Add multicurrency support

src/balance-utils.ts

@@ -168,9 +168,12 @@ export type DailyAccountBalanceChangeMap = Map<string, Map<string, number>>;
  * If an account has no balance change on a date, that key will not be included
  * in the inner map. If a date has no transactions, that key will not be
  * included in the outer map.
+ * 
+ * Only transactions matching the passed currencySymbol will be included.
  */
 export const makeDailyAccountBalanceChangeMap = (
   transactions: EnhancedTransaction[],
+  currencySymbol: string,
 ): DailyAccountBalanceChangeMap => {
   // This map contains a mapping from every day (YYYY-MM-DD) to account names to
   // a list of all balance changes.
@@ -191,6 +194,10 @@ export const makeDailyAccountBalanceChangeMap = (
         return; // Must be a comment line
       }
 
+      if (line.currency != currencySymbol) {
+          return;
+      }
+
       getWithDefault(
         accounts,
         line.dealiasedAccount,

src/parser.ts

@@ -415,8 +415,8 @@ export const fillMissingAmount = (
 ): Result<null, TxError> => {
   const lines = tx.value.expenselines;
   let missingLine: Expenseline | undefined;
-  let missingIndex = -1;
-  let currency = '';
+
+  let totals: Map<string, number> = new Map<string, number>();
 
   for (let i = 0; i < lines.length; i++) {
     const line = lines[i];
@@ -435,28 +435,38 @@ export const fillMissingAmount = (
         });
       }
       missingLine = line;
-      missingIndex = i;
     } else if (line.currency) {
-      currency = line.currency;
+      // Calculate running total for each currency
+      if (!totals.has(line.currency)) {
+          totals.set(line.currency, 0);
+      }
+
+      totals.set(line.currency!, totals.get(line.currency)! + line.amount!);
     }
   }
 
   if (!missingLine) {
     return ok(null);
   }
 
-  if (currency) {
-    missingLine.currency = currency;
-  }
-  missingLine.amount =
-    -1 *
-    lines.reduce((prev, line, i): number => {
-      if (i === missingIndex || !('account' in line)) {
-        return prev;
-      }
+  let account = missingLine.account;
+
+  // Remove initial missing line and repopulate with lines for each currency
+  tx.value.expenselines.remove(missingLine);
 
-      return line.amount !== undefined ? prev + line.amount : prev;
-    }, 0);
+  Array.from(totals.entries()).forEach(([currency, total]) => {
+    if (total === 0) {
+      return;
+    }
+    tx.value.expenselines.push(
+      {
+        account,
+        amount: -1 * total,
+        currency,
+        comment: '',
+      },
+    );
+  });
 
   return ok(null);
 };

src/transaction-utils.ts

@@ -55,6 +55,44 @@ export const getTotal = (
   return currency + total.toFixed(2);
 };
 
+/**
+ * getCurrencyTotals returns the total values of the transaction. It returns a
+ * string separated by newlines, with a line for each currency.
+ */
+export const getCurrencyTotals = (
+    tx: EnhancedTransaction
+): string => {
+    let totals: Map<string, number> = new Map<string, number>();
+
+    console.log(tx.value.expenselines);
+
+    let currentSignPositive = null;
+
+    for (let i = 0; i < tx.value.expenselines.length; i++) {
+        const line = tx.value.expenselines[i];
+
+        if ('currency' in line && line.currency) {
+            // Track the sign of the first value and skip lines that differ.
+            // We continue instead of breaking in case the transactions flip-flop
+            // between positive and negative, as unlikely as that is.
+            if (currentSignPositive === null) {
+                currentSignPositive = line.amount >= 0;
+            } else if (currentSignPositive === (line.amount < 0)) {
+                continue;
+            }
+
+            if (!totals.has(line.currency)) {
+                totals.set(line.currency, 0);
+            }
+
+            totals.set(line.currency, totals.get(line.currency)! + line.amount);
+        }
+    }
+
+    return Array.from(totals).map(([key, value]) => key + value.toFixed(2)).join("\n");
+};
+
+
 export const getTotalAsNum = (tx: EnhancedTransaction): number => {
   // The total of an EnhancedTransaction is -1 * the last line that is not a comment
   for (let i = tx.value.expenselines.length - 1; i >= 0; i--) {

src/ui/LedgerDashboard.tsx

@@ -97,6 +97,7 @@ const DesktopDashboard: React.FC<{
 
     const changeMap = makeDailyAccountBalanceChangeMap(
       props.txCache.transactions,
+      props.settings.currencySymbol,
     );
     const balanceMap = makeDailyBalanceMap(
       props.txCache.accounts,

src/ui/TransactionList.tsx

@@ -10,6 +10,7 @@ import {
   filterByStartDate,
   filterTransactions,
   getTotal,
+  getCurrencyTotals,
 } from '../transaction-utils';
 import { Moment } from 'moment';
 import React from 'react';
@@ -178,7 +179,7 @@ const buildTableRows = (
       return {
         date: tx.value.date,
         payee: tx.value.payee,
-        total: getTotal(tx, currencySymbol),
+        total: getCurrencyTotals(tx),
         from: nonCommentLines[1].account,
         to: nonCommentLines[0].account,
         actions: makeClone(tx),
@@ -188,7 +189,7 @@ const buildTableRows = (
     return {
       date: tx.value.date,
       payee: tx.value.payee,
-      total: getTotal(tx, currencySymbol),
+      total: getCurrencyTotals(tx),
       from: nonCommentLines[nonCommentLines.length - 1].account,
       to: <i>Multiple</i>,
       actions: makeClone(tx),
@@ -200,7 +201,7 @@ const buildTableRows = (
     const aDate = window.moment(a.date);
     const bDate = window.moment(b.date);
     if (aDate.isSame(bDate)) {
-      return 0;
+      return -1;
     }
     return aDate.isBefore(bDate) ? 1 : -1;
   });
@@ -342,7 +343,9 @@ const TransactionTable: React.FC<{
             return (
               <tr {...row.getRowProps()}>
                 {row.cells.map((cell) => (
-                  <td {...cell.getCellProps()}>{cell.render('Cell')}</td>
+                    // Whitespace styling to support Total column newlines
+                    // There's definitely a better way to style this.
+                    <td style={{ whiteSpace: "pre" }} {...cell.getCellProps()}>{cell.render('Cell')}</td>
                 ))}
               </tr>
             );

tests/balance-utils.test.ts

@@ -197,7 +197,7 @@ describe('Balance maps', () => {
   describe('makeDailyAccountBalanceChangeMap()', () => {
     test('simple test', () => {
       const input = [tx4, tx5, tx6];
-      const result = makeDailyAccountBalanceChangeMap(input);
+      const result = makeDailyAccountBalanceChangeMap(input, "");
       expect(result).toEqual(expectedDailyAccountBalanceChangeMap);
     });
   });