const axios = require('axios')
const FormData = require('form-data')
const crypto = require('crypto')
const accountManager = require('./manager')
const imageProcessor = require('./imageProcessor')
const logger = require('./logger')

class ImageUploader {
  constructor() {
    this.uploadUrl = 'https://mammouth.ai/api/attachments/saveFile'
    this.imageCache = new Map()
  }


  generateHash(buffer) {
    return crypto.createHash('sha256').update(buffer).digest('hex')
  }

  async uploadImage(imageBuffer, imageName) {
    // 确保参数有效
    if (!imageBuffer || !Buffer.isBuffer(imageBuffer)) {
      throw new Error('无效的图片数据')
    }

    if (!imageName) {
      imageName = `image_${Date.now()}.png`
    }

    // 生成图片数据的哈希值作为缓存key
    const imageHash = this.generateHash(imageBuffer)

    // 检查缓存中是否已存在该图片的上传结果
    if (this.imageCache.has(imageHash)) {
      console.log(`图片缓存命中: ${imageHash.substring(0, 8)}...`)
      return this.imageCache.get(imageHash)
    }

    console.log(`图片缓存未命中，开始上传: ${imageHash.substring(0, 8)}...`)

    // 获取一个可用的cookie
    const cookieValue = accountManager.getNextAvailableCookie()
    if (!cookieValue) {
      throw new Error('没有可用的账号')
    }

    // 创建FormData对象
    const form = new FormData()
    form.append('type', 'image')
    form.append('name', imageName)
    form.append('file', imageBuffer, {
      filename: 'blob',
      contentType: 'image/png' // 默认为PNG，可根据实际情况调整
    })

    try {
      // 发送请求
      const response = await axios.post(this.uploadUrl, form, {
        headers: {
          ...form.getHeaders(),
          'Cookie': `auth_session=${cookieValue}`,
          'Origin': 'https://mammouth.ai',
          'Referer': 'https://mammouth.ai/app/a/default'
        }
      })

      // 检查响应
      if (response.data && response.data.location) {
        const imageUrl = response.data.location

        // 将结果保存到缓存
        this.imageCache.set(imageHash, imageUrl)
        console.log(`图片上传成功并缓存: ${imageHash.substring(0, 8)}... -> ${imageUrl}`)

        return imageUrl
      } else {
        throw new Error('上传成功但返回格式不正确')
      }
    } catch (error) {
      // 如果是账号限制问题，尝试其他账号
      if (error.response && error.response.status === 403) {
        accountManager.markAsUnavailable(cookieValue)
        // 递归尝试使用新账号
        return this.uploadImage(imageBuffer, imageName)
      }

      throw new Error(`图片上传失败: ${error.message}`)
    }
  }

  async uploadFromBase64(base64String, imageName) {
    // 处理base64字符串，移除可能的前缀
    const base64Data = base64String.replace(/^data:image\/\w+;base64,/, '')
    const buffer = Buffer.from(base64Data, 'base64')
    
    // 如果提供了前缀，则从中提取图片类型
    let fileExt = 'png'
    const mimeMatch = base64String.match(/^data:image\/(\w+);base64,/)
    if (mimeMatch && mimeMatch[1]) {
      fileExt = mimeMatch[1]
    }
    
    // 如果没有提供文件名，则使用哈希值的前8位和时间戳生成
    if (!imageName) {
      const hash = this.generateHash(buffer).substring(0, 8)
      imageName = `image_${hash}_${Date.now()}.${fileExt}`
    }
    
    return this.uploadImage(buffer, imageName)
  }

  async uploadFromUrl(imageUrl, imageName) {
    try {
      // 下载图片
      const response = await axios.get(imageUrl, {
        responseType: 'arraybuffer'
      })
      
      // 从URL中提取文件扩展名
      let fileExt = 'png'
      const urlMatch = imageUrl.match(/\.([a-zA-Z0-9]+)(?:\?.*)?$/)
      if (urlMatch && urlMatch[1]) {
        fileExt = urlMatch[1].toLowerCase()
      }
      
