cs2-gsi-z/src/core/handlers/GsiUpdateHandler.js

A modular, event-driven Game State Integration (GSI) handler for Counter-Strike 2 built with Node.js.

import { GsiParser } from "../parser/GsiParser.js";
import { applyDelta } from '../../utils/applyDelta.js';

export class GsiUpdateHandler {
  constructor({ logger, stateManager, differManager, emitter }) {
    this.logger = (logger ?? { child: () => console }).child('GsiupdateHandler');
    this.stateManager = stateManager;
    this.differManager = differManager;
    this.emitter = emitter;

    this.logger.log('⚙️ instantiated correctly.');
  }

  handle(rawJson) {
    if (!rawJson) {
      this.logger.warn('⚠️ Empty GSI payload received.');
      return;
    }

    this.logger.log('🔔 GSI update received.');

    try {
      const parsedState = new GsiParser(rawJson).parse();
      this.logger.log('🧩 State parsed.');

      const previousState = this.stateManager.getFullState();

      if (previousState?.player) {
        this.logger.verbose('🔄 Previous complete state:');
        this.logger.verbose(JSON.stringify(previousState, null, 2));

        applyDelta(parsedState, rawJson.previously);

        this.logger.verbose('🔁 State after applying delta:');
        this.logger.verbose(JSON.stringify(parsedState, null, 2));

        this.logger.log('🔀 Delta applied.');

        this.differManager.diff(previousState, parsedState, {
          emit: (event, payload) => {
            this.logger.log(`🛎️ Event detected: ${event}`, payload);
            this.emitter.emit(event, payload);
          }
        });
      }

      this.stateManager.setFullState(parsedState);
      this.logger.log('📦 Snapshot updated in GameStateManager.');

    } catch (error) {
      this.logger.error('❌ Error processing GSI update:', error);
    }
  }
}