import { ipcMain } from 'electron';
import { exec } from 'child_process';
import { promisify } from 'util';
import { getCachedAdbPath } from '../config.js';

const execAsync = promisify(exec);

// 默认每次滚动距离（像素）
const DEFAULT_SCROLL_DISTANCE = 100;
// 默认滚动持续时间（毫秒），使用较长的时间模拟真实手指滑动
const DEFAULT_SCROLL_DURATION = 500;

/**
 * 计算滚动操作的坐标（小幅度滚动）
 * @param {string} direction - 滚动方向: up-down, down-up, left-right, right-left
 * @param {number} width - 设备宽度
 * @param {number} height - 设备高度
 * @param {number} scrollDistance - 每次滚动距离（像素），默认10px
 * @returns {Object} 包含起始和结束坐标的对象 {x1, y1, x2, y2}
 */
function calculateScrollCoordinates(direction, width, height, scrollDistance = DEFAULT_SCROLL_DISTANCE) {
  // 滚动从屏幕中心开始
  const centerX = Math.round(width / 2);
  const centerY = Math.round(height / 2);

  let x1, y1, x2, y2;

  switch (direction) {
    case 'up-down':
      // 从上往下滚动（向下滚动）
      x1 = x2 = centerX;
      y1 = centerY;
      y2 = centerY + scrollDistance;
      break;
    
    case 'down-up':
      // 从下往上滚动（向上滚动）
      x1 = x2 = centerX;
      y1 = centerY;
      y2 = centerY - scrollDistance;
      break;
    
    case 'left-right':
      // 从左往右滚动（向右滚动）
      y1 = y2 = centerY;
      x1 = centerX;
      x2 = centerX + scrollDistance;
      break;
    
    case 'right-left':
      // 从右往左滚动（向左滚动）
      y1 = y2 = centerY;
      x1 = centerX;
      x2 = centerX - scrollDistance;
      break;
    
    default:
      throw new Error(`未知的滚动方向: ${direction}`);
  }

  return { x1, y1, x2, y2 };
}

/**
 * 发送滚动操作到设备
 * 使用触摸屏事件模拟真实的手指滑动，避免触发 tap 事件
 * @param {string} ipPort - 设备 ID
 * @param {string} direction - 滚动方向: up-down, down-up, left-right, right-left
 * @param {number} width - 设备宽度
 * @param {number} height - 设备高度
 * @param {number} scrollDistance - 每次滚动距离（像素），默认10px
 * @param {number} duration - 滚动持续时间（毫秒），默认500ms
 * @returns {Promise<Object>} 执行结果 {success, error?}
 */
export async function sendScroll(ipPort, direction, width, height, scrollDistance = DEFAULT_SCROLL_DISTANCE, duration = DEFAULT_SCROLL_DURATION) {
  if (!ipPort) {
    return { success: false, error: '缺少设备 ID' };
  }
  
  if (!direction) {
    return { success: false, error: '缺少滚动方向' };
  }
  
  const validDirections = ['up-down', 'down-up', 'left-right', 'right-left'];
  if (!validDirections.includes(direction)) {
    return { success: false, error: `无效的滚动方向: ${direction}，应为: ${validDirections.join(', ')}` };
  }
  
  if (typeof width !== 'number' || typeof height !== 'number') {
    return { success: false, error: '设备宽度和高度必须是数字' };
  }
  
  if (width <= 0 || height <= 0) {
    return { success: false, error: '设备宽度和高度必须大于0' };
  }
  
  try {
    const adbPath = getCachedAdbPath();
    
    // 计算滚动坐标
    const { x1, y1, x2, y2 } = calculateScrollCoordinates(direction, width, height, scrollDistance);
    
    // 使用 input touchscreen swipe 命令来模拟真实的触摸滑动
    // 这个命令会模拟手指在屏幕上慢慢滑动，不会触发 tap 事件
    // 使用较长的持续时间（至少 300ms）确保被识别为滑动而不是点击
    const actualDuration = Math.max(duration, 300); // 确保至少 300ms
    
    const command = `${adbPath} -s ${ipPort} shell input touchscreen swipe ${x1} ${y1} ${x2} ${y2} ${actualDuration}`;
    
    await execAsync(command, {
      timeout: 10000,
      maxBuffer: 1024 * 1024
    });
    
    return { success: true };
  } catch (error) {
    return { success: false, error: error.message };
  }
}

// 注册 IPC 处理器
export function registerIpcHandlers() {
  // IPC 处理程序：发送滚动操作到设备
  ipcMain.handle('send-scroll', async (event, ipPort, direction, width, height, scrollDistance, duration) => {
    return await sendScroll(ipPort, direction, width, height, scrollDistance, duration);
  });
}