      // 生成buffer并计算哈希
      const buffer = Buffer.from(response.data)
      
      // 如果没有提供文件名，则使用哈希值的前8位和时间戳生成
      if (!imageName) {
        const hash = this.generateHash(buffer).substring(0, 8)
        imageName = `image_${hash}_${Date.now()}.${fileExt}`
      }
      
      return this.uploadImage(buffer, imageName)
    } catch (error) {
      throw new Error(`从URL获取图片失败: ${error.message}`)
    }
  }
  
  getCacheStats() {
    return {
      size: this.imageCache.size,
      keys: Array.from(this.imageCache.keys()).map(k => k.substring(0, 8) + '...')
    }
  }
  
  clearCache() {
    const oldSize = this.imageCache.size
    this.imageCache.clear()
    return { cleared: oldSize }
  }

  /**
   * 智能上传图片（支持长图处理）
   * @param {Buffer} imageBuffer - 图片缓冲区
   * @param {string} imageName - 图片名称
   * @param {string} requestId - 请求ID（用于日志）
   * @param {number} imageIndex - 图片索引（用于日志）
   * @returns {Promise<Array<string>>} 上传后的URL数组
   */
  async uploadImageSmart(imageBuffer, imageName, requestId = null, imageIndex = 0) {
    try {
      // 检测是否为长图
      const detection = await imageProcessor.detectLongImage(imageBuffer)

      if (requestId) {
        logger.logLongImageDetection(requestId, imageIndex, detection)
      }

      if (!detection.isLongImage) {
        // 不是长图，使用原有方式上传
        const url = await this.uploadImage(imageBuffer, imageName)

        if (requestId) {
          logger.logImageUpload(requestId, imageIndex, 0, true, url)
        }

        return [url]
      }

      // 是长图，进行切割处理
      console.log(`检测到长图 ${detection.width}x${detection.height}，开始切割处理`)

      try {
        const segments = await imageProcessor.cropLongImage(imageBuffer)

        if (!segments || segments.length === 0) {
          throw new Error('长图切割失败：未生成任何片段')
        }

        if (requestId) {
          logger.logImageCropping(requestId, imageIndex, {
            segments,
            stats: imageProcessor.getProcessingStats(segments)
          })
        }

        // 并行上传切割后的片段
        const uploadPromises = segments.map(async (segment) => {
          const segmentName = imageProcessor.generateSegmentName(
            imageName,
            segment.metadata.segmentIndex,
            segment.metadata.totalSegments
          )

          try {
            const url = await this.uploadImage(segment.buffer, segmentName)

            if (requestId) {
              logger.logImageUpload(requestId, imageIndex, segment.metadata.segmentIndex, true, url)
            }

            console.log(`片段 ${segment.metadata.segmentIndex + 1}/${segment.metadata.totalSegments} 上传成功: ${url}`)
            return {
              url,
              segmentIndex: segment.metadata.segmentIndex,
              success: true
            }
          } catch (error) {
            if (requestId) {
              logger.logImageUpload(requestId, imageIndex, segment.metadata.segmentIndex, false, null, error.message)
            }

            console.error(`片段 ${segment.metadata.segmentIndex + 1} 上传失败: ${error.message}`)
            return {
              error: error.message,
              segmentIndex: segment.metadata.segmentIndex,
              success: false
            }
          }
        })

        // 等待所有上传完成
        const uploadResults = await Promise.all(uploadPromises)

        // 检查是否有失败的上传
        const failedUploads = uploadResults.filter(result => !result.success)
        if (failedUploads.length > 0) {
          const failedIndexes = failedUploads.map(result => result.segmentIndex + 1).join(', ')
          throw new Error(`片段 ${failedIndexes} 上传失败`)
        }

        // 按照片段顺序排序并提取URL
        const sortedResults = uploadResults
          .filter(result => result.success)
          .sort((a, b) => a.segmentIndex - b.segmentIndex)
          .map(result => result.url)

        console.log(`长图切割并行上传完成，共 ${sortedResults.length} 个片段`)
        return sortedResults

