License Keys

// Generate a unique device fingerprint
// You can use libraries like fingerprintjs2 or create your own
function getDeviceFingerprint() {
  // Example using machine ID, OS, and hardware info
  const components = [
    navigator.userAgent,
    navigator.platform,
    // Add more hardware-specific identifiers
  ];

  return btoa(components.join('|'));
}

async function activateDevice(licenseKey) {
  const deviceFingerprint = getDeviceFingerprint();
  const deviceName = `${navigator.platform} - ${new Date().toISOString()}`;

  const response = await fetch('https://yourplatform.com/api/licenses/activate', {
    method: 'POST',
    headers: { 'Content-Type': 'application/json' },
    body: JSON.stringify({
      licenseKey,
      deviceFingerprint,
      deviceName
    })
  });

  const result = await response.json();

  if (!result.success) {
    throw new Error(result.error || 'Activation failed');
  }

  return result;
}

// Usage
try {
  const activation = await activateDevice('XXXX-XXXX-XXXX-XXXX');
  console.log('Device activated:', activation.activation.deviceName);
  console.log('Activations used:', activation.activationsUsed, '/', activation.activationsAllowed);
} catch (error) {
  if (error.message.includes('Maximum device limit')) {
    console.error('All device slots are used. Please deactivate a device first.');
  } else {
    console.error('Activation failed:', error.message);
  }
}

class LicenseManager {
  constructor(baseUrl) {
    this.baseUrl = baseUrl;
    this.licenseKey = localStorage.getItem('licenseKey');
    this.deviceFingerprint = this.getDeviceFingerprint();
  }

  getDeviceFingerprint() {
    // Store or generate device fingerprint
    let fingerprint = localStorage.getItem('deviceFingerprint');
    if (!fingerprint) {
      fingerprint = this.generateFingerprint();
      localStorage.setItem('deviceFingerprint', fingerprint);
    }
    return fingerprint;
  }

  generateFingerprint() {
    // Implement your fingerprint logic
    return btoa(navigator.userAgent + navigator.platform);
  }

  async validateAndActivate(licenseKey) {
    // First, validate the license
    const validation = await this.validate(licenseKey);

    if (!validation.valid) {
      throw new Error(validation.error);
    }

    // Check if this device is already activated
    if (!validation.device.isDeviceActivated) {
      // Activate this device
      await this.activate(licenseKey);
    }

    // Store license key
    this.licenseKey = licenseKey;
    localStorage.setItem('licenseKey', licenseKey);

    return validation;
  }

  async validate(licenseKey) {
    const response = await fetch(`${this.baseUrl}/api/licenses/validate`, {
      method: 'POST',
      headers: { 'Content-Type': 'application/json' },
      body: JSON.stringify({
        licenseKey: licenseKey || this.licenseKey,
        deviceFingerprint: this.deviceFingerprint
      })
    });

    return await response.json();
  }

  async activate(licenseKey) {
    const response = await fetch(`${this.baseUrl}/api/licenses/activate`, {
      method: 'POST',
      headers: { 'Content-Type': 'application/json' },
      body: JSON.stringify({
        licenseKey,
        deviceFingerprint: this.deviceFingerprint,
        deviceName: navigator.platform
      })
    });

    const result = await response.json();
    if (!result.success) {
      throw new Error(result.error);
    }

    return result;
  }

  async deactivate() {
    if (!this.licenseKey) {
      throw new Error('No license key found');
    }

    const response = await fetch(`${this.baseUrl}/api/licenses/deactivate`, {
      method: 'POST',
      headers: { 'Content-Type': 'application/json' },
      body: JSON.stringify({
        licenseKey: this.licenseKey,
        deviceFingerprint: this.deviceFingerprint
      })
    });

    const result = await response.json();
    if (!result.success) {
      throw new Error(result.error);
    }

    // Clear stored license
    localStorage.removeItem('licenseKey');
    this.licenseKey = null;

    return result;
  }
}

// Usage
const licenseManager = new LicenseManager('https://yourplatform.com');

// On app startup
async function initializeApp() {
  try {
    if (licenseManager.licenseKey) {
      // Validate existing license
      const validation = await licenseManager.validate();
      console.log('License valid:', validation.productName);
    } else {
      // Prompt user for license key
      const userLicenseKey = prompt('Enter your license key:');
      await licenseManager.validateAndActivate(userLicenseKey);
      console.log('License activated successfully!');
    }
  } catch (error) {
    console.error('License error:', error.message);
    // Handle error (show UI, etc.)
  }
}

initializeApp();