bowling-analysis-system/src/core/ServiceContainer.js

A comprehensive system for analyzing bowling techniques using video processing and metrics calculation

/**
 * @fileoverview Service Container for dependency injection
 * @module core/ServiceContainer
 */

/**
 * Service Container for dependency injection
 */
class ServiceContainer {
  /**
   * Create a new service container
   */
  constructor() {
    this.services = new Map();
    this.instances = new Map();
  }

  /**
   * Register a service factory
   * @param {string} name - Service name
   * @param {Function} factory - Service factory function
   * @param {Object} options - Registration options
   * @returns {ServiceContainer} Container instance for chaining
   */
  singleton(name, factory, options = {}) {
    this.services.set(name, {
      factory,
      options,
      singleton: true
    });
    return this;
  }

  /**
   * Register a service factory that creates a new instance each time
   * @param {string} name - Service name
   * @param {Function} factory - Service factory function
   * @param {Object} options - Registration options
   * @returns {ServiceContainer} Container instance for chaining
   */
  transient(name, factory, options = {}) {
    this.services.set(name, {
      factory,
      options,
      singleton: false
    });
    return this;
  }

  /**
   * Register an instance
   * @param {string} name - Service name
   * @param {Object} instance - Service instance
   * @returns {ServiceContainer} Container instance for chaining
   */
  instance(name, instance) {
    this.instances.set(name, instance);
    return this;
  }

  /**
   * Get a service
   * @param {string} name - Service name
   * @returns {Object} Service instance
   */
  get(name) {
    // Return existing instance if available
    if (this.instances.has(name)) {
      return this.instances.get(name);
    }

    // Check if service is registered
    if (!this.services.has(name)) {
      throw new Error(`Service not registered: ${name}`);
    }

    const service = this.services.get(name);
    const instance = service.factory();

    // Store instance if singleton
    if (service.singleton) {
      this.instances.set(name, instance);
    }

    return instance;
  }

  /**
   * Check if a service is registered
   * @param {string} name - Service name
   * @returns {boolean} Whether the service is registered
   */
  has(name) {
    return this.services.has(name) || this.instances.has(name);
  }

  /**
   * Remove a service
   * @param {string} name - Service name
   * @returns {boolean} Whether the service was removed
   */
  remove(name) {
    this.instances.delete(name);
    return this.services.delete(name);
  }
}

// Create default container
const defaultContainer = new ServiceContainer();

module.exports = {
  ServiceContainer,
  defaultContainer
};