      } catch (longImageError) {
        // 长图处理失败，回退到原图上传
        console.warn(`长图处理失败: ${longImageError.message}，回退到原图上传`)

        if (requestId) {
          logger.logError(requestId, 'LONG_IMAGE_FALLBACK', `长图处理失败，回退到原图: ${longImageError.message}`, {
            imageIndex,
            originalSize: `${detection.width}x${detection.height}`
          })
        }

        try {
          const fallbackUrl = await this.uploadImage(imageBuffer, imageName)

          if (requestId) {
            logger.logImageUpload(requestId, imageIndex, 0, true, fallbackUrl, '长图回退上传')
          }

          console.log(`长图回退上传成功: ${fallbackUrl}`)
          return [fallbackUrl]
        } catch (fallbackError) {
          throw new Error(`长图处理和回退上传均失败: ${longImageError.message} | ${fallbackError.message}`)
        }
      }

    } catch (error) {
      if (requestId) {
        logger.logError(requestId, 'IMAGE_UPLOAD_ERROR', error.message, {
          imageIndex,
          imageName
        })
      }
      throw error
    }
  }

  /**
   * 智能上传Base64图片（支持长图处理）
   * @param {string} base64String - Base64字符串
   * @param {string} imageName - 图片名称
   * @param {string} requestId - 请求ID（用于日志）
   * @param {number} imageIndex - 图片索引（用于日志）
   * @param {boolean} preserveOrder - 是否保持顺序（禁用缓存优化）
   * @returns {Promise<Array<string>>} 上传后的URL数组
   */
  async uploadFromBase64Smart(base64String, imageName, requestId = null, imageIndex = 0, preserveOrder = false) {
    // 处理base64字符串，移除可能的前缀
    const base64Data = base64String.replace(/^data:image\/\w+;base64,/, '')
    const buffer = Buffer.from(base64Data, 'base64')

    // 如果提供了前缀，则从中提取图片类型
    let fileExt = 'png'
    const mimeMatch = base64String.match(/^data:image\/(\w+);base64,/)
    if (mimeMatch && mimeMatch[1]) {
      fileExt = mimeMatch[1]
    }

    // 如果没有提供文件名，则使用哈希值的前8位和时间戳生成
    if (!imageName) {
      const hash = this.generateHash(buffer).substring(0, 8)
      imageName = `image_${hash}_${Date.now()}.${fileExt}`
    }

    return this.uploadImageSmart(buffer, imageName, requestId, imageIndex, preserveOrder)
  }

  /**
   * 智能上传URL图片（支持长图处理）
   * @param {string} imageUrl - 图片URL
   * @param {string} imageName - 图片名称
   * @param {string} requestId - 请求ID（用于日志）
   * @param {number} imageIndex - 图片索引（用于日志）
   * @param {boolean} preserveOrder - 是否保持顺序（禁用缓存优化）
   * @returns {Promise<Array<string>>} 上传后的URL数组
   */
  async uploadFromUrlSmart(imageUrl, imageName, requestId = null, imageIndex = 0, preserveOrder = false) {
    try {
      // 下载图片
      const response = await axios.get(imageUrl, {
        responseType: 'arraybuffer'
      })

      // 从URL中提取文件扩展名
      let fileExt = 'png'
      const urlMatch = imageUrl.match(/\.([a-zA-Z0-9]+)(?:\?.*)?$/)
      if (urlMatch && urlMatch[1]) {
        fileExt = urlMatch[1].toLowerCase()
      }

      // 生成buffer并计算哈希
      const buffer = Buffer.from(response.data)

      // 如果没有提供文件名，则使用哈希值的前8位和时间戳生成
      if (!imageName) {
        const hash = this.generateHash(buffer).substring(0, 8)
        imageName = `image_${hash}_${Date.now()}.${fileExt}`
      }

      return this.uploadImageSmart(buffer, imageName, requestId, imageIndex, preserveOrder)
    } catch (error) {
      throw new Error(`从URL获取图片失败: ${error.message}`)
    }
  }
}


module.exports = new ImageUploader()