refactor: centralize domain values and enforce numeric lint

src/modules/investments/instruments/application/instrument-market.ts

@@ -1,16 +1,21 @@
+import { MILLISECONDS_PER_SECOND } from '../../../../common/time';
 import { ServiceUnavailableException } from '@nestjs/common';
 import type {
   TbankCandle,
   TbankTimestamp,
 } from '../../../../integrations/tbank/tbank.api';
+
+const MOSCOW_OFFSET_MS = 10_800_000;
 export function timestamp(value?: TbankTimestamp): string | null {
   const seconds = Number(value?.seconds);
   return Number.isFinite(seconds) && seconds > 0
-    ? new Date(seconds * 1000).toISOString()
+    ? new Date(seconds * MILLISECONDS_PER_SECOND).toISOString()
     : null;
 }
 export function moscowDay(iso: string): string {
-  return new Date(Date.parse(iso) + 3 * 3_600_000).toISOString().slice(0, 10);
+  return new Date(Date.parse(iso) + MOSCOW_OFFSET_MS)
+    .toISOString()
+    .slice(0, 10);
 }
 export function previousClose(
   candles: TbankCandle[],

src/modules/investments/instruments/application/instrument-position.ts

@@ -13,6 +13,9 @@ import {
 } from '../../portfolio/portfolio.api';
 import { StockPositionDto } from '../stocks/presentation/stock.dto';
 
+const PRICE_DECIMAL_PLACES = 9;
+const RETURN_PERCENT_DECIMAL_PLACES = 6;
+
 export function instrumentPosition(
   portfolio: PortfolioDto,
   uid: string,
@@ -41,7 +44,11 @@ export function instrumentPosition(
         ? {
             currency: totalCost.currency,
             value: formatDecimal(
-              divide(decimalFromString(totalCost.value), quantity, 9),
+              divide(
+                decimalFromString(totalCost.value),
+                quantity,
+                PRICE_DECIMAL_PLACES,
+              ),
             ),
           }
         : null,
@@ -103,7 +110,7 @@ function percent(
     divide(
       multiply(decimalFromString(result.value), decimalFromString('100')),
       decimalFromString(base.value),
-      6,
+      RETURN_PERCENT_DECIMAL_PLACES,
     ),
   );
 }