 100) {
+    return err('riskScore must be between 0 and 100');
+  }
+  if (!body.reason) return err('reason is required');
+
+  const fraudCase = fraudInvestigationService.createCase({
+    subscriptionId: body.subscriptionId,
+    subscriberId: body.subscriberId,
+    merchantId: body.merchantId,
+    merchantName: body.merchantName,
+    subscriptionName: body.subscriptionName,
+    riskScore: body.riskScore,
+    reason: body.reason,
+  });
+
+  return ok(fraudCase);
+}
+
+/** PATCH /fraud/investigations/:caseId */
+export function updateCase(
+  caseId: string,
+  body: {
+    action?: 'assign' | 'resolve' | 'escalate' | 'dismiss' | 'start_review';
+    reviewer?: string;
+    outcome?: string;
+    notes?: string;
+  },
+) {
+  if (!body.action) return err('action is required');
+
+  switch (body.action) {
+    case 'assign': {
+      if (!body.reviewer) return err('reviewer is required for assign action');
+      const result = fraudInvestigationService.assignReviewer(caseId, body.reviewer);
+      return result.success ? ok(result.case) : err(result.error ?? 'Unknown error', 404);
+    }
+
+    case 'start_review': {
+      if (!body.reviewer) return err('reviewer is required for start_review action');
+      const result = fraudInvestigationService.startReview(caseId, body.reviewer);
+      return result.success ? ok(result.case) : err(result.error ?? 'Unknown error', 404);
+    }
+
+    case 'resolve': {
+      const validOutcomes: FraudReviewOutcome[] = ['true_positive', 'false_positive', 'needs_follow_up'];
+      if (!body.outcome || !validOutcomes.includes(body.outcome as FraudReviewOutcome)) {
+        return err(`outcome must be one of: ${validOutcomes.join(', ')}`);
+      }
+      const result = fraudInvestigationService.resolveCase(
+        caseId,
+        body.outcome as FraudReviewOutcome,
+        body.notes,
+      );
+      return result.success ? ok(result.case) : err(result.error ?? 'Unknown error', 404);
+    }
+
+    case 'escalate': {
+      const result = fraudInvestigationService.escalateCase(caseId, body.notes);
+      return result.success ? ok(result.case) : err(result.error ?? 'Unknown error', 404);
+    }
+
+    case 'dismiss': {
+      const result = fraudInvestigationService.dismissCase(caseId, body.notes);
+      return result.success ? ok(result.case) : err(result.error ?? 'Unknown error', 404);
+    }
+
+    default:
+      return err(`Unknown action: ${body.action as string}`);
+  }
+}
+
+/** GET /fraud/investigations/:caseId/notes */
+export function getCaseNotes(caseId: string) {
+  const fraudCase = fraudInvestigationService.getCase(caseId);
+  if (!fraudCase) return err(`Case ${caseId} not found`, 404);
+  return ok(fraudInvestigationService.getNotes(caseId));
+}
+
+/** POST /fraud/investigations/:caseId/notes */
+export function addCaseNote(caseId: string, body: { author?: string; content?: string }) {
+  if (!body.author) return err('author is required');
+  if (!body.content || body.content.trim() === '') return err('content is required');
+
+  const note = fraudInvestigationService.addNote(caseId, body.author, body.content);
+  if (!note) return err(`Case ${caseId} not found`, 404);
+  return ok(note);
+}
+
+/** GET /fraud/investigations/stats */
+export function getInvestigationStats() {
+  return ok(fraudInvestigationService.getStats());
+}