import http from './http.js'
import store from '@/store/index.js'

export default {
  /**
   * 发送消息到Dify API
   * @param {string} message 用户消息内容
   * @param {Object} options 配置选项
   * @returns {Promise} 
   */
  async sendMessage(message, options = {}) {
    try {
      // 获取AI配置
      const aiConfig = store.getters.globalAIAgentConfig
      
      // 构建Dify API请求参数
      const params = {
        url: '/api/ai/chat', // 后端代理接口
        data: {
          message: message,
          conversation_id: options.conversationId || this.generateConversationId(),
          user_id: store.state.memberInfo?.id || 'anonymous',
          stream: options.stream || false, // 是否流式响应
          // Dify API参数
          inputs: {},
          query: message,
          response_mode: options.stream ? 'streaming' : 'blocking',
          user: store.state.memberInfo?.id || 'anonymous'
        },
        header: {
          'Content-Type': 'application/json'
        }
      }
      
      // 如果有Dify配置，添加API密钥
      if (aiConfig?.difyApiKey) {
        params.header['Authorization'] = `Bearer ${aiConfig.difyApiKey}`
      }
      
      if (aiConfig?.difyBaseUrl) {
        params.header['X-Dify-Url'] = aiConfig.difyBaseUrl
      }
      
      // 发送请求
      const response = await http.sendRequest({
        ...params,
        async: false // 使用Promise方式
      })
      
      return this.handleResponse(response, options)
      
    } catch (error) {
      console.error('Dify API请求失败:', error)
      throw new Error('AI服务暂时不可用，请稍后重试')
    }
  },
  
  /**
   * 流式消息处理
   * @param {string} message 用户消息
   * @param {Function} onChunk 流式数据回调
   * @param {Function} onComplete 完成回调
   */
  async sendStreamMessage(message, onChunk, onComplete) {
    try {
      const aiConfig = store.getters.globalAIAgentConfig
      
      // 检查配置
      if (!aiConfig?.difyBaseUrl || !aiConfig?.difyApiKey) {
        throw new Error('未配置Dify服务')
      }
      
      // 创建WebSocket连接或使用Server-Sent Events
      if (aiConfig?.difyWsUrl) {
        return this.connectWebSocket(message, onChunk, onComplete)
      } else {
        // 使用HTTP流式请求
        return this.sendHttpStream(message, onChunk, onComplete)
      }
      
    } catch (error) {
      console.error('流式消息发送失败:', error)
      throw error
    }
  },
  
  /**
   * WebSocket连接
   */
  connectWebSocket(message, onChunk, onComplete) {
    return new Promise((resolve, reject) => {
      const aiConfig = store.getters.globalAIAgentConfig
      const wsUrl = aiConfig.difyWsUrl
      
      if (!wsUrl) {
        reject(new Error('未配置WebSocket地址'))
        return
      }
      
      // #ifdef H5
      const ws = new WebSocket(wsUrl)
      
      ws.onopen = () => {
        // 发送消息
        ws.send(JSON.stringify({
          message: message,
          user_id: store.state.memberInfo?.id || 'anonymous',
          conversation_id: this.generateConversationId()
        }))
      }
      
      ws.onmessage = (event) => {
        try {
          const data = JSON.parse(event.data)
          if (data.type === 'chunk' && onChunk) {
            onChunk(data.content)
          } else if (data.type === 'complete' && onComplete) {
            onComplete(data.content)
            ws.close()
            resolve(data.content)
          }
        } catch (e) {
          console.error('WebSocket消息解析失败:', e)
        }
      }
      
      ws.onerror = (error) => {
        console.error('WebSocket连接错误:', error)
        reject(error)
      }
      
      ws.onclose = () => {
        console.log('WebSocket连接关闭')
      }
      // #endif
      
      // #ifdef MP-WEIXIN || APP-PLUS
      // 小程序和APP使用uni.connectSocket
      uni.connectSocket({
        url: wsUrl,
        success: () => {
          uni.onSocketOpen(() => {
            uni.sendSocketMessage({
              data: JSON.stringify({
                message: message,
                user_id: store.state.memberInfo?.id || 'anonymous',
                conversation_id: this.generateConversationId()
              })
            })
          })
          
          uni.onSocketMessage((res) => {
            try {
              const data = JSON.parse(res.data)
              if (data.type === 'chunk' && onChunk) {
                onChunk(data.content)
              } else if (data.type === 'complete' && onComplete) {
                onComplete(data.content)
                uni.closeSocket()
                resolve(data.content)
              }
            } catch (e) {
              console.error('WebSocket消息解析失败:', e)
            }
          })
          
          uni.onSocketError((error) => {
            console.error('WebSocket连接错误:', error)
            reject(error)
          })
        },
        fail: (error) => {
          reject(error)
        }
      })
      // #endif
    })
  },
  
