const logger = require('../utils/logger');
const MessageTypes = require('./messageTypes');
const { clipboardService } = require('../services/clipboard');

class InputHandler {
  constructor(inputService) {
    this.inputService = inputService;
    this.clipboardService = clipboardService;
    this.eventQueue = [];
    this.isProcessingQueue = false;
    this.lastMouseMove = null;
    this.mouseMovePending = false;
  }

  handleMessage(message, ws) {
    const { type, ...data } = message;

    switch (type) {
      case MessageTypes.MOUSE_MOVE:
        this.queueMouseMove(data.x, data.y);
        break;
      case MessageTypes.MOUSE_DOWN:
        this.queueEvent('mouseDown', data.button || 'left');
        break;
      case MessageTypes.MOUSE_UP:
        this.queueEvent('mouseUp', data.button || 'left');
        break;
      case MessageTypes.MOUSE_WHEEL:
        this.queueEvent('mouseWheel', data.delta);
        break;
      case MessageTypes.KEY_DOWN:
        this.queueEvent('keyDown', data.key);
        break;
      case MessageTypes.KEY_UP:
        this.queueEvent('keyUp', data.key);
        break;
      case MessageTypes.CLIPBOARD_GET:
        this.handleClipboardGet(ws);
        break;
      case MessageTypes.CLIPBOARD_SET:
        this.handleClipboardSet(ws, data);
        break;
      default:
        logger.debug('Unknown message type', { type });
    }
  }

  async handleClipboardGet(ws) {
    try {
      const content = await this.clipboardService.read();
      if (this.clipboardService.isSmallContent(content.size)) {
        ws.send(JSON.stringify({
          type: MessageTypes.CLIPBOARD_DATA,
          contentType: content.type,
          data: content.data,
          size: content.size
        }));
      } else {
        ws.send(JSON.stringify({
          type: MessageTypes.CLIPBOARD_TOO_LARGE,
          size: content.size
        }));
      }
    } catch (error) {
      logger.error('Failed to get clipboard', { error: error.message });
      ws.send(JSON.stringify({
        type: MessageTypes.CLIPBOARD_RESULT,
        success: false
      }));
    }
  }

  async handleClipboardSet(ws, data) {
    try {
      const success = await this.clipboardService.set({
        type: data.contentType,
        data: data.data
      });
      ws.send(JSON.stringify({
        type: MessageTypes.CLIPBOARD_RESULT,
        success
      }));
    } catch (error) {
      logger.error('Failed to set clipboard', { error: error.message });
      ws.send(JSON.stringify({
        type: MessageTypes.CLIPBOARD_RESULT,
        success: false
      }));
    }
  }

  queueMouseMove(x, y) {
    this.lastMouseMove = { x, y };

    if (!this.mouseMovePending) {
      this.mouseMovePending = true;
      setImmediate(() => {
        if (this.lastMouseMove) {
          this.eventQueue.push({
            type: 'mouseMove',
            x: this.lastMouseMove.x,
            y: this.lastMouseMove.y
          });
          this.mouseMovePending = false;
          this.processQueue();
        }
      });
    }
  }

  queueEvent(type, data) {
    this.eventQueue.push({ type, data });
    this.processQueue();
  }

  async processQueue() {
    if (this.isProcessingQueue || this.eventQueue.length === 0) {
      return;
    }

    this.isProcessingQueue = true;

    while (this.eventQueue.length > 0) {
      const event = this.eventQueue.shift();
      await this.executeEvent(event);
    }

    this.isProcessingQueue = false;
  }

  async executeEvent(event) {
    try {
      switch (event.type) {
        case 'mouseMove':
          await this.inputService.mouseMove(event.x, event.y);
          break;
        case 'mouseDown':
          await this.inputService.mouseDown(event.data);
          break;
        case 'mouseUp':
          await this.inputService.mouseUp(event.data);
          break;
        case 'mouseWheel':
          await this.inputService.mouseWheel(event.data);
          break;
        case 'keyDown':
          await this.inputService.keyDown(event.data);
          break;
        case 'keyUp':
          await this.inputService.keyUp(event.data);
          break;
      }
    } catch (error) {
      logger.error('Failed to execute event', {
        type: event.type,
        error: error.message
      });
    }
  }

  stop() {
    logger.info('Stopping InputHandler');
    this.eventQueue = [];
    this.isProcessingQueue = false;
    this.lastMouseMove = null;
    this.mouseMovePending = false;
  }
}

module.exports = InputHandler;