import crc32 from './crc32.js'
import http from 'axios'
import express from 'express'

const app = express()
const port = 7860

app.use(express.json())
app.use(express.urlencoded({ extended: true }))

const splitBuffer = (buffer, n) => {
  const partSize = Math.ceil(buffer.length / n)
  const parts = []
  for (let i = 0; i < n; i++) {
    const start = i * partSize
    const end = start + partSize
    parts.push(buffer.slice(start, end))
  }
  return parts
}

app.get('*', async (req, res) => {
  try {
    const file_url = req.path.replace(/^\//, '')
    const file = await http({
      method: 'GET',
      url: file_url,
      responseType: 'arraybuffer'
    })
    const files_list = splitBuffer(file.data, 5)
    const upload_info = await http({
      method: 'GET',
      url: 'https://data.emmmm.eu.org/upload/cn'
    })
    const upload_part_info = await http({
      method: 'POST',
      url: upload_info.data.url,
      params: {
        uploadmode: 'part',
        phase: 'init'
      },
      headers: {
        'authorization': upload_info.data.authorization
      }
    })
    const uploadid = upload_part_info.data.data.uploadid
    console.log(uploadid)
    const upload_list = {}
    await Promise.all(files_list.map(async (item, index) => {
      const crc32_text = crc32(item)
      let count = 1
      while (count && count <= 5) {
        const upload_result = await http({
          method: 'POST',
          url: upload_info.data.url,
          params: {
            uploadid: uploadid,
            part_number: index + 1,
            phase: 'transfer'
          },
          headers: {
            'content-crc32': crc32_text,
            'authorization': upload_info.data.authorization
          },
          data: item
        })
        if (upload_result.data.data.crc32 == crc32_text) {
          count = 0
          upload_list[index + 1] = crc32_text
        } else {
          count += 1
          if (count > 5) {
            throw Error
          }
        }
      }
    }))
    const finish = Object.entries(upload_list).map(i => i.join(':')).join(',')
    const upload_result = await http({
      method: 'POST',
      url: upload_info.data.url,
      params: {
        uploadid: uploadid,
        uploadmode: 'part',
        phase: 'finish'
      },
      headers: {
        'authorization': upload_info.data.authorization
      },
      data: finish
    })
    if (upload_result.data.code == 2000) {
      res.send(JSON.stringify({
        vid: upload_info.data.vid,
        url: `https://data.emmmm.eu.org/parse/zj/${upload_info.data.uri}`
      }))
    } else {
      throw Error
    }
  } catch (e) {
    res.send(e.toString())
  }
})

app.listen(port, async () => {
  console.log(`http://localhost:${port}`)
})