import paginate from 'do-paginate'

  const index: number = 5
  const items_per_page: number = 25
  const items_total: number = 5000
  const offset: number = 5

  const sequence: Array<number> =
    paginate(index, items_per_page, items_total, offset) // [ 1,2,3,4,5,6,7,8,9,10,11 ]

  // typescript example with express route
  import express from 'express'
  import paginate from 'do-paginate'
  import cors from 'cors'

  const app = express()

  app.use(cors({ origin: '*' }))

  // request url: /
  app.get('/', async (_, res) =>
    res.send("<a href='/index=1&limit=25'>test pagination</a>")
  )

  // request url: /index=1&limit=25
  app.get('/index=:index?&limit=:limit?', async (req, res) => {
    const d_index: number = 1 // default index - used if, for example, none is passed in
    const d_limit: number = 25 // default limit - used if, for example, none is passed in
    const offset: number = 5 // pages to generate

    // get index from url, else fallback to d_index
    const index: number =
      +(req.params?.['index'] as string)?.replace(/[^\d-]/gm, '') || d_index
    // get limit from url, else fallback to d_limit
    const limit: number =
      +(req.params?.['limit'] as string)?.replace(/[^\d-]/gm, '') || d_limit

    const items_total: number = 5000 // TODO: get total items

    const pages: Array<number> = paginate(index, limit, items_total, offset)

    // TODO: query database based on: index, limit, and add items to response

    res.send(
      [
        `<a href=/index=${index - 1}&limit=${limit}> < </a>`,
        pages
          .map(
            (x: number, _: number) =>
            `<a href='/index=${x}&limit=${limit}' style="min-width: 18px; text-align: center; display: inline-block;">${x}</a>`
          )
          .join('\n'),
        `<a href=/index=${index + 1}&limit=${limit}> > </a>`,
      ].join('')
    )
  })

  app.listen(process.env.PORT || 8000, () => {
    console.info(`Server started on port ${process.env.PORT || 8000}`)
  })