import { EventEmitter } from 'events'
import pLimit from 'p-limit' // 建议使用 v2.2.0 以兼容 CJS
import { readingReflectionGraph } from '@main/services/ai/graph/readingReflectionGraph'
import { AppDataSource } from '@main/db/data-source'
import { ReadingReflectionTaskBatch } from '@main/db/entities/ReadingReflectionTaskBatch'
import { ReadingReflectionTaskItem } from '@main/db/entities/ReadingReflectionTaskItem'
import Store from 'electron-store'
import { CONFIG_STORE_KEY } from '@rpc/constants/store_key'
import { Notification } from 'electron'

export const readingReflectionTaskEvent = new EventEmitter()

// 兼容性处理获取 Store 构造函数
const StoreClass = (Store as any).default || Store
const store = new StoreClass({ encryptionKey: CONFIG_STORE_KEY })

class TaskManager {
  private limit = pLimit(2)
  private batchRepo = AppDataSource.getRepository(ReadingReflectionTaskBatch)
  private itemRepo = AppDataSource.getRepository(ReadingReflectionTaskItem)

  /**
   * 更新主任务汇总进度
   */
  private async updateBatchStatus(batchId: string) {
    const items = await this.itemRepo.find({ where: { batch: { id: batchId } } })
    if (items.length === 0) return

    const avgProgress = Math.round(items.reduce((acc, i) => acc + i.progress, 0) / items.length)
    let status = 'PROCESSING'
    if (avgProgress === 100) status = 'COMPLETED'
    if (items.every((i) => i.status === 'FAILED')) status = 'FAILED'

    await this.batchRepo.update(batchId, { progress: avgProgress, status })

    // 发送给左侧列表订阅者
    readingReflectionTaskEvent.emit('batchProgressUpdate', {
      batchId,
      progress: avgProgress,
      status
    })
  }

  async startBatchTask(taskId: string, task: any) {
    const total = task.quantity || 1

    // 1. 初始化主任务
    const batch = this.batchRepo.create({ id: taskId, bookName: task.bookName, totalCount: total })
    await this.batchRepo.save(batch)
    // 发送给左侧列表订阅者
    readingReflectionTaskEvent.emit('batchProgressUpdate', {
      batchId: taskId,
      progress: 0,
      status: 'PROCESSING'
    })

    const promises = Array.from({ length: total }).map((_, index) => {
      const subTaskId = total === 1 ? taskId : `${taskId}-${index}`

      return this.limit(async () => {
        try {
          const item = this.itemRepo.create({ id: subTaskId, batch: batch, status: 'PENDING' })
          await this.itemRepo.save(item)

          const stream = await readingReflectionGraph.stream(
            { ...task },
            { configurable: { thread_id: subTaskId } }
          )

          let finalResult: any = {}

          for await (const chunk of stream) {
            // 处理生成正文节点
            if (chunk.generateReadingReflectionContent) {
              const contentData = chunk.generateReadingReflectionContent
              await this.itemRepo.update(subTaskId, {
                status: 'WRITING',
                progress: 50,
                content: contentData.content,
                title: contentData.title
              })
              finalResult = { ...finalResult, ...contentData }
              await this.updateBatchStatus(taskId)
              this.emitProgress(taskId, index, total, 60, '正文已生成...')
            }

            // 处理生成摘要节点
            if (chunk.generateReadingReflectionSummary) {
              const summaryData = chunk.generateReadingReflectionSummary
              finalResult = { ...finalResult, ...summaryData }
              await this.itemRepo.update(subTaskId, {
                status: 'COMPLETED',
                progress: 100,
                summary: summaryData.summary,
                title: finalResult.title,
                keywords: summaryData.keywords
              })
            }
          }

          await this.updateBatchStatus(taskId)
          this.emitProgress(taskId, index, total, 100, '生成成功', finalResult)
        } catch (error) {
          await this.itemRepo.update(subTaskId, { status: 'FAILED', progress: 0 })
          await this.updateBatchStatus(taskId)
          this.emitProgress(taskId, index, total, 0, '生成失败')
        }
      })
    })

    await Promise.all(promises)
  }

  private emitProgress(
    taskId: string,
    index: number,
    total: number,
    progress: number,
    status: string,
    result?: any
  ) {
    const displayId = total === 1 ? taskId : `${taskId}-${index}`
    //发送 tRPC 实时事件（驱动前端 UI 进度条）
    readingReflectionTaskEvent.emit('readingReflectionTaskProgress', {
      taskId: displayId,
      progress,
      status: status, // 传枚举 Key
      statusText: `[任务${index + 1}/${total}] ${status}`, // 传描述文字
      result
    })
    // 2. 添加任务状态通知判断
    this.handleNotification(status, progress, total, index)
  }
  /**
   * 内部私有方法：处理通知逻辑
   */
  private handleNotification(status: string, progress: number, total: number, index: number) {
    // 从 electron-store 获取用户偏好
    const config = store.get('notification') || {
      masterSwitch: true,
      taskCompleted: true,
      taskFailed: true
    }

    // 如果总开关关闭，直接拦截
    if (!config.masterSwitch) return

    // 场景 A: 任务全部完成 (100%)
    if (progress === 100 && config.taskCompleted) {
      // 只有当所有子任务都完成，或者当前是单任务时才弹出
      // 如果是批量任务，你可以选择在最后一个子任务完成时通知
      if (index + 1 === total) {
        new Notification({
          title: '🎉 读书心得已生成',
          body: total > 1 ? `共 ${total} 篇心得已全部处理完成。` : '您的书籍心得已准备就绪。',
          silent: config.silentMode
        }).show()
      }
    }

    // 场景 B: 任务失败 (假设你传入的 status 是 'FAILED')
    if (status === 'FAILED' && config.taskFailed) {
      new Notification({
        title: '❌ 任务生成失败',
        body: `第 ${index + 1} 项任务执行异常，请检查网络或 API 余额。`,
        silent: config.silentMode
      }).show()
    }
  }
}

export const readingReflectionsTaskManager = new TaskManager()