import { App } from '../../../types'
import { Context } from 'koa'
import * as request from 'request-promise'
import template from '../../template'
import * as Excel from 'exceljs'
import DbClient from '../../client/db'
import i18n from '../../../service/i18n'
import * as XLSX from 'xlsx'
import * as jschardet from 'jschardet'
import * as iconv from 'iconv-lite'

interface Header {
  type: string,
  value: string
}

export default abstract class Base {
  protected app: App
  protected ctx: Context
  protected headers: string[]
  protected example: string[]
  protected dbClient: DbClient
  protected NATIVE: string = 'native'

  protected abstract headerArray: Header[]

  constructor (app: App, ctx: Context) {
    this.app = app
    this.ctx = ctx

    this.dbClient = new DbClient(this.app, this.ctx)
    if (this.ctx.state.lang) {
      i18n.setLocale(this.ctx.state.lang)
    }
  }

  abstract buildHeaders (data?, type?): Promise<this> | this
  abstract import (objArray, options): Promise<void>

  buildExample (data?, type?): Promise<this> | this {
    return this
  }

  protected translate (objectArray: Header[]) {
    return objectArray.map((item) => i18n.__(item.value))
  }

  async downloadFile(url: string, fileType: string) {
    const maxSize: number = 5 * 1024 * 1024

    if (!url || !fileType) {
      throw new Error('params missing')
    }

    let res = await request({
      method: 'head',
      url: url,
      encoding: null,
      resolveWithFullResponse: true,
      // 文件有重定向，需开启
      followRedirect: true,
      // gzip开启不会返回content-length
      gzip: false
    })

    if (res.statusCode !== 200) {
      throw new Error(`wrong statusCode ${res.statusCode}`)
    }

    const contentLength: number = Number(res.headers['content-length'])

    if (!isFinite(contentLength) || maxSize < contentLength) {
      throw new Error('invalid downloadUrl')
    }

    res = await request({
      method: 'get',
      url: url,
      encoding: null,
      resolveWithFullResponse: true,
      followRedirect: true
    })
    if (res.statusCode !== 200) {
      throw new Error(`wrong statusCode ${res.statusCode}`)
    }
    return res.body
  }

  parse(data: Buffer, fileType: string): Object[] {
    const array: Header[] = this.headerArray
    const parsedData: Object[] = []

    let workbook: XLSX.WorkBook
    if (fileType.toLowerCase() === 'csv') {
      const {encoding} = jschardet.detect(data)
      workbook = XLSX.read(iconv.decode(data, encoding), {type: 'string'})
    } else {
      workbook = XLSX.read(data)
    }

    const worksheet: any = XLSX.utils.sheet_to_json(workbook.Sheets[workbook.SheetNames[0]], { header: 1 })

    const tmpContentDeleted = worksheet[0].length > 1
    const titleIndex = tmpContentDeleted ? 0 : 1

    // 标题行为第二行
    if (worksheet[titleIndex].length !== array.length) {
      throw Error('ParamError: _scenariofieldId')
    }

    // 去除模板及标题行
    worksheet.slice(titleIndex + 1).forEach((item: string[]) => {
      const result = {}

      item.forEach((element, i) => {
        result[array[i].value] = element
      })
      parsedData.push(result)
    })

    return parsedData
  }

  async buildWorkbook(TplValue: string) {
    const workbook: Excel.Workbook = new Excel.Workbook()
    const sheetName = TplValue === 'basictestcase' ? i18n.__('basictestcaseimport') : 'template'
    const sheet: Excel.Worksheet = workbook.addWorksheet(sheetName)
    const columnsArray: Object[] = []
    let headerTpl: string = template[TplValue]

    if (this.ctx.state.lang === 'en') {
      headerTpl = template[TplValue + 'en']
    }

    /*
      文件解析中 依赖 填写规则内容 只有一项
      如果对上述依赖要修改， 请同步 parser 解析中对 填写规则内容 的判断
    */
    for (let i = 0; i < this.headers.length; i++) {
      // 第一行默认是模板
      if (i === 0) {
        columnsArray.push({
          header: headerTpl,
          width: 15,
          style: {
            alignment: {
              vertical: 'top',
              wrapText: true
            }
          }
        })
      } else {
        // 格式化每一列 style
        columnsArray.push({
          width: 15,
          style: {
            alignment: {
              vertical: 'top',
              wrapText: true
            }
          }
        })
      }
    }

    sheet.columns = columnsArray
    sheet.mergeCells('A1:Q1')
    sheet.addRow(this.headers)
    if (this.example != null) sheet.addRow(this.example)
    sheet.getRow(1).height = 260
    sheet.getCell('A1').font = {
      size: 12,
      bold: true
    }

    return workbook
  }
}