import * as plugins from '../../plugins.js';
import * as fs from 'fs';
import * as path from 'path';
import { fileURLToPath } from 'url';
import { AsyncFileSystem } from '../../core/utils/fs-utils.js';
import type { ILogger, ICertificateEntry } from './models/types.js';

/**
 * Interface for default certificate data
 */
export interface IDefaultCertificates {
  key: string;
  cert: string;
}

/**
 * Provides default SSL certificates for HttpProxy.
 * This is a minimal replacement for the deprecated CertificateManager.
 *
 * For production certificate management, use SmartCertManager instead.
 */
export class DefaultCertificateProvider {
  private defaultCertificates: IDefaultCertificates | null = null;
  private certificateCache: Map<string, ICertificateEntry> = new Map();
  private initialized = false;

  constructor(private logger?: ILogger) {}

  /**
   * Load default certificates asynchronously (preferred)
   */
  public async loadDefaultCertificatesAsync(): Promise<IDefaultCertificates> {
    if (this.defaultCertificates) {
      return this.defaultCertificates;
    }

    const __dirname = path.dirname(fileURLToPath(import.meta.url));
    const certPath = path.join(__dirname, '..', '..', '..', 'assets', 'certs');

    try {
      const [key, cert] = await Promise.all([
        AsyncFileSystem.readFile(path.join(certPath, 'key.pem')),
        AsyncFileSystem.readFile(path.join(certPath, 'cert.pem'))
      ]);

      this.defaultCertificates = { key, cert };
      this.logger?.info?.('Loaded default certificates from filesystem');
      this.initialized = true;
      return this.defaultCertificates;
    } catch (error) {
      this.logger?.warn?.(`Failed to load default certificates: ${error}`);
      this.defaultCertificates = this.generateFallbackCertificate();
      this.initialized = true;
      return this.defaultCertificates;
    }
  }

  /**
   * Load default certificates synchronously (for backward compatibility)
   * @deprecated Use loadDefaultCertificatesAsync instead
   */
  public loadDefaultCertificatesSync(): IDefaultCertificates {
    if (this.defaultCertificates) {
      return this.defaultCertificates;
    }

    const __dirname = path.dirname(fileURLToPath(import.meta.url));
    const certPath = path.join(__dirname, '..', '..', '..', 'assets', 'certs');

    try {
      this.defaultCertificates = {
        key: fs.readFileSync(path.join(certPath, 'key.pem'), 'utf8'),
        cert: fs.readFileSync(path.join(certPath, 'cert.pem'), 'utf8')
      };
      this.logger?.info?.('Loaded default certificates from filesystem (sync)');
    } catch (error) {
      this.logger?.warn?.(`Failed to load default certificates: ${error}`);
      this.defaultCertificates = this.generateFallbackCertificate();
    }

    this.initialized = true;
    return this.defaultCertificates;
  }

  /**
   * Gets the default certificates (loads synchronously if not already loaded)
   */
  public getDefaultCertificates(): IDefaultCertificates {
    if (!this.defaultCertificates) {
      return this.loadDefaultCertificatesSync();
    }
    return this.defaultCertificates;
  }

  /**
   * Updates a certificate in the cache
   */
  public updateCertificate(domain: string, cert: string, key: string): void {
    this.certificateCache.set(domain, {
      cert,
      key,
      expires: new Date(Date.now() + 90 * 24 * 60 * 60 * 1000) // 90 days
    });

    this.logger?.info?.(`Certificate updated for ${domain}`);
  }

  /**
   * Gets a cached certificate
   */
  public getCachedCertificate(domain: string): ICertificateEntry | null {
    return this.certificateCache.get(domain) || null;
  }

  /**
   * Gets statistics for metrics
   */
  public getStats(): { cachedCertificates: number; defaultCertEnabled: boolean } {
    return {
      cachedCertificates: this.certificateCache.size,
      defaultCertEnabled: this.defaultCertificates !== null
    };
  }

  /**
   * Generate a fallback self-signed certificate placeholder
   * Note: This is just a placeholder - real apps should provide proper certificates
   */
  private generateFallbackCertificate(): IDefaultCertificates {
    this.logger?.warn?.('Using fallback self-signed certificate placeholder');

    // Minimal self-signed certificate for fallback only
    // In production, proper certificates should be provided via SmartCertManager
    const selfSignedCert = `-----BEGIN CERTIFICATE-----
MIIBkTCB+wIJAKHHIgIIA0/cMA0GCSqGSIb3DQEBBQUAMA0xCzAJBgNVBAYTAlVT
MB4XDTE0MDEwMTAwMDAwMFoXDTI0MDEwMTAwMDAwMFowDTELMAkGA1UEBhMCVVMw
gZ8wDQYJKoZIhvcNAQEBBQADgY0AMIGJAoGBAMRiH0VwnOH3jCV7c6JFZWYrvuqy
-----END CERTIFICATE-----`;

    const selfSignedKey = `-----BEGIN PRIVATE KEY-----
MIICdgIBADANBgkqhkiG9w0BAQEFAASCAmAwggJcAgEAAoGBAMRiH0VwnOH3jCV7
c6JFZWYrvuqyALCLXj0pcr1iqNdHjegNXnkl5zjdaUjq4edNOKl7M1AlFiYjG2xk
-----END PRIVATE KEY-----`;

    return {
      key: selfSignedKey,
      cert: selfSignedCert
    };
  }
}