### Install eupago-integration

Source: https://github.com/rafaelferreiratvd/eupago-integration/blob/master/README.md

Install the eupago-integration package using npm.

```bash
npm install --save eupago-integration
```

--------------------------------

### Create EuPago Payment Reference in Express.js

Source: https://context7.com/rafaelferreiratvd/eupago-integration/llms.txt

Use this snippet to create a payment reference for EuPago. Ensure the 'eupago-integration' library is installed and the EUPAGO_API_KEY environment variable is set. It handles amount validation and processes payment requests via POST to '/api/checkout'.

```javascript
const express = require('express');
const eupago = require('eupago-integration')();

const app = express();
app.use(express.json());

app.post('/api/checkout', async (req, res) => {
  const { amount, orderId, paymentMethod, phoneNumber } = req.body;

  try {
    // Validate amount
    if (isNaN(parseFloat(amount)) || amount <= 0) {
      return res.status(400).json({ error: 'Invalid amount' });
    }

    // Create payment reference
    const response = await eupago.createPaymentReference(
      amount,
      orderId,
      paymentMethod,
      phoneNumber  // Required for 'mbway' method
    );

    if (response.sucesso) {
      res.json({
        success: true,
        reference: response.referencia,
        entity: response.entidade,
        amount: response.valor
      });
    } else {
      res.status(400).json({
        success: false,
        error: response.resposta
      });
    }
  } catch (error) {
    res.status(500).json({
      success: false,
      error: error.message
    });
  }
});

app.listen(3000, () => {
  console.log('Server running on port 3000');
});
```

--------------------------------

### Configure EuPago Environment Variables

Source: https://context7.com/rafaelferreiratvd/eupago-integration/llms.txt

Set the required API key and optional configuration variables in your environment.

```bash
# Required
export EUPAGO_API_KEY=xxxx-xxxx-xxxx-xxxx-xxxx

# Optional (with defaults shown)
export EUPAGO_REST_API_URL=https://clientes.eupago.pt/clientes/rest_api
export EUPAGO_DESCRIPTION_MBWAY="Your purchase at Store"
export EUPAGO_ALLOW_DUPLICATED_PAYMENTS=0
```

--------------------------------

### Create Payment Reference

Source: https://github.com/rafaelferreiratvd/eupago-integration/blob/master/README.md

Use the eupago-integration library to create a payment reference. Ensure you have configured your EUPAGO_API_KEY.

```javascript
const eupago = require('eupago-integration')();
eupago.createPaymentReference(totalAmount, yourReference, method, mobilePhoneNumber).then((response) => {
    console.log(response)
});
```

--------------------------------

### Define Payment Method Configurations

Source: https://context7.com/rafaelferreiratvd/eupago-integration/llms.txt

View the internal configuration mapping for supported payment methods and their respective API endpoints.

```javascript
// Payment method configurations
const paymentMethods = {
  // Multibanco (Portuguese ATM network)
  mb: {
    endpoint: '/multibanco/create',
    fields: ['data_inicio', 'data_fim', 'valor_minimo', 'valor_maximo', 'per_dup']
  },

  // MB WAY (Mobile payments)
  mbway: {
    endpoint: '/mbway/create',
    fields: ['alias', 'descricao']  // alias = phone number
  },

  // Payshop (Payment terminals)
  payshop: {
    endpoint: '/payshop/create',
    fields: []
  },

  // PaySafeCard (Prepaid vouchers)
  paysafecard: {
    endpoint: '/paysafecard/create',
    fields: ['url_retorno']  // return URL after payment
  }
};
```

--------------------------------

### Create Payment References

Source: https://context7.com/rafaelferreiratvd/eupago-integration/llms.txt

Generate payment references for different methods using the createPaymentReference function.

```javascript
const eupago = require('eupago-integration')();

// Create a Multibanco payment reference
eupago.createPaymentReference(29.99, 'ORDER-12345', 'mb')
  .then((response) => {
    console.log('Multibanco Reference:', response);
    // Expected response:
    // {
    //   sucesso: true,
    //   estado: 0,
    //   resposta: 'OK',
    //   referencia: '123 456 789',
    //   entidade: '12345',
    //   valor: 29.99
    // }
  })
  .catch((error) => {
    console.error('Payment creation failed:', error.message);
  });

// Create an MB WAY payment reference with phone number
eupago.createPaymentReference(15.50, 'ORDER-67890', 'mbway', '351912345678')
  .then((response) => {
    console.log('MB WAY Reference:', response);
    // Expected response:
    // {
    //   sucesso: true,
    //   estado: 0,
    //   resposta: 'OK',
    //   referencia: 'MBWAY-REF-123',
    //   valor: 15.50
    // }
  })
  .catch((error) => {
    console.error('MB WAY payment failed:', error.message);
  });

// Create a Payshop payment reference
eupago.createPaymentReference(50.00, 'ORDER-11111', 'payshop')
  .then((response) => {
    console.log('Payshop Reference:', response);
  })
  .catch((error) => {
    console.error('Payshop payment failed:', error.message);
  });

// Create a PaySafeCard payment reference
eupago.createPaymentReference(100.00, 'ORDER-22222', 'paysafecard')
  .then((response) => {
    console.log('PaySafeCard Reference:', response);
  })
  .catch((error) => {
    console.error('PaySafeCard payment failed:', error.message);
  });
```

--------------------------------

### createPaymentReference

Source: https://context7.com/rafaelferreiratvd/eupago-integration/llms.txt

Generates a payment reference for a specified payment method using the EuPago API.

```APIDOC
## createPaymentReference

### Description
Creates a payment reference for the specified payment method (Multibanco, MB WAY, Payshop, or PaySafeCard).

### Parameters
- **amount** (number) - Required - The payment amount.
- **referenceId** (string) - Required - Internal reference ID.
- **method** (string) - Required - Payment method: 'mb', 'mbway', 'payshop', or 'paysafecard'.
- **alias** (string) - Optional - Phone number alias for MB WAY payments.

### Response
#### Success Response (200)
- **sucesso** (boolean) - Indicates if the request was successful.
- **estado** (number) - Status code.
- **resposta** (string) - Response message.
- **referencia** (string) - Generated payment reference.
- **entidade** (string) - Entity code (for Multibanco).
- **valor** (number) - The payment amount.

### Response Example
{
  "sucesso": true,
  "estado": 0,
  "resposta": "OK",
  "referencia": "123 456 789",
  "entidade": "12345",
  "valor": 29.99
}
```

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