Added Rates Service: Base, Coinbase, Composite

packages/stack/tests/rates/rates-composite.spec.ts

@@ -0,0 +1,128 @@
+import { describe, it, expect } from 'vitest';
+import { Satoshis } from '@xocash/primitives';
+
+import {
+  RatesComposite,
+  BaseRates,
+  RatesCoinbase,
+} from '~/src/index.js';
+
+/**
+ * A simple stub that implements BaseRates and returns fixed values.
+ */
+class StubRate extends BaseRates {
+  constructor(private factor: number) {
+    super();
+  }
+
+  public async start(): Promise<void> {}
+  public async stop(): Promise<void> {}
+
+  /** Return a fixed rate factor */
+  public async getRate(): Promise<number> {
+    return this.factor;
+  }
+
+  /** toBCH returns Satoshis.fromBCH(amount * factor) */
+  public async toBCH(amount: number): Promise<Satoshis> {
+    return Satoshis.fromBCH(amount / this.factor);
+  }
+
+  /** fromBCH returns (BCH amount) * factor */
+  public async fromBCH(amount: Satoshis): Promise<number> {
+    return amount.toBCH() * this.factor;
+  }
+}
+
+// --- Unit tests with in-memory stub rates ---
+describe('RatesComposite (unit) with two stub rates', () => {
+  // Use 99 and 101 so average will be exactly 100
+  const stub1 = new StubRate(99);
+  const stub2 = new StubRate(101);
+  const composite = new RatesComposite([stub1, stub2]);
+
+  it('getRate should average the two rates to 100', async () => {
+    // Act: composite over stub rates
+    const avg = await composite.getRate('ANY');
+    // Assert: (99 + 101) / 2 = 100
+    expect(avg).toBeCloseTo(100, 3);
+  });
+
+  it('toBCH should average returned BCH to 100 BCH', async () => {
+    // amount=1, stub1 gives 99 BCH, stub2 gives 101 BCH -> avg = 100 BCH
+    const sats = await composite.toBCH(1, 'ANY');
+
+    // Expect 1 USD = 1/100 BCH
+    expect(sats.toBCH()).toBeCloseTo(0.01, 3);
+  });
+
+  it('fromBCH should average returned foreign value to 100', async () => {
+    // 1 BCH => stub1 returns 99, stub2 returns 101 -> avg = 100
+    const value = await composite.fromBCH(Satoshis.fromBCH(1), 'ANY');
+    expect(value).toBeCloseTo(100, 3);
+  });
+});
+
+describe('RatesComposite (unit) with two very different stub rates', () => {
+  const stub1 = new StubRate(100);
+  const stub2 = new StubRate(600);
+  const composite = new RatesComposite([stub1, stub2]);
+  
+  it('toBCH should average returned BCH to 100 BCH', async () => {
+    // amount=1, stub1 gives 100 per BCH, stub2 gives 600 per BCH -> avg = 350 per BCH
+    const sats = await composite.toBCH(1, 'ANY');
+
+    // Expect 1 USD = 1/350 BCH
+    expect(sats.toBCH()).toBeCloseTo(0.00285, 4);
+  });
+
+  it('fromBCH should average returned foreign value to 100', async () => {
+    // 1 BCH => stub1 returns 100, stub2 returns 600 -> avg = 350
+    const value = await composite.fromBCH(Satoshis.fromBCH(1), 'ANY');
+    expect(value).toBeCloseTo(350, 3);
+  });
+
+  it('composite toBCH/fromBCH roundtrip USD', async () => {
+    const sats = await composite.toBCH(1, 'USD');
+    expect(sats.toBigInt()).toBeGreaterThan(BigInt(0));
+
+    const back = await composite.fromBCH(sats, 'USD');
+    expect(back).toBeGreaterThan(0);
+    expect(back).toBeCloseTo(1.00, 3);
+  });
+
+
+});
+
+// --- Integration tests combining CoinbaseRates and GpOraclesRates ---
+describe('AvgCompositeRates (integration) combining Coinbase & OracleRates', () => {
+  it('integration: composite BCH->USD from Coinbase+Oracle should yield > 0', async () => {
+    const cb = RatesCoinbase.from();
+    const mockRate = new StubRate(99);
+
+    const composite = new RatesComposite([cb, mockRate]);
+    await composite.start();
+    
+    const rate = await composite.getRate('USD');
+
+    await composite.stop();
+    expect(rate).toBeGreaterThan(0);
+  }, 20000);
+
+  it('integration: composite toBCH/fromBCH roundtrip USD', async () => {
+    const cb = RatesCoinbase.from();
+    const mockRate = new StubRate(100);
+
+    const composite = new RatesComposite([cb, mockRate]);
+    await composite.start();
+    
+    const sats = await composite.toBCH(1, 'USD');
+    expect(sats.toBigInt()).toBeGreaterThan(BigInt(0));
+    
+    const back = await composite.fromBCH(sats, 'USD');
+    expect(back).toBeGreaterThan(0);
+    expect(back).toBeCloseTo(1.00, 3);
+    
+    await composite.stop();
+  }, 20000);
+});