/**
 * 聊天状态管理模块
 */

import { defineStore } from 'pinia'

/**
 * 消息类型枚举
 */
export const MessageType = {
  TEXT: 1,    // 文本消息
  VOICE: 2,   // 语音消息
  IMAGE: 3    // 图片消息
}

/**
 * 消息状态枚举
 */
export const MessageStatus = {
  SENDING: 0,   // 发送中
  SENT: 1,      // 已发送
  DELIVERED: 2, // 已送达
  READ: 3,      // 已读
  FAILED: 4     // 发送失败
}

export const useChatStore = defineStore('chat', {
  state: () => ({
    // 会话列表
    sessions: [],
    // 当前会话的消息列表 (按sessionId分组)
    messagesBySession: {},
    // 当前活跃的会话ID
    currentSessionId: null,
    // 总未读消息数
    totalUnreadCount: 0
  }),

  getters: {
    /**
     * 获取当前会话的消息列表
     */
    currentMessages: (state) => {
      if (!state.currentSessionId) return []
      return state.messagesBySession[state.currentSessionId] || []
    },

    /**
     * 是否有未读消息
     */
    hasUnreadMessages: (state) => state.totalUnreadCount > 0,

    /**
     * 获取指定会话的未读数
     */
    getSessionUnreadCount: (state) => (sessionId) => {
      const session = state.sessions.find(s => s.sessionId === sessionId)
      return session ? session.unreadCount : 0
    }
  },

  actions: {
    /**
     * 设置会话列表
     */
    setSessions(sessions) {
      this.sessions = sessions
      this.updateTotalUnreadCount()
    },

    /**
     * 更新总未读消息数
     */
    updateTotalUnreadCount() {
      this.totalUnreadCount = this.sessions.reduce(
        (total, session) => total + (session.unreadCount || 0),
        0
      )
    },

    /**
     * 设置当前会话
     */
    setCurrentSession(sessionId) {
      this.currentSessionId = sessionId
    },

    /**
     * 设置会话的消息列表
     */
    setMessages(sessionId, messages) {
      this.messagesBySession[sessionId] = messages
    },

    /**
     * 添加新消息到会话
     */
    addMessage(sessionId, message) {
      if (!this.messagesBySession[sessionId]) {
        this.messagesBySession[sessionId] = []
      }
      this.messagesBySession[sessionId].push(message)
      this.updateSessionLastMessage(sessionId, message)
    },

    /**
     * 更新会话的最后消息
     */
    updateSessionLastMessage(sessionId, message) {
      const session = this.sessions.find(s => s.sessionId === sessionId)
      if (session) {
        session.lastMessage = this.getMessagePreview(message)
        session.lastMessageTime = message.createTime
      }
    },

    /**
     * 获取消息预览文本
     */
    getMessagePreview(message) {
      switch (message.messageType) {
        case MessageType.TEXT:
          return message.content
        case MessageType.VOICE:
          return '[语音]'
        case MessageType.IMAGE:
          return '[图片]'
        default:
          return message.content || ''
      }
    },

    /**
     * 接收新消息
     */
    receiveMessage(message) {
      const { sessionId } = message
      this.addMessage(sessionId, message)
      
      if (sessionId !== this.currentSessionId) {
        this.incrementUnreadCount(sessionId)
      }
    },

    /**
     * 增加会话未读数
     */
    incrementUnreadCount(sessionId) {
      const session = this.sessions.find(s => s.sessionId === sessionId)
      if (session) {
        session.unreadCount = (session.unreadCount || 0) + 1
        this.updateTotalUnreadCount()
      }
    },

    /**
     * 标记会话已读
     */
    markSessionAsRead(sessionId) {
      const session = this.sessions.find(s => s.sessionId === sessionId)
      if (session && session.unreadCount > 0) {
        session.unreadCount = 0
        this.updateTotalUnreadCount()
      }
    },

    /**
     * 发送消息（本地状态更新）
     */
    sendMessage(sessionId, messageData) {
      const message = {
        id: Date.now(),
        sessionId,
        senderId: messageData.senderId,
        receiverId: messageData.receiverId,
        messageType: messageData.messageType || MessageType.TEXT,
        content: messageData.content,
        status: MessageStatus.SENDING,
        createTime: new Date().toISOString(),
        isMine: true
      }
      
      this.addMessage(sessionId, message)
      return message
    },

    /**
     * 更新消息状态
     */
    updateMessageStatus(sessionId, messageId, status) {
      const messages = this.messagesBySession[sessionId]
      if (messages) {
        const message = messages.find(m => m.id === messageId)
        if (message) {
          message.status = status
        }
      }
    },

    /**
     * 清空当前会话
     */
    clearCurrentSession() {
      this.currentSessionId = null
    },

    /**
     * 重置聊天状态
     */
    reset() {
      this.sessions = []
      this.messagesBySession = {}
      this.currentSessionId = null
      this.totalUnreadCount = 0
    }
  }
})