phase-6: typescript introduction

server/screener/assets/Bond.ts

@@ -0,0 +1,47 @@
+import { CREDIT_RATING_SCALE } from '../../config/ScoringConfig.js';
+import { Asset } from './Asset.js';
+
+interface BondData {
+  ticker?: string;
+  currentPrice?: number;
+  creditRating?: string;
+  yieldToMaturity?: string | number;
+  duration?: string | number;
+  [key: string]: unknown;
+}
+
+export interface BondMetrics {
+  ytm: number;
+  duration: number;
+  creditRating: string;
+  creditRatingNumeric: number;
+}
+
+export class Bond extends Asset {
+  metrics: BondMetrics;
+
+  constructor(data: BondData) {
+    super(data);
+
+    const creditRating = data.creditRating || 'BBB';
+    const creditRatingNumeric = CREDIT_RATING_SCALE[creditRating] ?? 7;
+
+    this.metrics = {
+      ytm: parseFloat(String(data.yieldToMaturity)) || 0,
+      duration: parseFloat(String(data.duration)) || 0,
+      creditRating,
+      creditRatingNumeric,
+    };
+  }
+
+  getDisplayMetrics(): Record<string, string> {
+    return {
+      Ticker: this.ticker,
+      Type: 'BOND',
+      Price: this.formatCurrency(this.currentPrice),
+      'YTM%': `${this.metrics.ytm.toFixed(2)}%`,
+      Duration: this.metrics.duration.toFixed(1),
+      Rating: `${this.metrics.creditRating} (${this.metrics.creditRatingNumeric})`,
+    };
+  }
+}