paymentController.js

/**
 * src/controllers/paymentController.js
 * Handles payment history and stats requests.
 */

"use strict";

const stellarService = require("../services/stellarService");

/**
 * @typedef {object} PaymentRecord
 * @property {string} id
 * @property {"sent"|"received"} type
 * @property {string} amount
 * @property {string} asset
 * @property {string} from
 * @property {string} to
 * @property {string} createdAt
 * @property {string} transactionHash
 * @property {string} pagingToken
 * @property {string} [memo]
 */

/**
 * GET /api/payments/:publicKey
 *
 * @param {object} req - Express request
 * @param {object} req.params
 * @param {string} req.params.publicKey - Stellar public key (G...)
 * @param {object} req.query
 * @param {string} [req.query.limit] - Max records to return (1-100, default 20)
 * @param {string} [req.query.cursor] - Horizon paging token to continue from
 * @param {object} res - Express response
 * @param {function} next - Express error-handling callback
 * @returns {Promise<void>} JSON: `{ success: true, data: PaymentRecord[] }`,
 *   or 400 JSON: `{ error: string }` when limit is not a positive integer
 */
async function getPayments(req, res, next) {
  try {
    const { publicKey } = req.params;

    // #197: explicit validation — || 20 silently swallows limit=0; NaN propagates to Horizon
    const rawLimit = req.query.limit;
    let limit = 20;
    if (rawLimit !== undefined) {
      const parsed = parseInt(rawLimit, 10);
      if (isNaN(parsed) || !Number.isSafeInteger(parsed) || parsed < 1) {
        return res.status(400).json({ error: "limit must be a positive integer" });
      }
      limit = Math.min(parsed, 100);
    }

    const cursor = req.query.cursor || undefined;

    const payments = await stellarService.getPayments(publicKey, { limit, cursor });
    res.json({ success: true, data: payments });
  } catch (err) {
    next(err);
  }
}

/**
 * GET /api/payments/:publicKey/stats
 * Computes aggregate payment statistics for a wallet.
 *
 * @param {object} req - Express request
 * @param {object} req.params
 * @param {string} req.params.publicKey - Stellar public key (G...)
 * @param {object} res - Express response
 * @param {function} next - Express error-handling callback
 * @returns {Promise<void>} JSON: `{ success: true, data: { publicKey: string, totalSentXLM: string,
 *   totalReceivedXLM: string, sentCount: number, receivedCount: number, totalTransactions: number } }`
 */
async function getStats(req, res, next) {
  try {
    const { publicKey } = req.params;
    const payments = await stellarService.getPayments(publicKey, { limit: 100 });

    let totalSent = 0;
    let totalReceived = 0;
    let sentCount = 0;
    let receivedCount = 0;

    for (const p of payments) {
      if (p.type === "sent") {
        totalSent += parseFloat(p.amount);
        sentCount++;
      } else {
        totalReceived += parseFloat(p.amount);
        receivedCount++;
      }
    }

    res.json({
      success: true,
      data: {
        publicKey,
        totalSentXLM: totalSent.toFixed(7),
        totalReceivedXLM: totalReceived.toFixed(7),
        sentCount,
        receivedCount,
        totalTransactions: sentCount + receivedCount,
      },
    });
  } catch (err) {
    next(err);
  }
}

module.exports = { getPayments, getStats };