add apply-interest script

apply-interest.js

@@ -0,0 +1,60 @@
+const api = require('@actual-app/api');
+const { closeBudget, ensurePayee, getAccountBalance, getAccountNote, getLastTransactionDate, openBudget } = require('./utils');
+require("dotenv").config();
+
+(async () => {
+  await openBudget();
+
+  const payeeId = await ensurePayee(process.env.IMPORTER_INTEREST_PAYEE_NAME || 'Loan Interest');
+
+  const accounts = await api.getAccounts();
+  for (const account of accounts) {
+    if (account.closed) {
+      continue;
+    }
+
+    const note = await getAccountNote(account);
+
+    if (note) {
+      if (note.indexOf('interestRate:') > -1 && note.indexOf('interestDay:') > -1) {
+        const interestRate = parseFloat(note.split('interestRate:')[1].split(' ')[0]);
+        const interestDay = parseInt(note.split('interestDay:')[1].split(' ')[0]);
+
+        const interestTransactionDate = new Date();
+        if (interestTransactionDate.getDate() < interestDay) {
+          interestTransactionDate.setMonth(interestTransactionDate.getMonth() - 1);
+        }
+        interestTransactionDate.setDate(interestDay);
+        interestTransactionDate.setHours(5, 0, 0, 0);
+
+        const cutoff = new Date(interestTransactionDate);
+        cutoff.setMonth(cutoff.getMonth() - 1);
+        cutoff.setDate(cutoff.getDate() + 1);
+
+        const lastDate = await getLastTransactionDate(account, cutoff);
+        if (!lastDate) continue;
+        const daysPassed = Math.floor((interestTransactionDate - new Date(lastDate)) / 86400000);
+
+        const balance = await getAccountBalance(account, interestTransactionDate);
+        const compoundedInterest = Math.round(balance * (Math.pow(1 + interestRate / 12, 1) - 1));
+
+        console.log(`== ${account.name} ==`);
+        console.log(` -> Balance:  ${balance}`);
+        console.log(`      as of ${lastDate}`);
+        console.log(` -> # days:   ${daysPassed}`);
+        console.log(` -> Interest: ${compoundedInterest}`)
+
+        if (compoundedInterest) {
+          await api.importTransactions(account.id, [{
+            date: interestTransactionDate,
+            payee: payeeId,
+            amount: compoundedInterest,
+            notes: `Interest for 1 month at ${100*interestRate}%`,
+          }]);
+        }
+      }
+    }
+  }
+
+  await closeBudget();
+})();