A node.js based web app for income tax calculation.
Originally created by Sonic with help of ChatGPT (OpenAI) on Dec 2023, Chongqing, China.
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implement the calculation with python code
main.pyandmain_v2.py -
as the chatGPT helping implementing a node.js app with frontend and backend.
- this app can receive six parameters
- calculate the sum and average of the six parameters in the nodejs backend
- display asynchronously the calculation result in the frontend
index.htmlpage
-
Continue asking the chatGPT for further functions adding:
- implement the functions for this app with the description in the python code given
- it works fine and small-and-non-functional human-fixing need.
- done.
-
Todo and to earn:
- Optimize the app for good-looking and easy-use.
- How to design/assign the bonus_included_income for minimum
totalIncomeTaxresult? - Imagine you have a billion bonus, how to split it by a fine designed Five-year disbursement plan? How to design that plan?
- Add a wechat pay for a smart-plan designing.
mkdir nodejs-income-calculator
cd nodejs-income-calculator
npm init -y
npm install express body-parser
touch index.js
mkdir public
cd public
touch index.html
cd ..// index.js
const express = require('express');
const path = require('path');
const bodyParser = require('body-parser');
const app = express();
const port = 3000;
// Serve static files from the public dir
app.use(express.static(path.join(__dirname, 'public')));
app.use(bodyParser.urlencoded({ extended: true }));
app.use(bodyParser.json());
// Display the form, The '/form' route serves the HTML file with the form.
app.get('/form', (req, res) => {
res.sendFile(path.join(__dirname, 'public', 'index.html'));
});
// Handle form submissions and calculate on the backend
app.post('/submit', (req, res) => {
// Extract values from the form and parse as integers
const startTaxPoint = parseInt(req.body.start_tax_point_month, 10);
const preTaxIncome = parseInt(req.body.pre_tax_income, 10);
const annualBonus = parseInt(req.body.annual_bonus, 10);
const bonusIncludedIncome = parseInt(req.body.bonus_included_income, 10);
const insuranceFund = parseInt(req.body.insurance_fund, 10);
const deductions = parseInt(req.body.deductions, 10);
// Calculate sum and average
const sum = startTaxPoint + preTaxIncome + annualBonus + bonusIncludedIncome + insuranceFund + deductions;
const average = sum / 6;
// Send the result back to the frontend
res.json({ sum, average });
});
app.listen(port, () => {
console.log(`Server is running at http://localhost:${port}`);
});<!-- public/index.html -->
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Income Tax Calculator</title>
</head>
<body>
<h1>Income Calculator</h1>
<form id="incomeForm">
<label for="start_tax_point_month">月收入起征点:</label>
<input type="number" id="start_tax_point_month" name="start_tax_point_month" required><br>
<label for="pre_tax_income">税前工资收入:</label>
<input type="number" id="pre_tax_income" name="pre_tax_income" required><br>
<label for="annual_bonus">年终奖总额:</label>
<input type="number" id="annual_bonus" name="annual_bonus" required><br>
<label for="bonus_included_income">年终奖计入工资部分:</label>
<input type="number" id="bonus_included_income" name="bonus_included_income" required><br>
<label for="insurance_fund">五险两金（个人年缴纳部分）:</label>
<input type="number" id="insurance_fund" name="insurance_fund" required><br>
<label for="deductions">专项扣除（子女、老人、教育、房租、房贷等）:</label>
<input type="number" id="deductions" name="deductions" required><br>
<button type="button" onclick="calculate()">Calculate</button>
</form>
<h2>Result:</h2>
<p id="result"></p>
<script>
async function calculate() {
// Extract values from the form
const startTaxPoint = parseFloat(document.getElementById('start_tax_point_month').value);
const preTaxIncome = parseFloat(document.getElementById('pre_tax_income').value);
const annualBonus = parseFloat(document.getElementById('annual_bonus').value);
const bonusIncludedIncome = parseFloat(document.getElementById('bonus_included_income').value);
const insuranceFund = parseFloat(document.getElementById('insurance_fund').value);
const deductions = parseFloat(document.getElementById('deductions').value);
// Create an object with the form data
const formData = {
start_tax_point_month: startTaxPoint,
pre_tax_income: preTaxIncome,
annual_bonus: annualBonus,
bonus_included_income: bonusIncludedIncome,
insurance_fund: insuranceFund,
deductions: deductions,
};
try {
// Send an asynchronous POST request to the server
const response = await fetch('/submit', {
method: 'POST',
headers: {
'Content-Type': 'application/json',
},
body: JSON.stringify(formData),
});
// Parse the JSON response
const result = await response.json();
// Display the result on the page
document.getElementById('result').innerHTML = `Sum: ${result.sum}, Average: ${result.average.toFixed(2)}`;
} catch (error) {
console.error('Error during fetch:', error);
}
}
</script>
</body>
</html>