'use strict';

/**
 * Partner Service Factory
 * Dynamically loads and creates partner services based on partner code
 */

class PartnerServiceFactory {
  constructor() {
    this.services = new Map();
    this.serviceMapping = {
      'SATLOC': '../services/satloc_service',
      // Add more partner services here as they're implemented
      // 'AGIDRONEX': '../services/agidronex_service',
      // 'OTHERPARTER': '../services/other_partner_service'
    };
  }

  /**
   * Get partner service instance
   * @param {string} partnerCode - Partner code (e.g., 'SATLOC')
   * @returns {object} Partner service instance
   */
  getService(partnerCode) {
    // Check if service is already instantiated
    if (this.services.has(partnerCode)) {
      return this.services.get(partnerCode);
    }

    // Check if service mapping exists
    const servicePath = this.serviceMapping[partnerCode];
    if (!servicePath) {
      throw new Error(`Partner service not implemented for: ${partnerCode}`);
    }

    try {
      // Dynamically require and instantiate the service
      const ServiceClass = require(servicePath);
      const serviceInstance = new ServiceClass();
      
      // Cache the instance for reuse
      this.services.set(partnerCode, serviceInstance);
      
      return serviceInstance;
    } catch (error) {
      throw new Error(`Failed to load partner service for ${partnerCode}: ${error.message}`);
    }
  }

  /**
   * Check if a partner service is available
   * @param {string} partnerCode - Partner code
   * @returns {boolean} True if service is available
   */
  hasService(partnerCode) {
    return this.serviceMapping.hasOwnProperty(partnerCode);
  }

  /**
   * Get list of supported partner codes
   * @returns {string[]} Array of supported partner codes
   */
  getSupportedPartners() {
    return Object.keys(this.serviceMapping);
  }

  /**
   * Register a new partner service (for dynamic registration)
   * @param {string} partnerCode - Partner code
   * @param {string} servicePath - Path to service module
   */
  registerService(partnerCode, servicePath) {
    this.serviceMapping[partnerCode] = servicePath;
  }

  /**
   * Fetch log file from partner storage using appropriate service
   * @param {string} logFileName - Name of the log file to fetch
   * @param {string} partnerCode - Partner code (e.g., 'SATLOC')
   * @returns {Promise<Object>} Log file data with content buffer
   */
  async fetchLogFile(logFileName, partnerCode) {
    const service = this.getService(partnerCode);
    
    if (typeof service.fetchLogFile !== 'function') {
      throw new Error(`Partner service ${partnerCode} does not support fetchLogFile method`);
    }
    
    return await service.fetchLogFile(logFileName, partnerCode);
  }
}

// Export singleton instance
module.exports = new PartnerServiceFactory();