import type { ISignalingClient } from '../interfaces/ISignalingClient';
import type { IPeerConnectionOperations } from '../interfaces/IPeerConnectionOperations';
import type { ILogger } from '@techniker-me/logger';
import { LoggerFactory } from '@techniker-me/logger';

/**
 * Caller class - responsible for initiating WebRTC calls
 * Follows Single Responsibility Principle - only handles offer creation flow
 * Follows Dependency Inversion Principle - depends on abstractions (interfaces)
 */
export class Caller {
  private readonly _logger: ILogger = LoggerFactory.getLogger('Caller');
  private readonly _signalingClient: ISignalingClient;
  private readonly _peerConnection: IPeerConnectionOperations;

  constructor(
    signalingClient: ISignalingClient,
    peerConnection: IPeerConnectionOperations
  ) {
    this._signalingClient = signalingClient;
    this._peerConnection = peerConnection;
  }

  /**
   * Create and send an offer following the sequence diagram:
   * 1. Create Offer
   * 2. Set local description to offer
   * 3. Send Offer to signaling server
   */
  public async createAndSendOffer(): Promise<void> {
    try {
      this._logger.info('Creating offer...');
      
      // Step 1: Create Offer
      const offer = await this._peerConnection.createOffer();
      
      // Step 2: Set local description to offer
      await this._peerConnection.setLocalDescription(offer);
      this._logger.info('Local description set to offer');
      
      // Step 3: Send Offer to signaling server
      await this._signalingClient.sendOffer(offer);
      this._logger.info('Offer sent to signaling server');
    } catch (error) {
      this._logger.error('Failed to create and send offer', error);
      throw error;
    }
  }

  /**
   * Handle receiving an answer from the callee
   * Sets the answer as remote description
   */
  public async handleAnswer(answer: RTCSessionDescriptionInit): Promise<void> {
    try {
      this._logger.info('Handling answer from callee...');
      
      // Set Answer as remote description
      await this._peerConnection.setRemoteDescription(answer);
      this._logger.info('Answer set as remote description');
    } catch (error) {
      this._logger.error('Failed to handle answer', error);
      throw error;
    }
  }
}