  /**
   * HTTP流式请求
   */
  async sendHttpStream(message, onChunk, onComplete) {
    const aiConfig = store.getters.globalAIAgentConfig
    
    const params = {
      url: '/api/ai/chat-stream',
      data: {
        message: message,
        conversation_id: this.generateConversationId(),
        user_id: store.state.memberInfo?.id || 'anonymous',
        stream: true
      },
      header: {
        'Content-Type': 'application/json'
      }
    }
    
    if (aiConfig?.difyApiKey) {
      params.header['Authorization'] = `Bearer ${aiConfig.difyApiKey}`
    }
    
    // 使用fetch API进行流式请求（H5环境）
    // #ifdef H5
    try {
      const response = await fetch(`${aiConfig.difyBaseUrl}/chat-messages`, {
        method: 'POST',
        headers: {
          'Content-Type': 'application/json',
          'Authorization': `Bearer ${aiConfig.difyApiKey}`
        },
        body: JSON.stringify({
          inputs: {},
          query: message,
          response_mode: 'streaming',
          user: store.state.memberInfo?.id || 'anonymous'
        })
      })
      
      const reader = response.body.getReader()
      const decoder = new TextDecoder()
      let content = ''
      
      while (true) {
        const { done, value } = await reader.read()
        if (done) break
        
        const chunk = decoder.decode(value)
        const lines = chunk.split('\n')
        
        for (const line of lines) {
          if (line.startsWith('data: ')) {
            try {
              const data = JSON.parse(line.slice(6))
              if (data.event === 'text_message' && data.text) {
                content += data.text
                if (onChunk) onChunk(data.text)
              }
            } catch (e) {
              // 忽略解析错误
            }
          }
        }
      }
      
      if (onComplete) onComplete(content)
      return content
      
    } catch (error) {
      console.error('HTTP流式请求失败:', error)
      throw error
    }
    // #endif
    
    // 非H5环境使用普通请求模拟流式效果
    // #ifndef H5
    const response = await http.sendRequest({
      ...params,
      async: false
    })
    
    // 模拟流式效果
    if (response.success && response.data) {
      const content = response.data
      const chunkSize = 3
      let index = 0
      
      const streamInterval = setInterval(() => {
        if (index < content.length) {
          const chunk = content.substring(index, index + chunkSize)
          index += chunkSize
          if (onChunk) onChunk(chunk)
        } else {
          clearInterval(streamInterval)
          if (onComplete) onComplete(content)
        }
      }, 100)
    }
    // #endif
  },
  
  /**
   * 处理API响应
   */
  handleResponse(response, options) {
    if (response.code === 0 || response.success) {
      return {
        success: true,
        content: response.data?.answer || response.data?.content || response.data,
        conversationId: response.data?.conversation_id,
        messageId: response.data?.message_id
      }
    } else {
      throw new Error(response.message || 'AI服务返回错误')
    }
  },
  
  /**
   * 生成会话ID
   */
  generateConversationId() {
    return 'conv_' + Date.now() + '_' + Math.random().toString(36).substr(2, 9)
  },
  
  /**
   * 获取AI服务状态
   */
  async getServiceStatus() {
    try {
      const aiConfig = store.getters.globalAIAgentConfig
      
      if (!aiConfig?.difyBaseUrl || !aiConfig?.difyApiKey) {
        return {
          available: false,
          reason: '未配置Dify服务'
        }
      }
      
      // 简单的健康检查
      const response = await http.sendRequest({
        url: '/api/ai/health',
        async: false
      })
      
      return {
        available: response.success,
        reason: response.success ? '服务正常' : '服务异常'
      }
      
    } catch (error) {
      return {
        available: false,
        reason: '服务检查失败'
      }
    }
  },
  
  /**
   * 清除会话历史
   */
  async clearConversation(conversationId) {
    try {
      const response = await http.sendRequest({
        url: '/api/ai/clear-conversation',
        data: { conversation_id: conversationId },
        async: false
      })
      
      return response.success
      
    } catch (error) {
      console.error('清除会话失败:', error)
      return false
    }
  }
}