Refactor: move services to components, add route modules

Co-authored-by: Cursor <cursoragent@cursor.com>

routes/redemption.js

@@ -0,0 +1,146 @@
+const express = require('express');
+const router = express.Router();
+const redemption = require('../components/redemption');
+
+/**
+ * @swagger
+ * /api/redeem:
+ *   post:
+ *     summary: Redeem a Cashu token to Lightning address
+ *     description: |
+ *       Redeem a Cashu token to a Lightning address (optional - uses default if not provided).
+ *       
+ *       The redemption process includes:
+ *       1. Token validation and parsing
+ *       2. Getting exact melt quote from mint to determine precise fees
+ *       3. Invoice creation for net amount (token amount - exact fees)
+ *       4. Spendability checking at the mint
+ *       5. Token melting and Lightning payment
+ *       
+ *       **Important**: The system gets the exact fee from the mint before creating the invoice.
+ *       The `invoiceAmount` field shows the actual amount sent to the Lightning address.
+ *       No sats are lost to fee estimation errors.
+ *     tags: [Token Operations]
+ *     requestBody:
+ *       required: true
+ *       content:
+ *         application/json:
+ *           schema:
+ *             $ref: '#/components/schemas/RedeemRequest'
+ *     responses:
+ *       200:
+ *         description: Token redeemed successfully
+ *         content:
+ *           application/json:
+ *             schema:
+ *               $ref: '#/components/schemas/RedeemResponse'
+ *       400:
+ *         $ref: '#/components/responses/BadRequest'
+ *       409:
+ *         description: Token already spent
+ *         content:
+ *           application/json:
+ *             schema:
+ *               type: object
+ *               properties:
+ *                 success:
+ *                   type: boolean
+ *                   example: false
+ *                 error:
+ *                   type: string
+ *                   example: "This token has already been spent and cannot be redeemed again"
+ *                 errorType:
+ *                   type: string
+ *                   example: "token_already_spent"
+ *       422:
+ *         description: Insufficient funds or unprocessable token
+ *         content:
+ *           application/json:
+ *             schema:
+ *               type: object
+ *               properties:
+ *                 success:
+ *                   type: boolean
+ *                   example: false
+ *                 error:
+ *                   type: string
+ *                   example: "Token amount is insufficient to cover the minimum fee"
+ *                 errorType:
+ *                   type: string
+ *                   example: "insufficient_funds"
+ *       429:
+ *         $ref: '#/components/responses/TooManyRequests'
+ *       500:
+ *         $ref: '#/components/responses/InternalServerError'
+ */
+router.post('/redeem', async (req, res) => {
+  const { token, lightningAddress } = req.body;
+
+  const validation = await redemption.validateRedemptionRequest(token, lightningAddress);
+  
+  if (!validation.valid) {
+    return res.status(400).json({
+      success: false,
+      error: validation.errors.join(', ')
+    });
+  }
+
+  try {
+    const result = await redemption.performRedemption(token, lightningAddress);
+    
+    if (result.success) {
+      const response = {
+        success: true,
+        paid: result.paid,
+        amount: result.amount,
+        invoiceAmount: result.invoiceAmount,
+        to: result.to,
+        fee: result.fee,
+        actualFee: result.actualFee,
+        netAmount: result.netAmount,
+        mint_url: result.mint,
+        format: result.format
+      };
+
+      if (result.usingDefaultAddress) {
+        response.usingDefaultAddress = true;
+        response.message = `Redeemed to default Lightning address: ${result.to}`;
+      }
+
+      if (result.preimage) {
+        response.preimage = result.preimage;
+      }
+
+      res.json(response);
+    } else {
+      let statusCode = 400;
+      
+      if (result.error && (
+        result.error.includes('cannot be redeemed') ||
+        result.error.includes('already been used') ||
+        result.error.includes('not spendable') ||
+        result.error.includes('already spent') ||
+        result.error.includes('invalid proofs')
+      )) {
+        statusCode = 409;
+      } else if (result.error && result.error.includes('insufficient')) {
+        statusCode = 422;
+      }
+      
+      res.status(statusCode).json({
+        success: false,
+        error: result.error,
+        errorType: statusCode === 409 ? 'token_already_spent' : 
+                   statusCode === 422 ? 'insufficient_funds' : 'validation_error'
+      });
+    }
+  } catch (error) {
+    console.error('Error in redemption:', error);
+    res.status(500).json({
+      success: false,
+      error: 'Internal server error during redemption'
+    });
+  }
+});
+
+module.exports = router;