const express = require('express');
const rateLimit = require('express-rate-limit');
const { success, error: errorResponse } = require('../src/utils/responses');
const { ValidationError } = require('../src/utilities/errors');

// Dedicated rate limiter for license activation — prevents brute-force key guessing.
// Pro keys follow a predictable format (DC-XXX-XXXXX-XXXXXX), so without rate
// limiting an attacker could enumerate valid keys.
const licenseActivateLimiter = rateLimit({
  windowMs: 15 * 60 * 1000, // 15 minutes
  max: 10,                   // 10 attempts per window per IP
  standardHeaders: true,
  legacyHeaders: false,
  message: { success: false, error: 'Too many license activation attempts. Please try again later.' },
  skip: () => process.env.NODE_ENV === 'test',
});

/**
 * License routes factory
 * @param {Object} deps - Explicit dependencies
 * @param {Object} deps.licenseManager - License management module
 * @param {Function} deps.asyncHandler - Async route handler wrapper
 * @returns {express.Router}
 */
module.exports = function({ licenseManager, asyncHandler }) {
  const router = express.Router();

  // Activate a license code
  router.post('/activate', licenseActivateLimiter, asyncHandler(async (req, res) => {
    const { code } = req.body;
    if (!code) {
      throw new ValidationError('License code is required');
    }

    const result = await licenseManager.activate(code);

    if (result.success) {
      success(res, {
        message: result.message,
        license: result.activation
      });
    } else {
      errorResponse(res, result.message, 400);
    }
  }, 'license-activate'));

  // Get current license status
  router.get('/status', asyncHandler(async (req, res) => {
    await licenseManager.refreshOnline?.();
    const status = licenseManager.getStatus();
    success(res, { license: status });
  }, 'license-status'));

  // Deactivate current license
  router.post('/deactivate', asyncHandler(async (req, res) => {
    const result = await licenseManager.deactivate();

    if (result.success) {
      success(res, { message: result.message });
    } else {
      errorResponse(res, result.message, 400);
    }
  }, 'license-deactivate'));

  // Check if a specific feature is available (lightweight check for frontend)
  router.get('/feature/:feature', asyncHandler(async (req, res) => {
    const { feature } = req.params;
    const available = licenseManager.hasFeature(feature);
    const status = licenseManager.getStatus();

    success(res, {
      feature,
      available,
      tier: status.tier,
      ...(available ? {} : {
        upgradeUrl: '/settings#license',
        message: `${status.premiumFeatures[feature]?.name || feature} requires DashCaddy Premium`
      })
    });
  }, 'license-feature-check'));

  return router;
};