added CurrencyProvider and associated spec

app/src/providers/currency/currency.spec.ts

@@ -0,0 +1,78 @@
+/* tslint:disable:no-unused-variable */
+import { TestBed, ComponentFixture, inject } from '@angular/core/testing';
+import { HttpModule } from '@angular/http';
+import { CurrencyProvider } from './currency';
+
+describe('CurrencyProvider', () => {
+  let currency;
+
+  beforeEach(() => {
+    TestBed.configureTestingModule({
+      imports: [
+        HttpModule
+      ],
+      providers: [
+        CurrencyProvider
+      ]
+    });
+  });
+
+  beforeEach(inject([CurrencyProvider], _cp => {
+    currency = _cp;
+  }));
+
+  it('initialises', () => {
+    expect(currency).not.toBeNull();
+    expect(currency.defaultCurrency).toBe('BTC');
+    expect(currency.currencySymbol).toBe('BTC');
+    expect(currency.factor).toBe(1);
+  });
+
+  it('sets currency by updating the symbol and changing the multiplication factor', () => {
+    currency.setCurrency('USD');
+    expect(currency.currencySymbol).toBe('USD');
+    expect(currency.factor).toEqual(1);
+
+    currency.setCurrency('BTC');
+    expect(currency.currencySymbol).toBe('BTC');
+    expect(currency.factor).toEqual(1);
+
+    currency.setCurrency('mBTC');
+    expect(currency.currencySymbol).toBe('mBTC');
+    expect(currency.factor).toEqual(1000);
+
+    currency.setCurrency('bits');
+    expect(currency.currencySymbol).toBe('bits');
+    expect(currency.factor).toEqual(1000000);
+  });
+
+  it('rounds float using specified number of decimal places', () => {
+    let aFloat = 4.32943;
+
+    expect(currency.roundFloat(aFloat, 2)).toBe(4.33);
+    expect(currency.roundFloat(aFloat, 3)).toBe(4.329);
+    expect(currency.roundFloat(aFloat, 4)).toBe(4.3294);
+    expect(currency.roundFloat(aFloat, 5)).toBe(4.32943);
+
+    aFloat = 1234567890.09876543;
+
+    expect(currency.roundFloat(aFloat, 2)).toBe(1234567890.10);
+    expect(currency.roundFloat(aFloat, 3)).toBe(1234567890.099);
+    expect(currency.roundFloat(aFloat, 4)).toBe(1234567890.0988);
+    expect(currency.roundFloat(aFloat, 5)).toBe(1234567890.09877);
+    expect(currency.roundFloat(aFloat, 6)).toBe(1234567890.098765);
+    expect(currency.roundFloat(aFloat, 7)).toBe(1234567890.0987654);
+    expect(currency.roundFloat(aFloat, 8)).toBe(1234567890.09876543);
+  });
+
+  it('gets proper conversion after changing currency', () => {
+    let aFloat = 12345.09876543;
+    expect(currency.getConversion(aFloat)).toBe('12345.09876543 BTC');
+
+    currency.setCurrency('mBTC');
+    expect(currency.getConversion(aFloat)).toBe('12345098.76543 mBTC');
+
+    currency.setCurrency('bits');
+    expect(currency.getConversion(aFloat)).toBe('12345098765.43 bits');
+  });
+});

app/src/providers/currency/currency.ts

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+import { Injectable } from '@angular/core';
+import { Http } from '@angular/http';
+import 'rxjs/add/operator/map';
+
+/*
+  Generated class for the CurrencyProvider provider.
+
+  See https://angular.io/docs/ts/latest/guide/dependency-injection.html
+  for more info on providers and Angular DI.
+*/
+@Injectable()
+export class CurrencyProvider {
+
+  private defaultCurrency: string;
+  private currencySymbol: string;
+  private factor: number = 1;
+
+  constructor(public http: Http) {
+    this.defaultCurrency = 'BTC';
+    this.currencySymbol = this.defaultCurrency;
+  }
+
+  private roundFloat(aFloat: number, decimalPlaces: number): number {
+    return Math.round(aFloat * Math.pow(10, decimalPlaces)) / Math.pow(10, decimalPlaces);
+  }
+
+  public getConversion(value: number): string {
+    if (value === 0.00000000) return '0 ' + this.currencySymbol; // fix value to show
+
+    let response: number;
+
+    if (this.currencySymbol === 'USD') {
+      response = this.roundFloat((value * this.factor), 2);
+    } else if (this.currencySymbol === 'mBTC') {
+      this.factor = 1000;
+      response = this.roundFloat((value * this.factor), 5);
+    } else if (this.currencySymbol === 'bits') {
+      this.factor = 1000000;
+      response = this.roundFloat((value * this.factor), 2);
+    } else { // assumes currencySymbol is BTC
+      this.factor = 1;
+      response = this.roundFloat((value * this.factor), 8);
+    }
+
+    return response + ' ' + this.currencySymbol;
+  }
+
+  public setCurrency(currency: string): void {
+    this.currencySymbol = currency;
+    localStorage.setItem('insight-currency', currency);
+
+    if (currency === 'USD') {
+      // TODO Replace this with call
+      /*
+      Currency.get({}, function(res) {
+        $rootScope.currency.factor = $rootScope.currency.bitstamp = res.data.bitstamp;
+      });
+       */
+    } else if (currency === 'mBTC') {
+      this.factor = 1000;
+    } else if (currency === 'bits') {
+      this.factor = 1000000;
+    } else {
+      this.factor = 1;
+    }
+  }
+
+}